DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited.

NONRESIDENTTRAININGCOURSE

March 1990

Aircrew SurvivalEquipmentman 2NAVEDTRA 14218

DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited.

Although the words “he,” “him,” and“his” are used sparingly in this course toenhance communication, they are notintended to be gender driven or to affront ordiscriminate against anyone.

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PREFACE

By enrolling in this self-study course, you have demonstrated a desire to improve yourself and the Navy.Remember, however, this self-study course is only one part of the total Navy training program. Practicalexperience, schools, selected reading, and your desire to succeed are also necessary to successfully roundout a fully meaningful training program.

THE COURSE: This self-study course is organized into subject matter areas, each containing learningobjectives to help you determine what you should learn along with text and illustrations to help youunderstand the information. The subject matter reflects day-to-day requirements and experiences ofpersonnel in the rating or skill area. It also reflects guidance provided by Enlisted Community Managers(ECMs) and other senior personnel, technical references, instructions, etc., and either the occupational ornaval standards, which are listed in the Manual of Navy Enlisted Manpower Personnel Classificationsand Occupational Standards, NAVPERS 18068.

THE QUESTIONS: The questions that appear in this course are designed to help you understand thematerial in the text.

VALUE: In completing this course, you will improve your military and professional knowledge.Importantly, it can also help you study for the Navy-wide advancement in rate examination. If you arestudying and discover a reference in the text to another publication for further information, look it up.

1990 Edition Prepared byPRCM Harold G. Lyter

Published byNAVAL EDUCATION AND TRAINING

PROFESSIONAL DEVELOPMENTAND TECHNOLOGY CENTER

NAVSUP Logistics Tracking Number0504-LP-022-3680

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Sailor’s Creed

“ I am a United States Sailor.

I will support and defend theConstitution of the United States ofAmerica and I will obey the ordersof those appointed over me.

I represent the fighting spirit of theNavy and those who have gonebefore me to defend freedom anddemocracy around the world.

I proudly serve my country’s Navycombat team with honor, courageand commitment.

I am committed to excellence andthe fair treatment of all.”

CONTENTS

CHAPTER

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

Personnel Parachute Familiarization . . . . . . . . . . . . . . . . .

Automatic Opening Devices . . . . . . . . . . . . . . . . . . . . . . . . .

NES-12 Personnel Parachute System . . . . . . . . . . . . . . . . .

Aircrew Personal Protective Equipment . . . . . . . . . . . . . .

Rescue and Survival Equipment . . . . . . . . . . . . . . . . . . . . .

Inflatable Survival Equipment.. . . . . . . . . . . . . . . . . . . . . .

Seat Survival Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Carbon Dioxide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sewing Machines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fabrication and Manufacture.. . . . . . . . . . . . . . . . . . . . . .

Oxygen Components Test Stands . . . . . . . . . . . . . . . . . . . .

Oxygen Related Components. . . . . . . . . . . . . . . . . . . . . . . .

APPENDIX

I. Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

II. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Page

1-1

2-1

3-1

4-1

5-1

6-1

7-1

8-1

9-1

10-1

11-1

12-1

AI-1

AII-1

INDEX-1

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INSTRUCTIONS FOR TAKING THE COURSE

ASSIGNMENTS

The text pages that you are to study are listed atthe beginning of each assignment. Study thesepages carefully before attempting to answer thequestions. Pay close attention to tables andillustrations and read the learning objectives.The learning objectives state what you should beable to do after studying the material. Answeringthe questions correctly helps you accomplish theobjectives.

SELECTING YOUR ANSWERS

Read each question carefully, then select theBEST answer. You may refer freely to the text.The answers must be the result of your ownwork and decisions. You are prohibited fromreferring to or copying the answers of others andfrom giving answers to anyone else taking thecourse.

SUBMITTING YOUR ASSIGNMENTS

To have your assignments graded, you must beenrolled in the course with the NonresidentTraining Course Administration Branch at theNaval Education and Training ProfessionalDevelopment and Technology Center(NETPDTC). Following enrollment, there aretwo ways of having your assignments graded:(1) use the Internet to submit your assignmentsas you complete them, or (2) send all theassignments at one time by mail to NETPDTC.

Grading on the Internet: Advantages toInternet grading are:

• you may submit your answers as soon asyou complete an assignment, and

• you get your results faster; usually by thenext working day (approximately 24 hours).

In addition to receiving grade results for eachassignment, you will receive course completionconfirmation once you have completed all the

assignments. To submit your assignmentanswers via the Internet, go to:

http://courses.cnet.navy.mil

Grading by Mail: When you submit answersheets by mail, send all of your assignments atone time. Do NOT submit individual answersheets for grading. Mail all of your assignmentsin an envelope, which you either provideyourself or obtain from your nearest EducationalServices Officer (ESO). Submit answer sheetsto:

COMMANDING OFFICERNETPDTC N3316490 SAUFLEY FIELD ROADPENSACOLA FL 32559-5000

Answer Sheets: All courses include one“scannable” answer sheet for each assignment.These answer sheets are preprinted with yourSSN, name, assignment number, and coursenumber. Explanations for completing the answersheets are on the answer sheet.

Do not use answer sheet reproductions: Useonly the original answer sheets that weprovide—reproductions will not work with ourscanning equipment and cannot be processed.

Follow the instructions for marking youranswers on the answer sheet. Be sure that blocks1, 2, and 3 are filled in correctly. Thisinformation is necessary for your course to beproperly processed and for you to receive creditfor your work.

COMPLETION TIME

Courses must be completed within 12 monthsfrom the date of enrollment. This includes timerequired to resubmit failed assignments.

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PASS/FAIL ASSIGNMENT PROCEDURES

If your overall course score is 3.2 or higher, youwill pass the course and will not be required toresubmit assignments. Once your assignmentshave been graded you will receive coursecompletion confirmation.

If you receive less than a 3.2 on any assignmentand your overall course score is below 3.2, youwill be given the opportunity to resubmit failedassignments. You may resubmit failedassignments only once. Internet students willreceive notification when they have failed anassignment--they may then resubmit failedassignments on the web site. Internet studentsmay view and print results for failedassignments from the web site. Students whosubmit by mail will receive a failing result letterand a new answer sheet for resubmission of eachfailed assignment.

COMPLETION CONFIRMATION

After successfully completing this course, youwill receive a letter of completion.

ERRATA

Errata are used to correct minor errors or deleteobsolete information in a course. Errata mayalso be used to provide instructions to thestudent. If a course has an errata, it will beincluded as the first page(s) after the front cover.Errata for all courses can be accessed andviewed/downloaded at:

http:/ /www.advancement.cnet .navy.mil

STUDENT FEEDBACK QUESTIONS

We value your suggestions, questions, andcriticisms on our courses. If you would like tocommunicate with us regarding this course, weencourage you, if possible, to use e-mail. If youwrite or fax, please use a copy of the StudentComment form that follows this page.

For subject matter questions:

E-mail: n315.products@cnet.navy.milPhone: Comm: (850) 452-1777

DSN: 922-1777FAX: (850) 452-1370(Do not fax answer sheets.)

Address: COMMANDING OFFICERNETPDTC (CODE N315)6490 SAUFLEY FIELD ROADPENSACOLA FL 32509-5237

For enrollment, shipping, grading, orcompletion letter questions

E-mail: n331@cnet.navy.milPhone: Comm: (850) 452-1511/1181/1859

DSN: 922-1511/1181/1859FAX: (850) 452-1370(Do not fax answer sheets.)

Address: COMMANDING OFFICERNETPDTC (CODE N331)6490 SAUFLEY FIELD ROADPENSACOLA FL 32559-5000

NAVAL RESERVE RETIREMENT CREDIT

If you are a member of the Naval Reserve, youwill receive retirement points if you areauthorized to receive them under currentdirectives governing retirement of NavalReserve personnel. For Naval Reserveretirement, this course is evaluated at 10 points.(Refer to Administrative Procedures for NavalReservists on Inactive Duty, BUPERSINST1001.39, for more information about retirementpoints.)

COURSE OBJECTIVES

In completing this nonresident training course,you will demonstrate a knowledge of the subjectmatter by correctly answering questions on thefollowing: Personnel parachute familiarization;automatic opening devices; NES-12 personnelparachute system; protective equipment; rescueand survival equipment; inflatable survivalequipment; seat survival kit; carbon dioxide;sewing machines; fabrication and manufacture;oxygen test stands and oxygen relatedcomponents.

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Student Comments

Course Title: Aircrew Survival Equipmentman 2

NAVEDTRA: 14218 Date:

We need some information about you:

Rate/Rank and Name: SSN: Command/Unit

Street Address: City: State/FPO: Zip

Your comments, suggestions, etc.:

Privacy Act Statement: Under authority of Title 5, USC 301, information regarding your military status isrequested in processing your comments and in preparing a reply. This information will not be divulged withoutwritten authorization to anyone other than those within DOD for official use in determining performance.

NETPDTC 1550/41 (Rev 4-00)

CHAPTER 1

PERSONNEL PARACHUTE FAMILIARIZATION

Learning Objective: Upon completion of this chapter, you will be able torecognize and understand the history, components, and publications used tomaintain personnel emergency parachute assemblies.

The word parachute is, in the modern sense,derived from the Italian word parare, meaning toprotect or shield from, and the French wordchute, meaning a fall or quick descent—literally,“to protect from a fall.” As early as the year 1300,Chinese experimenters are reported to havejumped off the Great Wall with devices re-sembling umbrellas. In the year 1495, the greatgenius, artist, and inventor, Leonardo da Vinci,sketched a parachute design to be made of caulkedlinen that would permit a gentle descent to earth.About a century later, Fausto Veranzio describedand sketched a parachute design consisting of afour-poled square frame covered with fabric,which he claimed could be used to escape fromtall, burning buildings. Since man, not yetairborne, had no use for a lifesaving device of thisnature at that time, parachutes were considerednovelties or items of amusement, and interest inthem gradually lessened. It was not until theinvention of the first aerial balloon that interestin the parachute was renewed. As a result of theballoon, the parachute became less of a toy andmore a means of escape.

In the late 1700’s, the Montgolfier brothershad invented a balloon that would stay aloft. Thisballoon was kept in the air by burning bundlesof straw beneath the bag to furnish the necessarysupply of hot air. If the fabric caught fire, theflight was abruptly ended. This meant that thosewho went up on such flights had to have a meansof escape. Those early days of ballooning sawexcursions of curiosity into the use of parachutesby early balloonists such as the Montgolfiers,Blanchard, Martyn, Arnold, Appleby, Hampton,and others. Some parachute drops, using animalsas passengers, were successfully made. The firsthuman parachute descent was accomplished bythe famous French balloonist Andre-JacquesGarnerin, on 22 October 1798. This historic event

took place over Monceau Park, near Paris, whenGarnerin released himself and his semirigidparachute from the balloon at an altitude of 6,000feet.

On 14 July 1808, a famous Polish balloonist,Jodaki Kuparento, was the first man to have hislife saved from a flaming bag of hot air when,over Warsaw, remnants of his burning balloonblew into the balloon’s net structure and blos-somed into a parachute, lowering him to theground safely. However, the need for a foolproofparachute-whose main role at that time was itsuse as an added thrill to balloon ascensions-wasnot strong enough to stimulate a great deal ofinventive effort until nearly 100 years later.Hence, with the coming of the air age in 1903,when the Wright brothers made their spectacularflight at Kitty Hawk, North Carolina, there camealso an era of experimentation with parachutesdesigned for this new type of flying machine.

Albert Berry is credited with being the firstperson to successfully jump from an aircraft usinga parachute. This jump was made on March 1,1912, from a Benoist Pusher Biplane, at JeffersonBarracks, not far from Kinloch Park “Aero-drome,” St. Louis. The parachute was anunbleached muslin cotton parachute, 36 feet indiameter. Its suspension lines terminated into atrapeze bar and strap arrangement. The parachuteassembly was packed into a cone attached underthe airplane. It was retained within the metal coneby a series of break cords. The weight of Berry’sfalling body pulled the canopy and lines from thecontainer. Many others, using makeshift orexperimental parachutes, made descents beforeWorld War I, but parachutes still were notconsidered essential equipment for militaryaviators. As World War I progressed, theresultant mortality rate among pilots was veryhigh. However, the lives of over 800 balloonist

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observers and artillery fire directors were savedby parachutes, demonstrating a desperate need fora foolproof and practical lifesaving device foraviators. The next step was to improve parachutereliability and make them mandatory for militaryfliers.

Parachute lore tells us that in 1917 a Frenchpilot attacked a German Fokker and riddled itwith bullets. The plane exploded in flames andbegan to plunge to earth. As the Frenchmancircled his kill, he was surprised to see the enemypilot jump, immediately followed by a ribbon ofwhite swing out behind him as he fell through theclouds. Still amazed, he watched as a greatbillowing canopy fluttered and opened. Theplummeting body slowed with a jerk and beganswaying gently beneath the air-filled blossom. Theadversary waved at the stunned victor andproceeded to swing into no man’s land, where thereception was far from friendly. Twenty-sevenrifle and machine gun bullets were pumped intothe German’s legs. He survived and gained thehonor of being the first person to save his life byan emergency escape from an airplane.

Official documentation reveals that regularemergency bailouts were made during the latemonths of 1918 by German aviators. Capturedequipment showed the parachute to be a uniqueone designed by Heineke. Gradually, Germanfighter pilots began to equip themselves withparachutes. Soon, whole squadrons were doingthe same. At the end of the war, it was reportedthat all fliers in the entire German Air Force werein the process of wearing parachutes in flight.

All parachutes, however clever in design, werestill dependent upon a static line attached to theaircraft to deploy the parachute, and they werefar from perfect. Thus, some emergency escapeattempts continued to take lives. Towards the endof 1918, with the war coming to a close, demandsby the flying public and Congress finally resultedin the formation of a U.S. Air Service ParachuteBoard at McCook Field in Dayton, Ohio. FloydSmith, with a reputation for his ideas in parachutedesign, was put in charge of this new unit of theEngineering Division. He surrounded himself withGuy M. Ball, James M. Russel, James J. Higgins,and Sgt. Ralph W. Bottreil. At the beginning of1919, energetic Major E. L. Hoffman was chosenas military head of this parachute developmentteam.

The “crash program” produced results.Parachutes from all over the world, all attached(static-line actuated) types, were tested and foundto be unsafe and weak, and otherwise unsuitable

for use in emergency jumps from airplanes. Initialtesting on a new parachute design devised byFloyd Smith showed potential. This conceptinvolved the use of a parachute canopy and linespacked into a container worn on a body harness,using a manually operated ripcord, yanked whilefalling freely through the air with no attachmentto the aircraft, to open the parachute. FloydSmith, with Guy Ball working closely at his side,worked together to perfect this new revolutionaryparachute.

This parachute ultimately became the U.S. AirService Airplane Parachute, type A. It had a28-foot diameter silk canopy with silk suspensionlines. The canopy was formed of 40 gores, witha novel shock-reducing vent design, and it waspacked into a backpack container worn on thebody of the flyer, by being attached to a webbingharness. A small pilot-chute was used to deploythe packed canopy and lines into the air when apull on the ripcord opened the flaps on the backcontainer being worn on the body. Not beingdependent on any attachment to the aircraft foroperation, it allowed the aviator to leave hisdisabled aircraft regardless of its position. It wascapable of withstanding an opening shock de-livered by 200 pounds falling at a speed of 400miles per hour.

When Major Hoffman felt that it was time forthe Model A parachute to be live-jumped, hechose a young, enthusiastic parachutist anddesigner named Leslie L. Irvin because of his vastexperience as a parachute jumper. Irvin hadresponded to the government’s call for a suitableparachute, and submitted a static-line operatedparachute assembly with a cotton canopy. He wasapprised that the submitted parachute wasunsuitable because by that time the use of a silkcanopy, as well as the ripcord concept, wasconsidered preferable. Irvin continued tocooperate with the board by supplying parachuteitems. On April 28th, 1919, flying in a USD-9airplane piloted by Floyd Smith at an altitude of1,500 feet and airspeed of 80 miles per hour, Irvinjumped from its turret cockpit wearing a proto-type Model A chute. He pulled the ripcord,the parachute opened in one and two-fifthseconds, and he became the first man to make afree-fall parachute jump from an aircraft.

The new parachute was the first step on theway to all modern personnel parachutes—emer-gency, military, and sporting. From this basicdesign came the seat pack, chest or reserve chutes,backpacks, and any other parachute that can beattached to a harness.

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In October 1922, Lieutenant Harold Harris,U.S. Army, was dramatically saved from deathby using a manually-operated parachute when hisaircraft failed. By March 1924, it becamemandatory for all Army and Navy aircrew to wearthe standard back-type parachute while in flight.A sign in one of the parachute lofts read, “Don’tforget your parachute. If you need it and youhaven’t got it, you’ll never need it again.”

With the requirement for all Navy aviators towear parachutes, the necessity for trained per-sonnel to pack and maintain these parachutesbecame apparent. In June 1922, the Bureau ofAeronautics requested volunteers from among thepetty officers attached to the various naval airstations to take a course of instruction inparachutes at the Army School at Chanute Field,Rantoul, Illinois. Thirteen chief petty officerswere selected from throughout the Navy. Theycompleted the course of instruction and returnedto their duty stations. Three of them were selectedfor further training at McCook Field, Dayton,Ohio, at that time the Army Equipment Experi-mental Depot. The three chief petty officersreceived advanced training in parachutes. InAugust 1923, Chief Alva Starr and Chief LymanFord, two of the three, were ordered to Lakehurst,New Jersey, to set up a training course onparachutes. Although the course was established,the PR rate was not established until 1942. In

September 1924, class No. 1 was convened at theParachute Material School at Lakehurst to teachparachute rigging.

Although his name is now lost to history, oneof the farsighted founders of the PR schooldecided on a novel means to help combat theairmen’s reluctance to “hit the silk.” He reasonedthat if it became known that the men who packedand repaired the parachutes had enough confi-dence in their ability and equipment to makea deliberate, premeditated jump, the aviator mightbe more willing to take a chance on his parachutethan to crash in his airplane. In the beginning,graduate trainees jumped from the outer wing tipsof a biplane flying high above the naval air stationat Lakehurst. Later, the students “let go” fromshort rope ladders suspended from the sides ofthe old gondola airships (blimps), and later still,from training and patrol type lighter-than-airships. Since the beginning of the PR school in1924, there have been over 72,000 parachutejumps made at Lakehurst, New Jersey.

With the coming of the jet age, the emergencyuse of parachutes has become a highly technicalsequence; that is, events in time order. Today’semergency sequence for ejecting from a disabledaircraft starts with the aircrewman making adecision to leave the aircraft. After making thatdecision everything is done automatically, as youwill see in the ejection sequence for the A-6aircraft, shown in figure 1-1. This is only one of

Figure 1-1.—Ejection sequence.

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several types

Figure 1-2.—Aircraft egress, pilot chute deployed, and main canopy free of container.

of ejection systems used in modernnaval aircraft. For example, the ejection sequenceof the Mk GRU-7 is as follows:

1. Initial ejection.2. Drogue gun fires.3. Controller drogue deploys.4. Stabilizer drogue deploys.5. Main parachute deploys and a normal

parachute descent is made.

From the experimental devices of the earlyChinese through the seat ejection systems oftoday, you can view the evolution of theparachute. If you consider this development asa window through which you can see solutionsto the escape problems of the fliers of the spaceshuttle or other advanced craft, then this historyis just the end of the beginning.

A parachute appears somewhat similar to agiant umbrella. By offering a large air-resistingor drag surface, the parachute, when opened,provides the deceleration necessary to allow for

the safe descent of an aircrewman. In eachparachute jump a sequence of events, shown infigure 1-2, takes place. After the parachutist clearsthe aircraft, he pulls the ripcord. The ripcord pinsare removed from the locking cones, permittingthe grommets to separate from the locking cones.The container spring opening bands pull the sideand end flaps apart allowing the pilot chute tospring beyond the negative pressure area im-mediately above the falling body. This resultsin its getting a better “bite” on the surroundingair, thus speeding the opening of the canopy.

The aircrewman falling away from the pilotparachute causes the main canopy to be pulledfrom the container assembly, followed by thesuspension lines. The canopy begins to fill withair during this operation.

The ties on the risers break as the load isapplied. The lift webs are then pulled from thecontainer while the canopy fully opens; at thispoint the parachutist receives the opening shock as

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the parachute fills with air. The aircrewman thenhangs or sits suspended in the harness during thedescent.

There are many different types of parachutesused in today’s naval aircraft. To really under-stand the operating principles of a parachute, youshould first know the basic design and construc-tion of a parachute and its components.

COMPONENTS OF PARACHUTES

The design and construction of a parachuteand its components are based on the old idea thata chain is only as strong as its weakest link. Every

component, or link from the jumper to the canopymust carry its share of the maximum load thatis applied during the opening shock.

The five major parts of a standard serviceparachute, starting at the top and working down,are the pilot chute, main canopy, suspension lines,harness, and pack. These five major parts areshown in figure 1-3.

PILOT CHUTE

The pilot chute has the job of anchoring itselfin the airstream, then pulling the remainingpacked components out of the parachute pack.The order of deployment for most parachute

Figure 1-3.—The five major parts of a parachute.

1-5

Figure 1-4.—Pilot chute.

assemblies is the pilot chute, the canopy, thesuspension lines, and the risers. A typical pilotchute is shown in figure 1-4.

CANOPIES

Five sizes of canopies are used in navalaviation. They are the 35-foot, 28-foot, 26-foot,24-foot, and 17-foot sizes. The 28-foot canopy isthe size dealt with in this chapter and is most

commonly described as a polygon, having 28sides, and a diameter of 28 feet plus or minus 1inch. The 28-foot canopy contains approximately796 square feet of nylon cloth, plus 2,400 yardsof nylon thread. The sewing on a parachute variesfrom 8 to 10 stitches per inch. The cloth that isused in the construction of a parachute canopyis high-tensile strength, 1.1 ounce ripstop nylon.Ripstop nylon cloth must meet the followingminimum requirements: tensile strength—42

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pounds per square inch; tear strength —5pounds; air permeability —80 to 100 cubicfeet per minute.Tensile strength is the greateststress cloth can withstand along its lengthwithout rupturing, expressed as the number ofpounds per square inch. Tear strength isthe average force, expressed in pounds, re-quired to continue a tear across either thef i l l ing or the warp o f the c lo th . A i rpermeability is the measured amount, in cubic

feet, of the flow of air through a square foot ofcloth in 1 minute under a specific pressure.

The suspension lines are sewn into the canopy.These lines run continuously from the connectorlink on one side, through the canopy, and to theconnector link on the other side (fig. 1-5). Thematerial between any two suspension lines is calleda gore. There are 28 gores in a 28-foot canopy.Each gore is composed of four sections identified

Figure 1-5.—Suspension lines on 28-foot canopy.

1-7

Figure 1-6.-Close-up view of a gore.

by the letters A, B, C, and D (fig. 1-6), startingwith the bottom section. Figure 1-7 is a flat viewof the entire canopy, and the note in the figureshows the relationship of the gore in figure 1-6to the rest of the canopy.

Most woven cloth has two types of threads—warp and filling. These two types are identifiedby their relationship to the selvage edge. A selvageedge is a finished edge on two sides of a piece offabric to prevent raveling. This finished edgesometimes has a narrow border of differentthreads or sometimes it may have a differentweave. Warp thread runs parallel to the selvageedge of cloth and runs lengthwise down a roll offabric. Filling thread runs perpendicular to theselvage edge or crosswise across the width of thecloth.

The sections used in a parachute canopy arecut at a 45-degree angle to the centerline of thegore. This is called a bias construction andprovides the maximum strength and elasticity. Theradial and diagonal seams are double lapped forsecurity. The suspension lines are enclosed in thechannel produced by stitching the radial seams.Figure 1-7 shows a flat view of this biasconstruction of the 28-gore canopy. Stenciled onthe top center gore (section A of gore 28) in lettersone-half inch high and about 12 inches from thebottom of the canopy are the NAVAIRFAC ordernumber, date of manufacture, serial number, andthe manufacturer’s mark or trademark. Stenciled

on the diametrically opposite gore (section A ofgore 14) is the date of manufacture and serialnumber.

If you should have to add markings to thecanopy, the marking fluid you use should be inaccordance with Specification MIL-I-6903A,Amendment No. 1.

Note the vent pictured in figure 1-8. This ventacts as a relief valve and relieves the high internalpressure within the parachute at the instant ofopening. Without this vent, an opening at highspeed could result in a dangerous rupture of thecanopy. The skirt (not shown) and vent hems arereinforced with 1-inch tubular nylon webbing witha tensile strength (T/S) of 4,000 pounds, to aidin preventing tears from completely separating thecanopy.

All machine stitching, except zigzag, shouldconform to Type 301, Federal Standard 751, andshould be not less than 8 nor more than 10 stitchesper inch. Ends of all tape, webbing, and lines mustbe seared to prevent fraying. No waxes should beused. For sewing diagonal seams, either size B orE nylon thread may be used. Use size E threadfor all other seams, zigzag stitching, and repairs.

Removable connector links provide a quickattachment for the canopy and suspension linesto the lift webs.

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Figure 1-7.—Flat view showing bias construction on a 28-foot canopy.

Figure 1-8.—Vent.

1-9

NOTE: To determine the service life of aparachute component, refer to the Mainte-nance Requirement Cards, NAVAIR13-600-4-6-3.

SUSPENSION LINES

The suspension lines form a net or skeleton forthe canopy and absorb much of the shock load.Therefore, when being assembled, they must beplaced under a 20-pound tension, marked, and cutas a group to assure equal distribution of the shockload. The 28 suspension lines counted at the linksare actually 14 lines, 75 feet 4 inches in length.These lines run continuously from link to link;that is, each line is secured to a connector link onone side of the canopy, runs up and over thecanopy, and down to a link on the opposite side.

Type III nylon suspension line (with a mini-mum tensile strength of 550 pounds) is used on allmain canopies and vane-type pilot chutes. Thisline consists of a loosely woven outer coveringcalled a sleeve, and several strong inner cordscalled the core. This core provides the greaterportion of the strength of the suspension line.

The suspension lines are attached to the con-nector links by tying a clove hitch, then a half-hitch, and completing the attachment with2 (±1/2 or – 1/4) inches of zigzag stitching.These lines are attached to the lift webs withremovable connector links. One of the fourremovable connector links is shown in figure 1-9.See the four links (the ends of the suspension lineswithout the lift webs) in figure 1-5.

To prevent the canopy on the 28-foot para-chute from slipping along the suspension lines,each line is anchored by zigzag stitching at severalpoints to the radial seams through which it passes.One-half inch of slack is allowed in the vicinityof the skirt between the zigzag sewing points torelieve the strain during opening shock.

PARACHUTE CONTAINERS

The parachute container is designed to houseand protect the pilot chute, main canopy, andsuspension lines. There are as many differentstyles of containers as there are parachutes. Theyall have the same basic opening procedures. Thereare four flaps: top, bottom, left, and right. Theseflaps are held closed by two or four ripcord pinsinserted through locking cones. To open theparachute container, the ripcord pins must beremoved either manually or automatically. Thisallows the flaps to open and the pilot chute tospring from the pack. The pilot chute then pullsthe canopy out.

Figure 1-9.—Method of attaching suspension lines at thelink.

PARACHUTE HARNESS

The harness is the part of the parachute thatholds the parachute to the wearer. It is designedto absorb the largest part of the opening shock,with chest, leg, and back straps added to preventthe jumper from falling free from the chute onthe way down. Personnel parachute harnesses aremade of 1 3/4-inch-wide nylon webbing, whichhas a tensile strength from 6,000 to 8,700 pounds.

The Navy uses two types of harnesses. Thefirst is the quick-fit harness. It is made in threeconfigurations: seat-type, back-type, and chest-type. The other type of harness is the integratedtorso harness. It combines the harness, lap belt,and shoulder harness into one integrated garment.This harness improves the individual’s comfortand mobility; it is more secure and is easier to puton and take off. It also reduces the number ofexposed straps and overall bulk and weight.

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RIPCORDS HARNESS HARDWARE

The ripcord is a manual releasing device usedto allow the container to open. It consists oflocking pins securely attached to a length of3/32-inch diameter corrosion-resistant steel cable.The ripcord handles are made of steel tubing inthe shape of a cloverleaf or a trapezoid, and theyare attached by passing the cable through a smallhole drilled in the grip and then swaging aretaining ball or clamping a small sleeve onto theloose end of the cable. The pins are swaged inplace and tested to withstand a pull of 300 pounds.

Parachute harness fittings (hardware) aresmall metal devices usually made of cadmium orchrome-plated steel. They are designed to join theparachute and harness and to afford easy andrapid adjustment of the harness to the wearer.

The many types of parachute harness fittingsinclude adapters, snaps, D-rings, V-rings, con-nector links, and Koch release adapters. Someof the more common types of these fittings andtheir tensile strengths are illustrated in figure1-10.

Figure 1-10.—Harness hardware (page 1).

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Figure 1-10.—Harness hardware (page 2).

ADAPTERS SNAPS

There are several types of snaps used withparachutes. They are the plain harness snap, thequick-fit snap, and the quick-connector snap. Theharness snap is a plain hook-shaped, spring-actuated guard, which snaps over a V-ring tosecure two parts of the harness together. Thequick-fit snap is similar except that it has a gripslide bar. The quick-connector snap is similar to

Two types of adapters are used with aregular quick-fit type harness. They are theregular harness adapter and the friction adapter.The harness adjuster adapter is used to adjustthe harness to the wearer, and the frictionquick-fit adapter has a grip slide bar, whichallows the wearer to make quick adjustments tothe harness.

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the harness snap and is used as a means to quicklyattach the Navy chest-type parachute to the twoD-rings on the Navy chest-type harness.

CONNECTOR LINKS

Connector links are fittings designed to jointhe parachute to the harness. The suspension linesare attached to one side and the harness to theother connector links.

KOCH RELEASE ADAPTERS

Integrated torso suit harnesses are equippedwith four Koch release adapters, which attach tothe fittings on the lap belts and risers of theintegrated parachute assembly. Release fittingadapters are manufactured in two parts-maleand female.

The male portion of the adapter is attachedto the torso suit harness, while the female portionis attached to the riser assembly of the parachute.Figure 1-11 shows the Koch parachute releaseadapters.

NOTE: Aircrew Systems Change 446incorporates the “parachute harnesssensing release unit,” commonly referredto as SEAWARS. SEAWARS is designedto automatically release the parachuterisers upon immersion in seawater.

TRANSPORTING PARACHUTES

When issuing parachutes you may need togive some instructions to the aircrewmen onproper ways to carry and handle them. Themost effective way to explain the proper handlingof packed parachutes is to list a series of DO’sand DON’T’s.

1. DO NOT pick up a parachute by itsrisers or ripcord. Lift web tackings breakrelatively easily, and when they do, the sus-pension lines are almost certain to becomedisarranged.

2. DO NOT allow a parachute to come incontact with light fixtures or heat sources.Heat tends to decompose the fabric.

3. DO take EVERY precaution to pre-vent soiling or contaminating parachute as-semblies.

4. DO NOT stack parachute assemblies ontop of each other or on the floor, unless they arein suitable shipping containers.

5. DO NOT leave a parachute whereheavy objects can be dropped or placed onit. Permitting a parachute to be carried ina cargo net along with squadron cruise boxesor similar gear is an example of poor handlingtechniques.

6. DO use utmost CAUTION when handlingparachute assemblies with installed cartridge-activated devices.

7. DO NOT tack or tie a container with theparachute in the packed condition.

8. DO clean thoroughly vehicles usedto transport parachute assemblies. DO checkfor contamination and provide with suitablecovers during inclement weather.

SHIPPING CONTAINERS

Figure 1-11.—Koch release adapters.

Parachutes are shipped and/or stored insealed shipping containers of either card-board or metal construction and of suitablesize. The containers are designed for reuse,and they must be opened and closed withcare.

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When you are using the container to returnparachutes to supply or to transfer the assemblyto another activity, ensure that th eold tags andlabels on the container are removed or markedout. Ensure that the proper tags and labels areattached and properly filled out on the trans-ferring container. Tags and labels are shown infigure 1-12.

STORING

To place a parachute assembly into temporarystorage, proceed as follows:

NOTE: This procedure is for parachuteassemblies that are in a ready-for-issue(RFI) status only.

1. Inspect the parachute assembly, ensuringthat it is in an RFI status. Check the nameplateinformation with the recorded information on theparachute history card. Fill out an AircraftEquipment Condition Tag, indicating the as-sembly name, serial number, and part number.

2. Remove and disarm the automaticactuator. (This is an explosive device used toautomatically pull the ripcord on certainparachutes.)

3. Remove cartridges from all other car-tridge-actuated devices (these are other explosivedevices used to assist in opening certain types ofparachute canopies). Store the cartridges fromexplosive devices in accordance with existinginstructions.

4. Release all snap fasteners, open all slidefasteners, and remove one end of each of theparachute container spring opening bands.

5. Chain the parachute suspension lines.6. Remove the manual ripcord cable as-

sembly and place it in a small paper or plastic bag.7. Examine the shipping container for con-

dition. Remove or mark out all old tags or labelson the container.

8. Place the ripcord assembly in a sidepocket of the parachute bag or at the bottom ofthe container. Spread one-eighth pound ofnaphthalene flakes on top of the parachutecontainer. Insert the suspension lines loosely andfold in the canopy; then sprinkle one-fourthpound of naphthalene flakes into the canopy fold.Lay the pilot parachute into the shipping containeruncompressed.

9. Close the shipping container; if a card-board box is used, tape the flaps closed.

10. Place the parachute into storage accordingto local requirements.

PERSONNEL PARACHUTEINSPECTIONS

As a PR you have one of the most importantjobs in naval aviation. The type of equipment youwill be working with is lifesaving equipment.Unlike the other components that make up thenaval aircraft, the parachute has no backupsystem. If all other parts fail, the parachute mustfunction to prevent serious injury or death to theaircrewman.

Parachutes are primarily designed to allowpilots and aircrewmen to escape from disabledaircraft. The nature of this lifesaving system leavesno margin for error in the work of the PR.Parachute inspections must be carefullyconducted, ensuring security, rapid positivefunctioning, airworthiness, and comfort of theentire assembly.

Procedures for working with parachutes aredifferent from other types of work becausewhenever a critical operation is performed, therigger’s work must be inspected and his per-formance verified and recorded by a designatedinspector before work continues. Continuing witha procedure without obtaining the requiredinspection is prohibited. Although this constantinterruption of work may seem inefficient, youmust appreciate how important it is to theparachute user that every step is done exactlyright.

REASONS FOR INSPECTINGPARACHUTES

Depending on its use, a parachute is exposedto a large number of potentially destructive forcesand agents. A parachute consists of many partsand is a complex and sometimes fragile assembly,so there are many chances for something to gowrong. Once a parachute has been inspected,repacked, and placed in service, it is movedaround, sat on, leaned against, and in many wayssubjected to forces that can cause chafe and wear.When installed in an aircraft or being worn, theparachute may be contaminated by a number ofpotentially harmful fluids such as perspiration,lubricants and hydraulic fluids, chemicals, andsalt water. Dampness can also get into thecomponents from humid conditions.

Aside from inspecting for damage, newparachutes are inspected before being placed inservice because it is possible for a mistake to bemade when many persons are involved in amanufacturing process. A parachute may also

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Figure 1-12.—Shipping tags and labels.

require changes and modifications. These are As you can see, many things can happen toissued by the Aircrew System Bulletins, Aircrew a parachute in service. Inspection schedules basedSystems Changes, and updated material entered on experience are established to ensure thatin the Emergency Personnel and Drogue damage is detected before it becomes serious.Parachute Systems Manual, NAVAIR 13-1-6.2. You have the responsibility of following these

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schedules and for properly doing the requiredinspections.

INSPECTION SCHEDULES

The frequency and nature of parachuteinspections depends on the use of the parachute.Those used regularly for jumping, such asparachutes assigned to SEAL teams, are inspectedand repacked after each use; these and others areon a different schedule than those intended foremergency use. Our discussion focuses on emer-gency parachutes to emphasize that althoughthey are rarely used, they may be damaged inhandling or exposed to hazards in theirenvironment.

Emergency parachutes are assigned to oper-ating units. They may be part of an aircraftinventory or they maybe assigned to a ready issueroom. To some extent, the frequency of theirinspection depends on the type of aircraft to whichthey are assigned. Those assigned to attack orfighter aircraft are inspected more frequently thanthose on the larger patrol, cargo, or other planeswhere they are not sat upon or otherwise subjectedto as many hazards.

Major inspections of emergency parachutesare routine when the parachute is first put intoservice, and then later at intervals to coincide withthe time the aircraft is down for major main-tenance.

Less extensive inspections that do not involveunpacking the parachute are daily, preflight,postflight, and special. These special inspectionsare done every 7 days, 10 days, or 14 days,depending on the type of aircraft. Of course, ifany damage is found or suspected during theseinspections, the assembly is sent to an aviationintermediate maintenance depot (AIMD) forthorough inspection, testing, and possible repair.

Several special inspections may also be done.For instance, after a combat mission theparachute assembly is inspected for missiledamage from bullets or fragments. After anemergency use the entire parachute is shipped tothe Naval Weapons Center, China Lake, Cali-fornia, for a detailed inspection. Other in-spections may be ordered if defects are suspectedin a group of parachutes or in association withauthorized changes and modifications.

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PARACHUTE MAINTENANCE

All parachutes are given periodic main-tenance inspections under the direction andcontrol of the maintenance control officer.Maintenance is to be thorough at all times.No instance of careless treatment or neglectof parachute equipment is to be allowed topass unnoticed. The vital function of thisequipment must be uppermost in the minds ofall personnel concerned.

SPECIFICATIONS

Parachute maintenance and inspection pro-cedures are performed according to the guide-lines set forth in the Emergency Personneland Drogue Parachute Systems Manual,NAVAIR 13-1-6.2, and the M a i n t e n a n c eRequirements Cards, NAVAIR 13-600-4-6-3.These manuals are continually updated, andwhen using them, as in using any publica-tion, you must first make sure that thecurrent changes are included. The manualswill list all of the proper steps, procedures,and points to inspect. They also give youinformation about proper specifications, tech-nical data, and are used to ensure thatall steps are followed, all details are in-spected, and that all quality control itemsare checked at the proper time by a qualityassurance inspector (QA). Using these manualsis mandatory and ensures that you are follow-ing the current and approved procedures.

Whenever a question on the constructionof parachute equipment comes up, you shouldobtain and study the drawing that applies.Repairs that are difficult should be comparedto the drawing to ensure that the finishedproduct is the same as the one in the draw-ing. The drawing number or reference numberof a particular piece of parachute equipmentcan be found in the applicable work packagein the Emergency Personnel and Drogue Para-chute Systems Manual, NAVAIR 13-1-6.2.

All parachute maintenance is done bythe lowest level activity equipped to satis-factorily perform the work. Mission, time,equipment, trained personnel, and operationalneeds are the basic considerations involvedin determining which level performs thework.

PARACHUTE INSPECTION ANDMAINTENANCE RECORDS

The following records and documents are usedby the Aircrew Survival Equipmentman, underthe direction of the maintenance control officer,to provide a systematic means of control.

PREFLIGHT/DAILY/TURNAROUND/POSTFLIGHT MAINTENANCERECORD (OPNAV 4790/38)

Whenever you perform any of these rou-tine inspections you must fill out an OP-NAV Form 4790/38 (fig. 1-13). You alsouse this Preflight/Daily/Turnaround/Postfight

Maintenance Record Card to record thespecial (7- or 14-day) inspection in accordancewith applicable Aircraft Maintenance Require-ment Card decks and OPNAVINST 4790.2(series).

PARACHUTE CONFIGURATION,INSPECTION AND HISTORYRECORD (OPNAV 4790/101)

The Parachute Configuration Inspection andHistory Record is designed to provide acontinuing historical record of a parachuteassembly and its components throughout its

Figure 1-13.—Preflight/Daily/Turnaround/Postflight Maintenance Record, OPNAV 4790/38.

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Figure 1-14.—Parachute configuration inspection and history record.

service life (fig. 1-14). The form is a two-part NCR of all history records, including the currentform. The hardback copy is to be filed in the hardback copy, is maintained as designated by theaircraft logbook for the aircraft in which the cognizant aircraft maintenance officer for spareparachute is installed. All original (flimsy) copies parachute assemblies; upon installation of theof the history record are maintained in a spare parachute into an aircraft, the hardbackpermanent file as designated by the cognizant copy is transferred to the appropriate aircraftaircraft maintenance officer. A permanent file logbook. Upon transfer of the aircraft or

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parachute assembly from one activity to another,all original (flimsy) copies from the permanent fileare transferred to the new custodian to providea complete history of the parachute assembly.This will also initiate the new custodian’spermanent file. When a parachute assembly hasbeen involved in an aircraft accident, the historyrecord and the permanent file of original (flimsy)history records are forwarded to the Commander,Naval Weapons Center (Code 64123), ChinaLake, CA 93555.

Initiation

The IMA placing the parachute assembly intoservice initiates the Parachute ConfigurationInspection and History Record. The IMA initiatesa new history record each time the parachuteassembly is inducted for repack or maintenance.All required entries must be legibly recorded,using a ball-point pen or typewriter. The AircraftBuno/Serial Number block maybe annotated inpencil or left blank, to be filled in by the cognizantcustodian of the parachute assembly. Entry errorsare ruled through a single line and initialed by thequality assurance inspector. The hardback copyfrom the previous inspection can be destroyedupon acceptance of the newly repacked parachuteassembly by the OMA.

The type parachute (NES-12, A/P28S-27), theparachute assembly part number (576AS100-27,MBEU 10030PA-4), the canopy serial number,the date the canopy was placed in service (monthand year), the aircraft buno/serial number, thecontrolling custodian’s alphanumeric 3-M organi-zation code, the next scheduled removal date(Julian date), and the actual removed date (Juliandate) must be entered at the top of the historyrecord.

Cartridges and Cartridge-ActuatedDevices

The parachute in the example uses a cartridge-actuated device, so you must fill out theappropriate columns on the history card. If theparachute does not use the devices listed, you mustuse the letters N/A (not applicable) in thecolumn(s). Enter the part number, type ofcartridge being used, the time delay of thecartridge, lot number, and the expiration date ofthe cartridge.

Technical Directives

Since you are placing the parachute intoservice, you must update its history of technicaldirectives with prescribed changes and modi-fications that were previously incorporated. Thecodes used to properly fill out this part of thehistory card can be found in appendix K ofOPNAVINST 4790.2 (series). You also need touse NAVAIR 13-1-6.2 to find a listing of alltechnical directives that apply to this equipment.

Miscellaneous History

If applicable, you should enter the results ofthe ripcord pin pull force check for bothdisassembly and assembly. Notice the qualityassurance inspector’s initials are entered beloweach recorded measurement. The inspector’sinitials must also be placed in the space followingthe Suspension Line Mandatory Inspection Point(SLMIP). If applicable, the automatic parachuteripcord release firing altitude and the results ofthe spreading gun firing pin pull force check arelogged in the proper location. If these checks donot apply, you should enter N/A. You shouldenter the Julian date of the last completeinspection and repack, if applicable. If you findthese actions are not applicable, enter N/A.Indicate whether or not a canopy damage chartis attached by checking the appropriate box.

Configuration Verification (A list ofeach item that has a service life)

All parachute components other than car-tridges and cartridge-actuated devices withassigned service life must be entered in theConfiguration Verification Section of the historyrecord. Service life items can be identified byreferring to the Illustrated Parts BreakdownNumerical Index of the applicable parachuteassembly work package. Enter the nomenclature,part number, contract number, manufactureddate (month and year), placed-in-service date, andthe expiration date for each component with aservice life. Obtain the date of manufacture andcontract number from the component label. Theplaced-in-service date is from the date the shippingcontainer seal is broken. If the service life has beenextended for a particular component, enter theissuing authority and the date-time group of theauthorizing message in the Remarks column. Ifthe contract number is not known or cannot bedetermined, enter UNK in the appropriate block.

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After the parachute assembly has been repaired,inspected, and repacked, and the packer andinspector are satisfied the parachute assemblyis ready for flight, the packer and qualityassurance inspector must legibly sign theirfull names and rates, QA stamp in theinspector block, and enter the date and 3-Morganization code of the IMA at the bottom ofthe history record. The stamp must not obscurethe signatures.

Procedures

Upon transferor the parachute, the currenthardback copy and all original (flimsy) copies inthe permanent file are forwarded to the newcustodian to provide a complete history of theentire service life of the assembly.

When a parachute has been involved in anaircraft accident, the record is forwarded inaccordance with OPNAVINST 3750.6.

Figure 1-15.—Canopy damage chart for 28-foot diameter canopy (page 1).

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When a parachute (canopy) has been retiredbecause its total service life has expired, the recordmay be destroyed. Subassemblies for which thetotal service life has not expired may be salvagedfor future use. Appropriate service life in-formation is transcribed to an Aircraft EquipmentCondition Tag (NAVAIR-2650) and attached tothe salvaged items if they are to be reused. Underno circumstances should a salvaged item be reusedif its previous history cannot be firmly established.

CANOPY DAMAGE CHARTS

Whenever a canopy is inspected and found toneed repairs, an appropriate Canopy DamageChart must be filled out. An example of this chartis shown in figure 1-15. The symbols to be usedare shown on one side of the chart. As each defectis repaired, you write the letters “OK” in thesection representing the respective gore. If repairscannot be made locally, the chart goes with the

Figure 1-15.—Canopy damage chart for 28-foot diameter canopy (page 2).

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canopy to the next higher level maintenanceactivity. This form must not be discarded. Whenthe repairs are done, the Canopy Damage Chartis attached to the Parachute Configuration,Inspection, and History Record.

NAVAL AVIATION MAINTENANCEPROGRAM FORMS

The following forms used in the NavalAviation Maintenance Program (NAMP) areapplicable to parachute maintenance: VIDS/MAFForm, Support Action Form, and DoD SingleLine Requisition System Document. Propercompletion of documents is essential to thefunction of the program. Detailed instructions ontheir use may be found in the Naval AviationMaintenance Program Manual, OPNAVINST4790.2 (series).

RECORDING MODIFICATIONS

When a modification is performed on aparachute assembly, you must record the assignedtechnical directive code and modification code onthe Parachute Configuration, Inspection andHistory Record. Other records must be completedin accordance with OPNAVINST 4790.2 (series).

INSPECTIONS

The various times at which inspections areperformed on personnel parachutes are discussedin the following paragraphs.

DAILY INSPECTION

A daily inspection should be performed on allin-service parachute assemblies either installed inaircraft or in ready issue rooms. The inspectionmay be accomplished by line personnel, or by anissue room custodian who has been checked outby both the AME and PR shops and foundqualified. The inspection is performed inaccordance with the MRC for the equipment andthe requirements detailed in NAVAIR 13-1-6.2 forthe aircraft involved. It is done before daily flightoperations and is a visual in-place inspection. Itis also included in the special (7- or 14-day)inspection.

The packaged parachute is inspected forexternal evidence of damage. You should belooking for wear or other evidence of physicalabuse. The assembly should also be checked for

stains, which may indicate contact with harmfulfluids or chemicals. Any stain should be con-sidered harmful until the fluid that made it isidentified. Stains or discolorations may also becaused by contact with a hot object. Heat canseriously weaken the synthetic fabrics in parachuteassemblies. Another possible source of trouble isexposure to ultraviolet radiation such as sunlightor some types of artificial lighting. Any evidenceof damage or suspicious condition must bereported to maintenance control.

SPECIAL INSPECTION

The special inspection is performed at intervalsof 7, 10, or 14 days, depending on the type ofaircraft. In-service parachute assemblies installedin aircraft and in ready issue rooms are also giventhis special inspection. This inspection includesthe integrated torso harness and quick attachableharnesses. The daily inspection is included as partof performing the special inspection. Assembliesused for training, parachute rescue, pathfinding,and reconnaissance teams, and those parachuteassemblies not assigned to a specific type ofaircraft are inspected every 14 days. It is done byorganizational level maintenance PR personnel,such as yourself, and conducted only underadequate lightning conditions.

This inspection includes, but is not limited to,emergency aircraft escape assemblies and/orsystems, as well as assemblies used for pre-meditated free-fall or static line parachutedescents. The reserve (emergency) parachute,which may form a part of a training-type, troop-type, or a test assembly, is also inspected.Parachute assemblies are not opened for thespecial inspection or for the daily inspection. Ifyou find or suspect any damage or contamination,notify maintenance control. When you completethe special inspection, enter your full name, rate,and current date on the Preflight/Daily/Turn-around/Postflight Maintenance Record Card.

ACCEPTANCE (ORIGINAL ISSUE)CALENDAR/PHASED/CONDITIONALINSPECTIONS

The acceptance (original issue)/calendar/phased/conditional inspection is performed at thelowest level of maintenance possible. Theseinspections include, but are not limited to, aircraftemergency escape assemblies and/or systems.

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Original Issue/Acceptance

The original issue inspection is performed atthe time a parachute is placed into service. Theoriginal issue inspection consists of a visualinspection of the assembly and a repack of theparachute assembly in accordance with theapplicable work package. When a parachuteassembly is an aircraft inventory item, theacceptance inventory inspection serves as theoriginal issue inspection. In this case, the packedparachute assembly is visually inspected fordamage, and the records concerning the parachuteare examined for discrepancies or missing in-formation. If any discrepancy is found, aconditional inspection, which includes a repackof the parachute assembly, is performed.

Calendar/Phased

The regular inspection cycle of a parachuteassembly should correspond either to the aircraftcalendar inspection or to the phased maintenanceinspection cycle program, as directed by NAVAIR13-600-4-6.3. You should ensure the parachuteassembly inspection period does not expire beforethe scheduled maintenance period of the aircraft.To meet unusual situations and facilitate work-load scheduling, a plus or minus 1 week, orportion thereof, may be applied to the authorizedinspection interval. To enable a ferry flight toreturn to home station/ship after an away fromhome grounding discrepancy of such duration thatinspection interval expired, necessary additionaldays maybe added. However, in each instancedeviations apply only to the immediate inspectiondue. If unusual circumstances dictate deviationsof succeeding inspection intervals, each deviationmust be computed from the date on which theinspection would have been due if the precedingdeviation had not been granted.

Conditional Inspection

When a parachute assembly must be inspectedas the result of a specific situation or set ofconditions unrelated to the normal inspectioninterval, a conditional inspection is performed.

Postcombat Inspection

Organizational-level maintenance inspectsparachute assemblies for external damage orabnormal condition after each combat mission.When an aircraft has been subjected to gunfire,

all parachutes are examined for damage prior tothe next flight. If bullets or fragments haveentered the parachute assembly, you must removeit from service and perform a conditionalinspection.

Aircraft Accident Report Inspection

Any personnel parachute, along with relatedsubassemblies or equipment (pilot parachutes,stabilization parachutes, containers, harnesses,cushions, automatic parachute ripcord releaseassemblies, ballistic spreading guns), that has beenrecovered following use in an emergency bailoutor ejection must be returned to the nearest navalsupply activity for shipment to the CommandingOfficer, Naval Weapons Center (NWC), ChinaLake, California. The parachute must be in thesame condition that it was when recovered. Donot chain the lines. You do this in the event thatan engineering investigation is necessary by NWC.Stencil on the outside of the shipping containerin 1 - inch le t ters the fo l lowing : “THISEQUIPMENT HAS BEEN USED IN ANEMERGENCY SITUATION.” These items arerequired so that a design deficiency can bedetected, or to establish requirements for productimprovements.

OPNAV 3750.6 gives procedures you mustfollow to provide the Naval Weapons Center withsufficient information to properly evaluate andimprove these parachutes for service use. Inaccordance with this instruction, you will giveNWC the following information:

1. Name of submitting activity and AARnumber

2. Date, time, and place of use3. Name, rank/rate, serial/service number of

user4. Model aircraft, altitude, attitude, airspeed,

and sink rate at time of ejection or bailout (ifknown)

5. Type of parachute and serial number ofcanopy assembly

6. Type and model designation of ejectionseat (if applicable)

7. Type of automatic parachute ripcordrelease and serial number

8. A brief narrative summary of anydifficulties with the personnel parachuteequipment and/or automatic actuator or otheradditional information that may be applicable

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Also include the Parachute Configuration,Inspection, and History Record and any referenceinformation or documents that would have abearing on a technical investigation. If theaircrewman sustained fatal or serious injuriesduring the escape or recovery sequence, includephotographs of the parachute, ejection seat, andother components at the scene of the impact.

Ensure the proper shipping tags and labels areattached to all equipment and the shippingcontainer. If pyrotechnics or explosives are in thepackage, it should be noted on the outside of thec o n t a i n e r .

PROCEDURES FOR PRELIMINARYTESTS AND INSPECTIONS

When you are assembling a parachute for anoriginal issue inspection or performing a normalcalendar repack, you will have to do somepreliminary test and inspections that are commonto all personal parachutes. These inspections andtests are discussed in the following text.

RIPCORD PULL TEST

Parachutes must be given a ripcord pull testbefore being unpacked for inspection. Themaximum pull force that you may use is 27pounds. If you go over 27 pounds, the ripcordpins, cones, and grommets must be checked forbends, dents, and roughness, and make sure thatthe ripcord cable moves freely in the housing.Inspect the housing for sharp bends or dents andreplace any damaged parts. Silicone spray maybe sparingly applied to ripcord parts. Make surethat ripcord pins are properly positioned beforetesting. All assemblies with metal ripcord handleclips require an additional test. To do this, usea straight pull to remove the handle from the clip;this will require 10 to 20 pounds of force. If notwithin limits, use pliers to adjust the clip.

SERVICE LIFE CHECKS

Testing the ripcord opens the container. If theassembly includes explosive devices, they must bedeactivated at this time. The canopy is then placedon the table with the nameplate up. If theparachute is being placed in service, the date isstenciled on the parachute canopy on thenameplate gore directly below the nameplate.

For a periodic inspection, you should verifythe nameplate data against the Parachute

Configuration, Inspection, and History Record,or “History Card.” If the service life dates listedon the history card are in accordance with theMaintenance Requirement Cards, NAVAIR13-600-4-6-3, check their expiration dates againstthe current date of inspection. Items that havereached service life limits must be replaced. Itemsthat will become overage after the assembly isrepacked may remain in service until the nextinspection date of the complete assembly. Anexception to this are the explosive devices, whichmust be replaced if their expiration date will bereached before the next inspection.

REPLACEMENT OF PARACHUTEASSEMBLIES AND SUBASSEMBLIES

Not all the components of a parachuteassembly come to the end of their service lives atthe same time. After a parachute has been inservice for some time, some of the componentsor subassemblies will have to be replaced in thecourse of the periodic inspections.

If you find an assembly or subassembly thathas reached the service/total life limit, it shouldbe returned to supply for appropriate dispositionaccording to current supply instructions. Beforeturning an overage assembly in to supply, youshould remove all serviceable ready for issue (RFI)subassemblies. You should carefully inspect allnylon webbing and cloth on items to be salvaged.Dirt, oil and grease greatly weaken thesematerials. All fabric items salvaged must have dateof manufacture and date placed into servicemarkings verified prior to disassembly. Cartridgesused on cartridge-actuated parachutes are to behandled, shipped, stored or disposed of inaccordance with NAVAIR 11-100-1. When an in-service parachute does not have a start of servicedate, the service life from date of manufactureexpires as follows: in 7 years for emergency useparachute assemblies; in 10 years for troop andtraining assemblies.

CONTAMINATION INSPECTION

Contamination of a parachute canopy or anassembly could result in the malfunction of thecomplete assembly. It is very important that yoube able to recognize a harmful stain. All parachuteassemblies must be carefully inspected for thefollowing types of contamination:

1. Acid/alkaline2. Salt water

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3.4.5.6.7.8.9.

PerspirationFreshwaterMildew/fungusFire-fighting agentPetroleum productsBloodstainsMud/dirt/sand/trash

Acid and Alkaline Contamination

If a parachute assembly is suspected of havingacid or alkaline contamination, it must be testedwith a pH test paper. A pH reading of 5.0 to 9.0is in the safe zone. Readings below 5.0 indicateexcess acidity, and readings above 9.0 indicateexcess alkalinity. By following the steps listedbelow, you will be able to conduct a properinspection to determine if a stain is acid oralkaline. You need to have distilled water and apH test paper kit (full range and short range).

CAUTION

MAKE SURE THAT THE TESTINGAREA IS FREE OF CONTAMINANTSTO AVOID FALSE READINGS ORDAMAGE TO THE ASSEMBLY.

To perform an acid and alkaline contaminantinspection properly, you should take the followingsteps:

1. First, dampen the suspected area withdistilled water.

2. Place a piece of full-range test paper (0.0to 14.0 pH) on the dampened area. Compare thecolor of the paper with the chart samples todetermine the approximate pH and which specificshort-range test paper to use.

3. Place the short-range test paper indicatedby step 2 on the dampened area. The color thepaper changes to will indicate the pH factor ofthe affected area. By matching the test strip withthe applicable range color chart supplied with thepH indicator kit, you can determine the strengthof the acid or alkaline present.

NOTE: You must be careful not to let thesuspected contaminated area come intocontact with any other area, as this couldspread the damage.

4. Treat contaminated areas of the para-chute assembly in accordance with NAVAIR13-1-6.2.

Other Contaminations

Those stains caused by contact with acid, oil,and salt water are the most harmful to nylon andshould be removed as quickly as possible toprevent further deterioration of the material.Although sun rays do not stain, they are mostharmful to nylon. Parachutes and componentsmust be kept out of the direct sunlight.

INSPECTING FOR WEAR ANDPHYSICAL DEFECTS

Wear in a parachute is not difficult to detect.Chafing at the comers or on outside surfaces iswhere the most wear occurs. Parts of parachutesand related equipment showing excessive wearshould be replaced or repaired, the work to beaccomplished at the lowest maintenance levelcapable of performing the task.

PILOT PARACHUTE INSPECTION

Inspect the fabric drag surfaces, rib pockets,lift webs, seams, and suspension lines for signsof contamination, cuts, tears, burns, fraying, andloose or missing stitches. Inspect the vane materialfor defects and deterioration. Inspect for seamseparation along the seam area where the vaneattaches to the cone and suspension lines. Yarnseparation is acceptable; however, replace thepilot chute if the vane material contains holes, ripsor tears. Inspect the spring assembly for sufficienttension and bends. Replace ail loose or brokentackings. There is little that you can repair on apilot parachute. If any damage is found, you mustreplace the pilot parachute in accordance withNAVAIR 13-1-6.2.

CANOPY INSPECTION

Inspecting the canopy requires the most time.You must take your time in order to be certainthat you don’t miss any defects. NAVAIR13-600-4-6-3 and NAVAIR 13-1-6.2 spell out thestep-by-step procedures for this inspection. Anydamage must be recorded on a canopy damagechart. (See figure 1-15.) To inspect the canopy forpossible defects or damage, you should take thefollowing steps:

1.so its

2.

Lay the canopy on a clean packing tablenameplate gore is facing down.Place tension on the canopy.

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3. Have your helper raise the suspension line.Use Y-stands at the skirt hem to hold thesuspension lines.

4. You, as the packer, start at the skirt hemand inspect the upper radial seam from skirt hemto peak. You inspect the vent hem, collar and ring,lower radial seam, fabric surface, diagonal seamsor tapes, and skirt hem. Minor defects that donot weaken the assembly are not reported on acanopy damage chart. If necessary, minor defectsmay be corrected by light brushing or trimming.

5. Significant damage and major defects, suchas holes, rips, tears, or contaminated areas thathave to be removed, are reported on the canopydamage chart.

Use the same procedures to inspect all canopygores.

SUSPENSION AND VENTLINE INSPECTION

To inspect the suspension lines, you and yourhelper grasp one group of suspension lines at theconnector links and walk toward the canopy skirthem, allowing the lines to run freely over the palmof your hand. Visually examine the lines fordamage and defects. Upon reaching the skirt hem,grasp the remaining groups of lines and inspectthem the same way, walking toward the connectorlinks. The lines at the canopy vent are also visuallyexamined. Your inspection includes, but is notlimited to, the following:

1. General condition of the suspension linesincluding fraying, ruptures, inner cores protrudingfrom lines; dirty, lumpy, hard or thin spots;friction bums; improper overlap length; presence

Figure 1-16.—Suspension line construction.

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Figure 1-17.—Suspension line damage.

of twists in individual lines; and the propersequence of lines on the connector links. To helpyou decide on the various types of damage, seethe examples in figures 1-16 and 1-17.

2. Be sure that each of the suspension linesis in proper rotation at the connector links andthrough the canopy.

3. On an original issue inspection, you mustmeasure the suspension lines for proper length.Apply a 20-pound tension to each line. The lengthof the shortest line and the length of the longestline must not vary more than 2 inches.

4. Inspect the attachment at the skirt hem forthin spots at the V-tabs; also, check the conditionof the V-tabs.

5. Inspect the four line release system. Thefour line release system permits four of thesuspension lines on one side of the parachute tobe detached from the connector links during a

parachute descent. This permits the parachutistto dampen oscillations and to have some controlover the direction the parachute travels whendescending.

6. Other defects should be noted on theParachute Configuration, Inspection and HistoryCard. If a defective line is found that would affectthe safe operation of the assembly, the line mustbe replaced at a depot-level maintenance activity.

CONNECTOR LINK INSPECTION

To inspect connector links, you shouldproceed as follows:

1. First, examine the connector links forproper part numbers, signs of corrosion, dis-tortion, bends, dents, nicks, burrs, sharp edges,breaks, and if applicable, defective yoke and plateassemblies.

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2. If required, examine the yoke and plateassembly for proper installation (fig. 1-18). Whenthe yoke and plate assembly screw is tightened,there should be a maximum of 1/64-inch play inthe assembly. (To tighten the screw use a torqueof 20 to 25 lb-in.)

At this point, a mandatory inspection isperformed by a quality assurance inspector. Allof your work stops until the mandatory inspectionis performed and the assembly has been foundacceptable.

BALLISTIC SPREADING GUNINSPECTION

While inspecting the ballistic spreading gun,you may have to remove, replace, or make someadjustment. All work must be in accordance withthe procedures in the applicable chapter of theNAVAIR 13-1-6.2. The ballistic spreading gun isdescribed in the next chapter of this text.

HARNESS/RISER ASSEMBLYINSPECTION

Inspect the harness webbing for signs ofcontamination from oil, grease, acid, or other

Figure 1-18.—Locked and unlocked connector links.

foreign matter, such as rust at points of contactwith metal parts. Inspect for cuts, twists, fading,excessive wear or fusing (indicated by unusualhardening or softening of webbing fibers), fray-ing, burns, abrasions and loose or broken stitching(in excess of three stitches). If applicable, inspectthe four-line-release lanyard flute for wear andproper attachment. If you find any damage to theharness, dispose of it and replace it in accordancewith applicable rigging and packing procedures.

When a replacement harness is installed, youshould stencil the date, preceded by the letter R,in the center of the horizontal back strap in letters1/2-inch high. For example, R-2-88 indicates areplacement was made in February 1988.

If fewer than three stitches are loose orbroken, repair the riser or harness assembly byusing nylon 6-cord, lock-stitch over original stitchand 3/4 inches on both sides of the original. Usefour to six stitches per inch.

Hardware Inspection

To inspect harness and riser hardware,proceed as follows:

1. Inspect the canopy quick-release fittings forbreaks, corrosion, pitting, bends, dents, and sharp

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edges. Check the tamper-dot on the locking screw.If it is broken, tighten it and apply a new tamper-dot to the screwhead using lacquer (TT-L-32,11136, insignia red) or equivalent. Remove sandor any dirt from the mechanism using an air hoseto blow it out at not more than 50 psi pressure.Wipe dirt and grease from fittings with a cleanrag. Do not lubricate the fittings. Replace alldamaged fittings.

2. With the canopy quick-release fittinglocking cover plate held in the open position,insert a torquemeter into the hexagonal cavitylocated on either end of the knurled locking-levershaft. With the canopy quick-release fittinglocking cover plate held in the open position,rotate the knurled lever shaft until it reaches thestop. Record the torque reading. The allowabletorque is 28 to 50 ounce-inches. All canopy quick-release fittings that do not meet torque testrequirements must be replaced.

3. Inspect all other hardware for signs ofcorrosion, pitting, ease of operation, security ofattachment, bends, dents, nicks, burrs and sharpedges. Make sure that the rollers in the roller yokesturn freely. If you find any parts damaged,forward the riser or harness assembly to supplyfor screening.

NOTE: Hardware that has been rejectedis forwarded to the Commanding Officer,Naval Weapons Center, China Lake.California, Attention: Code END, 4.

Cross-Connector Strap Inspection

Inspect the cross-connector strap(s) for signsof contamination, cuts, fraying, burns, and looseor broken stitching. If you find any damage,dispose of them locally, and replace them inaccordance with applicable rigging and packingprocedures.

RIPCORD ASSEMBLY INSPECTION

The ripcord was inspected before the para-chute was unpacked. Now it is inspected again.To inspect the ripcord assembly, examine thefollowing:

1. Inspect the ripcord handle. Examine thecable and locking pins for signs of corrosion,

bends, dents, cracks, loose swage joints, andbreaks. If damaged, dispose of it locally.

2. Inspect the ripcord housing for signs ofcorrosion, bends, dents, and for security ofattachment. If any damage is found, replace thehousing.

3. Inspect the ripcord housing release clampand baseplate for signs of corrosion, bends, dents,cracks and security of attachment.

4. Inspect the ripcord housing release lanyardand guide for signs of contamination, tears,fraying, loose or broken stitches, cuts, burns,correct length and security of attachment.

5. If you find any loose or damaged tackings,they must be replaced.

Ripcord Handle Pocket Inspection

Inspect the ripcord handle pocket for signs ofcontamination, cuts, tears, burns, fraying, andloose or broken stitches. If such damage is found,the pocket is replaced. You have an option on howthe new pocket can be installed. You may installa new pocket by machine stitching, using nylonthread, size E (V-T-295), or by whip stitching,using waxed nylon 6-cord, type I, doubled,stitches being 3/8-inch apart.

Ripcord Handle Clip Inspection

To inspect the ripcord handle clip, you shoulddo the following:

1. Examine the clip for corrosion, sharpedges, bends, twists, and dents. Examine thewebbing for contamination, fraying, loose orbroken stitching, cuts and burns. Replace anydamaged stitching. If other damage exists, replacewebbing and/or clip.

2. If any maintenance is performed on theclip, repeat the pull-force test outlined inNAVAIR 13-600-4-6-3 and described earlier inthis chapter.

CONTAINER ASSEMBLY INSPECTION

When you inspect the container assembly,examine all flaps, locking cones, and grommets,spring opening bands, and tackings; checking

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fabric, seams, reinforcement, and hardware.Check fabric, seams, webbing and reinforcementfor holes, cuts, tears, fraying, contamination, anddeterioration. Examine hardware for corrosion,bends, dents, nicks, sharp edges, proper function,and security of attachment. Make sure that youkeep a record of any damage for later repairs.Repair holes, tears, snags, or rips in containerfabric using approved procedures as described inNAVAIR 13-1-6.2.

Some parachute containers use rubber retain-ing bands to secure the suspension lines. On mostassemblies these rubber bands must be replacedat each repack regardless of their condition.

COMPLIANCE WITH CURRENTDIRECTIVES

On parachute repack cycles, or whenotherwise directed, inspect the parachuteassembly and components for updating ac-cording to the latest modifications. For eachtype of parachute, refer to the EmergencyPersonnel and Drogue Parachute SystemsManual, NAVAIR 13-1-6.2, and recent Air-crew System bulletins and changes for allcurrent parachute configurations. Do not permitany local modifications without prior approvalby proper authority.

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CHAPTER 2

AUTOMATIC OPENING DEVICES

Learning Objective: Upon completion of this chapter, you will be able torecognize, inspect, and maintain cartridges and cartridge-actuated devices usedwith personnel emergency parachute assemblies.

As you look around the parachute loft, youwill see that it is a very clean, neat, and safe-looking place to work. Although it has thisappearance, there are a few places that are verydangerous. One of the more hazardous places isthe packing table. The packing table may look assafe to you as sitting at home in your easy chairwatching television. However, on the packingtable you will find automatic opening devices.There are two basic opening devices used in theoperation of personnel parachutes.

The first is the automatic parachute ripcordrelease. Working with this actuator is the sameas working with a loaded .38 caliber pistol. Thesecond is the ballistic spreader gun. This gun hasa cartridge; and when fried, it gives the same effectas an exploding hand grenade. Working with anyopening device requires extreme caution—allsafety precautions must be taken to ensure yoursafety as well as that of your coworkers. Thischapter will help you understand the operation,function, and maintenance of this equipment.

AUTOMATIC PARACHUTEACTUATORS

The Navy currently uses the Model 7000automatic parachute ripcord release (fig. 2-1) inits personnel parachute assemblies. It is abarometrically controlled, pyrotechnic device. Theactuator is designed to open a parachute at apreset altitude. The Model 7000 automaticparachute ripcord release is available with twodifferent altitude settings. One is the 10,000-footsetting, plus or minus 1,000 feet (identified bygreen labels on the cover assembly). The aneroidis identified by a green potting seal and a white

Figure 2-1.—Model 7000 Automatic Parachute RipcordRelease.

label with green lettering. The other is the14,000-foot setting, plus or minus 1,000 feet(identified by red labels on the cover assembly).The aneroid is identified by a red potting seal anda white label with red lettering.

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FUNCTION PREPARATION FOR USE

It is impossible for an aircrewman to select thealtitude at which an emergency may occur. Byusing the automatic ripcord release, you can bringthe aircrewman down to a safe altitude before theparachute opens.

When an aircrewman makes an emergencyejection at an altitude above that for which theripcord release is set to open the parachute, thefollowing functions take place:

1. The arming pin is pulled. This pin locks theripcord release firing mechanism while installed.When the arming pin is withdrawn, the assemblyfires at or below the preset altitude of the ripcordrelease.

2. The sear and the aneroid mechanism lockthe ripcord release.

3. As the aircrewman free-falls, increasing airpressure causes the aneroid to contract.

4. As the operating altitude is reached, theaneroid contracts enough to remove the sear fromthe firing hammer lock.

5. The hammer’s firing pin strikes the car-tridge.

6. The time-delay cartridge fires (time de-pending on the type of cartridge used) after thehammer strikes.

7. The piston is forced forward in the barrel,pulling the power cable, which is attached to theparachute locking pins. (The power cable travels3.75 inches.)

8. The locking pins are pulled, and the normalparachute opening sequence begins.

When an aircrewman bails out below theoperating altitude of the automatic parachuteripcord release, the hammer releases as soon asthe arming pin is pulled, and the followingfunctions take place:

1. The hammer’s firing pin strikes the car-tridge.

2. The time-delay cartridge fires (time de-pending on the type of cartridge used) after thehammer strikes.

3. The piston is forced forward in the barrel,pulling the power cable, which is attached to theparachute locking pins.

4. The locking pins are pulled, and the normalparachute opening sequence begins.

When you receive an automatic parachuteripcord release from supply, there are somepreparations for you to make before placing itinto service. Upon removal of the ripcord releasefrom the shipping carton, the exterior parts of theunit must be inspected for damage during shippingand storage. An inspection should be made forcorrosion, dirt, dents, and cracks. If any damageor discrepancy is found, a quality deficiencyreport must be submitted, and a tag must beaffixed to the ripcord release stating that it is notto be used. Remove this tag only after correctionhas been made. Fired ripcord release assembliesmust not be reused.

All Model 7000 automatic parachute ripcordrelease assemblies that fail any inspection pointsmust have a tag affixed stating the nature of thedefects.

NOTE: Refer to NAVAIR 11-100-1.1 forthe cartridge service life/total life. Thecartridge service life must not expire priorto the next scheduled repack of theparachute assembly.

WARNING

YOU SHOULD EXERCISE EXTREMECAUTION WHEN HANDLING AUTO-MATIC RIPCORD RELEASE AS-SEMBLIES AFTER THE CARTRIDGEHAS BEEN INSERTED IN THE BAR-REL. DO NOT ALLOW EITHER ENDOF THE COVER ASSEMBLY TO BEPOINTED TOWARD YOUR FACEAS HIGH VELOCITY FLAME ANDSMOKE MAY BE PRODUCED IF THECARTRIDGE GOES OFF. ANOTHERREASON FOR EXTREME CAUTION ISTHE POSSIBILITY THAT THE PIS-TON OF THE RIPCORD RELEASEMAY BECOME A PROJECTILE IFTHE CARTRIDGE ACCIDENTALLYFIRES.

An automatic ripcord release in service mustbe inspected each time its parachute assembly isrepacked. You must pay particular attention todetail when working on a automatic ripcordrelease. The importance of careful work must beimpressed upon personnel actually performing thework, as well as those assigned to collateral duty

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inspections. You will find more detailedinformation concerning automatic parachuteripcord release assemblies in the EmergencyPersonnel and Drogue Parachute SystemsManual, NAVAIR 13-1-6.2, and the MaintenanceRequirements Cards, NAVAIR 13-600-4-6-3.

MAINTENANCE

Maintenance on any automatic ripcord releasein service must be performed each time itsparachute assembly is repacked. Maintenanceconsists of the following:

. Disarming

. Inspection

. Firing altitude check

. Arming and assembly

. Checkout of armed mechanism

As you work on a automatic ripcordrelease assembly, you are required to per-form several different types of maintenanceand inspections. You are required to in-spect the operational condition of the auto-matic ripcord release before installing it ina parachute assembly. If you find any damageor an inspection discrepancy, submit a qualitydeficiency report, as discussed in OPNAVINST4790.2 (series).

NOTE: Under no circumstances shouldan unsatisfactory ripcord release be in-stalled.

The first step in performing the normalinspection and maintenance on a automaticripcord release is to disarm it. Then you are readyto inspect and perform the firing altitude checks.

DISARMING

Anytime you are required to disarm a ripcordrelease assembly, follow the procedures outlinedin NAVAIR-13-1-6.2. The discussion that followsclosely parallels those procedures. A partsbreakdown can be seen in figure 2-1.

NOTE: To remove the arming cablehousing from the ripcord release, de-press the safety retainer release (fig. 2-1).NEVER try to remove the arming cablefrom an armed ripcord release assembly bypulling on the cable. This fires the auto-matic ripcord release.

1. Open the ripcord release pocket, andremove the ripcord release only a sufficientdistance to allow disassembly.

2. Remove the locking screw and washer.

NOTE: The cover and power cablehousing assembly and the receiver andbarrel assembly are serialized matched sets.Do not mix these assemblies.

3. Slide the cover off the receiver and barrelassembly.

4. Disengage the barrel snap lock. A close-upof this operation is shown in figure 2-2.

5. Remove the cartridge from the barrel as-sembly (fig. 2-1). Do not proceed until the qualityassurance inspector (QA) has verified this step.

6. Remove the ripcord release assembly andthe arming cable housing from the parachutecontainer.

Figure 2-2.—Disengaging barrel snap lock.

2-3

Figure 2-3.—Checking firing pin and hammer.

INSPECTION

To inspect the automatic ripcord release,proceed as follows:

1. Inspect the cover and power cable housingassembly for nicks, gouges, distortion, corrosion,and security of the power cable housing.

2. Inspect the power cable for freedom ofmovement, and secure attachment of the swagedball and power cable eye.

3. Inspect the receiver and barrel assembly forexcessive nicks, cracks, gouges, distortion, andcorrosion or other damage that could cause amalfunction while in service.

4. Inspect the firing pin on the hammer forflattening, gouges, or other damage (fig. 2-3).

5. You must secure the arming pin byinserting the pin in the retainer while the barrelis unlocked. Press the pin firmly into place untilit locks into the pin groove. The pin should nowbe held securely. Do not twist the socket as thiswill break the shear pin.

NOTE: Early Model 7000 automaticparachute ripcord release assemblies usesafety wire, as shown in figure 2-1. Wheninspecting these assemblies, check forsecurity and the proper type of wire.

6. Inspect the socket for visible damage andretention of the socket and piston by a shear pin(figs. 2-1 and 2-4).

7. Inspect the snap lock pins for security andabsence of damage (figs. 2-1 and 2-5).

NOTE: If the tamper dot is broken,you need to torque the screw to a value of14 1/2 to 15 1/2 inch-pounds and apply anew tamper dot.

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Figure 2-4.-Checking for proper retention of socket by ashear pin.

Figure 2-5.—Checking for security of snap lock.

Figure 2-6.-Checking springs and tamper dot.

8. Inspect the leaf springs on the receiver andbarrel assembly for damage. Make sure theretaining screw has not loosened. (Check thetamper dot on the screw and spring, as shown infigure 2-6.)

Figure 2-7.—Inspecting aneroid seal.

Figure 2-8.-Inspecting gasket seal.

9. Check the sealing compound on the aner-oid screw, shown in figure 2-7. The seal must beintact and undisturbed. Cracks due to normalaging of seal material are acceptable.

10. Inspect the Teflon seal. Be sure that thecup side of the seal is facing the piston (fig. 2-8).

FIRING ALTITUDE CHECK

To check for the proper firing altitude of theautomatic ripcord release, you must first befamiliar with the automatic parachute ripcordrelease test set.

AUTOMATIC PARACHUTE RIPCORDRELEASE TEST SET

The automatic parachute ripcord release testset, shown in figure 2-9, is designed to test thesensitivity of the automatic ripcord release to apreset pressure altitude through use of an aneroidblocking mechanism.

The principal action that you test is theconsistency of the aneroid in actuating the releasemechanism at a predetermined altitude. To do

Figure 2-9.—Automatic parachute ripcord release test set.

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this, you first evacuate air from a test chamberto simulate an increase in altitude. When you haveachieved a simulated altitude above the presetaltitude of the ripcord release, you extract thearming pin, which arms the parachute ripcordrelease firing mechanism. Then you bleed outsideair back into the test chamber at a controlled rateto simulate a specific rate of descent. When thepressure reaches the value for which the automaticripcord release has been set, the aneroid willunlock the sear if the pressure sensitivity is withintolerance.

The test chamber, its evacuation system,instrumentation, and controls are packagedin one container. The test chamber is de-signed to withstand a vacuum equivalentto an altitude of 30,000 feet. The chamberholds the entire 7000 series automatic para-chute ripcord release, and it includes thenecessary brackets to support and positionthe ripcord release within the chamber dur-ing the test cycle. An access door/observationwindow is also provided.

NOTE: Before testing an automaticparachute ripcord release, the test chamberaltimeter should read 29.92 inches ofmercury barometric pressure.

RIPCORD RELEASE TESTPROCEDURE

Plug the test unit’s power cord into a115-volt, 60 Hz, ac power source. Placethe power switch in the ON position, openthe test chamber door, and insert the arm-ing pin cable into the side of the ripcordrelease with the aneroid end toward theoperator.

To test the ripcord release, follow theseprocedures:

1. Ensure the test chamber has been cali-brated. Install the test chamber substitute armingpin into the ripcord release. If the barometricpressure reading of the altimeter isn’t 29.92, youwill not get a true reading of the firing altitudes.Therefore, you must adjust the altimeter to theproper setting when required.

2. Install a dummy cartridge.

Figure 2-10.—Locking barrel assembly.

CAUTION

DO NOT RELEASE THE RIPCORDRELEASE FIRING MECHANISMWITHOUT A DUMMY CARTRIDGEINSTALLED, AS THIS COULD DIS-TORT THE FIREWALL. THIS DIS-TORTION COULD CAUSE A LATERMALFUNCTION.

3. Press the barrel down into position in thereceiver. As the barrel reaches the proper position,exert forward pressure on the snap. lock, causingthe snap lock pins to lock the barrel in position(fig. 2-10).

4. Install the barrel and receiver into the testchamber. Check your altimeter (fig. 2-9) for asetting of 29.92.

5. Evacuate the chamber to an altitude of25,000 feet. This is done by using the climb toggleswitch.

6. Decrease the altitude by using the descendtoggle. The chamber simulates descent at a rateof 175 to 200 feet per second.

7. At approximately 20,000 feet actuate thearm toggle switch to withdraw the arming pinfrom the barrel and receiver.

8. At the firing altitude the ripcord releaseshould fire. (You have a tolerance of plus orminus 1,000 feet at this time.)

9. Record the altitude at which the ripcordrelease assembly’s firing pin strikes the dummycartridge. The firing altitude is recorded on theparachute configuration, inspection, and historyrecord. The quality assurance inspector will checkthis point of the procedure.

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WARNING

AFTER TEST FIRING, YOU MUSTNOT USE A METAL TOOL TO PUSHTHE HAMMER AND LOCK AS-SEMBLY BACK FROM THE FIRINGWALL. TAKE EXTREME CARE TOAVOID SCRATCHING OR ABRADINGTHE POLISHED SURFACE OF THELOCK. THE PURPOSE OF THE LOCKASSEMBLY IS TO MATE WITH THEANEROID SEAR AND INITIATE FIR-ING AT A PRESCRIBED ALTITUDE.A ROUGH OR SCRATCHED LOCK-ING ASSEMBLY MAY CAUSE AHANGUP DURING THE UNLOCKINGFUNCTION.

NOTE: Ripcord releaseassemblies with part number711-07022-30 (10,000-foot)must fire at 10,000 feet (plusor minus 1,000 feet) pressurealtitude. Ripcord release as-semblies with part number711-07022-34 (14,000-foot)must fire at 14,000 feet(plus or minus 1,000 feet)pressure altitude.

10. Three firing altitude checks must be made.Any ripcord release that does not meet testrequirements on all three checks will be rejected.Adjustments are not to be made.

11. Remove the dummy cartridge and inspectit for an indentation caused by the hammer firingpin striking the cartridge. This dent must be visibleto the QA performing the inspection.

ARMING AND ASSEMBLING THEAUTOMATIC PARACHUTE RIPCORDRELEASE

The following instructions are the same typeyou will follow in the shop when arming andassembling the Model 7000 ripcord release. Whenyou use the NAVAIR 13-1-6.2 manual and cometo a step that is followed by “(QA),” that stepmust be inspected by a QA.

1. To arm the ripcord release that is installedin a parachute, your first step is to insert thearming cable housing through the holes in theparachute container and ripcord release pocket.

2. Next, feed the arming cable through thearming cable housing. Depending on application,the arming cable may be inserted at either side ofreceiver and barrel assembly (fig. 2-11).

Figure 2-11.—Installing an arming cable.

Figure 2-12.-Installing an arming cable housing.

3. With the ripcord release barrel in the openposition, install the arming pin into the ripcordrelease. The pin must pass through the hole in theside of the receiver, through the firing mechanismlock, and out the opposite side of the receiver.

4. Next, you connect the arming cable housingto the receiver and barrel assembly. Ensure thesafety retainer secures the housing to the receiver(fig. 2-12). Be sure that you check the cartridgeservice life at this time. You should not install acartridge that will expire prior to the next scheduledrepack of the assembly. Refer to NAVAIR11-100-1 for the service/total life of cartridges.

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5. You should enter the cartridge time delay,part number, type, expiration date, lot number,can open/installation date, the CAD DODIC (De-partment of Defense Identification Code), and thedate of manufacture or overhaul on the parachuteConfiguration, Inspection, and History Record.

6. Insert a proper time-delay cartridge in thebarrel. Refer to the applicable parachute chapterto determine which time-delay cartridge shouldbe used. While you are pressing down on thebarrel, look through the inspection hole in thereceiver and ensure that the hammer assemblydoes not swing towards the firewall. If thehammer swings, the arming pin is improperlyinstalled. Do not attempt to assemble the ripcordrelease any further, as this could fire the cartridge.

7. Press the barrel down into position in thereceiver (fig. 2-10). As the barrel reaches properposition, exert forward pressure on the snap lock.This causes the snap lock pins to lock the barrelin position. Ensure that the snap lock is alignedwith the alignment arrow.

8. Hold the ripcord release, as shown in figure2-13, and slide the receiver and barrel assemblyinto the cover and power cable assembly until theholes for the screw are aligned.

9. Install the locking screw and lock washer.Apply a tamper dot to the locking screw, usingred lacquer.

CHECKOUT OF ARMED RIPCORDRELEASE

To check out an armed automatic ripcordrelease, you should proceed as follows:

1. Check the arming cable for properinstallation, as shown in figure 2-14. The armingpin must be visible (extending through the sideof the receiver).

Figure 2-13.—Sliding receiver and barrel into cover assembly.

Figure 2-14.—Checking arming pin for proper installation.

Figure 2-15.—Checking roll pin.

2-15).

Figure 2-16.—Checking lock screw.

2. Check for correct position of thespring and centering of roll pin in hole (fig.

3. Check to make sure the locking screw isinstalled. Be sure that the tamper dot isn’t broken(fig. 2-16).

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4. Check for proper position of the aneroid To install an automatic parachute ripcord(fig. 2-17). release, you must refer to the Emergency

Personnel and Drogue Parachute Systems5. The cartridge must be installed (fig. 2-18). Manual, NAVAIR 13-1-6.2.

Look through the port and verify that thecartridge is installed.

6. Complete the ripcord release installation in

BALLISTIC SPREADINGGUN ASSEMBLY

accordance with the applicable parachute chapter The ballistic spreading gun isin NAVAIR 13-1-6.2. actuated device that ensures rapid

Figure 2-17.—Checking for proper position of aneroid.

a mechanicallyinflation of the

Figure 2-18.—Checking for cartridge.

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Figure 2-19.—Spreading gun assembly.

main parachute canopy, and it reduces randominflation time of the canopy during high-speedejections (figs. 2-19 and 2-20).

DESCRIPTION

The spreader gun assembly consists of aspreader housing, 14 pistons, slugs, and retainers,an impulse cartridge, a fail-safe mechanism, anda hardware retention lanyard.

The spreader gun is provided with a fail-safeassembly in the event of a cartridge malfunction.The fail-safe assembly consists of a nylon sleeveclipped to the sheer band assembly.

A safety pin is inserted in the firing mechanismduring handling to prevent accidental firing. Thecartridge for the spreader gun is threaded into thebreech of the housing and has a retention cordattached. The spreader gun is positioned at thehem of the main parachute between the retainingcord and lower firing lanyards.

The retaining cord is looped around the ventlines and the pilot parachute connector cord.

Figure 2-20.—Spreading gun assembly parts breakdown.

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The lower firing lanyard is attached to theconnector link next to the suspension lines. Twosuspension lines and a loop from the parachutehem are attached to each slug. A cover plate holdsthe two lines and loop in the channels of each slug.

OPERATION

When actuated, the parachute canopy deploysby either an internal pilot chute or by the externalpilot chute. Just prior to full canopy andsuspension line deployment, the firing lanyardpulls the firing pin from the firing mechanism.This releases the striker, which strikes the cartridgeprimer. As the cartridge fires, the 14 slugs arepropelled outward. They simultaneously drag theattached suspension lines outward in a 360-degreespread. This firing sequence occurs prior to anytension being placed on the suspension lines.Spreading is stopped when tension starts to buildup in the suspension lines; so, at high speed itproduces a 4-foot diameter mouth, and at lowspeed, it produces an 8-foot diameter mouth.

In the event of a cartridge malfunction, a“fail-safe” backup subsystem operates. After thefiring pin is withdrawn, the firing lanyard exerts25 to 38 pounds of tension on the fail-safeassembly sleeve, which retracts the shear bandassembly. This releases the slugs and allows thecanopy to inflate aerodynamically.

IDENTIFICATION AND HANDLING

An identification tag is attached to thespreader gun and contains the following data:nomenclature, manufacturer’s part number,revision status, serial number, date of manu-facture, and name and address of themanufacturer.

A warning label is sewn on each side of thesleeve protecting the firing lanyard and to theouter pack assembly. This label reads as follows:

WARNING

THIS PARACHUTE CONTAINS ACARTRIDGE ACTUATED DEVICE.FOR HANDLING INSTRUCTIONS SEEPARACHUTE PACKING MANUAL.

There is a tag attached to the safety pin thatreads: “REMOVE PIN BEFORE PACKING.”Assemblies shipped without a cartridge must havea shipping plug installed.

Service Life

Refer to NAVAIR 11-100-1-1 for the shelf/installed life of the spreading gun cartridge. Theservice life expiration date (month and year) ismarked with indelible ink on the side of eachcartridge.

NOTE: If the date the sealed con-tainer was opened is not available, theINSTALLED LIFE is computed from thedate of manufacture as determined fromthe lot number.

Log Entries

You should enter on the Parachute Historyand Record Card the date of primary installationof the spreader gun to the parachute canopy, thelot number, expiration date, part number, CADDODIC, and date of manufacture or overhaul ofthe cartridge.

Safety Precautions

Treat the spreaderstrument. The spreaderas class C ammunition

gun as a delicate in-gun cartridge is treatedin accordance with the

general safety precautions given in the cartridgemanual (NAVAIR 11-100-1.1).

WARNING

YOU MUST ALWAYS REMEMBERTHAT THE BALLISTIC SPREADINGGUN IS LETHAL WHEN ACTIVATEDWITHOUT A CANOPY ATTACHED.DO NOT REMOVE THE SAFETY PINUNTIL THE PROPER TIME ASPRESCRIBED IN THE PACKINGMANUAL.

DO NOT REMOVE LANYARD RE-TAINING PIN WHEN REPLACINGUPPER RETAINING CORD.

NOTE: Be sure that the cartridgeservice life will not expire prior tothe next service check. Be sure thecartridge expiration date is enteredin the Parachute History and Re-cord Card.

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REMOVAL OF BALLISTICSPREADING GUN

Before you work on a spreader gun, alwaysensure that a safety pin is installed. If you haveto remove a damaged or defective spreading gun,proceed as follows:

1. Loosen the screws holding the plates to thespreading gun slugs to allow suspension lines tobe removed.

2. Slip all the suspension lines and attachedloops from under the plates.

3. Disconnect the retaining cord from the ventlines.

4. Tie one end of a temporary 20-foot line tothe vent lines, and tie its other end to the free endof the retaining cord.

5. Pull the retaining cord out of the canopyfrom the skirt end.

6. Untie the temporary 20-foot line from theretaining cord, and remove the damaged ordefective gun from the table.

7. To install a new or repaired spreading gun,follow the procedures outlined in the applicableparachute assembly chapter in the EmergencyPersonnel and Drogue Parachute SystemsManual, NAVAIR 13-1-6.2.

BALLISTIC SPREADING GUNCARTRIDGE REPLACEMENT ANDPULL-FORCE CHECK

WARNING

BEFORE YOU ATTEMPT TO RE-PLACE A CARTRIDGE, YOU MUSTREMEMBER THE SPREADING GUNEMPLOYS AN EXPLOSIVE CAR-TRIDGE. FAILURE TO OBSERVEPROPER PROCEDURES COULD RE-SULT IN SERIOUS INJURY ORDEATH.

NOTE: You must use onlythe special tools furnished forcartridge removal or replace-ment. It is recommended thata helper assist you in perform-ing the cartridge replacementby verifying procedures as eachstep is accomplished. You mustperform a firing pin pull-forcecheck each time you replace acartridge.

Figure 2-21.—Spreading gun test fixture.

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By following the steps outlined below, you canreplace the cartridge and perform the firing pinpull-force test in a safe manner.

1. Clamp the spreading gun test fixtureto the packing table. Use one C-clamp positionedas close as possible to the clamp assembly. Seefigure 2-21 for the test fixture parts identifi-cation.

2. You must remove the cartridge extractorwrench from the swivel bolt attached to thespreading gun clamp assembly.

3. Then place the cartridge end of thespreading gun into a spreading gun clampassembly (fig. 2-22). Ensure that the lip on theclamp assembly circles the spreading gun housing.Route the retaining cord through the vertical slotin the center of the clamp and spread suspensionlines to prevent entrapment between gun andclamp. Position the swivel bolt in the horizontalslot in the clamp, and torque the swivel bolt nutto 7 ± 1/2 foot-pounds.

4. Place the pins of the cartridge extractorwrench into holes in the cartridge. Loosen thecartridge using pressure against a 3/4-inch socket,as shown in figure 2-23.

NOTE: If you have difficulty in re-moving the cartridge by using the ex-tractor wrench furnished with the testfixture, use a special cartridge extractortool. Cut and remove the retaining cordat the base of the cartridge. Place the slotof the special tool over the retaining cordpin, and loosen the cartridge by using a1/2-inch socket.

5. Remove the spreading gun from theclamp or V-block assembly. Manually un-screw and remove the cartridge from thechamber.

6. Remove the cartridge from the retainingcord by removing the pin. Retain the pin forreinstallation if required. The old cartridge mustbe disposed of in accordance with currentdirectives.

7. Remove the safety pin from the spreadinggun.

8. Spread the canopy skirt hem and suspen-sion lines to expose the cartridge chamber.Slide the spreading gun onto the test fixture shaft

Figure 2-22.—Placing spreader gun in gun clamp.

Figure 2-23.-Loosening cartridge.

2-13

Figure 22-24.—Sliding on to test fixture.

so that the shaft butts against the bottom of thecartridge chamber (fig. 2-24).

9. Open the four snap fasteners on thespreading gun extractor sleeve to expose the firingpin housing. Slide the block assembly at the centerof the test fixture under the firing pin housinguntil the block assembly pin slides into thebaseplate hole. Align the firing pin so that the holein the firing pin is horizontal. The firing lanyardis located at the top. (See figure 2-25.)

Figure 2-25.—Spreading gun installation.

10. Attach the hook assembly to the firing pinhole, and slide the hook assembly block over thenut that is attached to the pull gage. (See figure2-21).

11. Move the switch on the pull gage to thecenter position. You must zero your meter needleby rotating the bezel on the dial. Move the switchto the full down position, away from the meter,for recording the pull force.

12. The QA verifies the test fixture lever firingpin releases. The pull force must go between 25and 38 pounds. If a gun has failed the first test,it must be retested two more times. The gun mustpass both retests. Record the force required torelease the firing pin on the ParachuteConfiguration, Inspection, and History Record.When a gun fails, it is removed and returned tosupply as a defective item.

13. After the pull-force measurement has beenobtained, remove the hook assembly from thefiring gun.

14. Push the firing pin back into the housing.Push the control disc firmly inward, forcing thefiring pin out of the housing. Apply inward handpressure to the firing pin as it moves out. Continueto move the control disc inward, applying handpressure to the firing pin until it clicks into place.When a click is heard, the gun is cocked. Gentlyrelease the control disc while still exerting pressureon the pin.

15. The QA inspector must tug gently on thefiring pin until the effect of spring loading is felt.If the pin moves without spring tension, the gunis not cocked, and step 14 must be repeated.

16. Release the block assembly by pulling thepin out of the hole in the baseplate and slidingthe block away from the spreading gun. Removethe gun from the shaft. Do not remove the gunby pulling on the firing lanyard.

17. At this time, install the safety pin.

CAUTION

WHEN YOU ARE USING ALCOHOLTO CLEAN THE CARTRIDGE CHAM-BER, DO NOT ALLOW ALCOHOL TOFLOW INSIDE THE GUN BECAUSETHIS COULD DAMAGE THE O-RINGSAND LUBRICATION.

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18. Clean the cartridge chamber and threadswith a small amount of denatured alcohol. Ensurethat the old sealing compound and all foreignmatter is removed. Tilt the gun to allow thealcohol to run out of the gun.

19. Feel the inside of the cartridge chamberto ensure that the slug pistons do not stick outinside the chamber. If the pistons do protrude,push them back as necessary. Feel the bottom ofthe chamber to ensure there is no foreign objectin the chamber. The bottom should be smoothmetal.

20. Prior to the cartridge installation, stampon the cartridge, in the approximate positionshown in figure 2-26, the following information:lot number, manufacturer’s symbol, month andyear of loading. Use black marking ink and makethe characters as large as practicable for theavailable space. The same markings, plus ex-piration date and the can open date, must alsobe stamped on the cartridge head, using charactersno smaller than 1/16 inch high.

21. Record the type of cartridge, part number,delay time, lot number, and service life expirationdate on the Parachute Configuration, Inspection,and History Record.

22. Apply sealing compound to the top twothreads of the cartridge. (See figure 2-26.)

Figure 2-26.-Cartridge markings-head and side.

23. Attach the new cartridge to the retainingcord by passing the pin through the screw baseof the cartridge and the loop that is located at theend of the retaining cord.

NOTE: Never force the cartridge into thechamber. This could damage the gun.When a cartridge is properly installed, thebase should be approximately even withthe top edge of the chamber. If thecartridge base is more than one threadabove the edge, remove the cartridge andcheck the bottom of the chamber for anyobstruction, such as protruding slugpistons.

24. Having inserted the cartridge into thechamber, you tighten it manually. If the cartridgestops before the threads are engaged, remove thecartridge and again check for protruding slugpistons. Push them back if necessary.

25. Replace the gun in the clamp or V-blockassembly in accordance with steps 3 and 4. Usinga cartridge extractor wrench and torque wrenchwith a 3/4-inch socket, you must torque thecartridge to 84 inch-pounds (plus or minus 12inch-pounds).

26. Remove the spreading gun from the clampor V-block assembly. Do not remove the safetypin. Put the cartridge extractor wrench back onthe swivel/stanchion bolt.

27. Check stowage of the firing lanyard.Restow it if necessary.

28. Close the extractor sleeve. Now your jobhas been completed.

To install a ballistic spreader gun onto aparachute, you must refer to the EmergencyPersonnel and Drogue Parachute SystemsManual, NAVAIR 13-1-6.2. Repacking aparachute with a ballistic spreader gun is discussedin chapter 3 of this manual.

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CHAPTER 3

NES-12 PERSONNEL PARACHUTE SYSTEM

Learning Objective: Upon completion of this chapter, you will be able tounderstand the theory of operation and perform a speciaL inspection on theNES-12 parachute assembly.

The modern high-performance aircraft usedby the Navy today make extreme demands ofemergency escape devices. The most critical timefor ejection from an aircraft is at low altitudes—especially on takeoffs and landings. The ultimategoal in seat performance (to which engineers havebeen working) is one that safely ejects theoccupant at zero airspeed and at zero altitude, atlow altitudes under a high speed, or under otheradverse altitude conditions. The system discussedin this chapter gives the aircrewman a zeroairspeed and a zero altitude ejection system.

The 1G series ejection seats separate from theaircrewman by means of a rocket that forciblypropels the seat away from the crew member afterejection.

After the aircrew member ejects from theaircraft, a static line on the outside of thecontainer pulls the external pilot chute from itspocket. The sequence of events shown in figure3-1 commences. This static line is also attachedto the arming cable for the automatic parachuteripcord release. The external pilot chute isintended to cause the parachute to open morerapidly, especially at low altitudes or duringground-level ejection. It is of a tristage design andfunctions as follows: At speeds from 0 to 90knots, it will inflate to full diameter; at speedsbetween 90 to 250 knots, the full diameter willreduce to 24 inches; and at speeds in excess of 250knots, it will invert, but its effective drag will besufficient to stabilize the aircrew member duringfree fall and also aid in the extraction of the maincanopy during deployment.

At a preset altitude, the automatic ripcordrelease fires, pulling the ripcord pins from thelocking cones, allowing the spring opening bandsto open the container. The internal pilot parachutesprings from the container and fills with air during

this operation. The external pilot chute releaseassembly frees the shear link cable when thecontainer opens.

The internal pilot parachute causes the maincanopy to be pulled from the container, followedby the suspension lines. A short piece of 18-poundnylon tape is used to momentarily shorten thecanopy’s effective length during low-speedejection, which, in turn, promotes more positiveopening characteristics. Just prior to fullsuspension line stretch, the ballistic spreading unfires, forcing the suspension lines out at the skirthem. This rapidly opens the canopy and allowsit to fill with air faster. Ties on the connector linksbreak as load is applied, allowing the risers to bepulled from the container.

NOTE: If the spreading gun fails to fire,the slugs separate from the gun assemblyat full suspension line stretch, allowing thecanopy to open aerodynamically.

The aircrew member hangs suspended in hisharness from the quick-release shoulder fittingsduring descent. The parachute has the four-linerelease system that was described previously. Bymanually actuating this system, the aircrewmanis able to maneuver the parachute to a lesshazardous landing site and to reduce oscillationduring descent. Upon landing, the canopy andsuspension lines can be disengaged from theintegrated torso suit by means of the quick-releaseshoulder fittings.

NOTE: After the incorporation of AircrewSystem Change 446, the seawater activatedrelease system provides an automaticbackup method of releasing the risers afterthe crew member makes a seawater entry.

3-1

Figure 3-1.—Ejection system sequence of events.

3-2

If the aircrew member should have tomanually separate from the seat and initiate theparachute operation, only the internal pilotparachute will deploy the main canopy. Theexternal pilot chute bridle is disconnected by

means of the external pilot parachute overridedisconnect assembly, which is discussed later inthis chapter.

The NES-12 personnel parachute (fig. 3-2) isa back-type parachute used with an integrated

Figure 3-2.—Personnel Parachute Assembly, NES-12.

3-3

torso harness suit as part of an ejection seat escapesystem.

The NES-12 parachute assemblies include amodified 28-foot diameter, flat nylon canopy with28 gores. A ballistic spreading gun is used torapidly deploy the canopy. The canopy is packedin a semirigid contoured container. Theseassemblies also include the tristage external pilotchute (EPC) and an internal pilot chute. The riserassembly, which includes the shoulder restraintsystem, is rigged to the container and is connectedto the torso harness suit with quick-release fittings.The integrated torso harness suit combines theaircrewman’s parachute harness and lap andshoulder restraint straps. The harness is channeledthrough the torso suit to retain it in position andto aid in donning. When aboard the aircraft andseated, the aircrewman connects the quick-releasefittings on the parachute riser assembly to thequick-release fittings on the parachute integratedtorso suit. The survival kit and the lap restraintsystem are also connected to the integrated torsosuit by means of quick-release fittings.

RIGGING

To obtain the NES-12 parachute, you ordereach component separately. You must rig theparts together to forma complete assembly. Whenyou start to work on this or any parachute, therigging and packing will be done under idealconditions in a parachute loft. When a parachuteassembly must be packed under unfavorableconditions, provisions must be made to protectit from possible damage and excessive humidity.Quality assurance (QA) points are included inrigging and packing procedures. When a step isfollowed by “(QA),” it is a QA requirement. Allwork STOPS until a quality assurance inspectorperforms the requirements listed at the end of theapplicable procedure.

The packing of a parachute assembly mustNOT be interrupted after the packing operationhas been started. If unforeseen circumstancescause the packing operation to be interrupted, theparachute assembly must be completely repacked.

The rigging covered in this chapter applies toan original issue parachute assembly.

NOTE: This rate training manual is not tobe used as a substitute for the NAVAIR13-1-6.2 or the NAVAIR 13-600-4-6-3manuals.

PRELIMINARY PROCEDURES

After you have laid out the parachute andconnected the connector links to the propertension hooks, attach the internal pilot parachute.This is done by routing the small loop of the bridleassembly through the loop in the pilot parachute.Pass the free end (large loop) of the bridleassembly through the small loop, forming a lark’shead knot. Draw it tight. Pass one free end (largeloop) of the bridle assembly around the canopyvent lines at the peak of the canopy. Pass the pilotparachute through the large loop of the bridleassembly, forming a lark’s head knot, and drawtight. Now, attach a tension strap to the canopyvent lines and tighten it.

At this time, you should inspect the completeparachute assembly following the directions inNAVAIR 13-1-6.2 and NAVAIR 13-600-4-6-3.This inspection has been covered in chapter 1 ofthis manual.

INSTALLATION OF SPREADING GUN

A ballistic spreading gun (fig. 3-3) is usedin the parachute. The procedures for inspect-ing this device was discussed in chapter 2.After the parachute has been inspected and

Figure 3-3.—Ballistic spreading gun assembly.

3-4

Figure 3-4.-Routing line for pulling retaining cord throughcanopy.

rigged, install the spreading gun using thefollowing procedures:

WARNING

BEFORE COMMENCING ANY FUR-THER OPERATIONS, ENSURE THATTHE SAFETY-PIN IS INSTALLED INTHE SPREADING GUN.

Tie apiece of Type III nylon suspension line20 feet long to a shot bag (fig. 3-4).

Throw the shot bag attached to the linethrough the canopy gores so that it reaches thecanopy peak. Then pull the shot bag through thevent hem and tie the line temporarily to the ventlines. Secure the bottom end of this line to keepit in place while you whip and fold the canopy.When the canopy has been whipped and folded,tie the free end of this line to the end of thespreading gun retaining cord and pull the retainingcord through the canopy and out the peak.

Untie the Type III nylon line from theretaining cord and vent lines, and route theretaining cord through the lark’s head knot in thepilot parachute connector strap and under all thevent lines. The retaining cord has a plastic sleevethat should be centered over the indexing line onthe retaining cord. Align the indexing line on theretaining cord above the vent lines.

With the help of a bodkin tool, telescope 2inches of the retaining cord into itself to form a

Figure 3-5.—Rigging retaining cord.

3-inch loop (± 1/4 inch) around the vent lines andconnector strap, as shown in figure 3-5. Cut 1 inchoff the end of the retaining cord at a 45-degreeangle.

Tie a half-hitch around the retaining cord andcomplete the splice by telescoping the remainderof the end into the retaining cord, as shown infigure 3-6. Work the line until it becomes smoothon the inside of its casing.

Tack the end inside the retaining cord with twoturns of waxed nylon 6-cord, doubled. Tie theends with a surgeon’s knot followed by a squareknot.

Now position the spreading gun at the skirthem. Place the spreading gun between the suspen-sion line groups 1 through 14 and 15 through 28 sothe retaining cord of the gun faces the canopy.Remove the tension strap from the canopy peak.

Figure 3-6.—Rigging retaining cord (completed splice).

3-3

Figure 3-8.—Installing suspension lines.

Rotate the gun so the slug labeled “14-13” is

Figure 3-7.–Attachment of spreading gun to suspensionlines.

facing up, and loosen the screws and plate on thisslug. You will find two slots on the face of eachslug. One is “closed” or covered when the plateis in place. The other is open to the side of theslug (fig. 3-7). Place suspension line number 13and one side of the loop of line attached to thecanopy hem in the closed slot of the slug (fig. 3-8).Place suspension line 14 in the open slot of thesame slug.

Pass the loop around the plate and over thesuspension line in the slug. Secure the plate to theslug with screws and ensure the suspension linesmove freely in the slots. Torque the plate screwsto 6 (plus or minus 1/2) pound-inches and applyred tamper dot.

Secure the remainder of the suspension linesand loops to corresponding slugs in the samemanner. Work from suspension line 12 through1 and from line 15 through 28 (fig. 3-9).

After the above procedures are completed, youmust have a QA inspect the completed installationof the spreading gun.

THE EXTERNAL PILOT PARACHUTE

A special feature of the NES-12 parachute isthe external pilot parachute. To function properly,

Figure 3-9.—Complete set of suspension lines.

the external parachute is connected to the cordthat links the internal pilot chute to the maincanopy vent lines. A special device is used tojettison the external chute at high speeds. Thisdevice is the override disconnect assembly, shown

3-6

Figure 3-10.–Override disconnect.

in figure 3-10. It consists of two hooks or searsthat are kept in engagement as long as they areinside the barrel.

As long as tension is applied to the externalpilot chute connection, the override will remainlocked. Once the internal pilot chute takes controlof the tension, the override connection will releaseor unlock, allowing the external pilot chute to bereleased.

To attach the external pilot parachute, proceedas follows:

1. Insert the spring and sear (fig. 3-10) intothe wide end of the barrel assembly of the overridedisconnect. The spring and sear will be connectedto the external pilot chute bridle, as shown infigure 3-11. With the aid of a temporary locking

pin, push the sear into the barrel until it isprotruding from the other end.

2. Engage the sear attached to the internalpilot chute connector cord with the sear, whichis protruding from the override disconnect, andrelease the tension by removing the temporarylocking pin. This will cause the two sears to lockwithin the barrel assembly of the overridedisconnect. As you can see in figure 3-11, theexternal and internal pilot chutes are now lockedtogether.

3. Tack the override disconnect to the internalpilot parachute connector strap 3 inches (plus orminus 1/4 inch) above the knot, securing theconnector strap to the vent lines at two places.Use two turns of waxed nylon 6-cord (V-T0295),doubled, for each tacking. Tie the ends with asurgeon’s knot followed by a square knot.

SUSPENSION LINE CONTINUITYCHECK WITH SPREADING GUNINSTALLED

Although you have checked the continuity ofsuspension lines prior to installing the spreadergun, they must be checked again to ensure thatyou haven’t gotten any lines out of sequence orhave crossed a line causing a twist. To checksuspension lines continuity, proceed as follows:

WARNING

ENSURE THE SAFETY PIN IS IN-STALLED IN THE SPREADING GUN(FIG. 3-12).

Figure 3-11.—Tacking override disconnects. Figure 3-12.—Inserting safety pins.

3-7

. If the canopy isn’t already under tension,attach a tension strap hook to the canopy ventlines and tighten.

Figure 3-13.—Arrangement of suspension lines on connectorlinks.

Figure 3-14.—Arrangement of suspension lines on spreadinggun.

Figure 3-15.—Straightening canopy gores.

. The suspension line must be arranged onthe connector links, as shown in figure 3-13, andon the spreader gun, as shown in figure 3-14. Thespreader guns must be turned so that suspensionlines 15 and 14 face up. The suspension lines mustpass through corresponding numbered slots in thespreading gun slugs. Ensure that the loopsattached to the odd numbered suspension linespass through the slots in the odd number of slugs.

. Suspension lines must run free from theskirt hem, through the corresponding numberedslot in the spreading gun slugs, and to theconnector links without any dips or twists.

STRAIGHTENING CANOPY GORESWITH SPREADER GUN INSTALLED

It would be impossible for you to whip andfold a canopy with a spreading gun installed. Forthis reason you will have to straighten the goresinstead of whipping and folding. Always ensurethe safety pin is installed in the spreading gun andthe spreading gun firing lanyard is detached fromthe connector link.

1. The helper should place a shot bag on thehelper’s side of the skirt hem.

2. The packer rotates all gores on the packer’sside as a group, except the bottom gore; it goesover to the helper’s side of the packing table. Thepacker straightens and smooths the bottom goreon the packer’s side of the table throughout itslength to the peak.

3. The packer returns each gore above theshot bag on the helper’s side of the packing tableto the packer’s side, one at a time. Each fold isstraightened and smoothed, as shown in figure3-15.

4. The folded gores on the helper’s side shouldbe straightened and smoothed in the samemanner.

STOWAGE OF FIRING LANYARDINTO EXTRACTOR SLEEVE

In stowing the firing lanyard into the extractorsleeve, you must first remember not to removethe spreading gun safety pin at any time duringthis procedure.

Now you open the extractor sleeve fastenerson each side of the spreading gun safety pin;release the fastener holding the stowage sleeve tothe extractor sleeve; and remove the stowagesleeve from the extractor sleeve, as shown in

3-8

Figure 3-16.—Removing stowage sleeve.

Figure 3-17.—Inspecting firing lanyard.

figure 3-16. Inspect the firing lanyard for properstowage, as shown in figure 3-17.

In this inspection you may find that the firinglanyard has been pulled out of the stowage sleeve,or it may have been improperly stowed. To restowthe firng lanyard, cut a piece of Type I nylon cord30 inches long. This will aid you in stowing thelanyard.

Measure 7 inches from the sewn loop at thetop of the firing lanyard and make a mark. Thismark will leave you 7 inches of slack between the

sewn loop and the stowage sleeve. Form a bightthe length of the stowage sleeve in the firinglanyard, and by using the Type I cord and abodkin, pull the firing lanyard into the stowagesleeve, stopping at the bottom of the sleeve. (Seefigures 3-18 and 3-19).

Figure 3-18.—Stowage sleeve and firing lanyard.

Figure 3-19.—Stowing firing lanyard.

3 - 9

Figure 3-20.—Lanyard tacking.

Slowly remove the Type I line from the firinglanyard bight. Rapid removal of the Type I linefrom a firing lanyard bight could damage thelanyard. Form and stow an 8-inch bight of firinglanyard in the remaining stowage sleeve channelin the same manner. Tack the second lanyardbight to the stowage sleeve with one turn of waxedsize A nylon thread, single. Tie the ends with asurgeon’s knot followed by a square knot (fig.3-20).

Insert the stowage sleeve into the extractorsleeve, open end first (fig. 3-21). Engage thefastener on the stowage sleeve to the fastener onthe extractor sleeve. Engage the extractor sleevefasteners on each side of the safety pin (fig. 3-22).

INSTALLATION OF AUTOMATICPARACHUTE RIPCORD RELEASEASSEMBLY

You have read about the automatic parachuteripcord release in chapter 2 of this manual. Atthis time, you will see how it is installed into acontainer. Before you actually attempt to installa release assembly, (fig. 3-23), you must first makesure that the inspection requirements in theNAVAIR 13-1-6.2 and the NAVAIR 13-600-4-6-3have been complied with.

Now you are ready to proceed with theinstallation.

First, rotate the risers over the suspension linesand position the container on the packing tableso that the bottom end is towards the canopy and

3-10

Figure 3-21.—Inserting stowage sleeve.

Figure 3-22.—Engaging snaps.

Figure 3-23.-Automatic parachute ripcord release assembly.

the inside faces up. Attach and crimp one end ofboth short container spring opening bands to thecontainer eyes with hooks facing down (fig. 3-24).

You will find that different parachutes usedifferent lengths of arming cables. There are alsoseveral different time-delay cartridges that can beused at this time. Before you attempt to installthe arming cable or the cartridge, check theNAVAIR 13-1-6.2 to ensure you are using theright ones.

Inspect, arm, and assemble the automaticparachute ripcord release in accordance with theNAVAIR 13-1-6.2. Record the time delay, lotnumber, DODIC, part number, type of cartridge,and the expiration date on the ParachuteConfiguration, Inspection, and History Card.

Now you are ready to install the ripcordrelease into the ripcord release pocket, close theslide fastener, and secure the protector flap.

Insert the power cable through the buttonholein the top end of the container. Route the end ofthe arming cable housing through the housing portlocated in the right side of the release pocket andthrough the buttonhole located on the right sideof the container (fig. 3-25).

Close the fastener flaps of the release pocket.

Figure 3-24.-Installing retaining bands.

Figure 3-25.—Inserting power cable.

3-11

Figure 3-26.—Rotate risers.

ATTACHMENT OF CONTAINERASSEMBLY TO RISER ASSEMBLY

fol lows

To attach the container assembly to the riserassembly, you must remove the tension strap fromthe canopy peak, and remove the tension hooksfrom the connector links and the packing table.Rotate the risers onto the container, and securethe riser retainer fittings to the riser retainersupports (fig. 3-26). Now, position the lift webprotector flaps over the riser and install the breakcords. These two break cords, approximately 2inches apart, are constructed with one turn ofwaxed size FF nylon thread, doubled. Pass thethreads through the protector flap, under asupport, up through the protector flap, and tiethem snugly with a surgeon’s knot followed bya square knot, as shown in figure 3-27. Repeatthis procedure for the other riser.

INSTALLATION OF CONNECTORLINK TIES

The connector link ties are a very importantpart of the rigging of the NES-12 and otherparachutes that use the ballistic spreading gun.Not only do they prevent the risers from movingaround inside of the container, they also preventthe premature deployment of the risers (riserblowout), which could cause line entanglement orpremature firing of the spreader gun and providean anchor point for the firing of the spreader gun.

Figure 3-27.—Installing break cords.

To install connector link ties, proceed as

Cut two 12-inch lengths of 100-pound nyloncord and sear the ends. (Do not use waxed cord).Then, form a 1-inch loop in one end of each of thecords and secure with a bowline knot. Tie an over-hand backup knot in the end of the cord (fig. 3-28).

Figure 3-28.—Connector link ties.

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Figure 3-29.—Tying connector links.

Now position the connector links side by side sothat the top connector links are to the right of thebottom connector links, then form a noose aroundthe connector links located on the helper’s sidewith one of the 100-pound tie cords, as illustratedin figure 3-29.

Tighten the noose and tie the free end of thetie cord to the bottom inboard cloth retainingband loop with three to four half-hitches. Trimexcess cord.

Using the other tie cord in the same manner,secure the connector links on the packer’s side.

INSTALLATION OF RELEASEASSEMBLY LANYARD AND RIPCORDASSEMBLY

Proceed in installing the lanyard release andripcord assemblies by marking the clamp releaselanyard 36 inches from the locking pin end. Next,fold the top end flap onto the container so thatthe baseplate faces up.

WARNING

ENSURE THAT THE BASEPLATECLAMP IS POSITIONED OVER THEHEX NUT PRIOR TO INSTALLINGTHE LOCKING PIN (FIG. 3-30).

Figure 3-30.—Release lanyard assembly.

Now, position the clamp over the end fittingof the power cable housing. Insert the baseplatescrew through the clamp holes and into the right-hand baseplate hole so that the clamp flange fitsover the end of the baseplate, shown in figure3-30.

Position the large slotted end of the baseplateclamp under the screwhead on the baseplate.Position the manual ripcord housing and powercable housing under the clamp with two flat sidestogether and the other two flat sides positionedagainst the baseplate. Place the clamp in theclamping grooves of the two housings. Positionthe small slotted end of the baseplate clamp overthe baseplate stud. Insert the release lanyardlocking pin into the stud hole. Secure the clampin place. The locking pin should be finger tight;if necessary, slightly loosen the screw. Ensure the

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two housings are correctly positioned andsecurely retained. Safety-tie the locking pinto the stud with one turn of waxed sizeFF nylon thread (V-T-295), single. Pass thethread through the lanyard knot and tie theends with a surgeon’s knot, followed by a squareknot.

The next procedure is to insert the topripcord pin through the beveled side ofthe eye in the power cable. Route the lan-yard over the helper’s side of the top endflap V. Tack the lanyard to the top endflap at the V with 1/8-inch slack betweenthe locking pin and the tacking, passingthe tacking around the lanyard. Use one turn ofwaxed size E nylon thread, single. Tie its ends witha surgeon’s knot, followed by a square knot (fig.3-31).

Route the lanyard along the inside of the topend flap to the helper’s side of the automaticactuator power cable buttonhole. Tack thelanyard to the upper edge of the container withone turn of single, waxed, size E nylon thread(fig. 3-32), allowing 1/8 inch of slack between thetackings. The tacking must pass around thelanyard and not through it. Tie the ends with asurgeon’s knot, followed by a square knot.

Figure 3-31.—Tacking locking pin.

Figure 3-32.—Tacking release lanyard.

Reeve the lanyard through the lanyard guidegrommet (fig. 3-33). Place the 3`6-inch markon the lanyard over the bar on the inboardconnector link located on the helper’s side.Secure the lanyard to the connector link barwith a bowline knot. Ensure the lanyard ispositioned between the webbing and the connectorlink end. Tie an overhand backup knot in the endof the lanyard.

You should have the QA inspect your workat this point.

ATTACHMENT OF FIRINGLANYARD TO SUSPENSIONLINE CONNECTOR LINK

Before attaching the firing lanyard, ensure thatthe safety pin is installed in the spreading gun.Then starting at the gun, route the firing lanyardbetween suspension lines 7 and 8. Slide the canopytowards the container and form an S-fold in thesuspension lines large enough to allow the loopin the end of the firing lanyard to align with itsconnector links. Be careful to check to see thatno suspension lines are dropped from theconnector link bar.

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link. This was done to prevent the torquingfrom being missed if you were only per-forming one of the many operations thatrequire you to remove and replace the yokeand plate. If you have performed all theoperations described, then, at this time, youdo the final torquing before the suspensionlines are placed into the container. There-fore, it is very important that you completethis process in the following manner and have itinspected.

Remove the yoke and plate assembly on theoutboard top connector link located on thehelper’s side. Insert the connector link bar throughthe loop in the firing lanyard and reattach theyoke and plate assembly. Tighten the screw to atorque value of 20 to 25 pound-inches. Apply atamper dot to the connector link screwhead usinglacquer (TT-L-32, color 11136, insignia red orequivalent).

Figure 3-33.—Reeving release lanyard.

As you have read this chapter on the NES-12,you may have noticed that each time you haveremoved the yoke and plate assembly from theconnector link, you have been told to tighten andtorque the screw when reassembling the connector

At this point, you have completed therigging and you are ready for the packingprocedure.

When actually performing any of theseprocedures, you should refer to the NAVAIR13-1-6.2 and NAVAIR 13-600-4-6-3. Also, youwill find that some of your rating exam questionswill be taken from these NAVAIR manuals.

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CHAPTER 4

AIRCREW PERSONAL PROTECTIVEEQUIPMENT

Learning Objective: Upon completion of this chapter, you will be able torecognize, inspect, and maintain aircrew personal protective equipment.

Aircrew flight clothing plays an essential rolein the safety and survival of Navy aircrewmen.It protects them from the elements and providesnecessary comfort for efficient mission per-formance. Its primary function is to protect themagainst hazards such as fire, heat, cold, andimmersion in water. Different combinations ofprotective clothing and equipment are used forvarious flight, emergency, and environmentalconditions.

Naval aircrew protective equipment has alsobeen designed to provide camouflage and otherescape and evasion design features. Because of thewide range of environmental conditions in whichaircraft must operate, a compromise betweencomfort and protection has, in some cases, beennecessary. Postcrash fire and emergency coldwater exposure are two critical areas whereoperational requirements are more important thanflight comfort. Emphasis has been placed ondeveloping materials and clothing assemblies thatimprove survival chances and, specifically,minimize injuries and prevent loss of life in caseof an aircraft accident in either normal or hostileenvironments.

As an Aircrew Survival Equipmentman, someof your responsibilities are the care and main-tenance of protective equipment. You may berequired to order, inspect, modify, and repair thisequipment.

facilities, trained personnel and operational needsare the basic considerations in determining thelevel to be used.

Maintenance is divided into two categories—preventive and corrective. Preventive maintenanceis the care and servicing needed to maintainequipment and facilities in satisfactory operatingcondition by providing for systematic inspection,detection, and correction of failures either beforethey occur or before they develop into majordefects. Corrective maintenance is performed asa result of failure of the part/equipment, or tocorrect defects discovered during preventivemaintenance.

Upon completion of any maintenance action(for example, inspections, repairs, modifications),you must make appropriate entries on theapplicable maintenance documents. By properlymaintaining these documents, you provide acomplete maintenance history of the equipmentthroughout its service life.

The maintenance/material control officer,using the guidelines of OPNAV 4790.2 (series),schedules the preventive maintenance of allaircrew personal protection equipment for whichhe is responsible. Maintenance of this equipmentmust be thorough at all times. No carelesstreatment or willful neglect of aircrew personalprotective equipment will go unnoted. The vitalfunction of the equipment must be uppermost inthe minds of all personnel concerned.

MAINTENANCE SCHEDULINGAND RECORDS

MAINTENANCE DOCUMENTSPlanned maintenance of protective flight

clothing is performed at the level of maintenanceset forth in OPNAVINST 4790.2 (series). Thelevels of maintenance are either organizational,intermediate, or depot. Mission, time, equipment,

Maintenance documents provide a systematicmeans of recording equipment history anddocumenting all maintenance actions performedon the equipment.

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These documents consist of the following:

. Aircrew Personal Protective EquipmentHistory Card, NAVAIR 10470/11, S/N: 0102-613-9110

. History Card—Aviation Crew Systems,OPNAV 4790/138

. Shop Process Cards

. Maintenance Data Collection SystemForms, which include the following:

1.2.

3.

VIDS/MAF, OPNAV Form 4790/60Support Action Form, OPNAV Form4790/42DOD Single Line Item RequisitionSystem Document

. Aircrew Personal Protective EquipmentManual, NAVAIR 13-1-6.7

NOTE: All entries must be printed clearlywith blue or black ball-point pen, ortypewritten. Felt-tip pens or pencils areunacceptable for maintenance documentor history card entry purposes. When yousign a maintenance document or historycard, your full signature is required. Besure to check the OPNAVINST 4790.2(series) for the most up-to-date formnumbers.

Aircrew Personal ProtectiveEquipment History Card

This Aircrew Personal Protective EquipmentHistory Card contains information pertaining tothe personal protective equipment issued to onespecific aircrew member. The card is divided intothree sections: Section I records all aircrewpersonal equipment issued to the aircrew member.Section II is used for recording when calendarinspections are performed. It includes the in-spector’s full signature and collateral dutyinspector (CDI) stamp. Section III records allmodifications and repairs performed on theequipment. This card can be used as a custodycard by units which operate a flight gear issuepool. When a new card is started for any reason,the old card is stapled on the back of the new card.When an aircrew member transfers to a new unitand keeps his personal protective equipment, thecard is forwarded to his new unit.

History Card—Aviation Crew Systems

The Aviation Crew Systems History Cardcontains all information pertinent to a piece

of equipment. All maintenance tasks performedon the equipment (repairs, modifications,inspections) are recorded on the history card.In addition, the inspection cycle interval isentered in the upper right-hand corner of thecard face. The record includes the Julian dateand signature of the person accomplishing themaintenance task and the CDI’s signatureand number in the inspector’s signature column.When, for any reason, a new card is initiated, theold card must be retained and stapled to the backof the new card. If the history card has been lost,initiate a new card using information from themanufacturer’s nameplate. The history card mustaccompany the equipment to the intermediate- ordepot-level maintenance activity. Whenever apiece of equipment is transferred from one unit toanother, an updated history card is forwarded tothe receiving unit. The card is placed in a suitableenvelope and securely attached to the item. If thepiece of equipment is an aircraft inventory item,the history card is inserted in the inventorylogbook. If the receiving unit fails to receive thehistory card, a formal request for the card mustbe sent to the forwarding unit.

Shop Process Cards (SPC)

The Shop Process Cards (SPC) provide themaintenance man with a ready reference for per-forming scheduled maintenance on a specific typeof aircrew personal protective equipment. EachSPC contains one or more detailed maintenancerequirements. Illustrations, clearances, tolerances,charts, and part numbers are included when re-quired. The minimum requirements for the per-formance of all or part of any particular periodicmaintenance task (calendar or special inspection)are contained in a set of these cards. The workplan (or order of performing the maintenancework requirements) is prearranged, and is issuedby the work center supervisor for the type ofaircrew personal protective equipment beingserviced.

Maintenance Data Collection System Forms

The following forms used in the NavalAviation Maintenance Program are applicable tothe aircrew personal protective maintenance:VIDS/MAF Form, Support Action Form, DODSingle Line Item Requisition System Documents,and Work Request Forms. Proper completion isessential to the function of the program.Instructions on their use can be found in the NavalAviation Maintenance Program, OPNAVINST4790.2 (series), and in the Aviation MaintenanceRatings Manual 3 & 2, NAVEDTRA 10342-1.

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Aircrew Personal Protective EquipmentManual, NAVAIR 13-1-6.7

When you are working with personal pro-tective equipment, your best friend is theAircrew Personal Protective Equipment Manual,NAVAIR 13-1-6.7. This manual contains com-prehensive and authoritative information onconfiguration, application, function, inspection,and maintenance of aircrew personal protectiveequipment.

MODIFICATIONS OF FLIGHTEQUIPMENT

Perform only authorized modifications. Un-authorized modification and deviations from theapproved configuration of life support andsurvival equipment by individual crewmen couldcreate unknown and possibly dangerousconditions.

NAVAIRSYSCOM is the only authority formodification to life support equipment andsurvival equipment. Such changes are usuallyaccomplished by the cognizant field activity (CFA)via Aircrew System Changes or a change to theequipment procurement package. The NAVAIR13-1-6.5 also permits an operating activity, withapproval of the controlling custodian, toconditionally modify ONE unit of equipment inservice to correct or overcome unsatisfactoryconditions in that equipment item. Any other typeof deviation, peculiar configuration, ormodification to life support and survivalequipment is not allowed at the operating level.The squadron riggers have no authority orresponsibility y to perform them.

If there is a conflict between CFA documentsand NATOPS requirements, or if there is a needfor clarification of equipment configuration orif equipment deficiencies are discovered, the CFAshould be notified. The field activity havingcognizance of most of the life support andsurvival equipment is the Naval Air DevelopmentCenter (NAVAIRDEVCEN) at Warminster,Pennsylvania. For parachutes and relatedhardware, including torso harness, the CFA is theNaval Weapons Center (Code 6412), China Lake,California, 93555.

NADEP Pensacola has cognizance over allsurvival radios and URT-33 emergency beacons.

TYPES OF FLIGHT CLOTHING

The flight clothing covered in this chapter isdesignated to be worn by aircrew members asouter garments while on flight operations in

aircraft. As a squadron aircrew survival equip-mentman, you maybe asked to sew on squadronpatches, name tags, and rate insignias. These itemsare authorized to be worn on flight clothing asdirected by the local command. However, thetotal surface area of all patches (name tagexcluded) may not exceed 50 square inches, andno one patch may be bigger than 4 inches in anygiven direction.

SUMMER FLYER’S COVERALLCWU-27/P AND BLUE FLYER’SCOVERALL CWU-73/P

The CWU-27/P summer flyer’s coverall andthe CWU-73/P blue flyer’s coverall (fig. 4-1) are

Figure 4-1.-Summer flyer’s coverall, CWU-27/P and blueflyer’s CWU-73/P.

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designed to be worn as an outer garment in warm-temperature zones, and they provide protectionin the event of an aircraft fire. They are designatedfor use by all aircrew members.

Configuration

The coveralls are one-piece, unlined garmentsthat are made of Aramid cloth, which is a high-temperature resistant, inherently flame-retardant,synthetic fabric with no hot-melt point or dripcharacteristics. This lightweight fabric does notsupport combustion, but begins to char at 7000to 800 “F. The fabric has abrasion resistancesimilar to nylon, and like nylon, Aramid isnonabsorbent. Because of this characteristic,cotton underwear should be worn under thecoverall for optimum comfort. The color of theCWU-27/P is sage green, and the CWU-73/P isblue.

The CWU-27/P and CWU-73/P (fig. 4-1)have a slide fastener (zipper) front closure, sidepass-throughs, biswing back, and hook and pilefastener size adjustments at the end of each leg.Also included are two breast patch pockets, onecombination cigarette and multiple pencilcompartment on the upper front left sleeve, andtwo thigh pockets. The CWU-73/P has epauletsto allow attachment of shoulder boards. Exceptfor the knife pocket on the left thigh and themultiple pencil compartment pocket on the rightlower leg, all pockets and pass-throughs havebutted, beaded, covered, slide fasteners. If a hookblade knife (shroud cutter) is carried, it shouldbe tied to the pocket cord and stowed in the knifepocket with the hook blade open for emergencyuse.

Fitting

The coveralls are fitted to the aircrew member,and their size normally corresponds to men’sregular suit sizes. The coveralls are used withstandard Navy personal equipment and may beworn over or under the anti-g garment. Thecoverall sleeves should always be worn down andclosed at the wrist to ensure maximum fireprotection.

Maintenance

The aircrew member’s responsibility formaintenance of the coverall is limited to cleaning.The coveralls are inspected for general conditionat intervals not to exceed 90 days. Repairs

performed at the organizational level are restrictedto repairing open seams, small holes or tears,replacement of hook and pile fastener tape, andreplacement of slide fasteners.

Only high-temperature resistant Aramid cloth(MIL-C-81280) and high-temperature resistantnylon thread (MIL-T-83193) should be used forrepairs.

A new coverall should be laundered before useto soften the fabric and eliminate any possible skinirritation that might occur due to original fabricharshness. After tumble drying or during dripdrying, the coverall should be hung on a woodenhanger. The fabric is a drip-dry type that requiresno special handling, and it may be washed asfrequently as needed. The coverall may belaundered by the aircrew member at home or ina commercial-type washer and dryer. Launderingin water up to 140°F and tumble drying up to180°F does not damage or shrink the coveralls.

Use of a commercial fabric softener in therinse cycle removes body oils during the launder-ing process. The fabric softeners also stopstatic cling. Ironing or pressing is permissible.However, it is difficult to remove wrinkles orcreases due to the high-temperature resistantqualities of the material. Coveralls that are heavilysoiled and\or stained with oil or grease may becleaned with solvents normally used in commercialdry cleaning establishments. Dry cleaning orlaundering does not compromise the flame-retardant properties, and no renewable flame-retardant treatment is required.

FIRE-RESISTANT FLYER’SGLOVES, GS/FRP-2

The fire-resistant flyer’s glove (MIL-G-81188)is designated for use in warm-to-moderatetemperature zones and provides protection in theevent of aircraft fire. They are used by all aircrewmembers (fig. 4-2).

Configuration

The gloves are snug fitting and designed toprovide maximum dexterity and sense of touch.If properly fitted they should not interfere withthe operation of the aircraft and use of survivalequipment. The gloves are available in sizes 5 to11. Since the fabric is stretchable, the sizes willaccommodate any size hand. The gloves areconstructed of soft cabretta gray leather (palm andfront portion of fingers), and a stretchable, sagegreen, lightweight knit Aramid fabric (entire back

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Figure 4-2.—Fire-resistant flyer’s gloves, GS/FRP-2.

of hand). The cloth portion of the gloves will notmelt or drip, and it does not support combustion.The fabric does begin to char at 700° to 800°F.

Fitting

The fire-resistant flyer’s glove normallycorresponds to the aircrew member’s glove size.Determine the proper size glove on a trial fit basis.The glove must fit snugly.

Maintenance

It is the aircrew member’s responsibility toclean the gloves. Repairs or other maintenanceactions are performed at the organizational levelor above, and are limited to restitching seams. Thegloves are laundered as follows:

1. Put on the gloves and wash with a mildsoap in water not over 120°F as if washing hands.When the gloves are clean, rinse and remove themfrom your hands. Squeeze, but do not wring thegloves to remove excess water. Never use ableaching compound.

2. After removing excess water, place thegloves flat on a towel and roll the towel to coverthe gloves. Ensure that the gloves do not contacteach other and are not exposed to hot air orsunlight.

3. Letting the gloves come in contact witheach other may harm the soft leather palms. Theexposure to hot air or sunlight could cause thegloves to shrink.

Figure 4-2.—Flyer’s boot.

FLYER’S BOOT

The impact-resistant flyer’s boot (fig. 4-3) isdesigned to protect the aircrew member’s footagainst high-impact forces. The boot is water-resistant.

Configuration

The upper boot is black in color and isconstructed of high quality calfskin. The innerliner is made with soft, full grain, glove leather.The boot is 8 inches high when fully laced, andis available in sizes 4 narrow through 14 1/2 extrawide. The traction tread outsoles and heels are

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made of nonslip, nonmarking, jet-fuel-resistantrubber. The steel box toe is constructed of cold-rolled carbon steel to provide a safety marginthrough greater compression resistance. The bootis designed for use by all aircrew members.

Fitting

The boot is fitted to the aircrew memberand normally corresponds to his regular shoesize.

Maintenance

The aircrew member is responsible for main-tenance of the boot. Maintenance is limitedto cleaning and polishing. Polish used foreveryday care of shoes is acceptable. There areno authorized repairs, as the sole and heel shouldoutwear the upper boot. Broken or worn lacesmay be replaced.

SV-2 SURVIVAL VEST

The SV-2B survival vest provides maximumuseful storage for survival equipment, consistentwith minimal bulk and weight. In addition, thesurvival vest provides for integration of a lifepreserver, anti-g coveralls, and the chest-mountedoxygen regulator. It does not interfere with useof either the regular or integrated-type parachuteharness. The SV-2B vest is the latest authorizedconfiguration for this series of survival vest.

Configuration

The SV-2B survival vest is constructed basi-cally of nylon cloth. An adjustable harness,leg straps, and an entrance slide fastener providea means of fitting and securing the vest to theaircrew member. Elastic straps on the rear allowgreater comfort and mobility of the wearer.Pockets are provided for stowage of survival items(fig. 4-4). When required, the chest-mountedoxygen regulator is located inside a pocket securedto the vest by means of hook and pile tape.

Fittings

The basic SV-2B survival vest is designed tofit chest sizes from 40 to 48 inches. By changingthe elastic straps on the rear, the vest may beadapted to a wider size range. To fit an SV-2Bproperly, have the aircrew member wear all hisnormal flight gear, including the MA-2 torsoharness, if used. Put the SV-2B vest on as if it

were a jacket. Pass the leg straps through thecrotch and attach the snap hooks. Adjust the legand shoulder straps so that they are snug and thebottom of the vest is just above the hips. Examinethe SV-2B for proper fit. If it is too loose, theelastic straps must be shortened. If it is too tight,you must lengthen the elastic straps. The pro-cedures for this adjustment, as well as main-tenance, calendar inspections, and cleaning,are covered in-depth in the Aircrew PersonalProtective Equipment Manual, N A V A I R13-1-6.7.

ANTIEXPOSURE ASSEMBLIES

Antiexposure assemblies are composed ofseveral garments that protect the aircrew memberin the event of immersion. Constant wearassemblies provide additional protection fromcold weather. The constant wear assembliesconsist of a waterproof outer garment worn overa ventilation liner and/or cold weather underwear.

The quick-donning antiexposure suit is carriedin the aircraft, and donned only in case ofemergency. It consists of a waterproof outergarment equipped with permanently attachedboots and wrist and neck seals. An inflatable hoodand antiexposure mittens are stowed in thepockets. In case of emergency, the assembly isdonned over the regular flight clothing.

Either continuous-wear or quick-donningantiexposure suits, as appropriate, are providedfor flight personnel and passengers when there isa significant risk of crashing in the water, andwhen any of the following conditions prevail:

1. The water temperature is 50°F or below.2. The outside air temperature (OAT) is 32°F

(wind chill factor corrected) or below.

If the water temperature is between 50° and60°F, the commanding officer of the unitconcerned considers the following search andrescue (SAR) factors:

1. The maximum probable rescue time. Thisshould be a function of mission distance, SARequipment, and SAR location.

2. The lowest temperatures that will occur inthe mission area during the time period of theflight.

3. Then by using table 4-1, he determineswhether antiexposure suits are required.

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Figure 4-4.—SV-2B survival vest.

Table 4-1.—Antiexposure Suit Requirements

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4. When water temperature is below 60°Fand antiexposure suits are not required, theflight equipment includes antiexposure, high-temperature resistant undergarments. Wearingdouble layers of these undergarments can signi-ficantly improve antiexposure protection.

A/P22P-6(V)2 and A/P22P-6A(V)2Antiexposure Assemblies

The A/P22P-6(V)2 and the A/P22P-6A(V)2antiexposure assemblies (fig. 4-5) are continuous

wear assemblies designed to keep the wearerdry. The complete assemblies provide protectionfrom the thermal effects of cold water immersionin the event of emergency overwater bailout.The assemblies differ only in the type ofliner that is worn. The A/P22P-6(V)2 as-sembly uses the CWU-23/P liner, and theA/P22P-6A(V)2 assembly uses the CWU-72Pliner. Table 4-2 lists the components that makeup the A/P22P-6(V)2 and the A/P22P-6A(V)2antiexposure assemblies.

Figure 4-5.—A/P22P-6(V)2 and A/P22P-6A(V)2 antiexposure apparel assemblies, constant wear.

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Table 4-2.—A/P22P-6(V)2 and A/P22P-6A(V)2 Anti-exposure Apparel Assemblies

The A/P22P-6(V)2 or the A/P22P-6A(V)2antiexposure assembly should be worn by aircrewmembers for flight operations in accordance withthe climatic and operational requirements estab-lished by the NATOPS General Flight and Opera-tional Instructions Manual, OPNAVINST 3710.7series.

The A/P22P-6(V)2 and the A/P22P-6A(V)2antiexposure assemblies are intended to providethe aircrew member with a lightweight coverallassembly that allows for the performance of allrequired flight operations without restricting anybody movements. The coveralls are moisture/vapor permeable to prevent excessive buildup ofbody heat. In the event of immersion in water,the suit fabrics will not allow water to enter,keeping the wearer dry. All components of theassembly must be worn to achieve the greatestlevel of exposure protection.

The A/P22P-6(V)2 and the A/P22P-6A(V)2antiexposure assemblies should be properly sizedto the aircrew member based on his height,weight, and chest measurements. You woulddetermine the chest circumference by taking a tapemeasurement at nipple height with the aircrewmember wearing one cold weather undershirt.Refer to the Aircrew Personal ProtectiveEquipment Manual, NAVAIR 13-1-6.7, forproper sizes.

CWU-23/P LINER. The CWU-23/P liner(fig. 4-6) is a one-piece garment that is suppliedin 12 sizes. The liner is worn directly under theCWU-62/P antiexposure coverall, and over therecommended underclothing. The liner provides

Figure 4-6.—CWU-23/P liner.

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Figure 4-7.—CWU-72/P liner.

an inner layer of 100% cotton and an outer layerof polypropylene netting.

Each sleeve ending has a coated stretch fabricinsert to permit easy insertion of the hands andto reduce bulk. The leg endings are short enoughto clear the tops of the flight boots, therebyeliminating bulk. They are notched at the frontto allow standard wool or cotton socks to bepulled up over the liner legs, and to hold the linerlegs in place when the CWU-62/P coverall isdonned.

CWU-72/P LINER. The CWU-72/P liner(fig. 4-7) is a one-piece garment and is suppliedin nine sizes. The liner is worn directly under theCWU-62/P coverall and over the recommendedunderclothing. The liner provides a layer ofthermal protection, and is made of 100% olefinmicrofiber thermal insulation sandwiched betweentwo layers of high-temperature resistant Aramidfabric.

CWU-62/P ANTIEXPOSURE COVER-ALL.— The CWU-62/P antiexposure coverall(fig. 4-8) is a one-piece garment and is suppliedin 12 sizes. The coverall should not be worn indirect contact with the skin. It is a lightweightcoverall that prevents water from entering, butpermits bodily produced moisture vapor to passout, thus minimizing heat and moisture buildup.Proper maintenance is essential to the life andsafety of this coverall, as well as proper sizing andfitting. The neck seal and wrist seals are

manufactured from natural rubber and areflocked on both sides. The entrance opening andthe relief portal are sealed with a water andpressure-sealing slide fastener.

To fit the CWU-62/P coverall, the neck andwrist seals may be trimmed at the initial fitting,but the seals tend to adjust to the aircrew memberafter a short period of time. If no excessive sealrestriction exists, and the seal fit is acceptable tothe aircrew member, the seals should be left asthey are. Neck seals need to fit snugly and remainin direct contact with the neck through all normalhead movements. Wrist seals must fit tightlyenough to prevent water entry, but not tightenough to restrict blood flow. If seal sizing isrequired, proceed as follows:

CAUTION

DO NOT USE A BALL-POINT PENOR LEAD PENCIL TO MARK THECOVERALL MATERIAL. USE ONLYTAILOR’S CHALK OR A CHINAMARKING PENCIL.

1. If neck seal trimming is necessary, marka line around the circumference of the neckopening. Trimming increments should not bemore than one-eighth inch at a time.

2. Carefully cut along this line with a sharppair of scissors.

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Figure 4-8.—CWU-62/P antiexposure coverall.

3. Trim the wrist seals in the same way as theneck seal, except the trimming increments mustnot exceed one-third inch at a time.

4. After trimming the seals, have the aircrewmember put on the coveralls to determine the sealrestriction and the water-sealing characteristics.If any adjustments are necessary, you must repeatsteps 1 through 3.

SRU-2WP RUBBER SOCKS.– The SRU-25/Prubber socks are supplied in eight sizes. Therubber socks are one-piece and are molded toshape to provide comfort and a good fit. The topsof the socks extend above the flight boots toreduce bulk and restriction.

The size of the SRU-25/P rubber socks willbe governed by the size of the flight boot to beused. Usually, a rubber sock one size smaller thanthe boot to be used will provide an acceptable fit.The aircrew member should wear a pair of heavywool socks, then put on a pair of SRU-25/Prubber socks corresponding to his normal bootsize. The rubber socks should be worn in a slightlystretched condition to prevent wrinkles or bulk

in the boot, but they must not be too tight. Largeror smaller rubber socks and/or boots may berequired for a proper fit.

To fit the rubber socks, select the correct sizeof rubber socks and fit them to the CWU-62/Pcoveralls as follows:

1. Have the aircrew member put on theantiexposure assembly (except the hood, mittens,and flight suit), the MA-2 torso harness, ifapplicable, and a pair of properly fitted, heavywool socks.

2. Mark the coverall legs and socks (L and R)on the inside and front and back. This is to ensurethe socks are matched to the correct leg duringinstallation.

3. Have the aircrew member sit in a straight-back chair with his legs drawn back, heels directlybelow the kneecaps, and his feet flat on the floor.

4. Turn the top 2 inches of sock down,forming a temporary cuff. Mark the circum-ference of the coverall legs where they meet the

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Figure 4-9.—Fitting the SRU-25/P rubber socks.

top of the folded socks (fig. 4-9). Have the aircrewmember take off the coveralls. Remove the top2 inches of the socks with a pair of sharp scissors.

5. Remove excess material from the coverallleg by cutting a line 1 inch below the mark thatwas applied in step 4. Ensure the leg is cutperpendicular to the lengthwise direction of theleg. Make your alignment marks at the front ofthe coverall legs and socks to ensure the socks willbe properly aligned with the legs during theattachment process.

6. Turn the coveralls inside out and lay themflat, facing up.

NOTE: When you attach the socks to thecoveralls, the right sock is on the right legand the left sock is on the left leg.

7. Insert the sock into the leg opening, so thatthe right sides of the sock and coverall leg arefacing each other, and the toe is pointing up(toward the front) (fig. 4-10).

Figure 4-10.—Attaching the rubber sock to the coverall leg.

8. Beginning at the front of the leg, makesure the alignment marks are matched. Thenattach the sock with one row of stitches, one-fourth inch from the cut edges, five to sevenstitches per inch, using nylon size E thread.Overlap the stitching one-half inch. Do notbackstitch.

9. Fold the cut edges of the seam over thesock. Make the fold as near the stitch line aspossible. Apply one layer of 1 1/2-inch seam tapeover the seam, keeping the stitch line and the cutedges as nearly centered under the tape as possible.Overlap the ends of the seam tape 1 inch.

10. Additional information on maintenanceprocedures, inspection cycles, and test equipmentfor antiexposure assemblies is covered in theAircrew Personal Protective Equipment Manual,NAVAIR 13-1-6.7.

ANTI-G GARMENTS

Although there is no limit to the speed ahuman can endure in straight and level flight inan aircraft, changing speed or direction canproduce inertia to which the body has a sharplylimited tolerance. In the case of extreme stressesexerted by forces of the type met in seat ejection,ditching, or parachute opening shock, the shortduration of the force restricts its effects. However,changing the direction of flight often producesstress forces equal to several times the normalvalue of gravity for periods longer than a second.These forces can have dangerous effects.

At 5 g’s (five times the force of gravity), thepilot’s body is exposed to a force that increasesits weight and that of its components five times.This increased weight has many effects. The pilotis pushed down into his seat. His arms and legsfeel like lead, and manipulation of the controlsbecomes more difficult. In addition, the extraweight of the internal organs causes abdominaland chest discomfort. Most important, however,is the effect on the circulatory system.

At 5 g’s the pressure exerted by the columnof blood between the head and the heart becomesjust about equal to the blood pressure in thearteries. As a result, the pressure supplied by theheart is not great enough to pump an adequatesupply of blood to the head.

To counteract these effects, the pressure in thearteries must be increased above the heart level.At the same time, distended vessels and tissue andfluid spaces in the regions below the heart must

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be restored to normal. This is accomplished bythe anti-g garment.

With the anti-g system, compressed air ismetered to the garment in proportion to thegravitational force being exerted. The bladders ofthe garment inflate, compressing the legs andabdomen of the wearer by an amount alsoproportional to the gravitational force. Thus, thegarment prevents blood collecting in the abdomenand lower extremities and forces blood from thelower to the upper part of the body. Thiseffect increases blood flow to the heart andincreases resistance to the shifting of bloodto the lower limbs. In addition, it raises thediaphragm, decreasing the distance between theheart, the eyes, and the brain. Altogether, itincreases the tolerance of the pilot an average ofabout 2 g’s.

Without an anti-g garment, the average pilotcan withstand 4.5 to 5.5 g’s without losing visionor blacking out. With a garment, he is capableof withstanding 6.0 to 7.0 g’s. However, thisprotection is available only for sustainedaccelerations of 4 to 5 seconds or longer inmaneuvers other than snap maneuvers.

Anti-g equipment does not offer protection insnap maneuvers where 10 to 12 g’s can be appliedin approximately 1 second. Such brief forces arenot as harmful to the body as lesser forcessustained for a number of seconds.

CSU-15/P ANTI-G GARMENT

The CSU-15/P anti-g garment (fig. 4-11)consists of a fire-resistant Aramid cloth outershell, which houses a bladder. It is cut away atthe buttocks, groin, and knees. The outer shellhas waist and leg entrance slide fasteners, sixadjustment lacing areas with lacing covers, andtwo easily detached leg pockets with slide fastenerclosures. The bladder system is constructed ofpolyurethane-coated nylon cloth and covers theabdomen, thighs, and calves. The bladder systemis fitted with a hose for connecting directly to theaircraft anti-g system. This anti-g garment isavailable in six sizes.

CSU-15/P anti-g garments are issued toindividual aircrew members, and are used inconjunction with standard Navy personalequipment.

Fitting the CSU-15/P Anti-g Garment

The CSU-15/P anti-g garment is fitted and ad-justed to the aircrew member on a best-fit basis.

Figure 4-11.—CSU-15/P anti-g garment.

The cords are laced in the same directionas the applicable lacing slide fastener closure.With a proper fit, the lace adjustment shouldbe tightened approximately halfway, and thecutout should expose the knees, groin, andbuttocks without binding or hindering movement.The garment should fit snugly, but not tight, withthe bladder deflated. The inflated bladder shouldcompress the waist, thighs, and calves firmly andevenly.

With bladder deflated, lace adjustments aretightened to provide a snug (not tight) comfortablefit, especially at the waist.

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Installing The CSU-15/PAnti-g Garment Hose

This anti-g hose also must be cut to size, andan end fitting installed after correct garment sizehas been determined. To fit the anti-g hose,proceed as follows:

Have the aircrew member don the anti-ggarment and sit in the aircraft. Attach the quickdisconnect on the hose to the aircraft supplysystem. If the hose is too long, measure it andmark where to cut it.

Lay the hose out flat. In a single operation,cut the outer covering, inner hose, andspacer/reinforcement at the mark. Searcompletely around the end of the outer cover toprevent fraying.

Remove the tape, clamp, and severed portionof hose from the quick-disconnect connector.

Position the spacer/reinforcement on therubber extension of the connector (fig. 4-12). Buttthe end against the raised portion of theconnector, and cover it with three turns ofelectrical tape.

Slide the inner hose (bladder material) over theconnector and butt it against the raised portionof the connector. Ensure the spacer/reinforcementis not twisted. Secure it with three turns of tape.

NOTE: In some instances it may benecessary to build up the outside diameterof the hose area under the clamp with threeto six turns of tape to get the clamp tight.

Slide the outer cover of the hose over the innerhose until it butts against the raised portion ofthe connector. Install a clamp as shown in figure4-12. Cover the clamp with three turns of tapeor a heat-shrinkable insulation sleeve.

Figure 4-12.-Assembly of hose and quick-disconnect fitting.

Finally, ensure that the fitting is properlyinserted in the hose, and clamp it properlypositioned between the raised bead and the body.Ensure that the clamp is tightened sufficiently bygrasping the hose and fitting and jerking sharply.

Inspections

A preflight inspection is performed by theaircrew member before each flight. The intervalbetween preflight inspections must not exceed 14days. To perform the preflight inspection, do thefollowing:

l Check the slide fasteners for secureattachment, ease of operation, and corrosion.

l Visually inspect all seams for loose orbroken stitching.

. Visually inspect outer shell and hosecovering for holes, tears, and abrasion.

. Check the quick-disconnect connector fornicks, corrosion, and proper operation.

. Inspect the laces and lacer loops for secureattachment and excessive wear.

If you find any discrepancies, forward thegarment to the aviator’s equipment branch for aperiodic inspection.

The calendar inspection is made by anAircrew Survival Equipmentman prior to placingthe anti-g garment in service and every 180 daysafter that, which coincides with every second lifepreserver calendar inspection. The calendarinspection is also done whenever a discrepancy isdiscovered during preflight inspection. Thisinspection consists of the preflight inspectionitems and the following additional tasks:

You will be required to perform a leak test andrepair any discrepancies found after you completethe leakage test.

To perform the leakage test on a CSU-15/Panti-g garment, you should use a special testfixture, which inflates the suit and measures theinside pressure. You are required to inflate theg-suit to 5 psi. The bladder must not drop morethan 1.0 psig in 30 seconds. A pressure dropgreater than 1.0 psi in 30 seconds constitutes afailure. The CSU-15/P anti-g garment remains inservice until it fails the leakage test.

If everything is in order, date and sign thehistory card.

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MAINTENANCE

Repairs are performed at the lowest level ofmaintenance possible. They are limited torepairing small holes and tears in the outer shelland replacement and adjustment of lacings. Sincethe hose is part of the bladder system, repairs toit are limited to tightening or replacing the clampand replacement of quick-disconnect fittings.

Cleaning is performed at the lowestmaintenance level possible. TO clean theCSU-15/P anti-g garment, proceed as follows:

1. Seal the air inlet port with a cork or arubber stopper. Do NOT allow water to enter thebladder. NEVER machine-wash or dry clean theanti-g coveralls.

2. Immerse the garment in a solution of bacter-iostatic detergent and cold water. Do not wash thegarments in hot water. Mix the detergent accordingto the instructions printed on the container. If

instructions are not printed on the detergent con-tainer, use a ratio of 1 cup detergent to 3 gallons ofwater. Allow to soak for 5 minutes. Agitate gently(by hand) for 2 minutes and drain the water.

3. Rinse in cool, fresh water, and then drainthe water. Repeat the rinse process until all tracesof detergent have disappeared from the rinse water.

4. To dry the garment, it is very importantthat you do not try to wring, tumble, or spin drythe garment. This action could damage thebladder or air inlet port. The proper procedurefor drying is to hang the garment on a woodenhanger in a dry, well-ventilated area. Do not drythem in direct sunlight because ultravioletradiation can weaken the fabric.

INTEGRATED TORSO HARNESSES

The MA-2 integrated parachute-restraintharness (fig. 4-13), also known as the integrated

Figure 4-13.–MA-2 torso harness suit (cutaway).

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torso harness suit, integrates the aircrew mem-ber’s parachute harness, lap belt assembly, andshoulder restraint harness. The parachute harnessis reeved through the torso suit to retain it in aposition to make it easier to put on and take off.The MA-2 suit provides optimum mobility to theaircrew member while restraining him to the seatduring emergency conditions; it serves as aparachute harness in case of aircraft ejection orbailout .

The MA-2 suit consists of a nylon webbingharness encased in nylon fabric, and is configuredinto a sleeveless, legless, torso garment availablein 16 sizes, extra small to extra-extra large long.Shoulder restraint adjustable straps with quick-release fittings provide attachment of theparachute riser assembly. A lap belt with a quick-release adapter is attached to the lap beltalignment webbing. The lap belt assemblyprovides attachment to a survival kit or parachuteand prevents damage to the abdominal areaduring parachute deployment. The suit is closedby a slide fastener with hooks and eyes foralignment. An adjustable chest strap provides thefinal necessary chest restraint adjustments. Thechest strap is secured by a friction adapter andhook and pile tape. A gated D-ring is attachedto the right shoulder adjustable strap near thequick-release fitting. The D-ring is for attachinga helicopter rescue hook.

The MA-2 (cutaway) is approved for use andis fabricated from an MA-2 by cutting awaynonstructural nylon cloth. This is done to improvecomfort in warmer climate operations and doesnot decrease either function or reliability of theassembly. The MA-2 (cutaway) is modified at thediscretion of the individual aircrew member.

The MA-2 is worn by aircrew members thatare fitted with a parachute designed for use withthe integrated system.

SIZING

The MA-2 restraint harness should fit theaircrew member properly to provide maximumprotection and comfort. The proper size harnessmust be identified and the fit of the selected sizemust be observed. Also, the fit must be made withthe aircrew member in the ejection seat to be surethat optimum restraint is provided. Finally, theaircrew member will be suspended in the harnessand the distribution of weight and body shift willbe looked at.

Select an initial harness size from the rangeof stock sizes by looking at the body build and

height of the aircrew member. A larger or smallersize harness is tried until the best fit is found.Aircrew members unable to be fitted with a stockharness should be considered for a custom-fitharness. Instructions for obtaining a custom-fitharness can be found in NAVAIR 13-1-6.2, andby contacting the Naval Weapons Center (NWC),China Lake, California. Consult the localphysiology unit to determine if a custom harnessis necessary.

FITTING

With the aid of a flight surgeon (if available)or naval aviation physiologist, you should proceedas follows:

1. Have the aircrew member put on the torsoharness. Ensure that the main sling saddle is underthe buttocks.

2. Check the location of the male Kochfittings. The optimum location of the male Kochis in the cavity/hollow below the clavicle (collarbone) when the aircrew member is standing orsitting.

3. Adjust the main sling webbing (it is thatportion of the main sling located between the legstrap and the chest strap), as shown in figure 4-14;it should be flush to the torso with no bulging orsurplus webbing evident. This condition shouldexist when standing, sitting, or in a hangingposition.

4. Ensure that the chest strap does not crossthe torso above the armpit when the aircrewmember is standing or suspended; it should notbe below the breast of the female aircrew member.

5. Inspect the diagonal back strap D-rings(fig. 4-14), and assure that they are positioned inthe same horizontal plane and equally spacedfrom the center of the back.

6. When the aircrew member has completedthe final adjustment of the harness, the cinchstraps are adjusted to a snug position.

With the aircrew member wearing his/her ownflight helmet, suspend him/her a few inches abovethe deck using a riser assembly with a 12-inchcross-connector strap. Inspect the chest strap,main sling, diagonal back strap adjustable links,and main sling saddle for proper position.Observe closely the aircrew member’s weightdistribution in the harness. The main sling saddle,when properly positioned, supports the bodyweight much like sitting in a swing. Weight stressis carried from the main sling saddle up through

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Figure 4-14.—MA-2 torso nomenclature.

the main sling to the canopy release fittings andriser assembly. Observe that when suspended, theaircrew member’s body has not shifted out of themain sling saddle.

LAP BELT AND SHOULDERADJUSTMENTS

To make the lap belt and shoulder harnessadjustments, the aircrew member must sit in anejection seat. Connect the lap belt fitting andadjust the lap belt until it is snug. Leave no slackin the lap belt. If the lap belt has been completelyadjusted to the stop and slack remains, try asmaller harness. If this does not work, the aircrew

member is considered a candidate for a custom-fit harness.

The canopy release/riser/shoulder restraintsystem must be connected. With the aircrewmember sitting upright, shoulders back, thereshould be no slack in the shoulder harnessrestraint. If the shoulder harness is fully retractedand there is slack, adjust the torso harness Kochfitting down until slack is removed.

Personnel whose prescribed torso harness doesnot meet the above criteria will be furtherevaluated in other size MA-2 harnesses, ifappropriate.

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INSPECTIONS

There are two inspections that are performedon the MA-2 torso harness—the preflight checkand the calendar or initial issue inspection. TheMA-2 preflight check is done before each flightand at intervals not to exceed 2 weeks. This checkis to be performed by the aircrew member. Theother inspection is a calendar or initial issueinspection. The MA-2 torso harness must beinspected upon initial issue and at intervalscoinciding with inspection of personal issueprotective equipment (i.e., life preserver, helmet,etc.). These inspections consist of the following:

NOTE: Before you perform any inspectionon the torso harness, you must determineif the harness is overaged. You would bewasting your time to perform an inspectionand then find out that the harness isn’t fitfor service because of being overaged.

1. Check the harness for its service life by firstchecking the date of its manufacture. This dateis located on the inside of the right front leg strap.The service/total life of the torso harness is 12years from when it was placed in service, or 15years from the date of manufacture, whicheveroccurs first. When an assembly reaches its servicelife limit, remove it from service and forward itto supply for disposition. If the torso harnesshasn’t reached 15 years from date of manufacture,you still have to check the service life. The datethe torso harness was placed into service isstenciled in the center of the lap belt strap on theouter surface. Whenever an in-service MA-2 lacksthe stenciled start of service date, its service lifeexpires 12 years from its date of manufacture.Now you are ready to perform a calendarinspection.

2. Check the chest strap friction adapter forcorrosion, distortion, cracks, presence of thelocking bar, sharp edges, and security of theattachment.

3. Inspect the shoulder canopy release fittingsfor corrosion, distortion, presence of the lockingbar, absence of sharp edges, proper routing of thewebbing, and security of the pin and lockingscrew. Ensure that the slot head screw is installedand the red lacquer tamper dot is intact.

4. Inspect the lap belt quick-release adapterfor corrosion, distortion, sharp edges, andsecurity of attachment.

5. Check the adjustable links located at therear inside of the suit for corrosion, distortion,

cracks, and sharp edges. Ensure that the cheststrap webbing is routed through these links.

6. Check the entrance slide fastener forcorrosion, missing teeth, presence of sliders (singleslider on the MA-2 cutaway modified), securityof attachment, and ease of operation.

7. Inspect the eyes and hooks at the entrancefor damage and security of attachment.

8. Inspect the gated D-ring or V-ring at theright shoulder for corrosion, distortion, cracks,and sharp edges.

9. Check the life preserver retention strap forcuts, rips, frayed or weakened webbing, securityof stitching, and presence and condition of snapfasteners.

10. Inspect the fabric panels for cuts, tears,fraying, deterioration, and security of stitching.

11. Inspect the harness webbing for cuts,tears, fraying, deterioration, and security ofstitching.

12. Repair any discrepancies and update theMA-2 configuration in accordance withprocedures outlined in NAVAIR 13-1-6.2.

General repair on the MA-2 consists ofreplacement of the hardware and repair of cloth.Do not replace any hardware that requiresrestitching of the harness webbing. Harnesses thatare damaged must be discarded.

For more detailed information concerningrepairs and modification to the MA-2 andcutaway modified torso harness suits, refer toNAVAIR 13-6-1.2.

HELMETS

The wearing of protective helmets while flyingin Navy aircraft depends upon the designation ofthe aircraft. You will find that aircraft such asfighters, attack planes, and helicopters usuallyrequire aircrew members to wear a protectivehelmet during takeoff, in flight, and landing.Other aircraft may require that the helmet be wornonly during takeoff and landing.

The Navy headgear for an aircrew member isconsidered to be a pilot’s protective equipment.Maintenance and upkeep is the responsibility ofthe Aircrew Survival Equipmentman.

There are a number of different types ofheadgear. Each has its own specific function. Asyou work with the different types, you’ll find thatwith very little effort, you can change their basic

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Figure 4-15.-HGU-33/P helmet assembly.

configuration to meet requirements for all fixed-wing aircraft.

The helmet assemblies in current use aredesignated as the HGU series. These lightweighthelmet assemblies are designed to provide face,eye, aural, and head protection when properlyassembled and fitted to the aircrew member. Thehelmet assemblies also house the headsetcommunications. Some helmet configurationsoffer specialized features such as VTAS (VisualTarget Acquisition System), laser protectivelenses, sonar operator binaural cables, and boommicrophones. This series of helmets is based onone type of helmet shell, the PRK 37/P.

MAJOR HELMET ASSEMBLIES

By taking the basic shell assembly, PRK-37/P,and adding different liners, visors, and com-munication systems (fig. 4-1 5), you can make 15different helmet configurations.

HGU-33/P HELMET ASSEMBLY. TheHGU-33/P is a single lens, form-fit helmet foruse in aircraft where an oxygen mask is usedexclusively.

HGU-34\P HELMET ASSEMBLY. TheHGU-34/P is a single lens, pad-fit helmet required

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for use in aircraft where an oxygen mask is usedexclusively. This helmet assembly is also aninterim backup for the HGU-33/P when a form-fit liner cannot be fabricated.

HGU-43/P HELMET ASSEMBLY. TheHGU-43/P is a dual lens, form-fit helmetincorporating a neodymium laser protective lensfor use in A-6 target range acquisition multisensory(TRAM) aircraft.

HGU-44/P HELMET ASSEMBLY. TheHGU-44/P is a dual lens, form-fit helmet usedin aircraft where an oxygen mask is usedexclusively.

HGU-45/P HELMET ASSEMBLY. TheHGU-45/P is a dual lens, form-fit helmet for usein OV-10A aircraft where an oxygen mask andboom microphone are both used.

HGU-45A/P HELMET ASSEMBLY. TheHGU-45A/P is a dual lens, form-fit helmetincorporating a neodymium laser protective lensfor use in the OV-10D aircraft where an oxygenmask and boom microphone are both used.

HGU-46/P HELMET ASSEMBLY. TheHGU-46/P is a form-fit helmet incorporating theVTAS (Visual Target Acquisition System) visorassembly for use in the F-4 VTAS aircraft.

HGU-47(V)l/P HELMET ASSEMBLY. TheHGU-47(V)l/P is a single lens, pad-fit helmetrequired in aircraft where a boom microphone isused or where a boom microphone and oxygenmask are used interchangeably.

HGU-47(V)2/P HELMET ASSEMBLY. TheHGU-47(V)2/P is a single lens, pad-fit helmetincorporating a boom microphone withoutamplifier and the CX-13155/A communicationcable for use in C-1A and C-2A aircraft.

HGU-47(V)3/P HELMET ASSEMBLY. TheHGU-47(V)3/P is a single lens, pad-fit helmetincorporating a boom microphone withoutamplifier and the CX-13164/A communicationcable for use in T-34 aircraft.

HGU-47(V)4/P HELMET ASSEMBLY. TheHGU-47(V)4/P is a single lens, pad-fit helmetincorporating a boom microphone withoutamplifier and the CX-4832A/AR communicationcable for use in P-3 aircraft.

HGU-49/P HELMET ASSEMBLY. TheHGU-49/P is a single lens, form-fit hel-met incorporating a boom microphone andCX-13128/A communication cable for use inS-3A aircraft.

HGU-50/P HELMET ASSEMBLY. TheHGU-50/P is a single lens, form-fit helmetincorporating a binaural headset required for usein the aft stations of the EA-3B aircraft.

HGU-52(V)1/P HELMET ASSEMBLY. TheHGU-52/P is a single lens, form-fit helmetincorporat ing a boom microphone andCX-13155/A communication cable for use in A-3aircraft.

HGU-52(V)2/P HELMET ASSEMBLY. TheHGU-52(V)2/P is a dual lens, form-fit helmetincorporat ing a boom microphone andCX-13155/A communication cable for use in E-2aircraft.

MAJOR HELMET COMPONENTS

The following helmet components are avail-able to achieve the desired configuration for theaircrew member helmet.

PRK-37/P HELMET SHELL ASSEMBLY.The PRK-37/P helmet shell assembly is intendedto protect the head during in-flight buffeting andemergency situations such as ejection, bailout, orcrash landings. It resists projectile penetration anddistributes impact forces over the entire head. Thehelmet shell is the platform for other componentssuch as the visor assembly, communicationdevices, and the oxygen mask.

PRU-39/P HELMET SHELL LINER AS-SEMBLY. The PRU-39/P is a helmet shell linerthat is a form-fit, foam-in place type assem-bly, which is installed in the PRK-37/P helmetshell assembly. The PRU-39/P consists of a rigidpolyurethane foam liner molded to fit the avia-tor’s head. The KMU-439/P (liner mold kit) ispositioned on the pilot’s head, and foam chemicalsare injected into it. The liner is finished with a softurethane foam comfort pad and leather covering.When properly fitted, the liner provides impactenergy absorption, helmet stability, and comfort.

PRU-39A/P HELMET SHELL LINERASSEMBLY. The PRU-39A/P is a helmet shell

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liner that is form-fit and constructed from one-ply fiberglass backing (contour-molded to fitwithin the PRK-37/P helmet shell), a leathercovering, and a comfort pad. The leather coveringand comfort pad are cemented to the fiberglassbacking. The fiberglass backing has two holes forintroduction of foam chemicals. When properlyfitted, the liner absorbs impact energy and makesthe helmet stable and comfortable. The aircrewmember wears a perspiration-absorbing cottonskull cap to extend the life of the liner.

PRK-40/P HELMET SHELL LINER AS-SEMBLY. The PRK-40/P helmet shell liner,which comes in two sizes and consists of apremolded 1/2-inch thick polystyrene foam liner,is molded to fit inside the PRK-37/P helmet shellassembly. Final fitting of the PRK-40/P isaccomplished by a series of different fitting pads.Also included in the assembly is a nape strap toallow a snugger fit. When properly fitted, the lineris designed to provide impact energy absorption,helmet stability, and comfort.

EEK-4A/P HELMET VISOR, SINGLELENS. The EEK-4A/P is a single lens helmetvisor assembly. When installed on the helmetshell, it protects the face and eyes from impact,projectile penetration, sun glare, dust, windblast,and fire. Each assembly comes with inter-changeable clear and neutral lenses.

PRU-36/P HELMET VISOR, DUAL LENS.The PRU-36/P is a dual lens helmet visorassembly, which provides the aircrew memberwith the same protection as the EEK-4A/P.

EEK-3/P HELMET VISOR, DUAL LENS.The EEK-3/P is a dual lens helmet visor assembly,which gives the aircrew member the sameprotection as the EEK-4A/P. Each assemblycomes with a neodymium laser protective innerlens and an interchangeable clear and neutralouter lens.

R-1825/AVG-8, R-1826/AVG-8 HELMETVISORS. The R-1825/AVG-8 mounts on a largesize helmet shell while model R-1826/AVG-8mounts on a medium. The receiver includes aparabolic visor, which provides the pilot witha collimated reticle image. Two sensor elec-tronic assemblies, one mounted in each sideof the receiver housing, assist in convert-ing the pilot’s line of sight into aircraftcoordinates. The main assemblies of the receiver

are the housing, the visor assembly, and theharness assembly.

COMMUNICATION CABLE ASSEM-BLIES. Each of the helmet assemblies is outfittedwith the appropriate communication componentsfor operation with aircraft ICS (Intercommunica-tion System).

M-87/AIC BOOM MICROPHONE AS-SEMBLY. The boom microphone assemblyprovides communication when the oxygen maskis not in use, as well as walkaround capabilities.

NOTE: Detailed information on thefabrication of the form-fit liners can befound in the NAVAIR 13-1-6.7.

SIZING THE PRK-37/P

When building up the HGU pilots protectivehelmet, it is very important that you start withthe proper size helmet shell (PRK-37/P). ThePRK-37/P is available in four sizes, (medium,medium/large, large, X-large). To determine theproper size, you must first measure thecircumference of the head, at the hatband line,with a tape measure. Once you have the correctmeasurement, you can determine the equivalenthelmet size by referring to table 4-3.

HELMET CONFIGURATION BUILDUP

Once the basic PRK-37/P helmet shell andmajor components are received, carefully inspectthe shipping containers for evidence of damageor signs of abuse. Open each container and verifythat all the required items have been included. Ifany parts are defective, damaged, or missing,replace all items in the shipping container, preparea Deficiency Investigation Report, and notify theproper authority. Once the helmet shell andrelated components have been accepted, the shellmay be built up by adding or removing majorcomponents in order to obtain the desiredconfiguration for required aircrew or aircraftapplication. Before you attempt to build up thehelmet, it is necessary to follow the steps outlinedin the NAVAIR 13-1-6.7 for each majorcomponent you are installing.

MAINTENANCE

As with all equipment that you work with andmaintain, proper care of the fixed-wing series

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Table 4-3.—PRK-37/P Helmet Shell Sizing Guide

helmet assemblies is essential to ensure optimum soiled or slightly scratched. clean the outside visorperformance during emergencies and routineflights. The aircrew member is responsible forcleaning and proper handling of the helmet. Allrepairs and modifications are done by the PR atthe organizational maintenance level or above.

Cleaning

You must clean all parts of the helmet at leastevery 90 days. To clean the shell and edge roll,use mild detergent and water. Sometimes you mayhave to use a mild abrasive scouring powder toremove stains or scuff marks. The chin strap, napestrap, and fitting pads may be cleaned by lightlysponging with a solution of detergent and water.The skull cap may be laundered in a machine, butthis is the responsibility y of the aircrew member.

The visor assemblies are probably the mostimportant parts that require cleaning. If you haveever worn sunglasses and they became dirt y, youknow how aggravating that can become. By usinga solution of mild soap and water and a soft cloth,you can clean most visor’s lenses. Rinse off thesolution and allow to dry. If lenses are still

only with liquid canopy polish. The inside of thevisor must be cleaned with a soft, lint-free cloth.After cleaning, apply an antifog solution.

Addition of Reflective Tape

The addition of reflective tape on the helmetprovides for improved detectability of the downedaircrew member. The tape must be affixed to allhelmets. However, in combat areas the tape maybe removed, as the crew commander directs.White and red reflective tapes are recommended,as they afford the greatest detectability y. Whenapplying the tape, you use any pattern specifiedby the unit commander, as long as the tape patterncovers a minimum of 100 percent of the helmetvisor housing and outer shell.

To apply the tape, you should preheat boththe helmet and the tape to approximately 100 “F.This improves the adherence qualities and ease ofapplication.

Aviator helmets should be taped in accordancewith the provisions of chapter 7 of OPNAVINST3710.7 (series) (general NATOPS) and any typecommander directives.

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INSPECTIONS Visual Inspection

There is one basic inspection that you mustperform on the helmet—the calendar inspection.In addition, the aircrew member is responsible fora preflight/postflight inspection before and aftereach flight.

Calendar Inspection

The calendar inspection is conducted byorganizational-level activities upon issue and every90 days thereafter. The 90-day inspection consistsof a visual inspection, functional check, and athorough cleaning.

NOTE: Every other calendar inspection,or every 180 days, the chin strap, napestrap pad, ear seals, and skull cap must be

To visually inspect the helmet, you must makea thorough sight inspection for broken parts,security of attached parts, loose or brokenstitchings, and also inspect the earcups for soundattenuation and pliability.

Functional Check

The functional check is performed with the aidof a REDAR oxygen hose test set. If this unit isnot available, standard shop procedures shouldbe performed. Refer to NAVAIR 17-15BC-7 forthe proper testing sequence.

SPH-3C HELMET

The SPH-3C helmet, shown in figure 4-16, isdesignated for use by all helicopter aircrew

replaced. members.

Figure 4-16.—SPH-3c protective helmet.

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The SPH-3C helmet protects the wearer’s headduring in-flight buffeting or crash landings. It isdesigned to distribute impact forces over the entirehead, and to absorb these forces so that a mini-mum amount of impact reaches the wearer’s head.The SPH-3C helmet is supplied in two sizes, regu-lar and extra large. The helmet consists of an outershell assembly, an inner foam liner, sizing liner,inner cloth liner assembly, dual integrated visor,communication cord set, and a microphoneadapter.

The outer shell assembly is fabricated fromKevlar and polyester resin, and it provides impactand penetration protection. An edge roll, madeof neoprene foam, provides protection from thehelmet edges.

The inner foam liner is made of cellularpolystyrene sheets molded to fit the inside contourof the outer shell. The liner is provided to absorband dissipate impact forces.

The sizing liner, which is optional, aids infitting the helmet to the aircrew member’s headcontour by padding the helmet at the nape of theneck.

Sizing liners are provided in 1/4-, 1/2-, and5/8-inch sizes.

The inner cloth liner assembly includes thesonic earcup assemblies and foam pads for sizingand comfort; it also has adjustable crown andnape straps.

The dual integrated visor provides protectionfrom sun glare, dust, windblast, foreign particles,and flash fires. The visors are protected by amolded fiberglass housing when not in use. Twovisors, clear and neutral, are available. Thepercentage of visible light transmittance of theneutral visor is 8 to 16 percent. The percentageof light transmittance of the clear visor is 87percent or greater.

The communications cord set connects theaircraft communications system to the helmetearphones. The microphone adapter, located onthe helmet, allows attachment of a boom-typemicrophone.

Fitting

The SPH-3C protective helmet must beindividually fitted to the aircrew member. Formaximum protection, comfort, and soundattenuation, a good fit is a snug fit at the cheeks,forehead, and nape of the neck. A loose fittinghelmet is more apt to produce pressure areas anddiscomfort.

If the helmet moves independently of the head,readjust the sizing liners, spacers, and adjustingstraps. If necessary, file and sand the nose

indentation to fit the contour of the aircrewmember’s nose. Ensure that the visor at the noseindentation is free of nicks and roughness.

Maintenance Procedures

Minimal maintenance, which is cleaning thevisor and outer shell, can be performed by the air-crew member as needed. All other maintenanceoperations must be performed upon issue and atleast every 90 days thereafter by qualified person-nel at the lowest level of maintenance possible.

Inspect the sizing liners and inner foam linerfor looseness, re-cement where applicable, and re-place worn or torn sizing liners. Inspect the shellassembly for cracks, dents, scratches, splits, anddelamination. Inspect all hardware for damageand security of attachment, tighten or replacehardware as necessary. Inspect straps, communi-cations cord set, earphones, and dual visor as-sembly for damage. Replace parts as necessary.

The visor may be cleaned with mild soap andwater and dried with a soft, clean cloth. Toremove minor scratches or remaining soiled areas,use acrylic plastic polish.

To preserve the visor’s plastic surface, usepolishing wax for the final application. Do notuse solvent or abrasive-type cleaners.

OXYGEN MASKS

The oxygen mask is the final link in conveyingoxygen from the aircraft system to the user. A

- satisfactory regulator and oxygen system or a fullcylinder’ of oxygen is of little value to a pilot ifhis oxygen mask is not operating properly in everyrespect.

The oxygen mask is the pilot’s personalequipment; that is, after initial fitting, they areretained by the individual. Fitting, adjustments,maintenance, cleaning, and incorporatingmodifications are the responsibility of the PR.

The important factor to remember aboutidentifying any oxygen mask is its compatibilitywith the oxygen system with which the mask isto be mated.

PRESSURE-DEMAND OXYGENMASK MBU-12/P

Oxygen mask assemblies are designed to beworn over the face, forming a seal to the cheeksover the bridge of the nose and under the chin.The mask is designed for use with a regulator,which provides breathing gas (100-percent oxygenor oxygen diluted with air) upon demand at apressure schedule dependent on the altitude. Themask can also be used with continuous-flow

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bailout or walkaround oxygen sources. The maskalso provides facial protection from projectilesand fire, as well as working at depths of 16 feetunderwater. A properly fitted oxygen mask is alsoessential to helmet retention in high-speedejections. The facepiece permits utilization of thevalsalva maneuver to clear clogged sinuses byholding your nose with your mouth shut andtrying to exhale. Then open your mouth wider.This operation will clear most sinus cloggings.

The MBU-12/P pressure-demand 02 mask isthe basic mask used to configure any of thefollowing oxygen mask assemblies:

MBU-14(V)1/P MBU 16/PMBU-14(V)3/P MBU 17(V) 1/P

MBU 15/P MBU 17(V)2/PInformation on each assembly can be found

in NAVAIR 13-1-6.7. Figure 4-17 shows aMBU 12/P configured into a MBU 14(V) 1/P.

Figure 4-17.—MBU-14(V)1/P oxygen mask assembly.

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Figure 4-18.—Cross-sectional view of a combination inhalation/exhalation valve.

The MBU-12/P oxygen mask subassembly isa lightweight, low profile, pressure-demand typeof oxygen mask. The mask features an integralfacepiece/hard shell. The facepiece is of pliablesilicone and the hard shell is of polysulphonate.The mask also features a combination in-halation/exhalation valve, a flexible, soft siliconehose, and an MS27796 connector. The mask isfitted with an antistretch cord, which is se-cured at the upper end to the valve and at thelower end to the MS27796 connector. The hardshell is outfitted with a microphone receptacleassembly on the outside and a microphone bracketon the inside for positioning the noise cancelingmicrophone.

Combination Inhalation/Exhalation Valve

The valve offers the advantage of miniaturesize, but it does exhibit slightly higher exhalationresistance. The valve is sensitive to both dust andcontamination. As a PR, you are responsible forcleaning the mask.

Operation of the valve is very simple.The valve is installed in the mask hard

shell in such a way that one side of thevalve “sees” mask pressure and the otherside “sees” hose pressure (fig. 4-18). Uponinhalation, the pressure within the mask be-comes less than the pressure within the oxygenhose; the flapper of the valve opens andoxygen from the hose enters the oxygen mask(fig. 4-19). Upon exhalation, the pressure withinthe mask becomes greater than the pressure withinthe hose; the flapper closes; the spring/diaphragmcollapses; and the exhalation is exhausted (fig.4-20).

Sizing

To operate properly, the MBU-12/P oxygenmask must be the correct size for the aircrewmember. The concept of sizing as used hererefers to the basic methods to be followed bythe Aircrew Survival Equipmentman for re-quisitioning the proper size oxygen mask as-sembly from supply. Once the basic oxygen masksize has been determined and requisitioned, theMBU-12/P oxygen mask is ready for buildup tothe ultimate configuration desired. To select theproper size, use the caliper shown in figure

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Figure 4-19.—Cross-sectiona1 view of valve during inhalation.

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Figure 4-20.–Cross-sectional view of valve during exhalation.

Figure 4-21.—Measuring for proper size of O2 mask.

4-21; measure the distance from the tip of thebottom surface of the chin to the point ofmaximum depression of the nasal root (smallestpart of the upper end of the nose). Once the basicsize has been determined, requisition a new maskthrough normal supply channels.

ATTACHMENT OF BAYONETAND RECEIVER MECHANISM

Before you fit the mask to the helmet, youshould check to see if the MBU-12/P has beenconfigured to the correct assembly. For completeinformation on configuration buildup, refer tochapter 13 of NAVAIR 13-1-6.7. Once you havea complete assembly of the right size, you’re readyto fit the mask to the helmet.

The mask has four mask retaining straps. Youshould thread the straps through the slots in theoffset bayonet fittings, as shown in figure 4-22.Then insert each offset bayonet fitting into areceiver mechanism to the second locking posi-tion. When the bayonet is inserted in the receiver,the first click is caused by the entry of the bayonetinto the entrance of the receiver housing, but itis not a locking position. There are normally threeclicks when inserting the bayonet to the secondlocking position of the receiver. When the bayonetis in the second locking position, the end of thebayonet will be approximately even with the outer

Figure 4-22.—Mask retaining straps.

edge of the exit slot on the back of the receiver.This proper positioning of the bayonet end canbe checked either visually or by passing a fingerover the exit slot on the back of the receiver.

Have the aircrew member place the helmet onhis head and hold the oxygen mask in properposition on his face.

Inspect each receiver mechanism assembly tobe sure that the rotating feature of the device islocked in its central position. If the rotatingfeature is found not to be centered, loosen the twolocking screws on the nameplate of the receiver.Adjust the receiver until the bayonet is at rightangles to the receiver. Retighten the locking screws(fig. 4-23).

The receiver has a rotating feature that allowsa 15-degree angle of freedom so that the receivercan be adjusted slightly in either direction if thisbecomes necessary after attachment to the helmet.Place the receiver on the helmet so that the upperand lower straps have equal tension. The receivershould be positioned as close to the edgeroll aspossible to minimize bayonet/edgerollinterference.

With a grease pencil, trace around eachreceiver to mark its outline on the helmet (fig.4-24). You should use this outline to align thereceiver on the helmet. Now remove the helmetfrom the wearer and using the back plate of thereceiver as a template, mark the locations for thefour receiver mounting holes on the helmet (fig.4-25). Remove the earcup assemblies and drill fourmounting holes in the helmet. Do this on each sideby using a No. 25 (0.1495-inch diameter) drill. It

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Figure 4-23.—Adjusting receiver assembly.

Figure 4-24.—Marking helmet.

Figure 4-25.-Marking holes.

is necessary to peel back the pile fastener tapeinside the helmet to allow the attachment of thebayonet receivers. Attach the receiver mechanismassemblies to the helmet with the backup plateinside the helmet. Note that the forward receiverholes nearest the edge of the helmet need longerscrews. At this time you can replace the pilefastener tape and replace the earcup assemblies.It maybe necessary to use adhesive when replacingthe pile tape.

Fitting

The concept of fitting as used here refers toprocedures required for necessary componentadjustment following oxygen mask assemblybuildup. Fitting instructions are provided only asa general guide. Because of the wide variation infacial shapes likely to be encountered, it is notpossible to present detailed guidance. A successfulfit depends largely on the skill and experience ofthe Aircrew Survival Equipmentman in selectingand adjusting the oxygen mask assembly to theaircrew member’s face. Improperly fitted oxygenmasks do not provide a positive face seal forpressure breathing and do not protect the aircrewmember in emergency situations.

Have the aircrew member don the helmet, andensure that the helmet nape strap has beenadjusted to a snug fit. Insert each bayonet into

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the second locking position of the receiver and NOTE: If leaks occur between faceformadjust the straps until the mash is snug and and face, check to see if proper mask sizecomfortable. Attach the straps in place with two has been issued. If leakage still occurs,turns of “E” thread. Perform a functional check adjust helmet bayonet receivers. Refer toon the oxygen mask. table 4-4 for troubleshooting procedures.

Table 4-4.-Troubleshooting

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Figure 4-26.—Adjustment of bayonet receivers.

Adjustment of Bayonet Receivers

To adjust the bayonet receivers, loosen the twoadjusting screws (fig. 4-26) and rotate the receiversuntil the mask fits properly. Retighten theadjusting screws.

NOTE: Ensure that the top buckles aretacked down prior to any adjustment.

Adjustment of the bayonet receivers isperformed with the helmet assembly and oxygenmask assembly donned by the aircrew member.

When properly fitted, the MBU-12/P oxygenmask can retain a pressure in excess of ambientpressure up to the maximum pressure supplied bythe regulator.

Maintenance

Proper care and use of oxygen masks isessential to ensure optimum performance duringroutine flight operations and emergencies. Theaircrew member’s responsibility for maintenanceof the oxygen mask is limited to cleaning. Repairsor other maintenance actions required areperformed at the organizational level or above.

PREFLIGHT/POSTFLIGHTINSPECTION

The preflight/postflight inspection is a visualinspection performed by the aircrew member to

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whom the oxygen mask is issued before eachflight. The preflight/postflight inspection consistsof-the following-procedures:

NOTE: Defects or questionable areasnoted during this inspection must bereferred to the proper maintenance activityfor required corrective action.

1. Check the communication system andmicrophone for proper installation.

2. Check the mask for damage and properoperation by using the tester and/or aircraftoxygen and communications system.

Calendar Inspection

The calendar inspection is conducted every 30days at the organizational level and consists ofa visual inspection, a functional check, and athorough cleaning of the oxygen mask assembly.Refer to NAVAIR 13-1-6.7 for visual inspectionand functional check procedures.

NOTE: If a discrepancy is noted, refer totable 4-4 for guidance.

Cleaning Mask

To clean and sanitize the oxygen maskfacepiece and housing assembly, proceed asfollows:

Preferred solution. Make a 1 percent by weightsolution of cleaning compound (Detergent, Gen-eral Purpose, MIL-D-1 6791, Type I) by adding1/4 to 1/2 ounce (liquid) of the compound to 1gallon of water.

CAUTION

WHEN THE FOLLOWING ALTER-NATE CLEANING SOLUTION MUSTBE USED, ONLY THE LATHER FROMTHE SOLUTION IS USED FORCLEANING. THIS PREVENTS UN-DISSOLVED SOAP SOLUTION FROMGETTING INTO THE VALVE.

Alternate solution. Make a suitable soapsolution by adding approximately 4 tablespoonsof soap powder (P-S-600) to 1 gallon of water.Hardness of water may require more soap, butthe solution must be sufficiently strong to readilyform lather when agitated. Make sure that all soapparticles are dissolved.

CAUTION

ENSURE THAT CLEANING SOLU-TION DOES NOT ENTER THE IN-HALATION/EXHALATION VALVEASSEMBLY.

Moisten a gauze pad with the cleaning solutionand wash the facepiece and housing assembly bothinternally and externally.

After washing, the mask should be thoroughlyand repeatedly rinsed with warm water.

NOTE: Another alternate sanitizer,Aerosol Antiseptic Spray SBT-12 (di-bromosalicyl bromanicide), manufacturedby Lever Brothers, Inc., can be used.Directions for use are indicated on thecontainer.

After all parts are dry, disinfect by using agauze pad or other lint-free wipers, with a solutionof 2 tablespoons of chlorine bleach per gallon ofwater; rinse with clear water and air dry. Becertain disinfectant reaches inner crevices of thefaceform.

To clean the delivery hose, wash it with acleaning solution and rinse it with clear water.Allow all parts to air dry.

When cleaning the inhalation/exhalation valveassembly, it will be necessary for you to obtaina container just large enough to partially submergethe valve. Fill the container half full ofbenzalkonium chloride solution, MIL-B-37451, ora solution of 70 percent isopropyl alcohol and 30percent distilled water.

239.423Figure 4-27.—Removing locking nut.

By using a valve wrench, as shown in figure4-27, unscrew the valve nut and remove thelocking nut, bearing washer, and isolation washerfrom the inside of the mask. This will allow thevalve, sealing washer, delivery tube, andconnector assembly to be removed as a unit fromthe outside of the mask. Hold the base portionof the valve and submerge the operating portionof the valve into the solution. Normally, only afew seconds are required to remove any stains andresidue. For stubborn residues, use a cotton swabsaturated with benzalkonium chloride and rublightly to remove. Gently shake excess solutionfrom oxygen valve and allow it to air drycompletely.

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CHAPTER 5

RESCUE AND SURVIVAL EQUIPMENT

Learning Objective: Upon completion of this chapter, you will be able torecognize, inspect, and maintain survival items and rescue equipment.

When an aircrewman has to leave his aircraftin a hostile environment, survival items providea means of sustaining life, attracting the attentionof rescuers, and aid in evading the enemy.Survival items may be packed in life rafts,droppable kits, and kits intended to be carried orworn by the aircrewman.

As an Aircrew Survival Equipmentman, yourresponsibility to the aircrewman is to maintainthese survival items. You need to know how theywork and be able to pass that information on tothe aircrewman.

Many of the items that are frequently carriedby the aircrewman are discussed in the followingtext. The ones that are not covered in this chapterare described in the NAVAIR 13-1-6.5 manual.

SIGNALING EQUIPMENT AND DEVICES

The following items are used to attract theattention of a rescue team. With the properknowledge, ability, and caution, these items canprovide invaluable assistance in a survivalsituation.

DYE MARKER

The dye marker (fig. 5-1) is an aniline dyepowder in a sealed container. When placed in thewater, it produces a bright color that appearsorange or fluorescent green-depending on howthe light strikes it. It is used to attract the attentionof rescue aircraft. The dye is exhausted from thepackage in 20 to 30 minutes and ceases to be agood target after 1 hour. The dye-exposed water

239.399Figure 5-1.—Dye marker.

area is visible at an approximate distance of 10miles from an altitude of 3,000 feet. If rapiddispersion of the dye is desired, agitate the packetof dye vigorously in the water.

SIGNALING MIRROR

The emergency signaling mirror is approxi-mately 3 by 5 inches and consists of an aluminizedreflecting glass mirror, a back cover glass, anda sighting device. It is used by personnel in raftsor on land to attract the attention of passingaircraft or ships by reflection, either in sunlightor in hazy weather. The reflections of thisshatterproof mirror can be seen at a distance 3to 5 times as great as those from which a raft canbe sighted at sea. On a clear sunny day, the mirror

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239.340Figure 5-2.—Operation of the signaling mirror.

reflects the equivalent of 8 million candlepower.Flashes from the mirror have been seen from adistance of 40 miles. A smaller mirror, measuring2 by 3 inches, is also used in some kits.

Figure 5-2 shows the operation of the signalingmirror. Past experience indicates that personnelmay have difficulty using the mirror in a bobbingraft at sea. Signaling practice with the mirrorshould be encouraged as part of the trainingprogram for flight crews. Such practice reducesthe difficulty in case of emergencies. Before usingthe mirror, read the instructions printed on itsback.

MK 79, MOD 0 ILLUMINATIONSIGNAL KIT

The Mk 79 signal kit is supplied with onepencil-type launcher (Mk 31), seven Mk 80 screw-in cartridges, and a bandolier for storing the flaresuntil use. Protective caps should be used over theprimers of the cartridges when not using thebandolier.

239.400Figure 5-3.—Mk 79 Mod 0 illumination signal kit.

Each cartridge flare has a minimum durationof 4 1/2 seconds and can be launched up to 250feet. When the launcher is stored in the survivalvest, it should be in the COCKED position andempty (fig. 5-3). Refer to NAVAIRproper handling and storage of the

MK 13, MOD 0 SIGNAL FLARE

The Mk 13, Mod 0 signal flare isattract the attention of SAR aircraft

11-15-7 forsignal kit.

intended toand to give

them drift direction. To avoid being burned bysparks, the ignited Mk 13, Mod 0 signal must beheld at arms length and no more than shoulderhigh. If the Mk 13, Mod 0 signal is being usedat sea, hold it over the side of the life raft toprevent damage to the life raft from hot residue.The Mk 13, Mod 0 signal may be put out bydousing in water or snuffing in sand. Refer toNAVAIR 11-15-7 for precautions, handling, andstorage procedures.

The Mk 13, Mod 0 consists of a metal cylinderclosed at each end. There is a tear friction tapeigniter on a clip at each end. One end containsa red flare for nighttime use; the opposite endhouses an orange smoke signal for daytime use.Each end of the signal burns approximately 20seconds. The nighttime end of the flare hasprotrusions that you can feel in the dark. On theoutside of the Mk 13, Mod 0 flare are operatinginstructions and a lot number (fig. 5-4). The lotnumber should be checked each time the flare isinspected to ensure that the flare is stillserviceable. A list of lot numbers that are notserviceable can be found in current aircrew

5-2

239.401Figure 5-4.—Mk 13 Mod 0 marine smoke and illumination

signal.

equipment bulletins. Any flares manufacturedbefore 1960 should also be removed from service.

DISTRESS LIGHT (SDU-5/E)

The SDU-5/E light equips aircrew membersand shipboard personnel with a high-intensityvisual distress signal. The infrared filter and blueflash guard, contained in the SRU-31/P survivalkit, are used in conjunction with the SDU-5/Elight for signaling purposes in combat areas.

The SDU-5/E is commonly called a strobelight. It emits a high-intensity flashing light. Thislight is visible for great distances at night.

The SDU-5/E strobe light requires aninspection by the PR each time the aircrewman’sflight gear is inspected (every 90 days). Theaircrewman should perform a daily inspection toensure that the light is operative. The calendarinspection consists of activating the light for 2minutes. If the light does not operate at 50 flashesper minute (plus or minus 10 flashes) for the2-minute duration, replace the battery. Repeat theprocedure; if the light still does not operate,remove the light from service.

You must perform this test both in totaldarkness and also in a lighted area. Some lightsoperate in a lighted area but do not operate inTOTAL darkness.

You should store the batteries for theSDU-5/E light in a cold area (refrigerator) toprolong their service life and dependability.

To avoid causing possible night blindness tothe crewman by accidental activation, install theSDU-5/E light in the SV-2 survival vest with thedome down and a protective cap installed overthe switch.

INDIVIDUAL AIRCREWMAN’SSURVIVAL KIT (SRU-31/P)

The complete SRU-31/P kit consists of twoparts; the first packet contains medical items that

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an aircrewman might need in an emergencysituation. The local medical department hasresponsibility for the medical items that arecontained in packet number one.

Packet number two contains general survivalitems. They are also intended to be used only inan emergency situation.

Packet one and packet two are contained ina carrying bag. Each packet can be replacedindividually. Each item within a packet is packedin a transparent bag, which is hermetically sealedand retained in place by means of hook-and-piletape. Additional adhesive-backed discs of hook-and-pile tape are contained in the spare pocketof each container.

MEDICAL PACKET

The following items are contained in themedical packet of the SRU-31/P kit:

Soap . Nonperfumed, intended to avoiddetection.

Instruction card. Provides general condensedinstructions on use of survival items.

Antidiarrhea tablets. Dosage rates listedon instruction card. Expiration 4 years.

Pain killer (aspirin). Expiration date listedon foil packet. Replace as required. Dosage ratelisted on instruction card.

Band-Aids.

itsSurgical tape. Ensure the package is intact andsterile seal is not damaged.

Eye ointment. Expiration date of 5 years.

Water purification tablets. Manufacturer’sdate and applicable instructions listed on bottle.

Bandage (elastic). Ensure package is intact andsterile seal is not damaged.

Insect repellent.

GENERAL PACKET

The following items are contained in theGeneral Packet of the SRU-3/P kit:

Metal matches. These may cause spontaneousignition through oxidation. The match shouldremain in its original sealed container (foilwrapped) until ready for use. All metal matchesin polyethylene and open packets must beremoved from service and discarded in a fireproofcontainer.

Mirror. This is the signaling mirror describedat the beginning of this chapter.

Water bag. One-quart capacity. Belt loopsprovided for convenient carrying.

Signal panel. Silver/orange paulin, imprintedwith the ground-to-air emergency code. It alsomay be used as a blanket for protection againstunfavorable weather.

Mosquito headnet and mittens. Provided forprotection against insect bites.

Chiclets. Multi-flavored gum, designed torelieve tension.

Multiflavored candy. Service shelf life isindefinite.

Flash guards. The flash guards are used inconjunction with the SDU-5/E light as a signaldevice during rescue operations. The flash guardsare blue or red in color.

The packet also contains surgical tape, a waterreceptacle, wrist compass, razor knife, tweezers,and pins.

INSPECTION

You should inspect all the items in theSRU-31/P survival kit during periodic equipmentinspections and replace them as necessary.

RATIONS

The rations carried by aircrew personnel arenot intended for subsistence but as a source ofquick energy when no other food is available.

The food packet contains two packets ofcandy and gum, twine, and an instruction sheet.

5-4

239.402Figure 5-5.—Rations.

When you inspect any item that contains theserations, you should remove and replace any foodpacket that is older than 6 1/2 years (fig. 5-5).

CANNED DRINKING WATER

Canned drinking water (fig. 5-6) is intendedfor use in emergencies when no other clean water

Figure 5-6.—Canned drinking water.239.403

is available. One can of water supports a survivorfor about 1 day.

A can of drinking water contains 10 ouncesof pure drinking water and maybe carried in thisready-to-use state.

The canned drinking water should be inspectedupon issue and every 90 days thereafter, or atintervals to coincide with the inspection scheduleof the kit or assembly in which the can is stored.Inspection will consist of the slap test and the shelflife and service life check.

The slap test consists of slapping the can ofwater against the palm of your hand and listeningfor a sharp metallic click. This noise is caused bythe absence of air to cushion the impact of thewater against the can. If this distinct noise is notheard, then air has leaked into the can and itshould be replaced.

The shelf life and the service life of cannedwater are both indefinite as long as the cans passthe slap test and there are no signs of exteriordeterioration.

239.437Figure 5-7.—AN/PRC-63 radio set.

SURVIVAL RADIOS AND BEACONS

Today’s rescue procedures are based uponearly detection and fast recovery of the survivingaircrewman. Once an aircrewman has been placedinto a survival position, it is essential that he belocated as soon as possible. The one item that canaccomplish this is the survival radio.

Navy aircrewmen carry, as part of theirpersonal survival equipment, a two-way com-munication radio. This radio is either theAN/PRC-63 or the AN/PRC-90. You must checkeach aircrewman’s radio when you perform the90-day calendar inspection on his survivalequipment.

This chapter describes the operation andinspection of these radios. It also covers theAN/URT-33A and the AN/PRT-5 radio trans-mitters.

AN/PRC-63 RADIO SET

The AN/PRC-63 radio set is a compact,rugged, lightweight, battery-powered, micro-electronic transceiver. (See figure 5-7.) Theradio set has three basic modes of operation:

1. beacon tone transmission (activated eithermanually or by means of an automatic deploy-ment device);

2. voice transmission; and

3. voice reception.

Simplicity of operation has been the keynotein the design of the AN/PRC-63 radio set. A slideswitch turns the radio set on (in beacon mode)or off, and a three-position toggle switch changesfrom beacon transmit to either voice transmit orvoice receive. A volume control, located in theupper corner of the radio set, controls the levelof sound output of the beacon confidence tone(used to verify that the beacon signal is gettingout) and the receiver. No other controls have beenprovided or are required. All these controls canbe operated with either hand (bare or gloved). Ifthe user loses consciousness and releases the radioset (once turned on), it automatically returns tothe beacon mode of operation.

General Principles of Operation

The AN/PRC-63 radio set provides two-wayvoice communication with a searching aircraftthat is equipped with compatible transmitting andreceiving equipment within a range of 25 milesand an altitude of 10,000 feet. A search aircraftflying at 10,000 feet and equipped with compatibledirection-finding equipment can locate anAN/PRC-63 radio set transmitting in the beaconmode at a distance of approximately 70 miles

5-5

(line of sight) between the search aircraft and theradio set.

The AN/PRC-63 radio set can be worn as partof the aircrewman’s flight clothing or life jacket;it is secured to the garment by a strap attachedto the slots in the battery housing. The automaticdeployment device supplied with the radio set,when suitably connected to the parachute harnessof the aircrewman by the user, will allowautomatic transmission of the beacon tone uponparachute deployment. The radio can also bepacked in a seat pack and, with the samedeployment device suitably connected, can beautomatically placed in beacon tone transmissionmode upon ejection from the aircraft. The lanyardattached to the deployment device has beendesigned to withstand a pull force of 20 poundswithout breaking.

The downed aircrewman may remove theradio set from his flight clothing, life jacket, orsurvival kit and change its mode of operation toeither voice transmit or voice receive by pressingthe appropriate end of the rocking toggle actuator.In the event that he becomes injured, disabled,or otherwise incapable of selecting the desiredmode of operation, the radio set will continue totransmit MCW beacon signals until the batterypower is exhausted.

Function and Use of Operating Controls

The function and use of the operating controlsare described in table 5-1.

NOTE: When POWER ON/OFF actuatoris in OFF position or in ON position withthe deployment device installed, all otheroperating controls are disabled.

The radio set can be held in either hand andoperated by the thumb or fingers, respectively.In the normal operating position, the speaker/mike faces the operator.

NOTE: During operation, the radio setmust be held in the upright position(antenna vertical), or loss of transmissionor reception will result. For best results,hold the radio set approximately 1 to 2inches from the mouth when speaking, orear when listening.

In the receive mode the sound is con-trolled by the volume control knob, whichis located in the upper corner of the radioset (opposite the flexible whip antenna) andmarked VOLUME MAX. Full clockwise rota-tion gives maximum volume; full counter-clockwise rotation gives minimum volume. Thesound of the beacon monitoring tone is alsocontrolled by this knob.

NOTE: Neither the beacon nor voice-transmitter output is affected by theposition of the volume control knob.

Table 5-1.—Operating Controls and Functions

Control Function

POWER OFF Radio set is in storage condition.

POWER ON Radio set is in beacon mode of operation.

POWER ON Radio set is in standby condition ready forDeployment device installed automatic activation.

POWER ON Radio set is in receive mode.RECEIVE VOICEPRESS AND HOLD

POWER ON Radio set is in transmit mode.TRANSMIT VOICEPRESS AND HOLD

A

5-6

Inspections

There are three inspections/test intervals pre-scribed for this type of radio. (They are alsoprescribed for the AN/PRC-90.) The first daily/preflight is performed at the squadron level by theaircrewrnan. It is to be performed daily or prior toeach flight. It consists of a basic operational checkusing an AN/PRM-32 radio tester or with the aid ofa known good radio. Prior to testing the emergencyradio, you should call flight operations to informthem that you are going to test a radio.

Every 90 days the radio must be inspected bythe PR at the organizational level. It is best tomake this inspection in conjunction with theinspection performed on the aircrewmen’spersonal survival equipment.

The last of the three inspections is performedat the intermediate level (AIMD). This inspectionis performed every 180 days by personnel in theavionics rating.

The testing procedures for all three inspectionsare outlined in NAVAIR 16-30PRC 90-2 for the

Battery Replacement

The Mallory battery will require frequentinspections to ensure that it hasn’t lost any of itsoperating life. When operating in a high-temperature area, the inspection should beconducted at least every 30 days. The service andshelf life of the battery expires 36 months fromthe date of manufacture. When the battery failsto produce the power for the radio to operate atmaximum operating range, you must replace it.Any battery that shows evidence of a swelling,chipped, or cracked surface, or moisture must becondemned and a new battery installed.

AN/PRC-90 RADIO SET

The AN/PRC-90 (fig. 5-8) radio set is a dualchannel, battery-powered, personal emergencyrescue device used principally for two-day voiceor MCW (modulated continuous wave, which isused to send Morse code signals) communicationsbetween a downed aircrewman and a rescue air-craft. The radio transmits either voice. toneAN/PRC-90 radio and in

63-1 for the AN/PRC-63.NAVAIR 16-30PRC

(MCW), or swept-frequency homing beacon

239.438Figure 5-8.—AN/PRC-90 controls and indicators.

5-7

signals to guide rescue aircraft to the downedaircrewman. Although the PRC-90 is a line-of-sight communications device, it has a voice rangeunder ideal conditions of 60 nautical miles toaircraft operating at 10,000 feet. The automaticdirection finder has a range of 50 nautical milesand atone (code signal) range of 80 nautical milesto aircraft operating at an altitude of 10,000 feet.

Batteries

The batteries are tested by using Test Set TS2530/UR. Batteries are considered to have amaximum shelf life of 36 months from the dateof manufacture. This shelf life is based upon a

storage temperature of 70 ‘F. If the temperatureincreases, their storage life is shortened. Forexample, if the temperature reaches 130 ‘F, thestorage life can be reduced to as short as 1 month.When you are in an activity that uses this battery,you should refer to NAVAIR 16-30PRC 90 forthe most current shelf life information.

Operating Procedure

Refer to table 5-2 for the functions of eachcontrol on the PRC-90. The set is operated asfollows:

1. Free the antenna from its stowed positionby pulling its end from the retaining ring or band

Table 5-2.—Operating Controls and Indicators

Control orIndicator Control Position Function

Function switch OFF Completely removes power from radio set.VOICE/MCW Turns on the guard channel receiver to243.0 the emergency frequency of 243.0 MHz. Also

enables voice and MCW guard channeltransmission which are keyed by the PUSHTO TALK or MCW buttons.

BCN 243.0 Turns on 243.0 MHz guard channel transmit-ter, and transmits a beacon tone. Swept audiotone is continuously transmitted for rescue air-craft to home on.

VOICE 282.8 Turns on alternate channel to receive on 282.8MHz. Also enables voice transmission on

NOTE auxiliary channel when PUSH TO TALKThe button, (9, figure button is depressed.5-8) must be de-depressed to placefunction switch in theVOICE 282.8 posi-tion.

PUSH TO TALK Depressed Turns receiver off and turns transmitter onbutton when function switch is in either

VOICE/MCW 243.0 or VOICE 282.8 position.Best voice transmissions are obtained whenspoken directly into the talk microphone.

Released Turns off transmitter and turns on receiver;received signal is heard with ear close toLISTEN speaker or earphone.

5-8

Table 5-2.—Operating Controls and Indicators—Continued

Control orIndicator Control Position Function

MCW button This button is a telegraph key; it enables theoperator to transmit code when the normal trans-mitting level of his voice may reveal his position.MCW is only obtainable when the functionswitch is in the VOICE/MCW 243.0 position.

Depressed Causes radio set to transmit a continuous tone,receiver off.

Released Turns transmitter off, receiver on.

VOL control This controls the volume of the sound fromthe LISTEN speaker or earphone. It controlsreceived signals, not sidetone.

Fully Up, MAX Loudest sound

Fully down Quietest sound, but radio set is not turned off.

NOTE

Volume control does not affect transmittedpower output.

LISTEN speaker Sound of received signal is heard by placing earclose to LISTEN speaker. Sound of MCW orbeacon transmitter may also be heard. TheLISTEN speaker is shut off when the earphone isconnected.

TALK microphone Picks up the voice being transmitted when PUSHTO TALK button is depressed and functionswitch is set to either VOICE/MCW 243.0 orVOICE 282.8.

Earphone jack Earphone Causes sound to be heard in earphone. A magnetconnected in the earphone connector (12, figure 5-8) shuts

off the LISTEN speaker.

NOTE

Connector may bejoined to jack ineither of twopolarities.

Earphone Sound is heard through LISTEN speaker.disconnected

Battery cap Holds battery in place.

5-9

as appropriate. The antenna snaps into an uprightposition. Fully extend all five telescopic sectionsof the half-wave antenna by grasping it by its tipand pulling outward.

2. Set the function switch to the mode ofoperation that you want. The function switch isset by rotating the thumb knob on the right-handside so that the arrow points to the mode selected.The function switch is detented and clicks intoeach position. Rotate the knob down one click(from OFF) for VOICE/MCW 243.0 operation,or two clicks for BCN 243.0 operation. ForVOICE 282.8 operation (secondary channel),push the button with the arrow and rotate thefunction switch knob up one click.

3. For voice operation, hold the radio set andadjust the VOL control. To transmit, push downthe PRESS TO TALK button and speak directlyinto the TALK microphone.

4. If guard channel steady-tone transmissionor Morse code operation is desired, set thefunction switch to VOICE/MCW 243.0. Depressthe MCW button to transmit the tone. Listen forthe sidetone in the LISTEN speaker or earphonewhile the MCW button is depressed. This sidetoneindicates proper transmitter operation.

5. For guard channel beacon operation, setthe function switch to BCN 243.0. The transmitter

239.439Figure 5-9.—Beacon set, radio, AN/URT-33A (front view).

continuously sends the swept-tone beacon signalat this setting. Listen for the sidetone as anindication of proper operation. In the beaconmode, the sidetone is a chirping sound.

NOTE: Since the transmitter is keyedautomatically in the beacon mode, andsince continuous transmission may beneeded for a prolonged period of time, theAN/PRC-90 may be placed upright on aflat surface. It will then transmitautomatically.

AN/URT-33A BEACON SET RADIO

The Beacon Set Radio, AN/URT-33A (figs.5-9 and 5-10), is an emergency radio beacontransmitter that, when properly actuated,transmits a tone-modulated radio frequency signalon the emergency guard frequency of 243.0 MHz.

Although the AN/URT-33A was designed tobe placed into a parachute pack, the Navynormally places the beacon radio into the seat pan(RSSK) or life rafts. Instructions for properlyrigging the AN/URT-33A can be found inNAVAIR 13-1-6.1.

The AN/URT-33 radio has two types ofantennae. One type is the flexible wire antenna.This antenna is used during parachute descent

239.440Figure 5-10.—Beacon set, radio, AN/URT-33A (rear view).

5-10

since the radio is activated when the aircrewmanleaves the aircraft.

The flexible wire antenna serves as theprincipal antenna during descent. Upon landing,the flexible antenna is removed by the air-crewman, and a telescopic antenna that is builtinto the radio is used.

The AN/URT-33A radio is battery-operated.The battery is a mercury type with a storage lifeof 24 months, provided that the storage tempera-ture is 70°F. At a storage temperature of 100°F,the storage life is only 12 months. For survivalequipment applications, such as rigid seat survival

kits and life rafts, the service life of the batteryassembly is 2 years from the date of manufacture,225 days from the date placed into service, or 231days for the SKU-2/A or RSSK-7 seat survivalkit. Ensure that the battery service life does notexpire prior to the next scheduled inspection ofthe assembly in which the radio beacon set isinstalled.

AN/PRT-5 TRANSMITTING SET

Transmitting Set, Radio AN/PRT-5 (fig.5-11) is a battery-operated, emergency beacon

239.441Figure 5-11.—Transmitting set, radio, AN/PRT-5, identification of components.

5-11

transmitter that, when properly activated,transmits a tone-modulated radio frequency signalon the emergency guard frequencies of 8.364 MHzand 243.0 MHz simultaneously. The transmittingset includes an inflatable float assembly that keepsthe transmitting set afloat at sea, and provides asupport platform on land. The entire set is packedin a carrying case for stowing in a life raft.

The transmitting set is intended for signalingthe location of downed aircraft or airmen.Because it provides signals in both the highfrequency (HF) and ultra high frequency (UHF)portions of the spectrum, it can be detected bysearch aircraft, surface vessels, and coastal-basedstations at considerable distances.

The battery pack is designed to provide 72hours of continuous operation at 25°C (77°F)with at least 250 milliwatts of output from eachtransmitter at the end of this period. Thetransmitting set will continue to transmit until thebattery pack is completely discharged.

Modulation of the transmitter is by internalmeans only. No provision has been made for voiceor code communications, or for receiving signalsfrom search craft.

To prepare the radio for use is a simpleprocedure.

1. Pull the free end of the UHF antennathrough the grommet in the float assembly toallow the antenna to stand vertically.

2. Unscrew the top section cap of thetelescopic HF antenna, and pull the antenna outto its full length. When fully raised the antennasections are alternate black and gray with the topsection gray. The antenna, when fully extended,is approximately 9 feet high. (See figure 5-12.)

3. Pull out the switch safety pin (fig. 5-11).4. Turn the POWER toggle switch to ON (fig.

5-11).5. Place the entire assembly in the water and

tow it behind the life raft.6. When operating on land, be sure the

transmitting set is placed on level ground so thatthe antennas are vertical. Do not stand close tothe transmitting set because this can cause changesin the radiation pattern of the transmitted signals.

7. If desired, the safety pin can be replacedto prevent the transmitting set from being turnedoff accidentally.

HELICOPTER RESCUE DEVICES

Every Aircrew Survival Equipmentman shouldbe familiar with the equipment used in rescue

Figure 5-12.—Transmitting set, radio,flotation collar.

239.442AN/PRT-5 with

from the sea or land by helicopters. (Refer toNavy Search and Rescue Manual, NWP 19-1, forprocedures and techniques involving at-seaaircrew rescues.) The helicopter’s ability to landand takeoff in a small area and to hover over aspot lends itself very effectively to rescue work.

There are three methods by which a helicoptermay make a rescue. The first is by hovering, thesecond by landing, and the third by making a low,slow pass with the rescue device hanging nearground level. The latter is used mainly in hostileareas when the helicopter pilot does not wish topresent the aircraft or the survivor as a stationarytarget for enemy gunners. By far, the mostcommon helicopter pickup is made by hovering.

5-12

NOTE: A static charge of electricity is builtup in the helicopter and must be dissipatedby grounding. Do NOT touch the rescuedevice until after it has contacted theground or water to permit the dischargeof static electricity and prevent electricalshock.

Research, development, test, and evaluationof air rescue devices has been continuous sincethe helicopter became the primary rescue vehicle.The various types of rescue devices, theirfunctions, and associated maintenance proceduresare discussed in the sections that follow.

All helicopter rescue devices must be scheduledinto periodic maintenance under the direction andcontrol of the maintenance/material controlofficer to which the equipment is assigned.Maintenance must be thorough at all times. Noinstance of careless treatment or willful neglectof aircrew personal protective equipment will becondoned. The vital function of the equipmentmust be uppermost in the minds of all personnelconcerned.

Individual paralofts normally store andmaintain all helicopter rescue devices, andcheckout is on an individual basis. Because of thelack of individual identification of the rescuedevices, it is impossible to match the AviationCrew Systems History Card to the rescue device.All rescue devices should be locally serialized byindividual paralofts to ensure positive control ofinspection cycles performed on helicopter rescue

239.404AFigure 5-13.—Survivor’s sling.

devices.

SURVIVOR’S SLING

The survivor’s sling is a buoyant deviceconsisting of a kapok filling encased in a brightyellow waterproof cover to make it highly visibleduring rescue operations. Webbing, reevedthrough the cover with both ends terminating intwo V-rings, is used to attach the sling to thehelicopter rescue hook. Two retainer straps, onelong with a quick-ejector snap and one short witha V-ring, are fastened to the webbing of the slingand are enclosed in slide fastener-securedenvelopes. Refer to figures 5-13 and 5-14.

The survivor’s sling (also known as the “horsecollar” and rescue sling) is used to assist personnelperforming rescue work from a helicopter overwater or land. The survivor’s sling is lowered ona hoist cable from a helicopter to the rescueswimmer and survivor. The sling is designed to 239.404Baccommodate one survivor at a time. Figure 5-14.—Survivor’s sling retainer straps pulled out.

5-13

Maintenance

The aircrewman’s responsibility y for mainte-nance of the survivor’s sling is limited to a fresh-water wash. Repairs or other actions areperformed by organizational-level maintenance orabove.

All survivor’s slings are subject to a calendarinspection upon issue and at intervals not toexceed 225 days. All survivor’s slings are subjectto a preflight inspection also. This action isperformed by the aircrewman before each flightand at least every 14 days. This inspection consistsof a visual inspection outlined in the calendarinspection procedures.

Calendar Inspections

The calendar inspection consists of a visualinspection and a proof load test.

To perform the visual inspection, proceed asfollows:

1. Inspect all fabric for cuts, deterioration,and abrasion.

2. Inspect seams for proper adhesion andstitching.

3. Inspect the retainer straps for security ofattachment and wear.

4. Inspect all hardware for security ofattachment, corrosion, damage, wear, and, ifapplicable, ease of operation.

5. Inspect all markings. If the markings arefaded or incorrect, they must be corrected byusing black washproof ink.

The proof load test is performed on thesurvivor’s sling during the calendar inspection andafter each flight in which saltwater immersion hasoccurred. To perform a proof load test, proceedas follows:

1. Allow the sling to dry completely.2. Inspect for damage to webbing of

survivor’s sling. Damage other than frayed orseparated stitches is cause for replacement.

3. Place the survivor’s sling in a webbingtesting machine.

NOTE: If a webbing testing machine is notavailable, refer to NAVAIR 13-1-6.5 fora suitable alternate testing method.

4. Apply a load of 500 pounds at a rate of1 inch per minute.

5. Again, inspect for any damage to thewebbing of the survivor’s sling. Damage otherthan frayed or separated stitches is cause forreplacement.

6. Remove the sling from the webbing testingmachine. ,

The survivor’s sling must be cleaned afterevery immersion in salt water. To clean thesurvivor’s sling, proceed as follows:

1. Clean the sling and its cover with a mildsoap and water solution. Rinse well with freshwater.

2. Dry the sling and its cover with a clean, dry,lint-free cloth.

RESCUE SEAT

The rescue seat is a buoyant aluminum deviceconsisting of a hollow flotation chamber and athree-pronged seat, with prongs 120 degrees apart(fig. 5-15). Lead is inserted in the base of the

239.405Figure 5-15.—Helicopter rescue seat.

5-14

assembly to minimize roll and to provide theproper degree of submergence of the seat in thewater. A safety strap is provided to assist thesurvivor to remain in the seat during hoisting tothe helicopter. The flotation chamber and hoistbracket of the seat are bright orange. The lowerseat assembly is yellow for high visibility.

The helicopter rescue seat is intended for usein retrieving survivors and assisting the rescueswimmer in performing rescue operations whenit is difficult to make a helicopter landing overland or water.

When conducting a rescue, the helicopterrescue seat is lowered on a hoist cable from ahelicopter to the rescue swimmer and survivor.The rescue seat is designed to accommodate oneperson at a time.

Maintenance

The aircrewman’s responsibility formaintenance of the rescue seat is limited tofreshwater wash after usage. Repairs or othermaintenance actions required are performed byorganizational-level maintenance or above.

Inspection

All rescue seats are given a calendar inspectionupon issue and at intervals of 225 days. Thecalendar inspection is a visual inspection. Tovisually inspect the condition of the rescue seat,proceed as follows:

1. Inspect all components for security ofattachment, corrosion, damage, wear, discolora-tion, and ease of operation.

2. Check for sharp edges or projections.3. Check material for imperfections or

damage.4. Check safety strap for fraying or tears.5. Compare markings on seat to markings

listed in applicable table in NAVAIR 13-1-6.5.

If the markings are faded, restore them withblack washproof ink. If marking is incorrect,paint it out and enter the correct marking as closeto the proper location as possible, using blackwashproof ink.

Cleaning

The rescue seat must be cleaned after everyimmersion in salt water. Clean it as follows:

1. Wash the rescue seat with a mild soap andwater solution. Rinse well with fresh water.

2. Dry the rescue seat with a clean, dry, lint-free cloth.

3. Return the seat to service.

FOREST PENETRATOR ANDFLOTATION COLLAR

The forest penetrator is bright yellow for highvisibility, and is a compact device weighing about21 1/2 pounds. The forest penetrator is 34 incheslong and 8 1/8 inches in diameter with the threeseats retracted, and 26 inches in diameter with theseats extended. Each seat is 4 3/4 inches wide, 111/2 inches long, and is spring-loaded in theretracted position (flush against the shaft of thepenetrator). A spring-loaded retaining latch isprovided under each seat to secure the seat in theextended position. To release the seat, push downon the seat and pull down on the latch. The seatthen snaps back into the retracted position. Threewebbing safety straps are provided to hold thesurvivors in place. Each strap extends 4 feet 9 1/4inches, with an adjustable quick-ejector hookattached to the upper section of the penetrator.The straps terminate with a yellow fabric, markedTIGHTEN. Yellow webbing tabs (with hook tape)marked PULL OUT are sewn to the safety strapsfor attachment to fabric cover stowage openings.The yellow fabric cover has a 17-inch slide fastenerand three stowage openings (with pile tape forsecuring safety straps). (See figure 5-16.)

239.406AFigure 5-16.—Forest penetrator.

239.406BFigure 5-17.—Flotation collar installed on forest penetrator.

The flotation collar is made of bright orangefoam rubber for high visibility and weighs about1 1/2 pounds. (See figure 5-17.) It is 2 1/4 incheslong, with a 7 3/4-inch diameter at the top anda 4-inch diameter at the bottom. When theflotation collar is installed on the forest pene-trator, the retracted diameter at the penetrator is9 inches.

The forest penetrator and flotation collar areintended to assist the rescue swimmer to performrescue operations in the water or to rescuesurvivors on land.

The flotation collar is a device that, whenfastened around the forest penetrator, allowsflotation of the complete assembly during air-searescue operations.

During land rescue operations, the forestpenetrator is lowered to the survivor with the seatsretracted. For sea operations the forest penetratoris lowered to the rescue swimmer and survivorwith the flotation collar installed, safety strapshanging free, and the seats retracted. In thisconfiguration, the penetrator will float its topabout 6 inches above the surface of the water.

The forest penetrator is designed toaccommodate one, two, or three survivors at thesame time.

Maintenance

The aircrewman’s responsibility for mainte-nance of the forest penetrator is limited to washingwith fresh water. Repairs or other actions areperformed by organizational-level maintenance orabove.

Inspection

All forest penetrators receive a calendarinspection upon issue and at intervals not toexceed 225 days. The calendar inspection consistsof visually inspecting both the forest penetratorand flotation collar.

When inspecting the condition of the forestpenetrator and flotation collar, examine thefollowing:

1. All fabrics for cuts, tears, deterioration,and abrasion.

2. Seams for proper stitching.3. Straps for security of attachment and wear.4. Any other parts for wear, damage, and

security of attachment.5. All hardware for security of attachment,

corrosion, damage, wear, and, if applicable, easeof operation.

6. The cover for strains, dirt, and generalcondition.

7. The slide fastener for damage, corrosion,and ease of operation.

8. Compare markings on the forest penetratorand flotation collar to markings listed on theapplicable tables in NAVAIR 13-1-6.5. Restoreany faded markings, and correct markings, ifnecessary, with indelible ink.

Cleaning

The forest penetrator and flotation collar mustbe cleaned after every immersion in salt water asfollows:

1. Wash the penetrator and collar with a mildsoap and water solution. Rinse well with freshwater.

2. Wipe the penetrator and collar with clean,lint-free cloth and allow to dry.

3. If necessary, apply silicone lubricant toslide fasteners on the cover of the penetrator toensure ease of operation.

5-16

4. Apply a lubricating oil to all pivot pointsof the penetrator. Wipe off excessive lubricatingoil.

5. Return both assemblies to service.

RESCUE NET

The rescue net looks like a conically shapedbirdcage with an opening on one side. The netweighs approximately 20 pounds and is brightyellow for high visibility. To stabilize the net dur-ing use, a sea anchor is provided. A 10-foot sea

anchor retaining line with two single snap hooks isalso provided. One halyard snap hook permitscomplete removal of the sea anchor from the net,while the other snap hook permits shortening ofthe sea anchor to 5 feet to be used in moderateseas. During high seas, the 10-foot retainer line isused. The rescue net has a snap lock lower frameand three upper support ribs with sliding sleevesthat form a rigid cage when the net is fullyextended. Foam plastic floats are provided on therigid upper frame of the net. (See figure 5-18.)

239.407Figure 5-18.—Rescue net, parts nomenclature.

5-17

The rescue net is used to assist the rescueswimmer performing rescue work from ahelicopter over water or land. The rescue net mayalso be used to ferry or pick up cargo.

WARNING

THE SEA ANCHOR MUST NOT BEUSED WHEN HOISTING PERSONNELOUT OF THE WATER.

Maintenance

The aircrewman’s responsibility formaintenance of the rescue net is limited to a

freshwater wash after use. Repairs or other actionsrequired are performed by organizational-levelmaintenance or above.

Inspection

All rescue nets are given a calendar inspectionupon issue and at intervals of 225 days. Thecalendar inspection for the rescue net consists ofthe following visual inspection:

1. Erect the net by unfolding its lower frameassembly and forcing the assembly down. Theframe will snap open.

2. Suspend the open section of the net andslide sleeves or the upper support ribs between theswivel joints. The sleeves rest on the support ribstops.

3. Inspect all hardware for security ofattachment, corrosion, damage, wear, and easeof operation.

Cleaning

To clean the rescue net, proceed as follows:

1. Wash the rescue net with a mild soap andwater solution. Rinse well with fresh water.

2. Allow the net to air dry.

RESCUE HARNESS

The rescue harness consists of nylon webbingshoulder straps, riser straps, back strap, anadjustable chest strap, and a lifting strap (fig.5-19). The end of the lifting strap, equipped witha gated D-ring, adapter assembly, releaseassembly, and parachute harness triangle link arestowed in a pouch on the front of the harness.

A handle on the pouch allows for ease ofaccessibility of the gated D-ring during rescueoperations. Right and left pocket assemblies arelocated at each junction of the riser and liftingstrap. The left pocket is designed to hold one Mk13, Mod 0 marine smoke and illumination signaland the right pocket is designed to hold the otherMk 13, Mod 0 marine smoke and illuminationsignal and the suspension line cutter. A knifescabbard is attached to the left side of the liftingstrap.

The rescue harness is designed specifically tobe worn by the rescue swimmer, providing himmaximum mobility and a means for performingrescue operations in the water.

Maintenance

The aircrewman’s responsibility formaintenance of the harness is limited to freshwaterwash after usage. Repairs or other maintenanceactions required are performed by intermediate-level maintenance or above unless otherwisespecified.

Preflight Inspection

The rescue harness preflight inspection isaccomplished prior to each flight, and at intervalsnot to exceed 14 days. This inspection is made bythe aircrewman. To perform a preflightinspection, examine the following:

1. Fabric and webbing for cuts, tears, openseams, and loose or broken stitching

2. Signs of contamination, such as stains anddiscoloration

Calendar Inspection

The calendar inspection is performed byorganizational-level maintenance or above uponissue before placing the rescue harness in serviceand every 90 days thereafter. To perform thecalendar inspection, proceed as follows:

1. Service life check. The service life ofthe rescue harness is 7 years from the dateit was placed in service or 8 1/2 yearsfrom the date of fabrication, whichever oc-curs first. When an assembly reaches its

5-18

239.408Figure 5-19.—Rescue harness.

service life limit, it is removed from service andscrapped. To perform a service life check, proceedas follows:

a. When a rescue harness is placed inservice, the start of service date is stenciled on theinside of the chest strap.

b. When an in-service rescue harness lacksa start service date, service life expires 7 yearsfrom date of manufacture.

c. The date of manufacture is located onthe inside of the chest strap.

5-19

2. Contamination inspection. To inspect arescue harness for acid or alkaline contamination,proceed as follows:

CAUTION

ENSURE THE AREA TO BE TESTEDIS ISOLATED FROM ANY SOURCEOF CONTAMINATION THAT MAYRESULT IN ERRONEOUS READINGS.

a. Dampen the suspected area with distilledwater.

b. Place a piece of full-range test paper onthe dampened area. Compare it to the colorstandard provided with the paper. The color itchanges to indicates the approximate pH readingand which specific short-range test paper to use.

c. Place the short-range test paper on thedampened area. Its color indicates the pH factorof the affected area.

d. If acid contamination is found, theassembly must be considered nonrepairable andscrapped.

e. If alkaline contamination is found, rinsethe assembly in cool, fresh water until a safe read-ing is obtained. All fabric and webbing must thenbe carefully inspected for any sign of deteriora-tion.

3. Visual inspection. To inspect the rescueharness, examine the following:

a. Harness webbing for cuts, tears,fraying, deterioration, and security of stitching.

b. Front pouch and right and left pocketsfor cuts, tears, fraying, deterioration, and securityof stitching.

c. Gated D-ring and all other hardware forcorrosion, distortion, sharp edges, security ofattachment, and ease of operation.

d. Hook and pile tape fasteners forcondition and proper mating.

Cleaning

Clean the rescue harness as often as necessaryto remove perspiration stains, dirt, and otherstains that may degrade performance of theassembly. To clean a rescue harness, proceed asfollows:

1. Wrap all metal fittings in heavy flannelcloth.

CAUTION

DO NOT SCRUB RESCUE HARNESS.

2. Soak the assembly in cool, fresh water for2 to 3 hours to loosen any set stains.

3. Drain this water and immerse the harnessin a tub of fresh water (not over 120°F). Gentlyagitate by hand.

4. After 5 to 10 minutes of agitating, repeatstep 3.

5. Petroleum and other stubborn stains maybe removed by repeated applications of a mildsoap and water solution. Each application mustbe followed by a rinse in cool, fresh water.

239.409Figure 5-20.—Rescue hook.

6. Hang the rescue harness on a woodenhanger until dry.

RESCUE HOOK

The rescue hook consists of one large hook,an adjacent small hook, and ring located at thebottom of both-hooks. A bearing assembly isattached to the upper section allowing the hookto rotate freely about its axis. The large hooksupports 3,000 pounds and is used to hoistpersonnel. The smaller hook supports 1,000pounds and is used to hoist equipment. The ringat the bottom supports 1,500 pounds and is alsoused to hoist miscellaneous equipment. Bothhooks have a spring-loaded latch to preventinadvertent release of personnel or equipment.(See figure 5-20.)

The rescue hook is attached to the hoist cableand is used to assist rescue personnel inperforming rescue operations from a helicopter.The rescue hook can hoist personnel and/orequipment during both sea and landrescues.

Maintenance

The aircrewman’s responsibility ismaintenance control if equipment

helicopter

to informhas been

immersed in salt water. Repairs or other actionsrequired are performed by organizational-levelmaintenance or above.

5-20

Calendar Inspection

All rescue hooks get a calendar inspectionupon issue and at intervals to coincide with theaircraft cycle. In no case shall the intervalsbetween calendar inspections exceed 225 days. Thecalendar inspection consists of the following visualinspection:

1. Inspect for missing, bent, fractured ordamaged components.

2. Check hardware for security of attachment,corrosion, wear, and ease of operation.

3. Check for sharp edges and projections.

Cleaning

Clean the rescue hook after every immersionin salt water. To clean the rescue hook, proceedas follows:

1. Clean devices with an acceptable cleaningagent.

2. Remove all foreign objects with low-pressure air.

3. Lubricate all moveable parts of the rescuehook. Wipe off excess lubricant with a clean, dry,lint-free cloth.

4. Return the rescue hook assembly to ser-vice.

HOIST QUICK-SPLICE PLATE

The hoist quick-splice plate is made of1/4-inch aluminum, 6 5/8 inches in length by 3inches wide. The corners are rounded off andholes are grooved in places where the hoist cablerests. A stainless steel clip, 1/32 inch thick, isattached to the plate with two, 5/32-inch steelrivets. A rescue hook is attached to the plate withthimbles, swaging sleeve, and a length of hoistcable. The distance between the rescue hook andthe plate is 6 inches. (See figure 5-21.)

The hoist quick-splice plate is used when thehoist cable is cut or broken during a rescueoperation. It is used when time is a factor and noother means are available for rescue.

239.410Figure 5-21.—Hoist quick-splice plate.

Maintenance

The aircrewman’s responsibility for mainte-nance of the hoist quick-splice plate is limited togiving it a freshwateractions are performedmaintenance or above.

Calendar Inspection

wash. Repairs or otherby organizational-level

All hoist quick-splice plates are given acalendar inspection upon issue and at intervals of225 days. The calendar inspection consists of avisual inspection for bends, corrosion, sharpedges, and projections.

Cleaning

You have to clean the hoist quick-splice plateafter every immersion in salt water. To clean it,proceed as follows:

1. Clean with an acceptable cleaning agent.2. Dry with a lint-free cloth.

CABLE GRIP

The cable grip (which opens and closes on thecable) and a shackle enable the cable grip to beattached to the crewman’s safety belt to take theweight off the hoist assembly during a hoist

5-21

239.411Figure 5-22.—Cable grip.

failure. The cable grip is capable of supporting1,000 pounds. (See figure 5-22.)

The cable grip is an emergency conditiondevice used by personnel performing rescueoperations from a helicopter when the rescue hoisthas a malfunction that renders the hoistinoperable. The cable grip is used for quicktemporary attachment to the hoist cable.

Maintenance

The aircrewman’s responsibility formaintenance of the cable grip is limited to afreshwater wash and to informing maintenancecontrol that it has been used. Repairs or otheractions required are performed by organizational-level maintenance or above.

Calendar Inspection

All cable grips are subject to a calendarinspection upon issue and at intervals of 225 days.To inspect the condition of the cable grip, proceedas follows:

1. Inspect for missing, bent, fractured ordamaged components.

2. Check hardware for security of attachment,corrosion, wear, and ease of operation.

3. Check for sharp edges and projections.

Cleaning

Clean the cable grip every time it has beenimmersed in salt water. To clean it, proceed asfollows:

1. Clean devices with an acceptable cleaningagent.

2. Remove all foreign objects with low-pressure air.

3. Lubricate all movable parts of the cablegrip with lubricating oil. Wipe off any excess oilwith clean, dry, lint-free cloth.

PNEUMATIC RESCUE HAND TOOL

The pneumatic rescue hand tool is a cartridge-operated device. A chamber within the handlesecures a 3,000 psi nitrogen gas cylinder, whichprovides a very powerful force against the cuttingblade.

The case is made of nylon webbing, 12 1/2inches long and 5 3/4 inches wide at thetop, tapering to 3 1/4 inches wide at thebottom. A 46-inch lanyard and baby swivel hook,attached to the upper grommet, are designed for

5-22

239.412Figue 5-23.—Pneumatic rescue hand tool.

attachment to the pneumatic rescue hand tool.(See figure 5-23.)

The pneumatic rescue hand tool is designedfor helicopter rescue crewman to use duringair/sea rescue operations.

The pneumatic rescue hand tool gives thecrewman a readily available cable cutter andparachute harness webbing cutter. The tool cancut single strands of stainless steel cable up to 7/32inch in diameter as well as harness webbing ofthickness up to and including 1/4 inch and widthsup to 1 3/4 inch, in single cuts. The pneumaticrescue hand tool, complete with case, should bereadily available to the rescue crewman duringrescue operations.

Maintenance

The aircrewman’s maintenance of the pneu-matic rescue hand tool is limited to a freshwaterrinse. Repairs or otherrequired are done bymaintenance or above.

maintenance actionorganizational-level

Calendar Inspection

The pneumatic rescue hand tool is in-spected upon issue and at intervals not toexceed 225 days. The calendar inspection con-sists of a visual inspection and a functional test.To perform a visual inspection, proceed asfollows:

1. Inspect all parts for corrosion, cracks,wear, and any other defects.

2. Inspect blade for sharpness. Sharpen, usingan appropriate whetstone, or replace as necessary.

3. Inspect the anvil for scored surface.

The functional test consists of the followingtasks:

1. Leakage test. To perform a leakage test,proceed as follows:

a. Pressurize the hand tool to 3,000 psiwith a nitrogen cartridge.

b. Immerse the pressurized hand tool infresh water and rotate the tool in three directionsto eliminate any trapped air in external pockets.

c. Any leakage after 1 minute indicates adefective seal of the component from which thegas is escaping. Replace seals as necessary.

2. Trigger force test. To perform a triggerforce test, proceed as follows:

a. Mount the pressurized hand tool in anappropriate fixture, cradle or V-block.

b. Using a push-pull scale, measure thetrigger force necessary to actuate the blade on thefirst stroke. The force is applied midway on thefinger area of the trigger. Two thicknesses of TypeXIII, MIL-W-4088C, webbing should be cut. Thetrigger force is between 5 and 20 pounds. Triggerforce outside this range indicates the need forrepair of the trigger (forward) valve or the triggerassembly.

3. Performance. To conduct a performancetest, proceed as follows:

a. Cut a double thickness of webbing, andwith the trigger in the depressed position, immersethe hand tool in water.

b. Any leakage after 1 minute ofimmersion indicates the piston seal leaks or theexhaust (rear) valve leaks.

c. Make 10 additional double webbingcuts. After the tenth cut, with the triggerdepressed, immerse the hand tool in water.

5-23

d. Check for leakage during 1 minute ofimmersion. Any leakage indicates the trigger(forward) valve is faulty.

e. Make additional cuts of double webbinguntil the hand tool fails to cut through boththicknesses. The total number of cuts shouldexceed 10.

f. Failure to make 10 cuts indicatesmaintenance is required.

Cleaning

Clean the pneumatic rescue hand tool afterevery immersion in salt water. To clean, proceedas follows:

1. Rinse the hand tool thoroughly in freshwater (preferably distilled) and air dry, using aforced warm air source.

2. After cleaning the hand tool, lightly coatthe cutting edge of the blade with pneumaticgrease.

5-24

CHAPTER 6

INFLATABLE SURVIVAL EQUIPMENT

Learning Objective: Upon completion of this chapter, you will be able torecognize, inspect, and maintain inflatable survival equipment.

Since naval air operations are predominantlyover water, the Navy has developed highly reliableand versatile inflatable equipment designed tomeet the needs of aircrew personnel in a watersurvival situation.

The versatility seen in current inflatablesurvival equipment meets the ever increasing anddiverse needs of the fleet. For example, the lifepreserver provides more than enough buoyancy tosupport a person with all survival gear donned,but not sacrifice comfort or adversely restrictmovement in the water. It does not interfere withthe aircrew member’s ability to perform his/herduties aboard the aircraft. The life preserveris flame resistant, lightweight, and has thecapability to contain certain survival items.The life preserver is reliable and will save a life,if used properly.

Life rafts provide protection from the cold andhostile environment of the sea. For single- anddual-seat aircraft, a one-man life raft adequatelyfulfills this function. However, for large aircraft,the 4-, 7-, 12-, or 20-man life rafts will beused. In addition to providing protection from theenvironment, these rafts carry an adequatenumber of survival items for their capacity, butare still light enough to carry.

Naval aircraft making operational flights overwater are required to carry rafts that willaccommodate all the assigned crew, plus pas-sengers. These rafts are manufactured in varioussizes and configurations to meet the demands ofall type of aircraft.

Pneumatic rafts are compact assemblies,which can be stowed in a small area. They shouldbe stowed so they are readily accessible, preferablynear an emergency exit. Never stow a raft underother equipment or cargo or near batteries. Pro-tect them from heaters, engines, auxiliary powerunits, electronic tubes, or other sources of heat.

If the aircraft flight manual designates astorage place for rafts, this space will be used,unless you are otherwise directed by competentauthority. Whenever possible, stow rafts in thesame manner in all aircraft of the same model.This enables the crew to become familiar withtheir location, and thus avoid confusion in theevent of a ditching.

Rafts are constructed of rubber-impregnatednylon fabric; therefore, they are susceptibleto damage from maltreatment. However, whenafloat at sea, they are surprisingly strong anddurable, and have a tenacious stability. It is yourresponsibility as a PR to inspect, pack, andmaintain all of the various types of rafts andrelated equipment carried in aircraft.

INSPECTIONS

All inflatable survival equipment will besubjected to periodic maintenance under thedirection and control of the maintenance/materialcontrol officer of the activity to which theequipment is assigned. Maintenance must bethorough at all times. No instance of carelesstreatment or willful neglect of inflatable survivalequipment will be allowed to go unnoticed. Thevital function of this equipment must be upper-most in the minds of all personnel concerned. Theperiodic inspection cycles should coincide with thespecific aircraft inspection cycles specified inOPNAVINST 4790.2 (series), or personal issueequipment cycle, as applicable.

To meet unusual situations and aid workloadscheduling, a period of plus or minus 1 week,or portion thereof, may be applied to theauthorized inflatable survival equipment calendarmaintenance interval. A period of plus or minus

6-1

10% may be applied to equipment in phasedmaintenance aircraft.

The five different types of life rafts used innaval aviation are the LR-1 and LRU-7/P, whichare one-man rafts; the LRU-12/A, which is afour-man raft; the LRU-13/A, which is a seven-man raft; the LRU-14 series, which is a 12-manraft, and the LRU-15/A, which is a 20-man raft.

You may be required to work on only one oryou may work on all of them. All require the samethree inspections—preflight, special, andcalendar/phase.

The preflight inspection is performed onfuselage-installed life rafts before the first flightof the day. This inspection is done by linepersonnel (plane captain or delegated aircrewman)who have been designated by the line divisionofficer, instructed, and found qualified by theaviators equipment branch.

The special inspection is performed onfuselage-installed life rafts every 30 days. Thisinspection is made at the organizational level ofmaintenance by personnel assigned to the aviatorsequipment branch. Upon completion of theinspection, the date of inspection and inspector’ssignature are entered in the inspections section ofthe Aviation Crew Systems History Card.

To perform a preflight/special inspection,visually inspect for the following:

1.

2.3.4.

5.

6.

Fabric for cuts, tears, deterioration, andabrasionSeams for proper adhesion or stitchingStraps and handles for security and wearAny other parts for wear, damage, andsecurityAll hardware for security of attachment,corrosion, damage, wear, and, if ap-plicable, ease of operationLife raft retaining line for proper stowage

CAUTION

DO NOT OPEN RAFT ACCESSDOORS, RSSK KITS, OR ANY SEALEDOR SAFETY-WIRED PORTION OFTHE LIFE RAFT FOR THIS INSPEC-TION.

Subject each life raft to the calendar/phaseinspection before you place it in service, or if itis an aircraft inventory item at the time of theaircraft acceptance inspection. Thereafter, thecalendar/phase inspection interval coincides with

the aircraft inspection cycle in which it is installed.See the applicable Planned Maintenance System(PMS) publications for specific intervals. In nocase will the interval exceed 231 days except thatthe LR-1 (RALSA) inspection is not to exceed 453days. Unless operational requirements demandotherwise, the life raft calendar/phase inspectionis performed at the intermediate level ofmaintenance or above.

The acceptance/calendar/phase inspectionconsists of the following major tasks (to beperformed in the order listed):

1.2.3.4.5.6.7.8.

Container/case inspectionFunctional test (if required)Pull cable proof load test (if required)VisualInflation assembly inspectionLeakageRecords updatingRepacking

Details are listed in NAVAIR 13-1-6.1.

A functional test and pull cable proof load testare performed prior to placing a raft in serviceor during an aircraft acceptance inspection, andeach fourth inspection cycle thereafter. You mustmake a leakage test at each inspection cycle. Ifthe inspection indicates any damage beyondcapability of maintenance, you must forward theentire assembly to supply.

DETERMINATION OFREPAIRABILITY

Life rafts are considered beyond repair for anyof the following reasons:

1.2.3.

4.

5.

6.

Porous fabric areas on tubesSplit or open tube seamsLeakage test failure resulting from otherthan a cut, tear, or punctureDamaged or malfunctioning inlet valve,manifold, or oral inflation tubeDamaged or malfunctioning topping-offvalve that cannot be corrected byreplacement of the topping-off valveopening insertMultiplace rafts (leaky bulkheads)

FUNCTIONAL TEST

Before functionally testing a life raft, youshould make sure you have enough area to inflate

6 - 2

the life raft. Remember to take into considerationthe inflated size of the raft; an LRU-15/A willtake 20 times the area that an LR-1 requires.

To begin the test, you first open the carryingcase and unfold the life raft. All life rafts havean inflation assembly, and by pulling an actuatingcable, you automatically inflate the raft with CO2.

When you do this, the raft should inflate todesign shape, without evidence of restriction, inless than 1 minute. This is a CDI inspection point,so have a CDI inspector watching before you pullthe cable. Once the raft is inflated, examine it forobvious defects such as cuts, tears, rupturedseams, and damaged manifold.

PULL CABLE PROOF LOAD TESTFOR MULTIPLACE RAFTS

The pull cable proof load test for multiplacerafts is done in conjunction with the functionaltest. Also, the test must be performed prior toplacing an inflation assembly into service. Firstremove the inflation valve cover plate andremove the pull cable from the valve. Thenapply a 50-pound pull force between the cableball and the snap hook to determine if the cableis strong enough for the system.

Examine the pull cable for broken strands ofwire, deformed snap hook, security of snap hookspring latch attachment, and loose or crackedswage fittings. If any damage is found, the pullcable is discarded and replaced with a new cable.The new cable is also tested. If the snap hook

spring latch is loose, it may be repaired inaccordance with instructions contained inNAVAIR 13-1-6.1.

If the pull cable passes this test, reinstall thecable. Refer to NAVAIR 13-1-6.1 for details ofinstallation.

LEAKAGE TESTING

The only way that you can be sure that a liferaft does not have a leak is to perform a leakagetest. To test the LRU-15/A with a vented Y-manifold for leakage, you must ensure that eitherthe manifold inlet is capped or an empty cylinderis installed and the manifold inlet is in theCLOSED position. Install an equalizer tubeclamp. These procedures are necessary for this raftdue to its design. The LRU-15/A has two flotationtubes; one is on top of the other. The equalizertube allows C02 or air pressure to enter both tubesat the same time. If you fail to cap the inlet, youwill not be able to hold the pressure within theflotation tube. If you don’t use an equalizerclamp, you will blow up both flotation tubes.

NOTE: Flotation tubes must be testedseparately to determine internal verticalbulkhead leakage.

All multiplace life rafts are filled with airpressure through the topping-off valves. The LR-1is inflated through an oral inflation tube.

After you have reached the test pressure (table6-1), shut off the air supply and wait 15 minutes.

Table 6-1.-Life Raft Test Pressures

6-3

Table 6-2.—Example of Temperature and BarometricPressure Check

.

Table 6-3.—Temperature Conversion Chart

After 15 minutes, adjust the air pressure ifnecessary. At this time you must record thetemperature and barometric pressure. This is donebecause any drop or rise in temperature orpressure affects the pressure within the flotationtube. Allow the raft to remain undisturbed fora minimum of 4 hours. At the end of 4 hours,check and record the test pressure and againrecord the temperature and barometric pressure.

See table 6-2 for an example. By using theconversion charts in tables 6-3 and 6-4, you candetermine the correct reading for your raft. Ifyour test pressure is within limits, you are readyto deflate the raft and repack the assembly. If theraft should fail this test, you must determine thecause. Information on testing for leaks can befound in chapter 2 of NAVAIR 13-1-6.1.

CLEANING

As you work on survival equipment you findthat cleanliness is very important. It gives theequipment a longer service life, and it reassuresthe aircrewman that he is using an operationalpiece of equipment. If he sees a dirty life raft, hemay think it is old and that it might leak. To cleanlife rafts, prepare a solution of cleaningcompound (MIL-C-25769) consisting of one partcompound and three parts water. Apply thecleaning solution to soiled area with a spray orsponge. Allow the solution to remain on thesurface for several minutes, then rub with a softbrush or rag. Rinse the surface thoroughly withwater and wipe with a cloth or sponge. Repeatthis application until the surface is free from allsolution. Dry the raft with a lint-free cloth, andapply a light coating of talcum powder.

HYDROSTATIC TEST OF CO2

CYLINDERS

Every 5 years you must hydrostatically test thecarbon dioxide cylinders used on multiplace liferafts. However, fully charged cylinders areconsidered serviceable regardless of the lasthydrostatic test date. If a cylinder is both due fora test and discharged, disconnect it from the raft.Obtain a new cylinder from supply as a re-placement. Forward the old cylinder to supply.(Cylinders must be empty before forwarding tosupply.) Before installing the new cylinder,perform the following tasks:

1.

2.

3.

4.

Gently tap the inverted cylinder with asmall piece of wood. If any rust or othercontamination falls from the cylinder, donot use it. Draw another from supply andrepeat the contamination check.Ensure that a siphon tube is installed onall multiplace life raft cylinders.Replace the stem in the inflation assemblyvalve.Install a new sealing washer. Refer toNAVAIR 13-1-6.1.

6-4

Table 6-4.—Barometric Pressure Conversion Chart

5. Thread thecylinder andof 600 ± 60

inflation valve onto thetighten it to a torque valueinch-pounds for multiplace

life raft cylinders and 400 ± 40 inch-pounds for LR-1 raft cylinders. T h ehydrostatic test does not apply to theLR-1 life raft cylinder.

MULTIPLACE RAFTS

Multiplace life rafts vary in size and in thequantity of equipment they carry.

CNO has established survival equipment listsas standards to be used by all concerned. Theselists provide the equipment necessary for aneffective 24-hour survival capability.

The body of the life raft consists of anencircling buoyant tube and a fabric bottom. Thefabric sections used in the inflatable buoyant tubeare incorporated in such a manner that the warpthreads of the straight fabric run in acircumferential direction around the tube, and thewarp threads of the bias cloth run in the oppositedirection in the adjoining sections.

The fabric bottom of the raft is appliedwithout tension across the enclosure formed by

the flotation tube, and it is attached securely tothe underside.

SEAM TAPES AND PATCHES

All raft seams and patches are secured by theuse of self-curing cement, applicable to thespecifications listed in the Inflatable SurvivalEquipment Manual, NAVAIR 13-1-6.1.

No sewing or stitches are used in the seamsor through the fabric of any compartment.However, sewing is permitted in the constructionof patches, oarlocks, disks, flap seats, cylindercarriers, lifeline supports, handles, and pockets.

Seam repair is done only if a flotation tubedoes not leak; that is, if only the outer seam tapeis loose or if the seam does not seal a flotationtube. If the seam tape is present and undamaged,recement the tape to the raft. If the tape is missing,measure and fit a replacement tape to the areaand cement it in place. Overlap the seam tape onother seams a minimum of 1 inch.

If the tape is damaged, peel the tape from theraft. Apply toluene only as needed to loosen thetape. Avoid excessive application of toluene onthe seams, and remove any spilled or excesstoluene immediately.

6-5

NOTE: Do not use toluene near openflame, heat, or electrical sparks. Avoidprolonged contact with the skin orbreathing the fumes. Use toluene only inwell ventilated areas.

Do not touch the cleaned raft areas whenhandling. Clean both the pieces to be cementedwith four applications of toluene. Apply thetoluene with back-and-forth strokes on the firstand third applications and one-waystrokes on thesecond and fourth. Allow the areas to dry betweenapplications.

Prepare cement and accelerator mixture.Prepare only enough mixture to last for 8 hours,as this is the effective active period for themixture. Dispose of any remaining mixture after8 hours.

Using a disposable brush, apply cement tocompletely cover surfaces to be cemented.

Apply two coats of cement to both pieces,allowing the first coat to dry for approximately10 minutes.

When the second coat of cement becomestacky, place the pieces together. If the cementedarea is a cut or tear, butt the edges of the damagedarea before applying a patch. Roll out the bubblesusing a wooden roller.

Allow the cemented area to dry for at least48 hours, and then dust the area with talcumpowder.

If the seam tape is only damaged, trim the oldtape and replace it with new tape. Overlap theother seam tape a minimum of 1 inch. All tapesand patches are applied to the life raft withouttension. The tape is applied in such away thatan equal amount of tape width is on each side ofthe seam edge, which it covers.

To patch a damaged area on a life raft, selectthe applicable color and type of raft cloth,depending on the type of raft to be repaired. Cuta rounded patch 1 inch larger than the damagedarea on all sides. Scallop the edges of the patchif it is larger than 5 inches in diameter.

If the damaged area in the floor is larger than1 inch, patches must be applied to both sides.Intermediate maintenance activities have the

prerogative to declare rafts beyond the capabilityof maintenance if internal patching is required.

Center the patch over the damaged area andtrace an outline of the patch on the raft fabric.

Cement the patch to the damaged area inaccordance with the instructions previouslydiscussed in this section. After all repairshave been made, perform a leakage test on theraft and dust the repaired area with talcumpowder.

BULKHEADS

The flotation tube is separated into twocompartments by internal vertical bulkheads.Bulkheads are constructed of laminated cloth andare of a six-gore hemispherical design. Thebulkheads are installed amidships, equidistantfrom the bow and stern so that the volume of thetwo compartments is equal. A 4-inch-diameterpatch of laminated cloth is securely cemented toeach side of the bulkhead, at the manifold, toprotect the bulkhead against abrasion by themanifold diffusers when the raft is packed in thecarrying case.

INFLATABLE SEATS

An inflatable seat is installed in certainmultiplace life rafts; for example, the LRU-12/A,LRU-13/A, and LRU-14 series. These seats arecircular and are made of laminated cloth. Theends of the seat are tailored to fit the curvatureof the flotation tube. The inflatable seat is anindependent air chamber and is manually inflatedthrough the topping-off valve by using the handpump provided. It is attached to the bottom ofthe raft with Y-shaped hinge tapes made oflaminated cloth. This method of attachmentallows for expansion and prevents undue stressesbetween the bottom of the raft and the seat.

SUPPLY POCKET

Each LRU-12/A, LRU-13/A, and LRU-14series life raft contains a supply pocket thatmeasures approximately 8 x 8 x 2 inches. Thepocket is attached to the starboard side of theflotation tube surface inside the raft by stitchingthe pocket to a patch and cementing the patch to

6-6

the tube. Using black washproof ink, ensure thateach pocket is clearly marked SUPPLY POCKETin 1/2-inch letters on the LRU-12/A andLRU-13/A rafts. The lettering should be l-inchhigh on the LRU-14 series supply pocket.

In addition to the starboard supply pocket, theLRU-14 series raft has a port supply pocket. Thispocket is attached to the raft in the same manneras previously discussed. The lettering height onthe port pocket is 1 inch for the first line and 1/4inch for all other lines.

COMBINATION SUPPLYPOCKET AND BAILER

Each life raft, except the LRU-15/A, containsone detachable combination supply pocket andbailer. The pocket is closed by means ofa slide fastener across the top, which issealed with tape after the equipment is packed.A loop of spring wire is contained in theseam around the slide fastener so that the pocketmay be fashioned into a bailing container. Oneend of a 5-foot length of type III nylon suspensionline is secured to the slide fastener wire stirruppull; the other end is attached to the nearestlifeline patch loop.

The words SUPPLIES AND BAILER arestenciled in 1/2-inch letters on the pocket. Belowthis, stenciled in 1/4-inch letters, are the pocketcontents.

The Supply and Bailer pocket on the STBDside of LRU-12/A, -13/A, and -14 series has beendeleted from newly procured rafts. New rafts arenot reworked to provide pocket and on older raftsthey need not be removed.

LIFELINE

A lifeline of natural color nylon rope,1/4-inch diameter, encircles the outboard per-imeter of the raft. The lifeline is attached to eachlifeline patch loop with an overhand knot tiedon the inner side of each patch loop so asto prevent the line from running free throughthe loops. Four inches of slack is allowed inthe line between the lifeline patch loops. Eachcompleted lifeline patch can withstand a 250-pound pull exerted in a direction perpendicularto the base of the patch.

The lifeline provides a means for secur-ing the accessory containers to the life raftby using a 10-foot length of type 111 nyloncord.

The LRU-15/A life raft also has an innerlifeline that provides for the safety and survivalof aircrewmen.

RIGHTING HANDLES

Righting handles are provided on all liferafts except the LRU-15/A. These handlesprovide a means of righting a capsizedraft.

TOPPING-OFF

Topping-offflotation tube,

VALVES

valves are installed on eachinflatable seat, each section

of inflatable floors, and each side of thefloor supports. The required number of top-ping-off valves and their location on therafts may vary depending on the type of raftconcerned.

Topping-off valves are used for manualinflation purposes in conjunction with thehand pump. The valve also serves as ameans for relieving high internal tube pres-sure that may possibly build up during hot, sunnydays.

Two topping-off valves are installed on thesame side of the raft’s main flotation tube—oneon each side of the internal bulkhead—above theinside horizontal centerline of the tube, 4 inchesfrom the point of attachment of the verticalinternal bulkhead.

Stenciled instructions relative to topping-offand deflation of the raft are applied on theraft flotation tube adjacent to the topping-offvalves. Appearing in 1/4-inch, washproof blackink letters, the instructions are stenciled on awhite rubber patch as follows:

T O I N F L A T E C O M P A R T M E N T SMANUALLY: Attach hand pump tovalve cap, unscrew cap 1 1/2 turns tothe right and then pump to inflate.When desired pressure is attained, re-tighten valve cap and remove pump.

6-7

TO DECREASE PRESSURE: Open valve1 1/2 turns to the right and bleed.

INFLATION SYSTEM

The valve of the CO2 cylinder is threaded intothe coupling nut of the manifold. Since multiplacelife rafts are constructed with internal bulkheads,the purpose of the manifold is to provide a com-mon means of directing and diffusing the flowof carbon dioxide entering the raft’s inflatabletube chamber. The manifold outlets must bridgethe internal bulkhead over which they aremounted. Figure 6-1 illustrates the operation ofthe raft’s CO2 inflation system manifold.

All of the exposed metal surfaces of theinflation system that might chafe the raft fabricwhile packed must be covered with several layersof rubber-coated cloth, and secured with cloth-based, pressure-sensitive tape.

Because of space limitation, this chaptercannot possibly contain all of the availableinformation concerning life rafts. The InflatableSurvival Equipment Manual, NAVAIR 13-1-6.1,is referenced for more detailed information.

239.338Figure 6-1.—Multiplace raft CO2 inflation system

manifold operation.

6-8

LRU-12/A LIFE RAFT ASSEMBLY

The LRU-12/A life raft assembly consistsof an inflation assembly (carbon dioxidecylinder and inflation valve) and a four-manraft. Two types of carbon dioxide cylinders andfour types of inflation valves are approved forservice use. The life raft is made up of a two-compartment main tube; an inflatable seat at-tached to the main tube; a noninf’latable floorattached to the bottom of the main tube andinflatable seat; and a sea anchor, which is usedto retard drifting. A lifeline, a righting line, asupply pocket, and a combination supply pocketand bailer are attached to the main tube.

Boarding and righting handles are attached tothe main tube and the floor. Emergency survivalequipment and raft accessories, stowed inaccessory containers, are provided for the safetyand survival of the aircrewmen. The lifeline alsoprovides a means for securing the accessorycontainers to the life raft. Topping-off valves arelocated on the main tube and inflatable seat. AnLRU-12/A life raft is shown in figure 6-2.

NOTE: To makeup the packaged life raftassembly complete with accessories andsurvival items, all required components notsupplied with the raft assembly must beindividually requisitioned.

The LRU-12/A life raft assembly (droppable)is inflated by pulling the inflation assemblyactuating handle, located under the carryingcase end flap. The LRU-12/A life raft as-sembly (raft compartment installation) is auto-matically inflated and ejected after the raftcompartment door has been released. Afterboarding, the inflatable seat should be in-flated through the topping-off valves withthe hand pump provided in the accessorycontainer.

The LRU-12/A life raft assembly can eitherbe dropped to survivors or used by aircrewmenin the event of an aircraft ditching emergency. Theraft is stowed in a readily accessible area insidethe aircraft fuselage on all applicable aircraftexcept the S-2 series.

Prior to packing any life raft, the assemblymust be updated by comparing the configurationof the assembly with the modifications listed inthe applicable chapter in NAVAIR 13-1-6.1.

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Survival items are intended to provide ameans for sustaining life, aiding in escape andevasion, and for a suitable detection capability.Survival items may be packed in life rafts,droppable kits, kits intended to be carried or wornby the aircrewmen, or they may be individuallycarried.

The equipment and survival items car-ried in the LRU-12/A life raft assemblydiffer from that carried in other rafts basi-cally in the quantity carried, with a fewminor exceptions. Table 6-5 lists the survivalitem requirements and the applicable itemstorage container and pocket for LRU-12/A,LRU-13/A, LRU-14 series, and LRU-15/A liferafts.

LRU-13/A LIFE RAFT ASSEMBLY

The LRU-13/A life raft assembly consistsof an inflation assembly (carbon dioxidecylinder and inflation valve) and a seven-man raft. Two types of carbon dioxide cyl-inders and four types of inflation valvesare approved for service use. The life raftis made up of a two-compartment main tube;an inflatable seat attached to the main tube;a noninflatable floor attached to the bot-tom of the main tube and inflatable seat;and a sea anchor, which is used to retarddrifting. A lifeline, a righting line, a sup-ply pocket, and a combination supply bagand bailer are attached to the main tube.Boarding and righting handles are attachedto the main tube and the floor. Emergencysurvival equipment and raft accessories arestowed in the accessory containers. The life-line also provides a means for securing theaccessory containers to the life raft. Top-ping-off valves are located on the main tubeand the main seat. The LRU-13/A liferaft assembly and parts nomenclature arethe same as the LRU-12/A (shown in figure 6-2),except that the LRU-13/A is longer.

EQUIPMENT AND SURVIVAL ITEMS

The LRU-13/A life raft equipment andsurvival item requirements and the applica-ble storage container are listed in table6-5.

PACKING PROCEDURES REMOTEOR LOCAL PULL

Prior to packing the LRU-13/A life raftassembly, it must be updated by comparing theconfiguration of the assembly with themodifications listed in NAVAIR 13-1-6.1.

The LRU-13/A life raft assembly may bepacked for droppable inflation, or for installa-tion into the aircraft nacelle or raft compart-ment. The method used for packing depends uponthe aircraft application.

NOTE: The inflation cable housingmust not be inserted through the abra-sion patch sleeve when folding and pack-ing the raft. The cable housing should beinserted into the sleeve after the raft isinflated.

Here are the packing procedures for theLRU-13/A life raft assembly. These packingprocedures apply to all methods of packing unlessa specific method for either the droppable or localmode of inflation is specified in parentheses.

1. Ensure that the raft, carrying case, andaccessory container have been inspected.

2. Ensure that the survival items and raftaccessories have been inspected for expiration anddamage. Refer to table 6-5 for items used.

3. Wrap all sharp or pointed metallicaccessories and survival items with rubber-coatedcloth, and secure the objects with rubber bands.Stow the accessories and survival items in theaccessory container, or the supplies and bailerpocket, as applicable.

4. Cover the inflation valve with several layersof rubber-coated cloth, and secure it with cloth-based, pressure-sensitive tape. Take the webbingretaining line, righting line, and sea anchormooring line and secure them with rubber bands.Ensure that all of the topping-off valves are closedand the raft is

5. Using acord, tie theto the nearestC O2 cylinder,the raft.

completely deflated.

10-foot length of type III nylonaccessory equipment containerlifeline loop located next to theand stow the container inside

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Table 6-5.—Life Raft Survival Item Requirements and Item Storage Containers for LRU-12/A, LRU-13/A, LRU-14 Series.and LRU-15/A Life Rafts

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Figure 6-3.—LRU-l3/A raft-folding procedures (droppable).

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6. (Fold the raft in accordance with figure6-3, for droppable inflation).

7. Insert the folded raft into the carryingcase so that the actuating handle or pull cablehousing is positioned under the carrying case endflap.

8. Secure the carrying case snap fasteners.

NOTE: If the actuator case snap hookis not soldered, wrap tape around thehook to prevent possible loss of the springlatch.

9. Rig the pull cable housing to the carryingcase ripcord.

10. (Install the ripcord and safety tiethe first and last ripcord pins by passing a12-inch length of size E nylon thread underthe ripcord pin). Secure the thread to the rip-cord cable with three or four half-hitches(fig. 6-4).

NOTE: Rafts stowed inboard on aircraftare secured to the aircraft with a painterline. The painter line is a 60-foot lengthof cotton cord (unless otherwise specifiedby the applicable aircraft MIM), type I,size 4, with a 50- to 150-pound staticbreaking strength.

The painter line retains the deployed raftto the aircraft, but will easily break if theaircraft sinks. The painter line is attached tothe sea anchor mooring patch loop unlessotherwise specified by the applicable aircraftMIM. Stow the painter in the painter line pouch,and place the pouch under the packed raft ifpossible.

Figure 6-4.—Safety tying ripcord.

11. (Snap the ripcord protector flap closed,position the ripcord handle under the carryingcase end flap, and snap the end flap closed).

12. (Ensure that the inflation valve actuat-ing handle is positioned outside the carryingcase end flap, and snap the end flap closed).

When the LRU-13/A life raft assembly ispacked for installation into the aircraft nacelle orraft compartment, follow procedures outlined inthe applicable aircraft MIM.

All LRU-13/A life raft assemblies installedin C-1 aircraft must be packed for down-pull inflation using the “snap hook” remoteactuator assembly, which consists of a snaphook pull cable assembly and a pull cablehousing assembly. In no instance should“ice-tong” remote actuator assemblies be usedin C-1 aircraft.

LRU-14 SERIES LIFERAFT ASSEMBLY

The LRU-14 series life raft assembly con-sists of an inflation assembly (carbon dioxidecylinder and inflation valve) and a 12-manraft. Two types of carbon dioxide cylinders andtwo types of inflation valves are approved forservice use.

The life raft is made up of a two-com-partment main tube; a smaller single-com-partment upper tube, which is permanentlyattached to the top of the main tube; aninflatable seat attached to the main tube; anoninflatable floor attached to the bottomof the main tube and seat; a two-sectioninflatable floor tied to the inside of the non-inflatable floor; and a sea anchor, which is usedto retard drifting.

A lifeline and a supply pocket are attached tothe main tube. Boarding and righting handles areattached to the main tube and both floors.Survival equipment and raft accessories, stowedin the accessory container, provide for the safetyand survival of the aircrewmen. The lifeline alsoprovides a means for securing the accessorycontainers to the raft. Topping-off valves arelocated on the upper tube, inflatable seat, and onboth sections of the inflatable floor. The LRU-14

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239.347.1Figure 6-5.—LRU-14 series life raft assembly, parts nomenclature.

series life raft assembly parts nomenclature is sufficient equipment and items for 24-hourshown in figure 6-5. survival.

EQUIPMENT AND SURVIVAL ITEMS The LRU-14 series life raft equipment,CNO has established survival equipment lists survival item requirements, and the applicable

as standards for all concerned. These lists provide storage container are listed in table 6-5.

6-14

NOTE: To make up the package life raftassembly complete with accessories andsurvival items, all required components notsupplied with the raft assembly must beindividually requisitioned.

OPERATION

The LRU-14 series life raft assembly is in-flated by pulling the inflation assembly actuat-ing handle, located under the carrying case endflap. The inflation assembly inflates the maintube only. After the survivor boards the raft, theupper tube, seat, and floor sections should be in-flated through the topping-off valves, with thehand pump provided in the accessory container.

The LRU-14 series life raft assembly can eitherbe dropped to survivors or used by aircrewmenin the event of an emergency. The raft is stowedeither in a readily accessible area inside the aircraft

fuselage or in an aircraft compartment designedfor rafts.

Prior to packing, the LRU-14 series life raftassembly should be updated with themodifications listed in NAVAIR 13-1-6.1.

The LRU-14 series life raft assembly maybepacked for droppable or aircraft installation. Themethod used depends upon aircraft application(fig. 6-6).

LRU-15/A LIFE RAFT ASSEMBLY

The LRU-15/A life raft assembly consists ofan inflation assembly (carbon dioxide cylinder,inflation valve, and cover) and a 20-man liferaft.

The life raft is made up of two single-compartment circular tubes connected by anequilizer tube; a noninflatable floor suspended

239.345Figure 6-6.—LRU-14 series folding procedures (droppable).

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between the circular tubes; and a boarding ramppermanently attached to each circular tube. Thefloor is equipped with a built-in inflatable floorsupport, and the inflatable boarding ramps arelocated on opposite sides of the raft.

A sea anchor, used to retard drifting, is stowedin the sea anchor pocket, which is located at thejunction of the circular tubes. An inner lifeline,boarding handles, a heaving line, and emergencysurvival equipment, stowed in the accessorycontainer, are provided for the safety and survivalof the aircrewmen. The inner lifeline, attached tothe floor, and the boarding handles, attached tothe circular tubes and boarding ramps, are usedto secure the accessory container to the raft.Topping-off valves are located on each side of thetubes. A topping-off valve is also located on eachside of the floor support. The LRU-15/A life raftassembly parts and nomenclature are shown infigure 6-7.

EQUIPMENT AND SURVIVAL ITEMS

The LRU-15/A life raft equipment andsurvival item requirements and the applicablestorage container are listed in table 6-5.

The LRU-15/A life raft assembly (droppable)is inflated by pulling the inflation assemblyhandle, located under the carrying case end flap.

The LRU-15/A life raft assembly (winginstallation) is automatically inflated and ejectedfrom the raft compartment after the life raftcompartment door has been released. A uniquedesign feature of the LRU-15/A is that it is alwaysright side up after inflation. The inflationassembly inflates the circular tubes and boardingramps only. In the event that the inflationassembly does not function properly, the equalizertube distributes gas equally between eachcircular tube. After boarding, the floor sup-port is inflated with the hand pump provided inthe accessory container. The circular tubes maybe topped off, if necessary, from either side ofthe raft floor.

The LRU-15/A life raft assembly can be eitherdropped to survivors or used by aircrewmen inthe event of an emergency. Each type of packagedLRU-15/A life raft assembly is used in certaintypes of aircraft; for applicable configurations,refer to the aircraft MIM.

Prior to packing the LRU-15/A life raftassembly, it must be updated by comparing theconfiguration of the assembly with themodifications listed in NAVAIR 13-1-6.1.

EMERGENCY REPAIRS

Emergency repair of the LRU-15/A raft, whenin the water, is accomplished by the use of themetal clamp type plugs provided in the accessoryequipment container of each raft. No emergencyrepair equipment is provided with other types ofrafts.

DEMONSTRATING THE USEOF RAFTS

Many ditching and water crashes occur in arough sea or at n ight . Only completefamiliarization with the use of survival equipmentwill give the aircrewman a chance of survivalunder such adverse conditions. Therefore,intensive drill in the use of rafts and theirassociated equipment is essential for safety.

The survival officer must be concerned withsurvival techniques and should see that a survivaltraining program is set up in the parachute loft.In most cases, the chief in charge of the loft hasthe responsibility of setting up this training. Asa PR2 you will have many occasions to participatein this training and, in many instances, may becompletely responsible for the carrying out of theprogram. Regardless of who is in charge and mustshoulder the complete responsibility, it is the dutyof every PR to be completely familiar with allphases of survival training and to be able todemonstrate the use of survival equipment.

The multiplace egress trainer is a very effectivesystem of training in water survival techniques.It is used to simulate an actual aircraft ditching,and to teach the best escape procedure with fullequipment.

Although such complete courses of trainingcannot be conducted in certain localities becauseof the lack of specialized equipment, the PRshould make every attempt to give aircrewmenfrequent practice in the actual use of theequipment. Discussions, demonstrations, andshop lectures are all helpful, but working with theactual raft equipment is the only way to acquirethe knowledge essential to survival.

In demonstrating the raft’s use, the mostimportant thing to stress is that the retainerlanyard snap is firmly attached to the ring on thelife vest before inflating the raft. Inflate the raftas soon as possible so that personnel can get outof the water. The raft is inflated by pulling onthe short length cable attached to the C02 cylindervalve. After several hours, the CO2 cylinder maybe removed from the side of the raft. It tends to

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239.347Figure 6-7.—LRU-15/A life raft assembly, parts nomenclature.

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chafe the side of the compartment and acts as ananchor, causing the raft to orbit around it.Sometimes it is possible to back off the couplingbetween the cylinder and the manifold so that thecylinder releases from the mount. Once thecylinder has been removed, it is no longer usefulin any way and should be thrown over the side.This, of course, is under actual emergencyconditions; in a training demonstration, thecylinder should be saved and recharged for furtheruse on the training equipment.

In demonstrating their use, also giveinstructions on manual inflation of rafts. Ifnothing happens after the CO2 cable has beenpulled, the carrying case should be pulled off andthe raft unfolded so that the hand pump will beaccessible. After the pump is removed, the firstcompartment to be inflated should be the seat.This will help keep the raft afloat so that theremaining compartment can be inflated with thepump. In attaching the pump, care must be takennot to screw the pump too tightly to the valve.If it is too tight, it may freeze and becomeimpossible to loosen without some type of wrenchor pliers.

BOARDING THE RAFT

The best method for boarding the multiplacelife raft is to use the boarding stirrup located onthe stem of the LRU-12/A, -13/A, and -14 series.This stirrup will allow the aircrewman to boardthe raft from the stern; boarding from the sternwill lessen the possibility y of capsizing the raft (fig.6-8).

If the raft should capsize, it is best to approachit from the side on which the CO2 cylinder is in-stalled. The survivor reaches across the raft andgrasps the righting handle farthest from the cylin-der. Then, by sliding back into the water and pull-ing on the righting handle at the same time, theraft will turn right side up. By using this method,there will be no chance of the CO2 cylinder hittingthe survivor when he rights the raft (fig. 6-9).

Another important point to remember in right-ing the raft is to note the wind and take advantageof it. It is very hard to right a raft against thewind.

SAFETY PRECAUTIONS INBOARDING RAFTS

Extreme care should be taken when boardingrafts or assisting personnel into the raft from thewater. This is particularly so if these persons arewearing parachute harness or life vests. Once in

Figure 6-8.—Boarding the239.355

LR-1 raft.

the raft, all personnel should seat themselves onthe floor and remain in that position if at all possi-ble. Movement within the raft should be restrictedas much as possible to keep friction at a minimum.All sharp objects should be collected andstored, especially jeweled rings, wristwatches, etc.

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239.356Figure 6-9.—Righting a capsized raft.

All loose articles of equipment should be properlypackaged to protect the raft fabric.

ONE-MAN LIFE RAFTS

One-man life rafts are used with various softand hard types of survival kits. They are intendedfor use by aircrew members forced down at sea.They can also be used when forced down overland for fording rivers and streams, or as a shelter.

LRU-7/P LIFE RAFT ASSEMBLY

The LRU-7/P consists of a simplified one-man life raft, a static line release mechanism, anda special container with tabs for attachment tothe parachute and seat pan. Although simplifiedin its construction, the LRU-7/P is comparableto the standard Navy one-man life raft except itcontains no survival items (fig. 6-10). The

239.351.1Figure 6-10.—LRU-7/P life raft assembly, parts nomenclature.

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LRU-7/P is used with a modified SP-1A seatpan and NS-3 and NES-21A parachutes.

LR-1 LIFE RAFT ASSEMBLY

The LR-1 life raft assembly consists of aninflation assembly (carbon dioxide cylinder andinflation valve) and a one-man life raft; threetypes of carbon dioxide cylinders and three typesof inflation valves are approved for service use.

The raft consists of a single-compartmentflotation tube with a noninflatable floor. It isblue (when initially procured) and features aweathershield, sea anchor, sea anchor pocket, anda retaining line pocket. The weathershield is a dullsea-blue color on the outside and a bright red onthe inside. In addition, a directive compliancepatch and an inspection record patch are includedfor record keeping. The various applications ofthe LR-1 life raft are contained in NAVAIR13-1-6.1.

Emergency survival equipment (when used) issecured to the raft by either a securing line or adrop line, as applicable. The packagedconfiguration of an LR-1 life raft assembly,including survival items, varies according toapplication.

To makeup a packaged assembly, the requiredcomponents must be individually requisitioned,unless otherwise specified.

The LR-1 life raft assembly is inflated eithermanually by pulling the inflation assemblyactuating lanyard, or automatically on the LR-1(RSSK) by gravity drop on the kit actuation. Theinflation assembly inflates the flotation tube.After boarding the raft, you can top off the LR-1by using the oral inflation valve.

This section describes the components of theLR-1, the survival equipment, and the proceduresfor performing inspections and maintenance. Wewill not repeat procedures that parallel thosealready outlined for multiplace rafts.

Flotation Tube

The body of the raft consists of an encirclingtube, which is one continuous chamber. There areno internal bulkheads as in the multiplace rafts.Various attachments to the flotation tube areshown in figure 6-11.

Oral Inflation Tube

The valve on the oral inflation tube closesautomatically by spring pressure when it is notheld open. The valve is locked shut by turning the

239.351Figure 6-11.—LR-1 life raft assembly.

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mouthpiece in a clockwise direction. The 3/8-inch oral inflation tube is cemented to the valve at oneend, and at the other end, it has a molded flangethat is cemented to the flotation tube.

Boarding Handles

Five handles are provided as aids for boardingthe raft.

Ballast Bags

Ballast bags, installed at two locations, arerequired to increase the raft stability, to preventthe raft from becoming airborne during helicopterpickup, and to aid in boarding the raft.

Weathershield

The weathershield is used to protect thesurvivor from adverse weather.

Sea Anchor

The sea anchor is used to keep the inflated raftfrom drifting. The sea anchor is tied to the raftmooring line with type III nylon line, using abowline knot; the other end is tied to the seaanchor mooring patch with a bowline knot. Thebitter ends of both knots are seared and completedwith an overhand knot to prevent them fromuntying. Before tying the knots, the ends of thenylon line are heat fused to prevent fraying.

Sea Anchor Pocket

The purpose of the sea anchor pocket is toprevent survivors from getting tangled up in thesea anchor line while boarding the raft. Downedaircrewmen should remove the sea anchor fromthe pocket and cast the anchor adrift immediatelyafter boarding the raft.

Securing Line

The securing line is 5 feet of nylon cord. Itsecures the raft to the raft container, to preventloss of the survival items.

The nylon cord is inserted through thewebbing loop on the sea anchor mooring patchand secured with a bowline knot, followed by anoverhand knot. The free end is secured to the raftcontainer during the raft packing.

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Retaining Line

A nylon webbing retaining line 1 inch wide and6 1/2 feet long is used to secure the raft to theuser. One end of the retaining line is equippedwith a snap hook. The other end is secured to theC O2 cylinder neck by passing the end of theretaining line with the loop formed in it aroundthe coupling nut between the raft and the infla-tion assembly. The end of the line containing thesnap hook is then passed through the loop andpulled up tight.

Survival Items

The LR-1 packaged assemblies requiringsurvival items are equipped with the items listedin table 6-6. These items are packed in either the

Table 6-6.—LR-1 Life Raft Survival Items

combination carrying case and equipment con-tainer or in the equipment container, as ap-plicable. The remaining space in the containermay be used for any specialized equipment forspecific environmental or geographic conditions,as directed by the area commander.

You should refer to NAVAIR 13-1-6.1 forinformation concerning which type of packagedLR-1 life raft assembly is used aboard certaintypes of aircraft.

Inspection

During the life raft inspection phase and priorto starting any packing procedures, the life raftmust be updated and modifications incorporatedif required. Compare the life raft assemblyconfiguration with the applicable raft modi-fications listed in NAVAIR 13-1-6.1.

All life raft assemblies get a calendar in-spection upon issue and at intervals that coincidewith the aircraft inspection cycle. However, theinterval between calendar inspections must notexceed 231 days.

The procedure for inspecting and testing thelife raft is generally the same as those given earlierin this chapter for the multiplace life raft.Additionally, you should read NAVAIR 13-1-6.1.Where there are considerable differences in raftconstruction, certain steps may be eliminated oradded as necessary. For example, life rafts are notconstructed with internal bulkheads. Since thereis only one continuous flotation tube, the in-ternal bulkhead test is not necessary on the liferaft. The life raft is fitted with an oralinflation tube, but it serves the same purposeas the multiplace raft topping-off valves.Therefore, the same general considerationsgiven the topping-off valve should be appliedto the oral inflation tube. For instance, althoughthe exposed end of the oral inflation tubehas no rough edges, it is kept in a supportingpocket.

LIFE PRESERVERS

Life preservers are worn by aircrew memberson overwater flights. Their function is to keepthem afloat until a raft can be reached or untila rescue team arrives. Proper inspection, mainte-nance, and handling of life preservers arenecessary to prevent any possible malfunction thatcould result in the loss of life.

LPU-21/P SERIES LIFEPRESERVER ASSEMBLY

The LPU-21/P series life preserver assemblyis authorized for use by all aircrew personnelwearing compatible flight clothing. It is designedas a constant wear item for use with the survivalvest and will not interfere with the removal of thenonintegrated parachute harness. Survival itempouches are attached to the life preserver casing.The dye marker and signal flares that go intothese pouches are not initially supplied andmust be individually requisitioned. Modifica-tions to the LPU-21/P life preserver have re-sulted in a new letter designation being assignedto the preserver. For the sake of clarity, the termLPU-21/P series is used where appropriate.

WARNING

THE LPU-21/P SERIES LIFE PRE-SERVER ASSEMBLIES ARE NOTUSED IN EJECTION SEAT AIR-CRAFT.

NOTE: The LPU-21B/Pand LPU-21C/P life pre-server assemblies must NOTbe configured with theFLU-8A/P automatic in-flation device.

The LPU-21/P and LPU-21A/P life preserverassemblies use pull toggles for activation. Afterthe incorporation of Aircrew System Change 405,which directs installation of beaded inflationhandles, the LPU-21/P and LPU-21A/P wereupdated to become the LPU-21B/P. The beadedinflation handles improve toggle accessibility andprovide the inflation system with a multi-directional pull capability.

The LPU-21/P series life preserver assemblyweighs 4 pounds (without survival items) andprovides a minimum of 65 pounds of buoyancy.The flotation assembly is constructed ofpolychloroprene-coated nylon cloth and consistsof two independent flotation chambers. Onechamber consists of the left waist lobe joined bya tube to the right collar lobe. This chamber isserviced by the carbon dioxide inflation assemblyand oral inflation valve attached to the left waistlobe. The other chamber consists of the right waistlobe joined by a tube to the left collar lobe. Thischamber is serviced by the carbon dioxideinflation assembly and oral inflation valveattached to the right waist lobe. The two chambersare sewn together at the collar lobes (fig. 6-12).

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239.468Figure 6-12.—LPU-21/P series life preserver assembly, parts nomenclature.

6-23

Each waist lobe of the flotation assembly isequipped with an attachment patch used forsecuring the casing assembly by means of rivets.In addition, the right waist lobe is equipped withone snap hook and the left waist lobe is equippedwith one D-ring. The snap hook and the D-ringare used to secure the waist lobes together afterinflation. Survival item pouches are fastened tothe life preserver D-rings with directional snapfasteners.

Each collar lobe of the flotation assembly isequipped with a snap hook for attachment to thesurvival vest D-rings (parachute risers are routedoutside of the collar lobes). In addition, aninspection record patch is also provided on a collarlobe.

The casing assembly is constructed of fire-retardant Aramid cloth and protects the flotationassembly. The casing assembly also provides forsize adjustment and attachment to the wearer. Thecasing assembly consists of the adjustable casing,an adjustable webbing belt, belt keepers and D-rings, and the front connector assembly.

The webbing belt, attached to the inside waistportion of the casing assembly, provides for waistsize adjustment from 30 to 44 inches. The webbingbelt keeper loops retain the webbing belt andprovide for attachment of the survival vest aboutthe wearer’s waist. In addition, there are six D-rings secured to the webbing belt keeper loops,used for attaching the survival item pouches, araft retaining line, and other accessories.

Hook and pile tapes, attached to the outsidewaist portion of the casing, are used for slackadjustment. In addition, hook and pile tapes,attached about the circumference of the collarcasing and the lower edge of the back portion ofthe casing, are used to enclose the casing assemblyabout the flotation lobes.

The casing assembly is secured around thewearer’s waist by the front connector assembly,which. consists of two snap hooks and two D-ringsbacked by webbing pads for comfort.

Each inflation assembly is made up of acarbon dioxide cylinder and an inflation valve.The inflation assemblies are connected to valvestems attached to each waist lobe (each valve stemis equipped with a check valve to prevent leakage).

As stated earlier, the LPU-21/P series lifepreserver assembly is authorized for use by allaircrew personnel wearing compatible flightclothing. LPU-21 /P series life preservers that aremodified to incorporate the FLU-8/P seriesautomatic inflation device will be used in ejectionseat type of aircraft only. LPU-21/P series life

preservers modified with the FLU-8A/P inflatorwill be redesignated the LPU-23A/P life pre-server.

The LPU-21/P series is manually inflated bypulling both inflation assembly beaded handlesin a natural, slightly down and straight outposition from the body. This action removes theretaining pins securing the casing assembly aboutthe waist lobes and actuates the inflationassemblies. The hook and pile tapes securing thecasing assembly about the collar lobes willseparate as the preserver inflates.

NOTE: The casing must be manuallyopened and the flotation assemblyunfolded prior to inflating a preserverthrough the oral inflation valve.

In an emergency situation, the oral inflationvalves may be used to top off an inflatedpreserver, maintain inflation of a leaky preserver,or inflate a chamber if an inflation assemblymalfunctions. The oral inflation valves are alsoused to inflate a preserver with air during aninspection test and to evacuate a preserver inpreparation for packing.

LPU-23/P SERIES LIFEPRESERVER ASSEMBLY

The LPU-23/P series life preserver assembliescontain an automatic inflator that is intended foruse by an aircrew member in an ejection seataircraft ONLY.

The LPU-23/P assembly is identical to theLPU-21/P assembly except for the FLU-8A/Pautomatic inflation device (fig. 6-13).

The LPU-23/P series life preserver assemblyis inflated either automatically (by immersion infresh or salt water) or manually (by pulling bothinflation assembly beaded handles).

NOTE: The primary means of inflation isto manually pull the beaded handles.

Automatic inflation occurs when immersionin water triggers the electronic circuit, firing theexplosive primer. The high-pressure primer forcesthe piecing pin forward, releasing the inner endof the packing cord loop and puncturing the35-gram CO 2 cylinder, which releases thepressurized gas. Automatic inflation is a onetimefunction of the FLU-8A/P inflator. A newinflator must be installed to replace the previouslyspent device. Manual inflation occurs when both

6-24

Figure 6-13.—LPU-23/P series life preserver assembly, parts nomenclature.

6-25

beaded inflation handles are pulled in a natural,slightly down and straight out position from thebody. The FLU-8A/P inflator may be operatedmanually an unlimited number of times withoutaffecting the onetime automatic feature.

LPU-24/P SERIES LIFEPRESERVER ASSEMBLY

The LPU-24/P life preserver assembly isidentical to the LPU-23/P life preserver assemblyexcept for the fabrication of the casing assembly.The LPU-24/P has a casing assembly that isconstructed from rubber-coated nylon clothinstead of Aramid, fire-resistant fabric like theLPU-21/P and the LPU-23/P series life pre-servers. The LPU-24/P life preserver is notcovered in this chapter.

LPP-1/1A LIFEPRESERVER ASSEMBLY

The LPP-1/1A life preserver assembly isauthorized for use by passengers in cargo ortransport type of aircraft for sea survivalsituations.

WARNING

THE LPP-1/1A LIFE PRESERVER ISNOT SUITABLE FOR USE BY SMALLCHILDREN IN NAVAL AIRCRAFT.

The LPP-1 and LPP-1A life preserver as-semblies are identical with the exception of themechanical inflation assembly.

The LPP-1/1A life preserver assembly (fig.6-14) weighs approximately 3 pounds and providesa minimum of 29 pounds of buoyancy. TheLPP-1/1A life preserver assembly consists of asingle-compartment yoke-type flotation assem-bly, a pouch and belt assembly, an inflationassembly, and a storage container. Survivalitems are also provided. To make up theLPP-1/1A life preserver assembly, all re-quired components not supplied with the preservermust be individually requisitioned.

The flotation assembly is constructed ofchloroprene-coated nylon cloth. It is equippedwith an oral inflation valve, a valve stem, survivorlocator light attachments, a whistle pocket, a beltloop, and an inspection record patch (fig. 6-14).

The pouch and belt assembly consists of arubber-coated nylon cloth pouch and anadjustable belt. The pouch contains the flotationassembly and survival items. The belt consists ofa 53-inch piece of webbing, an adjustable buckleand clasp, a toggle assembly, and a toggleassembly pocket. The belt adjusts from a waistsize of 30 to 52 inches and attaches the flotationassembly and pouch to the wearer by means ofthe belt loop on the flotation assembly and theslots in the back of the pouch. The toggleassembly consists of a wooden toggle and line,and is used to secure survivors together while theyare in the water. When not in use, the toggle lineis wrapped around the wooden toggle and stowedin a pocket located on the belt (fig. 6-14).

NOTE: The carbon dioxide cylinder isNOT supplied with the preserver assemblyand must be requisitioned separately.

The LPP-1 inflation assembly consists of aType I (MIL-C-25369), 25- to 28-gram carbondioxide cylinder and an inflation valve. TheLPP-1A inflation assembly consists of a Type II(MIL-C-25369), 28- to 31-gram carbon dioxidecylinder and an inflation valve (MIL-I-23145).The inflation assembly is connected to thevalve stem on the front of the flotation assem-bly. The valve stem is equipped with a checkvalve, which prevents leakage.

The storage container is used to store the lifepreserver assembly when it is not in use. Thestorage container also has donning instructionsprinted on it.

As LPP-1/1A life preservers becomeavailable, the use of all other life preservers bypersonnel authorized to use the LPP-1/1A willbe discontinued. Passengers whose total clothingand equipment weight does not exceed 15 poundsand who are not carrying any high density itemslike weapons or other similar metallic items areauthorized to continue use of MK-2 life preserver,with attritional basis method for replacement withLPP-1/1A.

LPU-30/P LIFEPRESERVER ASSEMBLY

The LPU-30/P life preserver assembly is avest-type preserver (cardigan style, sleeveless) thatweighs approximately 3 pounds (without survivalitems) and provides a minimum of 29 pounds ofbuoyancy. The preserver consists of a single-compartment flotation assembly, a fully lined

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Figure 6-14.—LPP-l/A life preserver assembly.

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protective cover with nondirectional front closuresnaps, side buckle adjustments, and inflationassembly. Survival items are also provided. Tomake up the LPU-30/P life preserver assembly,all required components and survival items mustbe individually requisitioned (fig. 6-15).

The flotation assembly is constructed ofpolyurethane-coated nylon cloth and is availablein one size. It is equipped with an oral inflationvalve and tube, a pressure relief valve to preventover inflation, a brass manifold for attachmentof the inflator, a l-inch piece of hook tape securedto the left front portion of the bladder, and anantichafing pad sewn to the inside neck area onthe bladder.

The protective cover is fabricated of whitecotton balloon cloth (MIL-C-332) and is availablein medium (chest up to 48 inches, & 1/2 inch) andlarge (chest up to 53 inches, ± 1/2 inch). Thecover has nondirectional front closure snaps andside buckle waist adjustments and is fully lined.There is also a strip of reflective tape sewn acrosseach shoulder and a strobe light pouch, whichmust be sewn to the upper breast portion of theprotective cover, and a sea dye marker pouch,which must be sewn to the lower left portion ofthe protective cover.

The inflation assembly consists of two TypeII (MIL-C-601), 12-gram CO2 cylinders and aType III (MIL-I-23145) inflation valve. Theinflation assembly is connected to the valve stemlocated on the right front of the flotationassembly. The valve stem is equipped with a checkvalve to prevent leakage.

The LPU-30/P is manually inflated by pull-ing the inflation assembly lanyard down. In anemergency situation, the oral inflation valve isused to top off an inflated preserver, maintaininflation of a leaky preserver, or inflate apreserver when the inflation assemblymalfunctions or fails. The oral inflation valve isalso used to inflate a preserver with air during aninspection test and to deflate a preserver inpreparation for issue.

The LPU-30/P life preserver is used bypassengers in all helicopters and in the C-1, C-2,and US-3A type aircraft. The LPU-30/P must notbe confused with the MK-1 flight deck lifepreserver. Information on the MK-1 preserver canbe obtained by contacting Naval Sea SupportCenter Pacific, P.O. Box 85548, San Diego, CA92138-5548, ATTN: Code 914. Request MIPH-402/2-47.

LIFE PRESERVER INSPECTIONS

All life preservers need to have preflight,special, and calendar/phase inspections.

The preflight inspection is performed beforeeach flight by the aircrewman to whom the lifepreserver is assigned. A preflight inspection isalso performed by assigned aircrewmen on lifepreservers installed in aircraft.

The special inspection is done on all aircraft-installed life preservers at intervals not to exceed30 days. The inspection is performed at theorganizational level of maintenance by personnelassigned to the aviator’s equipment branch.

When the special inspection is completed andthe life preserver is found satisfactory, theinspection date and inspector’s signature arewritten in the inspection section of the AviationCrew Systems History Card. The 30-day specialinspection may be recorded on a separate historycard f rom the h is tory card recordingcalendar/phase inspections, functional checks,and modifications.

NOTE: The calendar inspection intervalfor LPA type and LPU-21/P seriespreservers assigned to VP squadronselected air reserve aircrewmen has beenextended to 180 days from 90 days,providing the preservers are stowed undercontrolled conditions.

The calendar/phase inspection must beperformed on all life preservers prior to placingthem in service. After that, the inspection cycleis as follows: personal issue life preservers areinspected once every 90 days. Aircraft-installedlife preserver inspection should coincide with theinspection cycle of the aircraft in which installed.In no case should the interval exceed 231 days.Unless operational requirements demandotherwise, the life preserver calendar/phaseinspection is performed by the intermediate levelof maintenance or above. As part of inspectingthe preserver, the functional test is performedprior to placing it in service, every fourthinspection cycle thereafter, and whenever aninflation assembly is replaced. Also, the leakagetest is performed during every inspection cycle.A battery visual inspection for the LPU-23/Pseries and LPU-24/P series will be performedprior to placing life preservers in service, and everyfourth inspection cycle thereafter.

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Figure 6-15.—LPU-3O/P life preserver assembly, parts nomenclature.

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FUNCTIONAL TESTING

Before you attempt to perform a functionaltest, you should ensure that the work areasurrounding the preserver is free of all foreignobjects. This is done to prevent any accidentaldamage to the life preserver. When you performa functional check, you want to ensure that thesystem operates as if the aircrew member wereusing it in an emergency. Therefore, your first stepis to pull the actuation toggle.

The preserver should fully inflate to its designshape without any evidence of restriction in lessthan 30 seconds. If the preserver does not meetthis requirement, you will have to determine thereason and correct it. To do this, first look at yourstem and valve. Sometimes dirt or foreign mattercan cause a slow inflation. If you make anycorrections, the preserver is functionally testedagain.

Deflate the preserver by using a vacuumpump and a 3/8- or 1/2-inch inside diameterrubber hose. Attach one end of the rubber hoseto the vacuum pump, and the other end will goto the oral inflation valve or to the carbondioxide cylinder valve, depending on which typeyou are using. After the preserver has beencompletely deflated, release the oral inflationvalve or put the CO2 cylinder back into the valve.

The functional check is only performed whenthe preserver is placed into service and everyfourth calendar check after that.

LEAKAGE TEST

All life preservers are subjected to a leakagetest each calendar/phase inspection. This test isperformed each time the preserver comes into bechecked, even when a functional test is required.A special test fixture is needed to perform thistest.

Test Fixture

A suggested test fixture, consisting of a three-way valve, pressure gauge, and adapters forcompartments being tested, is shown in figure6-16. The fixture must be fabricated to meet therequirements of the schematic shown in figure6-17.

239.471Figure 6-16.—Leakage test fixture life preserver.

Figure 6-17.—Test rig schematic.

Test Procedure

To test life preservers, proceed as follows:

1. Ensure all carbon dioxide has beenremoved from any preserver that has beenfunctionally tested.

2. To test the LPU-28/P life preserver, inserta 3/4-inch O.D. rubber hose into the oral inflation

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Table 6-7.—Life Preserver Test Pressures

FLOTATION CHAMBER LEAKAGE TEST MINIMUMPRESERVER TYPE TEST SEQUENCE PRESSURE (PSIG) PRESSURE (PSIG)

LPA-2 series Both Chambers Simultaneously 2.0 1.6

LPU-21/P series Both Chambers Simultaneously 2.0 1.6

LPU-23/P series Both Chambers Simultaneously 2.0 1.6

LPU-24/P series Both Chambers Simultaneously 2.0 1.6

LPU-28/P Single Chamber Preserver 2.0 1.6

LPU-30/P Single Chamber Preserver 1.0 0.8

LPP, Pouch Type Single Chamber Preserver 2.0 1.6

hose mouthpiece. Maintain pressure between the

valve on the oral inflation hose and alternately

rubber hose and the oral inflation hosemouthpiece to ensure a good seal. Depress the

position the leakage test fixture valve between themeasuring device, vent, and air supply until theoverpressure relief valve opens (2.5 psig ± .5psig). Rotate the leakage test fixture valve to themeasuring device position to ensure that the lifepreserver is inflated to the proper pressure.Release the valve on the oral inflation hose.Inspect for proper operation of the relief valve.

3. To test all preserver chambers, exceptLPU-28/P, unlock the oral inflation valve andinsert it into the rubber hose. Rotate the valve tothe air supply position and inflate the chamber.Alternately position the valve between themeasuring device, vent, and the air supply untilthe proper pressure is attained.

4. Turn off the air supply, and after aminimum of 15 minutes, readjust the pressure,if necessary, to the original pressure. Refer totable 6-7.

5. Disconnect the air supply and check testfixture for leaks. Ensure all valves are closed.

6. Record temperature and barometricpressure.

7. Four hours after the adjustment period instep 4, record the test pressure.

8. Record temperature and barometricpressure and correct test pressure for any changesin temperature and barometric pressure. Figure6-18 is an example of how you would record thisinformation.

Figure 6-18.—Example for recording readings.

CAUTION

DO NOT SUBMERGE LPU-23/PSERIES AND LPU-24/P SERIES LIFEPRESERVERS IN WATER TO CHECKFOR LEAKS.

After 4 hours, if the pressure of the chamberis below 1.60 psig, inflate to leakage test pressureand coat with a soap solution to locate any leaks.Mark any leak area you find. Rinse the preserverwith fresh water, air dry it, and repair it inaccordance with NAVAIR 13-1-6.1.

If the preserver has held the required pressure,deflate it. Ensure that the inflation valve lever iscocked. Install a carbon dioxide cylinder.

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239.472Figure 6-19.—Checking for silver indicator.

This completes the testing for leaks within theflotation assembly. To complete the calendarinspection, you will have to inspect the remainingcomponents of the life preserver.

VISUAL INSPECTION

The visual inspection is performed along witheach calendar inspection, at which time it isperformed before you perform the leakage test.To perform a visual inspection, inflate thepreserver to 1 psi and look it over real good. Lookfor any fabric cuts, tears, deterioration, orabrasion. Any of these defects can cause leakage.Check the valve stem for security and ensurethat the silver indicator is not visible in the firingcheck port (indicator hole) (LPU-23/P andLPU-24/P). See figure 6-19. If the silver indicatoris visible, the inflator is spent and the automaticfeature of the inflator is negated. A new inflatorshould be installed on the life preserver to replacethe previously spent inflator. Refer to NAVAIR13-1-6.1.

LPU-23/P and LPU-24/P series preserversuse the FLU-8A/P automatic inflator. The servicelife of each FLU-8A/P series automatic inflatoris 66 months from the date of manufacture. Ifservice life expires prior to the next scheduledcalendar inspection, replace the inflator. Referto NAVAIR 11-100-1, Cartridges and CartridgeActuated Devices for Aircraft and AssociatedEquipment. Also refer to NAVAIR 13-1-6.2,section 2-5, Cartridges and Cartridge-ActuatedDevices (General Safety Instructions).

Battery Visual Inspection, LPU-23/P(Series) and LPU-24/P (Series)

To inspect the batteries installed in theFLU-8A/P series inflator, proceed as follows:

WARNING

NO OBJECTS SHOULD BE INSERTEDIN SENSOR PLUG SIDE PORTS FORANY REASON.

With the aid of a standard 17/32-inch socket,remove the sensor plug cap. Remove the batteryand check it for leakage and corrosion. Check thesensor plug cap for cracks. The battery has a two-letter code stamped on it that corresponds withthe month and year of manufacture. The date ofmanufacture for the battery, PN 849AS 160, isdisplayed in the lot number stamped on thebattery case. The battery has a total life of 4 yearsfrom the date of manufacture. Replace anybattery if the total life of the battery expires priorto the next calendar inspection. Check this dateof manufacture on each battery. Also check thedate of installation recorded on the Aviation CrewSystems History Card.

Reinstall or replace battery if needed. Ensurethat the date of installation and date ofmanufacture are recorded on the Aviation CrewSystems History Card. See figure 6-20 for batteryarrangement.

Battery Voltage Testing, LPU-23/P(Series) and LPU-24/P (Series)

Before installing any battery,be sure that it has enough energy

you mustto operate

the FLU-8A/P inflator. A digital readingvoltage multimeter must be used for this test.

239.473Figure 6-20.—Battery arrangement.

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Do not use a needle voltage multimeter. The testleads of the multimeter should be provided witha standard test probe ( + ) and a banana type testplug (–). When using the multimeter, you shouldensure that it is set in the voltage-measuring modeand NOT the resistance-measuring mode. Aresistance measurement will trigger the squib andfire the inflator.

Insert the negative (–) test probe into the endport of the sensor plug. Remove you hand. Faultyreadings can be obtained or the squib may fireif the body becomes an electrical pathway betweenthe sensor pin and any conductive part ofthe inflator assembly. Now, using the pointedpositive (+) probe, touch and maintain contactwith one of the screw heads near the lever end ofthe inflator. Refer to figure 6-21.

Wait 15 seconds for the FLU-8A/P circuit tostabilize after connecting the test leads beforetaking the voltage reading. The voltage readingshould begin at a high value and then graduallyshift downward before final stabilization. If nodownward shift in meter reading occurs, theFLU-8A/P inflator will be rejected.

A reading of +12 volts or more indicates thebattery is at full power and installed correctly. Areading of -12 volts or more indicates the batteryis installed backwards. The battery must be re-versed. A reading of zero volts indicates the bat-tery contact is faulty or the battery is notinstalled properly. Inspect and correct if nec-essary. If a correct battery voltage reading can-not be obtained with a battery of verified fullcharge properly installed, the inflator is defec-tive. Reject and report for an engineering investi-gation according to Volume III, OPNAV 4790.2.

239.474Figure 6-21.—Testing battery.

INFLATION ASSEMBLY INSPECTION

Inspect life preserver inflation assemblies asfollows:

Remove the carbon dioxide cylinder from thevalve assembly.

Examine the inflation device, actuating leverand lanyard, and locking pins for fraying,corrosion, stripped threads, and other damage.

If required, remove any sharp edges from thevalve with a fine, round file.

On LPU-28/P, LPU-30/P, and LPP lifepreservers, operate the toggle three or four times.Ensure that the lever moves freely and the piercingpin moves properly inside valve body.

On life preservers with beaded inflationhandles, operate beaded inflation handle three orfour times. Ensure that the lever moves freely andthe piercing pin moves properly inside valve body.

Ensure that the packaging cord loop is notpinched between the piercing pin and the actuatinglever. If there is free play in the actuating leverwhen it is in its cocked position, the packagingcord loop is pinched. If necessary, reinstall thecord. Refer to NAVAIR 13-1-6.1.

NOTE: Each time the inflation assemblygaskets or the inflation assembly isremoved and replaced for any reason, afunctional test must be conducted. Usenew gaskets when you replace the device.

If any discrepancy is noted in the inflationdevice that is not repairable, remove the assemblyand install a new inflation device.

If carbon dioxide cylinder locking screws areinstalled on LPA type and LPU type lifepreservers, remove them.

Ensure that CO2 cylinder locking screws areinstalled on LPU-30/P life preservers.

Inflation Lanyard Pull Test

Special Equipment Required

Quantity Description Reference Number

1 Pull-Scale, DPP-500 to 50 lb or equivalent

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Figure 6-22.—Inflation lanyard pull test.

To perform the inflation lanyard pull test,proceed as follows:

1. Ensure that the carbon dioxide cylindershave been removed. Actuate the inflation assem-bly. This test is testing the lanyard itself. It isn’tdesigned to test the pull of the inflation assembly.

2. On life preservers with beaded inflationhandles, attach a pull scale to top end (endopposite inflation lanyard) of beaded inflationhandle (fig. 6-22).

3. On LPP and LPA-1/1A life preservers,attach the pull scale to the actuating lanyard atthe binder knot immediately above the knob.

4. Exert a 25-pound straight pull on theinflation lanyard. Remove scale.

5. Examine the inflation lanyard for frays,ruptures, thin spots, split casing, and security ofknots.

6. Replace any unsatisfactory inflation lan-yards.

Installation of Cylinders: LPA-1/1A(Series), LPA-2 (Series), LPU-21/P (Series),LPU-30/P, and LPP-1 (Series)

Prior to installing any CO2 cylinder, it mustbe weighed and the threads cleaned. By using thecylinder thread chaser die, you turn the threadchaser to the full extent of the threads on the CO2

cylinder to cut free any excessive cadmium platingcovering the threads (fig. 6-23).

Weigh the charged cylinder and compare thestamped minimum weight with the scale weight.Discard and replace the cylinder if the scale weightis 2 grams less than stamped minimum weight.Loosen the inflator setscrew if it is installed andensure that the inflator lever is in the cockedposition. To assure a firm cylinder seat, conducta cylinder thread count. The threaded portion ofthe cylinder neck must contain a minimum ofseven full threads to assure a firm cylinder seat

Figure 6-23.—Cleaning threads.

within the valve body. Any cylinder found withless than seven full threads must be discarded.

CAUTION

STEEL THREADS ON CARBON DIOX-IDE CYLINDERS CAN CAUSE DAM-AGE TO ALUMINUM THREADS ONINFLATORS IF THE CYLINDER ISNOT CAREFULLY THREADED. IFBINDING OCCURS DURING THREAD—ING, REPLACE THE CYLINDER.

After performing a functional test, insert anew seat seal gasket from a kit. At intermediateinspection intervals, inspect the condition of thegasket and replace it if necessary. Install the CO2

cylinder into the inflator as far as hand twistingwill permit. Tighten the setscrews, if installed.

NOTE: When you replace the CO2

cylinder to the inflator, ensure that theCO2 cylinder passes through the holdingpatch loop. Do not install the setscrews inLPA-2 and LPU-21/P life preservers. Forall other life preservers, a missing setscrewdoes not warrant removal of the preserverfrom service until a replacement setscrewcan be obtained. Safety-wire the inflatoras required.

Installation of Cylinders, LPU-23/P(Series) and LPU-24/P (Series)

To install cylinders, proceed as follows:

Weigh a charged CO2 cylinder and com-pare the stamped minimum weight with the scale

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WARNING

239.475Figure 6-24.—Inserting new O-ring and CO2 cylinder.

weight. Discard and replace the cylinder if its scaleweight is 2 grams less than its stamped minimumweight.

By using the cylinder thread chaser die, figure6-23, you turn the thread chaser to the full extentof the threads on the CO2 cylinder to cut free anyexcessive cadmium plating covering the threads.

Insert new O-ring and turn the CO2 cylinderinto inflator body as far as hand twistingpermits. See figure 6-24.

Battery Replacement, LPU-23/P(Series) and LPU-24/P (Series)

To replace batteries, proceed as follows:

Remove the sensor plug cap with a standardbox wrench.

BATTERIES MAY EXPLODE IF RE-CHARGED OR IF THEY ARE DIS-POSED OF IN A FIRE.

Remove the old batteries and discard them.

CAUTION

NEVER REPLACE ONE BATTERY;ALWAYS REPLACE THE PAIR.

Remember to record the date of manufactureand the date of installation of new batteries onthe Aviation Crew Systems History Card.

NOTE: Batteries have a total life of 2 yearsfrom the date of manufacture. Do notinstall batteries if their total life expiresprior to the next scheduled calendarinspection.

Install batteries in accordance with figure 6-20.

WARNING

ENSURE THAT THE SENSOR PLUGCAP IS TORQUED TO THE CORRECTVALUE.

On FLU-8A/P only, torque the sensor plugcap to 5 in-lb using 17/32-inch socket and torquewrench.

6-35

CHAPTER 7

SEAT SURVIVAL KIT

Learning Objective: Upon completion of this chapter, you will be able toidentify, inspect, and maintain the RSSK-8 seat survival kit.

The ejection seat survival kit is designed foruse in ejection seat equipped aircraft only.Ejection seat survival kits are designated RigidSeat Survival Kit (RSSKs) -1, -1A, -3, -6B2, -7,-8, and -9; Survival Kit Unit (SKUs) -2A, -3A,and 4A; and Semirigid Restraint and Life SupportAssembly (IULSA) -1. The RSSK-8 is discussedin this chapter.

RSSK-8 SERIES SEAT SURVIVAL KIT

The Rigid Seat Survival Kit-8 Series (RSSK-8series) is designed for use with Douglas

ESCAPAC ejection seats and functions as a seatcushion for the aircrewman as well as a containerfor an emergency oxygen system, life raft and sur-vival equipment (shown in figures 7-1 and 7-2).There are three manufacturers of these kits—Rocket Jet Engineering Corp., Scott AviationCorp., and East-West Industries. The illustrationsin this chapter show the latest configuration ofthe RSSK-8 manufactured by Scott AviationCorporation.

The RSSK-8 has a bonded fiber glass body andan extruded metal lip interconnecting the upperand lower containers. The upper container houses

239.553Figure 7-1.—RSSK-8 closed.

7-1

Figure 7-2.—RSSK-8 open.

the emergency oxygen supply; the lower container,the life raft and survival equipment. The kit isopened by the yellow handle mounted on theforward right side. Two adjustable retainingstraps, permanently mounted on the uppercontainer, provide attachment of the kit to theaircrewman’s torso harness. A flexible oxygen andcommunications hose installed on the aft left sideof the upper container connects the aircrewmanto the aircraft for communications and oxygenfunctions. In the event of a failure of the aircraftoxygen system, emergency oxygen is available bypulling the manual oxygen release on the kit.Oxygen from the kit then flows to the aircrewmanthrough the emergency oxygen system reducer inthe kit. A check valve in the oxygen line preventsemergency oxygen from flowing into the aircraftsystem or overboard from the kit. When theaircrewman ejects, the reducer is automaticallyoperated by a lanyard connected between theactuator and aircraft.

When he sits in the aircraft, the aircrewmanconnectsretainingconnects

the kit quick-release fittings to hisstraps on his torso harness. He alsohis oxygen mask and communication

7-2

239.554

hose to the seat pan quick-disconnect fitting. Thishose can be quickly disconnected by pullingsharply on the hose assembly.

The RSSK-8 is a part of the survival equip-ment used by aircrewman aboard the types ofaircraft listed in table 7-1. As you can see,

Table 7-1.—RSSK-8 Application

Figure 7-3.—Emergency oxygen schematic.

these are high-performance aircraft that canoperate at high altitudes. Therefore, in additionto containing survival gear, the kit also furnishesoxygen to the aviator when he ejects at altitudeswhere there is not enough oxygen to maintainconsciousness.

When the aircrewman ejects from the aircraft,the following events occur:

The automatic actuation lanyard for theemergency oxygen system actuates the reducerassembly at seat ejection. The aircrewman is thensupplied emergency oxygen for descent (fig. 7-3).If automatic actuation of the emergency oxygensystem fails, the emergency oxygen system maybe actuated by the aircrewman by means of themanual oxygen release (green ring). The radiobeacon is automatically actuated by anotheractuation lanyard. The beacon provides a con-tinuous signal during descent.

When a safe altitude is reached, the air-crewman pulls the kit release handle free of thekit. This unlocks the containers and the lower halffalls away but remains attached by the droplineassembly. The life raft, attached to the dropline,is automatically inflated.

239.555

INSPECTIONS

Your concern with this unit is mainly ininspecting it at scheduled intervals or whendamage might be suspected. There are three typesof inspections made at routine intervals: theturnaround/daily/preflight/postflight/transfer,special inspections, and the more detailed ac-ceptance/phased/SDLM inspections. In addi-tion, conditional inspections are unscheduledinspections required as the result of a specificsituation or set of conditions; for example, hard-landing inspections or any inspection directed byhigher authority that is not ordered in a technicaldirective.

The turnaround/daily/preflight/postflight ortransfer inspections consist of a visual-typeinspection performed in conjunction with theaircraft inspection requirements for the aircraftin which the survival kit is installed. Theseinspections are performed by line personnel (planecaptain) or delegated aircrewman who have beeninstructed and found qualified by the aviator’sequipment branch.

The special (7/14 day, etc.) inspections areperformed on inservice survival kits installed in

7-3

aircraft or in ready room issue. These inspectionsare done at the organizational level of mainte-nance by personnel assigned to the aviator’sequipment branch. The date of these inspectionsand inspector’s signature are recorded in theinspection section of the Aviation Crew SystemsHistory Card.

To perform the turnaround/daily/preflight/postflight/transfer or special inspections, visuallyinspect the following:

1. Cushion for secure attachment, rips,tears, and loose or grayed stitching.

2. Release handle for proper seating andcorrosion.

3. Oxygen gauge for FULL indication.4. Emergency oxygen lanyard coupling as-

sembly for spring security.5. Emergency oxygen lanyard for proper in-

stallation and corrosion.6. Manual emergency oxygen release for

condition and security of attachment.7. Container assembly for cracks, breaks,

and other obvious damage.8. Harness assemblies for loose or frayed

webbing, stitching, and cracked or brokenhardware.

9. Lapbelt release assembly for loose ormissing screws and corrosion.

10. Beacon actuator indicator for bent shaft,hairpin cotter for elongation and corrosion.

11. Secure attachment of beacon automaticactuation lanyard (if installed).

12. Seal decal for secure attachment, tears,or rips. If the seal decal is damaged, the RSSKmust be reclosed by IMA.

13. Condition of oxygen hose and secureattachment to kit. If repair procedure has beenperformed on the oxygen hose assembly, checkexternal wiring for secure attachment.

14. For the S-3A aircraft, secure attachmentof externally mounted electrical cable assemblyto oxygen hose assembly.

If any parts must be replaced, note that similarparts from kits made by different manufacturersare not interchangeable. Attempts to substituteone manufacturer’s part for another may causethe kit to malfunction. Make sure the parts andassembly lists are for the proper kit when servicinga kit, or ordering replacement components for it.

If discrepancies are found or suspected, main-tenance control must be notified.

Survival kit assemblies that do not pass in-spection and cannot be repaired in the aircraft

must be removed and replaced by Ready for Issue(RFI) survival kits. Non-RFI survival kits areforwarded to the nearest maintenance activityhaving repair capability.

ACCEPTANCE/PHASED/SDLMINSPECTIONS

The acceptance inspection is performed whenthe survival kit is placed into service. When asurvival kit is an aircraft inventory item, theacceptance inventory inspection and packingserves as the acceptance inspection. In this case,the records concerning the RSSK must beexamined. Phased/SDLM inspection cycle of asurvival kit corresponds to the aircraftphased/SDLM maintenance inspection cycle asscheduled by the Planned Maintenance System.In no case should the phased interval exceed 225days.

Visual Inspection

This inspection will be performed prior to thefunctional check of the kit. Visually check the kitfor the following:

1. The cushion for rips, tears, and generalcondition.

2. The release handle for wear, corrosion, anddamage.

3. The manual emergency oxygen releasehandle (green ring) for damage and security ofattachment.

4. The upper and lower container for cracks,corrosion, and security of hardware.

5. Webbing for loose or frayed stitching andsecurity of attachment.

6. The lapbelt release assembly for loose ormissing screws and corrosion.

7. Swaged balls on cable assemblies forsecurity of attachment. The swaged ball pull testis performed during the acceptance inspectiononly.

Swaged Ball Pull Test

To check the swaged ball attachment to cableassemblies, you will need a nylon cord, Type IIscale (at least 100-pound capacity). Perform thepull test as follows:

1. Remove four screws and cover from as-sembly.

2. Push actuating lever down (fig. 7-4).

7-4

Figure 7-4.—Pushing actuating lever down.

3. Remove spring and two spacer pins. Liftactuating lever assembly with cable inserted inclevis from housing (fig. 7-5).

4. Thread approximately 5 inches of nyloncord, MIL-C-5040, through “LINKS” and tieboth ends together (fig. 7-6).

5. Insert hook of scale into loop of nylon cord(fig. 7-7).

6. Pull the scale towards aft direction of kitand in the normal direction of cable operation.Ensure the adjusting sleeve does not move fromits housing while pull force is exerted. Ensure thatthe links and clevis are not pulled from thehousing more than 1/2 inch. Swaged balls shouldwithstand 100 pounds pull force (fig. 7-8).

Figure 7-5.—Removing spring and spacer pins.

Figure 7-6.—Tying links together.

Figure 7-7.—Attaching scale to nylon loop.

Figure 7-8.—Testing swaged ball.

7-5

Table 7-2.—Troubleshooting

7-6

7. If the assembly fails to meet the specifiedpull force, slide the ball off the cable and swagea new ball in the same direction.

8. Assemble the parts and install the coveron the housing.

Functional Check

This check will be performed at each ac-ceptance/phased/SDLM inspection. It will alsobe performed after any adjustment procedures.Refer to Troubleshooting Chart (table 7-2) priorto making any adjustments.

Materials required to perform the functionalcheck include test stand 59A120 (test stand59A120 is covered in detail in chapter 11 of thismanual), scale (0 to 50 pounds), leak detectioncompound, and a toggle reset tool.

Inspect leak detection compound before usingit. Compound that is not clear and free fromsuspended material or sediment is consideredcontaminated and must be disposed of. Com-pound exhibiting peculiar odors such as acetoneor alcohol is considered contaminated and mustbe disposed of.

Emergency oxygen cylinder pressures used inthis functional test are taken under ideal shopconditions of 70°F or 21°C. Variances in airtemperatures directly affect charging pressures.Refer to table 7-3 for details.

Ensure that the emergency oxygen cylinder isfilled to 1,800 to 2,000 psi corrected pressure.

1. Connect the oxygen outlet hose of the kitto the bell jar coupling C-1 on the test stand, andensure that valve V-2 is open and all other teststand valves are closed.

2. Attach the pull scale to the manualemergency oxygen release handle, and test fordisengagement force. Ensure the manual oxygenrelease is of the separating type before attemptingto disengage it.

3. Measure the force required to disengage themanual oxygen release. This should be 10 to 30pounds, and the emergency oxygen system shouldactuate and indicate 45 to 80 psi on gauge PG-1on the test stand.

4. Reinstall the manual oxygen release (ifseparating type) and reset the reducer.

5. Turn the oxygen supply cylinder to the teststand on.

6. Slowly open valve V-6 on the test stand andadjust the pressure on gauge PG-1 to 90 psi.

Table 7-3.—Amb~nt Air Temperature vs Charging Pressures

Ambient Air ChargingTemperature Pressure

°F °C PSI

0 - 1 8 1550-1750

10 - 1 2 1600-1775

20 - 7 1625-1800

30 - 1 1675-1850

40 5 1700-1875

50 10 1725-1925

60 16 1775-1975

70 21 1800-2000

80 27 1825-2050

90 32 1875-2075

100 38 1900-2125

110 43 1925-2150

120 49 1975-22(X)

130 54 2000-2225

7. Measure the force required to disengagethe manual oxygen release with a scale. This forceshould be 10 to 30 pounds.

8. Using leak test compound, check allpressure lines and fittings on the kit for leakage.No leakage is allowed.

9. Reinstall the manual oxygen release (ifseparating type) and reset the reducer.

10. Using valve V-6, increase pressure untilthe relief valve unseats. However, do not increasethe pressure above 150 psi. Unseating can bedetermined by listening, and by observing gaugePG-1 on test stand.

11. Repeat step 10 several times to establisha correct pressure. Relief valve will unseat at 120to 140 psi when pressure is increased, and resetat 110 psi minimum when pressure is decreased.The pressure is reduced below the openingpressure of the relief valve by closing valve V-6and opening bleed valve V-5. Once reset, the reliefvalve will be leaktight.

12. Check the relief valve with leak testsolution. No leakage is allowed.

13. Close valve V-6 and bleed oxygen pressurefrom the system by opening valve V-5. Allpressure is bled when gauges PG-1 and PG-4indicate zero pressure.

14. Close valve V-5.

7-7

15. Ensure that bleed valve V-2 is opened andall other test stand valves are closed.

16. Measure the force required to disengagethe automatic oxygen release with a scale. Thisforce should be 10 to 30 pounds when it dis-engages; the emergency oxygen system shouldactuate and indicate 45 to 80 psi on gaugePG-1.

17. Reset the reducer.18. Open valve V-5 to bleed pressure.19. When pressure is bled, as indicated by no

indication on gauges PG-1 and PG-4, close valveV-5. Now, observe gauge PG-4 for 2 minutes. Anypressure rise indicates leakage in the valve seat ofthe reducer/manifold.

20. Open valve V-5 and close valve V-2.21. Disconnect the oxygen hose from fitting

C-1.22. Ensure all valves on the test stand are

secured.23. Connect the oxygen outlet hose to fitting

NIP-6. Ensure that valve V-10 is open and allother test stand valves are closed.

24. Connect the test stand hose betweenfitting NIP-5 and fitting NIP-4.

25. Move valve V-1 to the NIP-4 position.26. Ensure that 1,800 to 2,000 psi is in the

oxygen cylinder of the kit.27. Pull the manual oxygen release. Slowly

open valve V-9 to indicate 90 liters per minute ongauge PG-2. Oxygen pressure should be indicatedas 45 to 80 psi on gauge PG-1.

28. Observe emergency oxygen cylinderpressure gauge and allow the system to decreaseto 250 psi while maintaining 90 LPM and 45 to80 psi pressure. When needle of this cylinderpressure gauge is between the E and F of REFILL,pressure is approximately 250 psi.

29. Close valve V-9.30. With zero flow indicated on gauge PG-2,

gauge PG-1 should indicate 45 to 80 psi.31. Reinstall the manual oxygen release (if

separating type) and reset the reducer.32. Bleed the oxygen pressure from the system

by opening valves V-5 and V-2. All pressure is bledwhen gauges PG-1 and PG-4 indicate zeropressure.

33. Disconnect the kit from the test stand.34. Secure the test stand.35. Thoroughly clean all areas wetted with

leak test solution with clean water. Dry them witha lint-free cloth, filtered low-pressure compressedair, or by low-pressure nitrogen.

36. Recharge the emergency oxygen cylinderto 1,800 to 2,000 psi.

37. Perform a release handle pull test on thefully packed kit. (Refer to NAVAIR 13-1-6.3 forinstructions.)

PURGING AND CHARGINGEMERGENCY OXYGEN SYSTEMS

To purge and charge the emergency oxygencylinder, proceed as follows:

Materials Required

Leak detection compound

Oxygen purging electric heater

Nitrogen, type I, class I, grade A

Aviator’s breathing oxygen, type I

Shutoff valve

Pressure regulator

Adapter, filling

1. If the survival kit assembly has not beenremoved from the aircraft, remove the personnelparachute and survival kit in accordance with theapplicable maintenance manual.

2. Remove the oxygen filler valve cap andconnect a filling adapter to the filler valve(fig. 7-9). If the emergency oxygen system is

Figure 7-9.—Filling adapter.

7-8

contaminated or the cylinder has remained emptyfor more than 2 hours, purging is required. If anemergency oxygen cylinder does not warrant thepurging process, proceed to step 10 for thecharging sequence. If it is necessary to releasepressure in the oxygen bot t le be forepurging/filling, pull the emergency oxygenlanyard. This releases the pressure through thepressure reducer. DO NOT release pressurethrough the filler valve or adapter. Releasing high--pressure oxygen through the restriction of thefiller valve causes heat, and a fire or an explosionmay result.

3. Deplete the emergency oxygen cylinder,if necessary.

4. Connect a nitrogen source to the fillingadapter and close the pressure reducer.

5. Slowly pressurize to 100 psi with anitrogen temperature of 110° to 130°C (230° to266°F) using an electric heater.

6. Turn off the nitrogen source and depletethe oxygen cylinder.

7. Repeat steps 5 and 6, twice.8. With the pressure reducer open, turn on

the nitrogen source and purge for 10 minutes ata temperature of 110° to 130°C (230° to 266°F).

9. Turn off the nitrogen source anddisconnect it.

10. Connect the oxygen source to the fillingadapter with a suitable pressure regulator andshutoff valve. Reset the pressure reducer.

11. Slowly pressurize to 100 psi.12. Deplete the cylinder to 50 psi.13. Ensure that minimum slack exists in the

actuating cables of the reducer/manifold, and thatthey are tight enough to ensure full engagementof the toggle arm.

14. Charge the emergency oxygen system instages in accordance with table 7-4 until thepressure gauge indicates correct pressure forexisting ambient temperature, as indicated in table7-3. Carefully observe the scheduled filling stages,since rapid application of oxygen pressure creates

Table 7-4.—Charging Stages

heat, which may result in fire or explosion. Allowno less than 3 minutes for each filling stage and2-minute intervals for cooling between stages. Ifthe kit is to be stored or shipped, fill it to 200 psi(when needle on gauge bisects E of REFILL).

15. Loosen the filling adapter until allpressure is bled from the high-pressure line.Remove filling adapter. Visually ensure that thefiller valve does not turn as the filling adapter isremoved. Serious injury could result.

16. Apply leak test compound around thefiller valve, gauge, and reducer. Check for leaks;then wipe connections clean, using a lint-freecloth.

17. Replace the oxygen filler valve cap on thefiller valve.

18. If the personnel parachute and survivalkit assembly were removed from the aircraft instep 1, reinstall them at this time.

As you know, there are a variety of seat kitsavailable. Although the basic principles ofoperation are similar, they differ in accordancewith the aircraft in which they are issued, theircontents, and the type of ejection seat in theaircraft. Additional information concerningupdating, modification, inspection, maintenance,etc., of seat survival kits can be obtained fromNAVAIR 13-1-6.3. Aviation Crew Systems SeatSurvival Kits.

7-9

CHAPTER 8

CARBON DIOXIDE

Learning Objective: Upon completion of this chapter, you will be able todescribe, inspect, recharge, and perform maintenance on carbon dioxidecylinders and transfer units.

Carbon dioxide is a heavy, colorlessgas. The chemical symbol for carbon dioxideis CO2. You will f ind that most peopleuse this symbol when referring to carbondioxide.

C O2 doesn’t burn and does not sup-port combustion; therefore, it makes a finefire-fighting agent. It is strongly recommendedfor use on electrical fires. The servicingof fire-fighting equipment is not part of thePR rate, and so this text does not coverfire extinguishers.

As a PR you deal with life raft and lifepreserver CO 2 cylinders, which you weigh,recharge, and repair.

Carbon dioxide is ordinarily procured fromlocal commercial sources. It is stored in standardsupply cylinders that contain 50 pounds of carbondioxide when full.

Before learning how to recharge CO 2

cylinders, you should be familiar with thefollowing information:

In its gas form, carbon dioxide is 1.53times heavier than air. C O2 g a s c a n b econverted into a liquid by applying pressureto the gas. With as little as 600 psi ata temperature below 88°F, the CO2 g a scan be converted into a liquid and storedin that state until it is subjected to theoutside atmosphere. By opening the cylindervalve and letting the carbon dioxide escapeinto the atmosphere, you cause a rapid drop

in pressure. As the CO2 escapes throughthe small opening, it forms carbon diox-ide snow. This snow, when compressed intoblocks or cubes, is known as dry ice.At atmospheric pressure, dry ice will re-main at – 110°F, directly evaporating into CO2

gas. CO2 exists as a liquid only when underpressure.

Whenever you are working with CO 2

in any of its three stages—gas, liquid, or dryice, you should be aware that small percent-ages of CO2 in the air causes tirednessand perhaps headaches. Experiments haveshown that a 3-percent concentration in theair doubles your breathing effort, 5 percentcauses panting, 8 percent causes marked dis-tress, and 10 percent causes unconsciousnessvery quickly.

Treatment of exposed personnel includesremoving them from the CO2-laden atmos-phere, artificial resuscitation, administeringoxygen, and keeping the patient warm.

CO2 RECHARGE EQUIPMENT

Carbon dioxide recharge equipment ismanufactured for the Navy by several dif-ferent companies. The two most widely usedunits are those manufactured by the C-O-TWO Company of Newark, New Jersey (donot confuse this company with the chemicalsymbol CO2) and the Walter Kidde Companyof Belleville, New Jersey.

8-1

239.39Figure 8-1.—C-O-TWO recharge or transfer unit (supply

cylinder without a syphon tube).

A typical C-O-TWO recharge unit is shownin figure 8-1 and consists of a supply cylindercontaining 50 pounds of CO2, a tilting rack forinverting the supply cylinder, a motor-drivenpump, a rack for inverting the cylinder beingrecharged, a scale for determining the weight ofthe cylinder being recharged, and the necessaryhigh-pressure hoses, control valves, adapters, etc.,to properly hookup the equipment. The two unitsare covered in detail in the PR 1 & C.

Before learning the operation of any specifictype of recharge equipment, you should befamiliar with the following general information,which applies to all units.

Carbon dioxide recharge equipment pumpsCO 2 in its liquid state only, and the amount ofliquid CO2 a cylinder contains varies with thetemperature and pressure. For example, astandard 50-pound supply cylinder containsapproximately 38 pounds of liquid CO2 and 12pounds of gaseous CO2 at a temperature of 70°F.It follows, then, that the cooler the supply cylinderand cylinder being recharged, the more efficientthe operation of the transfer equipment. For thissame reason, the time required to recharge anempty cylinder increases with the temperature ofthe cylinders.

239.144Figure 8-2.—CO2 supply cylinder.

When recharging a cylinder, it remains coolerand may be filled faster if inverted, rather thanleft in an upright position. Large cylinders, whichare impractical to invert, may be placed in ahorizontal position for charging.

Standard commercial supply cylinders in50-pound sizes are obtained with or without asyphon tube. When transferring from a cylinderwithout a syphon tube, the cylinder must beinverted. Supply cylinders with syphon tubesshould be maintained in an upright position, notmore than 60 degrees from vertical.

CO2 SUPPLY CYLINDERS

Figure 8-2 illustrates the standard supply cylin-der used universally in recharging various types ofCO 2 cylinders. A cutaway view of the cylindervalve is also shown. Table 8-1 lists some of themost pertinent data concerning supply cylinders.

INSPECTING CO2 CYLINDERSAND RECHARGING

Cylinders, including some of those of newmanufacture, continue to bear ICC markings and,

8 - 2

Table 8-1.—Specifications On Supply Cylinders

Capacity at normal pressureand temperature* . . . . . . . . . . . . . . . . 50 pounds

Working pressure . . . . . . . . . . . . . . . . . 1,800 to 2,015

psiICC specification . . . . . . . . . . . . . . . . . ICC3ADimensions (approx.). . . . . . . . . . . . . Diameter, 8 1/2

inches; length,51 inches

Weight, empty . . . . . . . . . . . . . . . . . . . 110-115 pounds

Outlet connection . . . . . . . . . . . . . . . . 3/4 inch

* Temperature of 68° - 70°F and atmospheric pressure.

until amendment to Department of Transporta-tion (DoT) regulations, such markings will remainin use.

Compressed gas cylinders, including CO2

cylinders must not be refilled if the hydrostatictest date has expired. This date, expressed bymonth-year, e.g., 8-70, is stamped on the shoulderof the cylinder each time the cylinder is retested.The hydrostatic test date is considered as havingexpired if the latest date stamped on the cylinderprecedes the current date by more than 5 years.

Cylinders that do not exceed 2 inches in out-side diameter and that are less than 2 feet longare exempt from the hydrostatic retest.

The hydrostatic retest date applies to multi-place life raft cylinders; if the cylinder is due fora test, discharge and disconnect the cylinder.Obtain a new cylinder from supply as a re-placement, and forward the old cylinder to anactivity capable of conducting a hydrostatic test.

Many nonshatterable cylinders are identifiedby the words NONSHATTERABLE, NON-SHAT, or SHATTERPROOF stamped (notstenciled) on the shoulder or side of the cylinder.Substitution of a “shatterable” for a “non-scatterable” cylinder is not authorized.

Personnel who handle compressed gas cyl-inders must be familiar with the color coding ofcylinders. Color coding is provided as a hazardwarning, and should not be used by itself toidentify the contents of a cylinder. In the event of

conflict with other markings, or doubt as to thecontents, the cylinder should be returned to thelocal supply activity, (non-RFI).

All carbon dioxide inflation cylinders mustbe painted gray, and markings must be inblack letters 1/4-inch high. The informationmust include gross weight, tare weight, weightof carbon dioxide, and date of latest recharge.Paint and stencil the cylinder as required,and ensure that all markings are included asnecessary.

Ensure that all carbon dioxide cylinders usedfor life raft inflation assemblies received fromsupply, except those used on the one-man rafts,have syphon tubes installed.

Gently tap the inverted cylinder with asmall piece of wood. If any rust or othercontamination falls from the cylinder, re-ject that cylinder, and draw another cylinderfrom supply; repeat the contamination check.Replace the stem in the inflation assemblyvalve, install a new sealing washer, and threadthe inflation assembly valve onto the cylinder andtighten.

Inspection for deterioration of the cylinder willconsist of a visual examination for the defectslisted below.

Cylinders with defects that approximate thephysical dimensions indicated in the following listwill be condemned and returned to supply.

1. Corrosion pits in a general corrosion areathat exceed a depth of 1/32-inch, or isolated pitsnot in a general corrosion area that exceed a depthof 5/64-inch.

2. Dents that exceed a depth of 1/16-inch, orwhose major diameter is more than 32 times thedepth.

3. Cuts or gouges more than 1/16-inch, orwhose major diameter is more than 32 times thedepth.

4. Visible arc or torch burns.

5. Evidence that the cylinder has been in afire.

6. Discernible bulges.

8-3

Figure 8-3.—CO2 recharging schematic.

Now that you have inspected the CO2 cylinder,you are ready to recharge the bottle. Figure 8-3shows a recharging setup. Notice in the figure thatyou need scales, a recharge pump, a supplycylinder, and the necessary lines and valves.Proceed as follows:

1. Place the CO2 cylinder on the scales.

NOTE: An accurate scale with a capacityof 100 pounds is necessary. The scaleshould have 1/100 pound graduations.

2. Weigh and record tare weight (emptyweight of cylinder, valve and cable assembly) ofthe inflation assembly.

3. Install proper charging adapter on theinflation assembly.

4. Secure the inflation assembly to theweighing pan located on the scales before applyingany pressure to the cylinder being recharged.

5. Open the supply cylinder valve, fill linevalve, and relief valve. This is done to purge (getthe air out of) the complete line. Once the lineis purged, close the fill line valve and the reliefvalve. You must be careful when purging the line;you are dealing with a high pressure. If you donot secure the fill line before you apply pressure,the line may start a whipping action and damageanything or anyone that it hits.

6. After purging the line, connect the fill lineto the inflation assembly. Ensure that the line isfree from contact with any objects along the entiredistance from the compressor to the charging

Table 8-2.—Carbon Dioxide Charge

239.359

adapter. If the line does not hang free, accurateweight reading cannot be obtained. At this time,you must zero your scales. By zeroing the scales,you will be able to recharge the exact amount ofCO2 into the inflation assembly. See table 8-2 forcarbon dioxide charges.

7. Ensure that the inflation assembly valve isopen. If it is closed, you cannot recharge theassembly.

8. Open the fill line valve slowly until you hearC O2 flowing through the line and into theinflation assembly, and the scale’s indicator showsthe recharging cylinder is gaining weight.

9. Allow carbon dioxide to cascade (flowfreely) from the supply cylinder until the scales

8-4

indicate that the cylinder being recharged isn’treceiving anymore CO2. If you haven’t reachedthe gross weight required (tare weight plus weightof charge) start the compressor and completecharging. Stop the compressor upon reaching theproper gross weight. At this time, you havecompleted the recharging process, and you mustsecure the equipment.

10. To shut the equipment down, start bysecuring the inflation assembly valve, and shut offthe compressor. Then secure the fill line valve.Open the relief valve; this will relieve any pressureyou may have in the line between the fill line valveand the inflation assembly. Disconnect the fill linefrom the inflation assembly and remove thecharging adapter. To secure the rest of the system,all you have to do is close the supply cylinder valveand bleed the system by opening the fill line valve.

If, during the recharging process, the cylinderbeing charged ceases to gain in weight, there maybe one of two things wrong:

1. The supply cylinder may contain less than10 pounds of carbon dioxide. In this case, a fullycharged supply cylinder should be used and thepartially charged cylinder reserved to start therecharging of an empty cylinder.

2. The connecting lines may have becomestopped up with carbon dioxide snow. This maybe caused by water in the supply cylinder or toosmall a valve passage (less than 1/8 in) in thesupply cylinders. In this case, the disc assembly(disc-type valve) or the cylinder valve (seat-typevalve) should be securely seated and the pumpshut off. The connections should be broken andcleared of the carbon dioxide snow. The line willactually clear itself if allowed to stand for somelength of time, but this can be hastened byapplying a flame or torch to the tubing. The lineshould then be blown out with air to clear it ofwater or foreign matter.

MAINTENANCE FOR THE C-O-TWOTRANSFER UNIT

Once every month, inspect the level of the oilin the crankcase and see that it is within the limitsspecified.

Once every 6 months, lubricate the idler shaftwith two or three applications of light cup grease;also, lubricate the gear teeth with a thin coatingof the same grease. With a small brush, apply a

light coating of Vaseline to the piston rod. Todo this, dip the brush in Vaseline and hold thebrush against the piston rod while rotating thegears manually until the piston rod has beencoated completely. If necessary, tighten thepacking at the piston stem. A special wrench isneeded for this operation. Do not tightenexcessively. Because of the design of the packing,it is necessary to make only a snug adjustmentto have it hold tightly.

Keep the commutator or the motor clean.Under normal operating conditions, thecommutator will require only occasional cleaningwith a dry piece of nonlinting cloth. Neverlubricate the commutator.

Drain and refill the crankcase at least once ayear. The bearing housings of the motor, whichalso need attention at this time, should be cleanedand regressed by a qualified electrician. Use table8-3 for servicing intervals.

MAINTENANCE OF THE WALTERKIDDE TRANSFER UNIT

The instruction book on lubrication for theWalter Kidde transfer unit recommends inspectingthe oil level in the crankcase periodically andchanging it as necessary. Here, experience withpumps dictates the time of action. One canestablish and maintain a schedule compatible withthe experience gained through operating theequipment. The plunger packing needs no oil.

Table 8-3.—C-O-TWO Unit Servicing Intervals

8-5

CHAPTER 9

SEWING MACHINES

Learning Objective: Upon completion of this chapter, you will be able toidentify and maintain the different types of sewing machines used in the process

of repairing or fabricating survival equipment.

Sewing machines are like any other tool youuse. If you don’t have the correct one, the taskis harder or impossible to complete. The sameapplies to sewing machines. You need the rightmachine for the job; whether it be lightweight,medium weight, or heavyweight, there is amachine designed to perform each task. You workwith various types of sewing machines in theprocess of repairing or fabricating items in theshop. You need to have all the knowledge and skillYOU can possibly acquire about these machines tofulfill your duty as a PR. If you don’t know howto operate and maintain the sewing machines, theywill stand idle, not operate properly, or not workat all. When you have a job to do, you needequipment that is operational. Without the properknowledge of sewing machines, you will not havethe confidence to perform necessary sewingmachine repairs.

Before you can learn to operate and maintaina sewing machine, you must learn the languageof the sewing trade. Through your supervisor andthis text, you should become familiar with thislanguage. It is very important that you form ahabit of referring to the parts of a sewing machineby their proper names. It would be difficult tocommunicate with other PRs and impossible topass a rating exam if you do not know the propernames of the different parts of a sewing machine.Take time to study the illustrations in this chapterthat show the important sewing machine parts andtheir names.

Sewing machines are classified as two types—OSCILLATING and ROTARY. Both types areoperated by electric motors and are fitted withrheostats and special clutch arrangements thatenable the operator to control the speed.

When it comes to classifying sewing machinesinto oscillating and rotary, the important part is

the rotary hook and oscillating shuttle. This is thedevice that is out of sight in the base of themachine, but does the very important job offorming each stitch after the needle has passedthread through the fabric.

Oscillating sewing machines have a sewinghook that rocks back and forth through half ofone revolution to complete one stitch.

Rotary sewing machines have a hook thatmakes two complete revolutions to complete onestitch.

The type of stitch commonly used and madeby sewing machines in repair work is thelockstitch. The lockstitch makes use of twoseparate threads. One comes from the spool downthrough the eye of the needle, the other from thebobbin. In making the lockstitch, these twothreads must become interlocked, as shown infigure 9-1.

The thread passing through the eye of theneedle is pushed down through the material beingsewn. As the needle travels downward to thematerial, a spring pulls tension on the needlethread to keep it taut to prevent any slack thatmight tangle the thread around the needle.

After the needle reaches its lowest position andstarts its upward movement, the process shownin figure 9-1 begins. A small loop of thread formsalongside the needle beneath the throat plate. Thesewing hook catches this loop and carries itaround the bobbin, which floats in its track in thebobbin case (view B of figure 9-1). By locking theloop of needle thread around the bobbin thread,the sewing hook forms the stitch.

As the needle completes its upward movement,the thread tension disks hold the needle threadfirmly. The thread take-up lever, rising quickly,pulls on the loop that has been formed, and thustightens the stitch. When the thread take-up lever

9-1

239.261Figure 9-1.—The lockstitch.

reaches its highest position, the stitch is com- assembly; the UPRISE (14) houses the armpleted. (See views C and D of figure 9-1.) shaft connection belt; the BALANCE WHEEL

Now look at figure 9-2. The standard sewing (12) is connected to the arm shaft in themachine has four basic parts: bed, uprise, arm, ARM (11), which operates the needle barand face. The BED (1) houses the linkage from mechanism in the FACE (6) of the ma-the safety clutch pulley to the sewing hook chine.

9-2

239.262Figure 9-2.—Sewing machine 31-15.

The machine is powered by an electric motor,which is connected to the motor driving pulley bya clutch. You connect the motor to the clutch bypressing the forward part of the foot treadle. Theaft part of the treadle is the brake, which actsupon the clutch.

The material to be sewn is held in position onthe feed dog by the presser foot. The pressure ofthe presser foot upon the material enables the feeddog to push the material forward each time theneedle goes up. The pressure of the presser footon the material is released either by a knee lifteror a hand lifter. The presser foot can be raisedby pushing the knee lifter to the right. The handlifter is located behind the face of the machine.The presser foot may be lifted and locked intoposition by raising the hand lifter to its highestposition.

OSCILLATING TYPE SEWINGMACHINES

Two of the most commonly used oscillatingsewing machines are the 31-15 and 7-33, both ofwhich are discussed in this chapter.

SINGER SEWING MACHINE 31-15

When starting out as a PR, the 31-15 sewingmachine will probably be the one you’ll like touse. This machine is smaller and lighter than mostof the other machines used in the parachute loft.The manufacturer calls the 31-15 a tailoringmachine. It is used to sew and repair clothing,uniforms, shirts, flying clothing, jackets, andlightweight protective covers.

The 31-15 is an oscillating sewing machine thathas a recommended speed of 2,200 stitches perminute and makes a lockstitch. It is very good forsewing nylon cloth, and can be used for sewinglightweight canvas up to 8 ounces. The numberof stitches can be regulated from 7 to 32 stitchesper inch.

When the 31-15 machine is in operation, thebalance wheel turns over toward the operator.When hand-turning the balance wheel, alwaysrotate it in this direction. The components of theSinger Sewing Machine 31-15 are shown in figure9-2.

9-3

The following practices and procedures helpto ensure safe and smooth operation of the sewingmachine:

1. The balance wheel must always turn towardthe operator.

2. Do not run the machine with the presserfoot resting on the feed dog without materialbeing under the presser foot.

3. Do not run the machine when both bobbincase and needle are threaded unless there ismaterial under the presser foot.

4. Do not try to help the machine by pullingthe material. You may bend or break the needle.If properly adjusted, the machine feeds the workwithout assistance.

5. The slide over the bobbin case shouldbe kept closed when the machine is in op-eration.

6. Keep your head away from the thread take-up lever and needle bar at the top of the sewingmachine face.

7. When running the machine, do not takeyour eyes away from the needle and presser foot.

8. Keep your fingers from under the needle.9. When running the machine, keep your

fingers away from the belt and pulley areas.

10. Never attempt threading the needle whenthe machine is turned on.

Lubrication

To ensure easy operation and to preventunnecessary wear of the moving parts, all sewingmachines need oiling. When a machine is inconstant use, it should be oiled twice a day. Anewmachine should be oiled more frequently whenin constant use. Use only one drop of oil at eachoiling point. A 10W mineral oil is recommended.

Oiling points for the 31-15 machine are shownin figures 9-3, 9-4, and 9-5. Oil should be appliedregularly to the shuttle bearing in the shuttle race.Occasionally, remove the faceplate and apply oilto the bearings and points that are uncovered.

Timing the 31-15

There are two distinct timing operations forthe 31-15 machine. One operation times the needlewith the shuttle; the other timing operation timesthe feed dog with the needle. Both the needle withthe shuttle and the feed dog with the needle must

239.263Figure 9-3.—Oiling points at the front of the machine.

9-4

239.264Figure 9-4.—Oiling points at the back of the machine.

239.265Figure 9-5.—0iling points at the base of the machine.

9-5

2. Move the needle bar up or down asrequired; and then tighten the screw.

239.443Figure 9-6.—Timing needle with shuttle.

be in proper time for the machine to functionproperly. See figure 9-6.

Timing the Needle with the Shuttle

If a class 31 sewing machine does not formthe lockstitch, if it skips stitches, or if it frays orbreaks thread, the needle is not moving in theproper relationship with the shuttles motion. Firstmake sure you have the right needle. Check theneedle for the correct class, variety 16 x 87, andsize. Insert the needle in the needle bar (longgroove to the left) as far as it will go (fig. 9-6).Next compare the needle stroke to the shuttlestroke. To do this, remove the throat plate. Turnthe balance wheel toward you until the point ofthe shuttle on its forward stroke reaches the centerof the needle while the needle is on the upstroke.At this time, the needle bar should have risen 1/10inch and the point of the shuttle should be 1/16inch above the eye of the needle, as shown in Ao f figure 9-6.

NOTE: Prior to making adjustments to thesewing machine, always follow thetroubleshooting chart in Table 9-1.

If the needle eye is not in this position, thefollowing steps should be taken:

1. Loosen the needle bar connecting studscrew, as shown in B of figure 9-6.

3. Rotate the balance wheel through the fullcycle to check the timing.

4. Replace the throat plate.

Timing the Feed Dog with the Needle

The feed driving eccentric is an adjustableconnection between the arm shaft (the shaft in thehead) and the feed rock shaft (first shaft beneaththe bed of the machine). If the feed mechanismis properly timed, the feed dog should be on itsdownstroke and level with the throat plate whenthe point of the needle reaches the material. Ifthere is a twisted knot every 1 to 2 inches on thebottom of your material, check the timing of theneedle before adjusting the feed mechanism.

To adjust the feed eccentric, first lower thestitch regulator to the lowest position so themachine forms its longest stitch. Turn the balancewheel until the feed dog is on its downstroke andis flush with the throat plate. Move to the rearof the machine and take off the arm side cover.Turn the balance wheel away from you until thefeed eccentric collar setscrew is visible (fig. 9-7).Hold the collar with your left thumb. Loosen thescrew and rotate the balance wheel away from youuntil the needle, on its downstroke, reaches thematerial. Tighten the setscrew. Rotate the balancewheel to check the timing. Recheck the timing ofthe shuttle point with the needle. When you timethe feeding mechanism, you may throw the needleout of time with the shuttle.

239.444Figure 9-7.—Feed eccentric.

9-6

Table 9-1.—Troubleshooting Chart

TROUBLE PROBABLE CAUSE REMEDY

Needle breakage. Incorrect class and variety needle being Use correct class and varietyused. needle.

Needle loose in clamp. Tighten needle clamp screw.

Needle too small for fabric. Use larger needle.

operator pulling on the material. Allow machine to feed material.

Needle thread breakage. Thread too heavy for needle. Use larger needle or smallerthread.

Right twist thread being used. Use left twist thread.

Damp or defective thread being used. Use only dry smooth thread.

Machine incorrectly threaded. Check machine for properthreading.

Needle incorrectly set. Set needle with long groove tothe left.

Needle thread tension too tight. Loosen needle thread tension.

Thread take-up spring out of adjustment. Adjust thread take-up spring.

Burr on bobbin case, Shuttle point or Smooth with emery cloth.tension disks.

Thread rubbing against presser foot. Adjust presser foot.

Needle has burr on eye or point, blunted Replace needle.or bent.

Bobbin thread breakage. Bobbin tension too tight. Adjust bobbin tension.

Bobbin incorrectly threaded. Thread bobbin to revolve clock-wise.

Bobbin wound too full to revolve freely. Remove some of the bobbinthread.

Rounds of bobbin thread lapped over one Insure bobbin thread is straightanother. when winding bobbin.

Bobbin case is dirty. Clean and lubricate bobbin case.

Skipped stitches. Machine out of time. Time needle to shuttle.

Thread controller spring out of Adjust thread controller spring.adjustment.

Drawing of seam. Needle and bobbin tension too tight. Loosen needle and bobbin ten-sion.

stitches piled up. Stitch regulator out of adjustment. Adjust stitch regulator.

Pressure on presser foot too tight. Loosen presser foot adjustmentscrew.

Feed dog striking throat plate. Feed dog set too high. Lower feed dog to correctheight.

9-7

Adjusting the Feed Dog

The height at which the feed dog should beset depends on the weight and number of pliesof the material being sewn. If the feed dog is settoo low, the material does not feed through themachine; if it is set too high, it may cut or fraythe material. The recommended height of the feeddog for sewing lightweight canopy material isslightly less than one tooth above the throat plate.If you are sewing heavier material, raise the feeddog to a height that ensures positive feeding ofthe material. After you have decided on thecorrect height for the project you are working on,adjust the feed dog accordingly, by loosening andthen tightening the screw, as shown in figure 9-7.You must remember that each time the height ofthe feed dog is changed, the feeding mechanismmay be out of time. For this reason, set the feeddog first, and then make the necessary adjustmenton the feeding mechanism. Since most of yourcanopy repairs involve material of approximatelythe same weight, one-time adjustment of the feeddog is usually sufficient. Repeated changing ofits height is not necessary.

Adjusting the Thread Take-up Spring

To adjust correctly the take-up spring in thetension assembly (fig. 9-8), you should firstunderstand its normal operation. The thread take-up lever pulls the thread take-up spring downabout even with the slack thread regulator whilethe needle is going up. While the take-up leveris coming down with the needle, the thread take-up spring pulls the slack out of the thread andkeeps it from getting under the needle. If you donot have this adjusted properly, a loop can form

239.445Figure 9-8.—Tension assembly.

over the needle hole in the throat plate, and theneedle can split the thread as it enters the needlehole. You should set the spring about 1/4 inchabove the slack thread regulator. The thread take-up spring should be set so that the spring will havecompleted its downward motion and be restingon the stop when the needle, on its downstroke,reaches the fabric.

To adjust the spring, loosen the setscrew, asshown in figure 9-8. To put more tension on thespring, you turn the assembly clockwise; to putless tension on the spring, you turn the assemblycounterclockwise.

It may be necessary for you to replace thethread take-up spring because it can bend andbecome weak. Loosen the setscrew and insert ascrewdriver into the slot of the tension screw stud(fig. 9-8). Turn the stud to the left until it isscrewed out of the thread take-up springregulator.

Remove thumb nut (fig. 9-8), the tensionspring, and tension discs. The take-up spring isnow free for removal. After replacing the oldspring with a new one, assemble the parts inreverse procedure.

Replacing the Needle

While replacing a needle is a relatively simplejob, you must know a few things about needlesin order to decide which needle is required whena needle must be replaced. It is very importantthat the proper needle be used to ensure goodmachine operation. The selection of needles byclass, variety, and size for different machines andmaterials is necessary to eliminate threadbreakage, needle breakage, skipped stitches, andfraying of the thread.

Needles for the various machine classes areselected and ordered by needle number and size.The needle numbers consist of a class number andvariety number separated by a‘‘x”; for-example,the class and variety needle 16 x 87 is used in the31-15 sewing machine. Cloth point needles areround, sharp-pointed needles used for sewingcloth, since they do not cut the strands as theyare forced between the woven threads of thefabric. Many different varieties of cutting pointneedles are available, but they are used only forsewing heavy leather. Figure 9-9 shows the shapeof the openings made in material by the clothpoint (view A), twist point (view B), and thediamond point (view C). Figure 9-9 illustrates whyit is important that a round-pointed needle be usedin cloth; views B and C show how cutting pointneedles can cut the warp and filler threads.

9-8

239.446Figure 9-9.—Shapes of needle points.

239.447Figure 9-10.—Sewing machine needle.

Machine needles have along groove on oneside, and either a short groove or a scarf on theopposite side, as shown in figure 9-10. Thepurpose of the grooves is to allow the thread tofall back into the needle when it enters the materialto prevent the thread from breaking or fraying;therefore, it is important that the long groove beplaced in the machine properly. On different classmachines, the direction varies with the positionof the bobbin assemblies. 0n class 31 machines,the long groove is placed to the left. The scarf isto prevent the oscillating shuttle from striking theneedle as it passes close to the needle to pick upthe thread loop to form the lockstitch.

Needles are sized by the diameter or gauge ofthe needle and the needle eye. The selection ofthe correct size needle is determined by the sizeand type of thread and material used. The threadmust pass freely through the eye of the needle toprevent thread fraying or breaking. The sizes ofthe class 16 x 87 needles used for most sewing willrange from size 18 through size 22. The needlesize number increases with the diameter of theneedle; therefore size 18 needles are used forlighter weight materials than size 22. Listed beloware some of the needle sizes you will be workingwith and their uses:

1.

2.

3.

4.

5.

Size 18. For sewing two to four plies of thinmaterial, such as silk, nylon, or rayon, withsize E thread.

Size 20. For sewing five or more plies.

Size 21. For sewing two to four plies ofmedium weight materials, such as aircraftcloth, 12-ounce duck, light leather, andartificial leather.

Size 22. For sewing two to four plies ofmedium weight material, such as heavyduck, lightweight and medium weight web-bings, and russet leather.

Size 24. For sewing elastic or rubberized—materials.

You should check the condition of the needle’spoint before you start to sew. A dull or roughround needle acts the same as a cutting needle.It cuts or pulls threads and may weaken the seam.The condition of a needle may be checked bysliding the fingernail over the point. If it scratchesor catches the nail, the needle should be replacedwith a new one. A dull needle may be sharpenedby placing it in the chuck of a drill press, and thedrill operated at high speed while holding a finegrain sharpening stone lightly against the side ofthe needle at the proper angle. The point is thenpolished with a piece of russet leather.

Having selected the proper needle, turn thebalance wheel toward you until the needle barmoves to its highest point. Loosen the needleclamp screw and put the shank of the needle upinto the groove as far as it will go. Turn the longgroove so that it faces to the left and is directlyin line with the arm of the machine. Then tightenthe clamp screw, and check to see that the needledoes not turn or slip. For troubleshooting, referto table 9-1.

9-9

Threading the Machine

Threading a machine is a very simple job. Theprocedure may vary slightly with different models;but after working with the various machines inthe loft, the task becomes automatic.

The component parts used in threading the31-15 sewing machine are shown in figure 9-11.Use this figure in studying the procedures thatfollow. Pass the thread from the thread stand tothe thread post on top of the machine, right to leftthrought the bottom hole, and then right to left

239.268Figure 9-11.—Threading the 31-15 sewing machine.

through the top hole. Pass the thread from right toleft through the top hole in the thread retainer(1). Pass the thread from left to right through themiddle hole in the thread retainer (2). Pass thethread from right to left through the bottom holein the thread retainer (3). The thread is then passeddown and under from right to left between thetension disks (4). Draw the thread up into thethread take-up spring (5), drawing the thread upand beyond the spring end so that it comes out inthe center of the spring. The thread is then placedunder the tension thread guard (6). Pass the threadup and from right to left through the hole in thethread take-up lever (7). The thread is now drawndown through three thread guides (8), (9), and(10). Pass the thread from left to right through theeye of the needle (1 1). Draw about 2 inches ofthread through the eye of the needle to beginsewing.

Removing the Bobbin Case

Before attempting to remove the bobbin case,turn the balance wheel toward you until the needlemoves upward to its highest position.

Remove the slide in the bed of the machineso you can see what you are doing. Reach underthe table with your left hand, and, using yourthumb and forefinger, open the bobbin case latch(fig. 9-12) and lift out the bobbin case.

While the latch is held open, the bobbin isretained in the bobbin case. Release the latch, turnthe open end of the bobbin case down, and thebobbin will drop out.

Winding the Bobbin

The bobbin winder is fastened to the table withits driving pulley in front of the sewing machine

239.269Figure 9-12.—Removing bobbin case.

9-10

Figure 9-13.—Winding the bobbin.

belt. The bobbin winder is so positioned to allowthe pulley to drop away from the belt whensufficient thread has been wound on the bobbin.

Figure 9-13 illustrates the bobbin-windingoperation. The procedure is as follows: Place thebobbin on the bobbin winder and push it on theshaft as far as it will go. Pass the thread from thespool down through the thread guide. Loop thethread around back and through the tension disks.

The thread is then wound around the bobbina few times and the pulley pushed up against themachine belt. The bobbin can be wound while themachine is being used for sewing. If there is nomaterial under the presser foot, make certain thatthe presser foot is raised and not riding on thefeed dog while winding the bobbin.

When sufficient thread has been wound on thebobbin, the pulley on the bobbin winder dropsback from the machine belt automatically. If thethread does not wind evenly on the bobbin, loosenthe setscrew in the tension bracket and move thebracket to the right or left as required; then tightenthe bobbin winder stop latch screw. The amountof thread wound on the bobbin is regulated bythe bobbin winder stop latch. To wind morethread on the bobbin, turn the screw to the right;to wind less thread on the bobbin, turn this screwto the left.

239.270

Threading the Bobbin Case

Hold the fully wound bobbin between thethumb and forefinger of the right hand with thethread end running over the top toward the right,as shown in figure 9-14, view A. With the left

239.271Figure 9-14.—Threading the bobbin case.

9-11

hand, hold the bobbin case as shown, with thethread slot near the top.

Place the bobbin into the bobbin case and pullthe thread into the slot in the edge of the bobbincase (view B). Draw the thread down under thetension spring and into the delivery eye at the endof the tension spring (view C). When the free endof the thread is pulled, the bobbin will rotateclockwise if the bobbin case has been threadedproperly.

Replacing the Bobbin Case

Hold the latch open on the threaded bobbincase with the thumb and forefinger of the lefthand, with the latch in a horizontal position. Placethe bobbin case on the center stud of the shuttlebody. Release the latch and press the bobbin caseback until the latch catches the groove near theend of the stud.

Preparing for Sewing

With the left hand, hold the end of the needlethread, leaving it slack from the hand to theneedle. Turn the balance wheel toward you untilthe needle moves down and catches the bobbinthread. Continue to turn the balance wheelforward until the needle comes up and brings thebobbin thread up with the needle thread.

With the thread take-up lever at its highestposition, lay both threads back under the presserfoot .

Commencing

Place thepresser foot,

to Sew

edge of the material beneath thelower the presser foot, turn the

balance wheel by hand until the needle is in thematerial, and press lightly on the treadle. Toprevent fouling the needle thread in the bobbincase, hold the ends of both threads until the firstfew stitches are made.

While sewing, hold the work flat, but do notpull or push on the material. Let the feed dogcarry the work evenly under the presser foot andneedle. If the operator pulls on the material, theneedle bends, strikes the throat plate, and is eitherdulled, or more likely, broken. When the needleis about to cross a seam or other unusually thickor uneven place in the work, disengage the clutch,and hand-turn the machine over the rough place;otherwise, the needle may be broken or thrownout of time.

239.272Figure 9-15.—Adjusting the machine thread tension.

Regulating the Tension

The tension on the needle thread should beregulated only when the presser foot is down. Ifthe tension of the machine thread is not correct,it should be adjusted by turning the tensionadjusting nut, as shown in figure 9-15. ToINCREASE THE TENSION, turn the nutclockwise; to DECREASE THE TENSION, turnthe nut counterclockwise.

The tension on the bobbin thread is regulatedby the small screw in the bobbin case tensionspring. To increase the tension, turn the screwclockwise; to decrease the tension, turn the screwcounterclockwise.

This screw is very small and is easily lostif extreme care is not exercised in backingit out when the tension is decreased. If thescrew is tightened excessively or is slightlytoo long, it will penetrate into the insideof the bobbin case and prevent removal of thebobbin.

When the tension on the bobbin thread hasbeen properly adjusted for a particular size ofthread, it is seldom necessary to change it. Acorrect stitch can usually be obtained by varyingthe tension on the needle thread, which is an easieradjustment.

9-12

239.273Figure 9-16.—Properly and improperly adjusted tensions.

For ordinary stitching, the needle and bobbinthreads should be locked in the center of thethickness of the material, as shown in figure 9-16,view A. When adjusting the tensions, you will nothave a cross section of the stitch.

If the tension on the needle thread is too tight,or if the bobbin tension is too loose, the threadwill lie straight along the upper surface of thematerial and appear as small loops, as shown infigure 9-16, view B.

If the tension on the bobbin thread is too tight,or if tension on the needle thread is too loose, thebobbin thread will lie straight along the undersideof the material, as shown in figure 9-16, view C.

Regulating the Length of a Stitch

The length of a stitch can be checked at thetime the tension of the stitch is checked, as a trialrun of stitches is necessary during bothprocedures.

The length of a stitch is regulated by thethumbscrew in the slot on the front of the upriseof the machine. To LENGTHEN the stitch,loosen the thumbscrew and move the leverDOWN. To SHORTEN the stitch, loosen thethumbscrew and move the lever UP. When thedesired length of stitch has been obtained by testrunning the machine on scrap material, tightenthe thumbscrew.

Regulating the Pressure on the Material

Pressure on thepressure-regulating

material is regulated by thethumbscrew on top of the

machine face. To increase the pressure, turn thethumbscrew clockwise. The pressure should bejust heavy enough to enable the feed dog to movethe work along evenly.

Removing Work

Hand-turn the balance wheel toward you untilthe thread take-up lever is at its highest position.Raise the presser foot, either by the hand leveror by the knee lift, and draw the work and threadsstraight behind the presser foot. Cut the threadsclose to the material, leaving free about 2 inchesof bobbin and machine thread.

Adjusting the Thread Take-up Spring

The thread take-up spring (fig. 9-15) shouldbe set so that when the eye of the needle reachesthe material on the downward stroke of the needlebar, the spring will be through acting on thethread, and will rest against the stop of the threadtake-up spring regulator.

If the thread take-up spring is not correctlyset, loosen the setscrew (2) in the arm of themachine and turn the tension adjusting stud tothe right for more movement of the spring, or tothe left for less movement. When the spring iscorrectly set, retighten the setscrew.

The tension on the thread take-up springshould be just sufficient to take up the slack ofthe needle thread until the eye of the needlereaches the material on its descent. To increasethe tension on the thread take-up spring, loosenthe tension adjusting stud and move the take-upspring from the recess in the regulator to the rightbetween the regulator and the tension disks. Whenthe required tension is obtained, securely tightenthe tension adjusting stud and move the springback into its position in the regulator recess. Todecrease the tension, move the spring to the leftbetween the regulator and the tension disks.

SINGER SEWING MACHINE 7-33

The class 7-33 sewing machine is a lockstitchheavy duty machine, and is intended for use insewing heavy canvas, webbings, and othermaterial not adaptable to the lighter duty sewingmachines. The only difference between the 7-31and the 7-33 is that the 7-33 has the clutch on themotor, while the 7-31 has the clutch on the balancewheel. The operation and maintenance techniquesare identical. The procedure for operating the 7-33sewing machine is the same as for the 31-15 sewingmachine.

9-13

As on any Singer sewing machine, the balance constant use. Use a castor base oil aswheel of the 7-33 should always turn toward the recommended by the manufacturer.operator.

Needles and ThreadLubrication

The procedure for ordering needles is the sameThe 7-33 machine is oiled at all the oiling for the 7-33 machine as for the 31-15 sewing

points shown in figures 9-17 and 9-18. The machine. Refer to table 9-2 for the relative sizesmachine should be oiled twice daily when it is in of needles and thread.

Figure 9-17.—Oiling points at the front of the 7-33 sewing machine.

Figure 9-18.—Oiling points at the back of the 7-33 sewing machine.

9-14

239.274

239.275

Table 9-2.—Relative sizes of needles and thread

Setting the Needle

The same procedure may be followed with thismachine as for the 31-15 sewing machines.

Threading the Machine

Turn the balance wheel toward you until thethread take-up lever (7) moves up to its highestposition (fig. 9-19). Pass the thread from thethread stand to the thread post, right to left

through the bottom hole, then right to leftthrough the top hole. Pass the thread through thetwo thread guides (1) and (2). Continue thepassage of thread between the retainer disks (3),down and under the tension disks (4). Pass thethread into the loop of the thread take-up spring(5), under the wire loop (6), up, and from backto front through the hole in the thread take-uplever (7). Now pass the thread down through thethread guide (8), into the slot in the vibratingpresser bar (9), and on down through the thread

239.276Figure 9-19.—Threading the 7-33 sewing machine.

9-15

guide (10), which is located on the needle clamp.The needle is now threaded from left to rightthrough the eye of the needle (11). After the needleis threaded as shown in figure 9-19, pass thethread down through the hole in the lifting presserfoot (12). Draw about 4 inches of thread throughthe hole in the lifting presser foot with which tobegin sewing.

Notice that the lubricating cup has beenbypassed. No lubricant is used on the threads andcords used in the manufacture or repair ofparachutes.

Removing the Bobbin

Turn the balance wheel forward to bring theneedle bar and thread take-up lever to its lowestposition. With the aid of the shuttle opening toolor a small screwdriver, insert the blade end in theslot in the spring latch beneath the shuttle cylinder(fig. 9-20). Press the latch away from the cylinderand it will swing out. The bobbin will then slideout of the shuttle cylinder.

Winding the Bobbin

Place the bobbin on the bobbin winder spindleand push it up closely against the shoulder. Thesmall pin in the shoulder must enter the slot inthe bobbin.

Pass the thread from the thread stand throughthe hole in the left side of the bobbin from theinside. Push the bobbin winder pulley up againstthe balance wheel, and place the bobbin winder

Figure 9-20.—Removing the bobbincylinder.

239.277from the shuttle

239.278Figure 9-21.—Replacing the bobbin.

latch in position. Raise the presser foot and startthe machine. The end of the thread should be helduntil a few turns are wound on the bobbin toprevent slipping. When sufficient thread has beenwound on the bobbin, the bobbin winder will stopautomatically.

Replacing the Bobbin andThreading the Shuttle

Take the bobbin between the thumb andforefinger of the left hand, as shown in figure9-21. The free end of the thread should be drawnoff from the underside toward the right. Place thebobbin in the shuttle cylinder as far as it will go.Draw the thread into the slot in the cylinder andunder the tension spring into the delivery eye.Push the shuttle cylinder in until it is locked bythe spring latch. There should be about 3 inchesof thread hanging free from the shuttle with whichto begin sewing.

Regulating the Tension

The tension on the needle thread is regulatedby the thumb nut at the front of the threadretainer disks. The tension on the thread retainerdisks should be just enough to cause the tensionwheel to turn when the thread is taken from thespool.

The tension on the bobbin thread is regulatedby the small screw that holds the tension springto the shuttle cylinder. To increase the tension,

9-16

turn the screw clockwise. To decrease the tension,turn the screw counterclockwise.

The tension on the machine and bobbinthreads should be checked by test-running a rowof stitches on scrap material. The lockstitchshould lock in the center of the material, asdescribed for the 31-15. When sewing webbingswith the 7-33 sewing machine, the specificationsfor webbing sewing should be checked todetermine at what ply of the webbing the stitchshould lock.

Regulating the Length of Stitch

The procedure for regulating the stitch onthe 7-33 ‘sewing machine31-15.

Regulating the Pressureon the Material

is the same as for the

The pressure on the material is regulated bymeans of the hexagon head screw (1). (See figure9-22.) Loosen the hexagon head locknut (2) andturn the adjusting screw clockwise to increase thepressure, or counterclockwise to decrease thepressure on the spring (3). When the desiredpressure has been obtained, hold the adjustingscrew with a wrench to keep it from turning while

239.279Figure 9-22.—Regulating the pressure on the material.

9-17

the locknut is being tightened against the bracket(4).

The pressure should be just heavy enough toenable the feed dog to move the work alongevenly, and to prevent the work from rising withthe needle.

Preparing the Sewing

The same sewing preparatory procedures areused for the 7-33 as for the 31-15 sewing machine,except there is no knee lifting device. The handpresser bar lifter is the only device provided forlifting the presser foot on the class 7-33 sewingmachine.

Removing the Work

Stop the machine and raise the thread take-up lever to its highest position. Draw about 3inches of thread through the thread retainingdisks. Raise the presser foot and draw the workback, cutting the threads close to the material.Leave the ends of the threads under the presserfoot .

Modification of PresserFoot for Webbing Sewing

The modification of a presser foot is illustratedin figure 9-23. The presser foot should be cut

239.280Figure 9-23.—Modification of presser foot for webbing

sewing.

along the dotted line, removing the right portionof the foot. After cutting, the edges should be fileddown to a smooth round finish.

Parachute harness and webbing sewing isclassified as a major repair. However, there arevarious other sewing projects requiring webbingsewing.

ROTARY SEWING MACHINES

Some of the most commonly used rotarysewing machines are the class 111 W series.They are the type used to teach basic sewing inPR “A” school, and can be found in almost anyPR shop.

CLASS 111 SEWING MACHINES

The class 111 sewing machines are one line(single needle) lockstitch machines designed to sew

medium weight and heavyweight material. Theyare capable of sewing at a speed of approximately3,000 stitches per minute (spin). The lockstitch isformed in the bobbin assembly by the rotary hookon the 111 machines. The class 111 machine iscommonly used for sewing aircraft protectivecovers, upholstery, and soundproofing.

DIFFERENT MODELS OF THE111 W SEWING MACHINE

The following text discusses the variousmodels of the 111 W sewing machine.

111 W 150 Sewing Machine

The 111 W 150 sewing machine is ahigh-speed, single-needle, lockstitch, compoundfeed machine employing a gear-driven rotaryhook with a vertical axis. It is designedfor sewing medium weight fabrics such as

239.281Figure 9-24A.—Class 111 sewing machine, front view showing oiling points.

9-18

flight clothing, nylon, twills, and lightweightcanvas.

111 W 151 Sewing Machine

The 111 W 151 sewing machine is also a single-needle, lockstitch, rotary hook machine, intendedfor high-speed straight stitching of medium heavymaterials.

The 111 W 151 sewing machine differs fromother models of the class 111 machines in that ithas a single presser foot instead of the alternatingpresser foot.

111 W 152 Sewing Machine

The 111 W 152 sewing machine is a single-needle, lockstitch, compound feed machine witha vertical axis sewing hook. This machine hasalternating pressers with a 3/8-inch lift. It has asafety clutch that prevents the hook from beingdamaged or getting out of time due to accidentalstrain.

111 W 153 Sewing Machine

The 111 W 153 sewing machine is similar tothe 111 W 152, but it is used for sewing heavywork such as automobile and truck upholstery,tents, awnings, and leather flight jackets.

111 W 154 Sewing Machine

The 111 W 154 sewing machine is also similarto the 111 W 152, but its alternating pressers havea lift of 1/2 inch, and the machine is designed forstitching upholstery work, leather coats, andbinding heavy materials such as felt padding.

111 W 155 Sewing Machine

The 111 W 155 sewing machine is similar tothe 111 W 154 except that its minimum stitchesper inch is 3 1/2, and it has an adjustable liftingeccentric for instantly setting the alternatingpressers to the minimum amount of lift requiredfor the work to be sewn.

FUNCTIONAL FEATURES

The oiling parts for class 111 sewing machineare shown in figure 9-24A. Figure 9-24B identifies

239.448Figure 9-24B.—Class 111 sewing machine, front view showing components and parts.

9-19

the component parts. The primary feature of eachcomponent is explained in the following text:

Lifting Presser Bar Tension RegulatingScrew. Regulates the pressure on the alternatingpresser foot.

Feed Indicating Disc. Indicates the numberof stitches per inch which are being made by themachine.

Balance Wheel. Provides a connectionbetween the driving unit and the sewing machinehead.

Arm-and-Hook Driving Shaft ConnectionBelt. Connects the upper arm shaft with the hookdriving shaft.

Feed Dog. Feeds the material from theunder side.

Rotary Hook Assembly. Contains themechanism that forms the lockstitch by using theneedle and bobbin threads.

Bobbin. Contains the lower thread used informing the lockstitch.

Bobbin Case Retainer Hook Gib. Holdsthe bobbin case in the bobbin race.

Needle-deflecting Hook Washer. Deflectsthe needle so the rotary hook will not strike theneedle.

Throat Plate. Surrounds the feed dog andkeeps the material from slipping after the feed doghas been adjusted to the proper height.

rotaryplate.

Bed Slides. Covers the feed eccentric andhook assembly on each side of the throat

Feed Indicator Plunger. Used inconnection with the feed indicator to regulate thenumber of stitches per inch desired.

Safety-clutch Lock Stud. Re-engages theneedle with the hook driving assembly afterclearing a thread jam.

Bobbin Case Opener. Prevents threadfrom jamming underneath the throat plate on thebobbin case base.

9-20

239.449Figure 9-25A.—Class 111 sewing machine, side view.

Rotary Hook Saddle Complete. The rotaryhook is operated by the spiral driving pinion gear,which, in turn, is operated by the hook drivinggear located on the hook driving shaft.

Rotary Hook and Connection Belt TimingPlate and Arrows. Used to time the arm shaft withthe hook driving shaft.

The following parts are shown in the side viewof the Class 111 sewing machine (figures 9-25Aand 9-25 B).

Thread Take-up Lever. Pulls the needlethread against the tension disc after the lockstitchis formed at the rotary hook and pulls suffi-cient thread from the spool to make the nextstitch.

Vibrating Presser Bar Tension RegulatingScrew. Regulates the pressure on the presser foot.Only sufficient pressure tosecurely is needed.

hold the material

Face Plate. Coversmechanism of the two pressel

and protects thefeet and needle bar.

Vibrating Presser Foot. Holds the materialin place while the alternating presser foot rises to

239.282Figure 9-25B.—Class 111 sewing machine, side view

showing oiling points.

Needle Thread Lubricator. Lubrication ofthe thread when sewing leather. Lubrication ofthe thread prevents it from fraying, and preventsthe needle from becoming hot when sewing at highspeed.

Needle Thread Tension. Regulates thetension on the needle thread so that the lockstitchmay be adjusted properly.

Needle Thread Controller Spring As-sembly. Removes sufficient slack from theneedle thread when the needle is descend-ing to prevent the needle from splitting thethread.

Needle Bar. Holds the needle and carriesthe thread to the rotary hook where the lockstitchis formed.

make another stitch.

Lifting Presser Foot. Holds the materialin place while the vibrating presser foot and feeddog go forward to get material for the next stitch.

The class 111 machine is a compound feedmachine. This means that the feed dog, vibratingpresser foot, and needle move together to feed thematerial. Some class 111 machines are equippedwith a compound feed only, such as the 111 W151; and others are equipped with a combinationof the compound feed and alternating presser footthat holds the material while the needle andvibrating presser foot are moving into position forthe next stitch, such as the 111 W 155.

Perhaps the description of the feed mechanismgave you a hint that the class 111 sewing machineis a more complicated machine than the class 31.It is indeed.

Timing the 111 W ClassSewing Machines

The first step in timing the 111 W machine isto set the feed driving eccentric on zero stitchesper inch (0 spi). Set the needle bar. With the needlebar in its lowest position (needle bar crank in thehorizontal position, the rounded portion on thetop and driving stud at the bottom), theconnecting link will be vertical. Set the needle barwith the upper timing mark just visible at the baseof the needle bar rock frame, and tighten theneedle bar pinch screw. The needle bar is thenproperly set.

To set a needle bar that has no mark, set thefeed eccentric for eight stitches to the inch. Thenset the needle bar so that when it rises 3/32 inchfrom its lowest position and the point of thesewing hook is at the center of the needle, theneedle eye will be about 1/16 inch below the hookpoint.

The next step is to time the arm shaft with thehook drive shaft. With the connection beltremoved, rotate the balance wheel toward theoperator until the thread take-up lever is at itshighest point, then aline the arrow on the hookdrive shaft collar with the timing plate arrow, andreplace the connection belt. Rotate the balancewheel and check. The next step is to center thefeeding action. For this step the feed drivingeccentric must be set on zero spi. With the needleentering the feed dog, center the needle in the hole

9-21

in the feed dog with a distance of 17/32 inchbetween the needle bar and the presser bar.

In centering the feeding action, the followingsequence should be followed: Hold the needlecentered in the feed dog with a 17/32-inchspacebetween the needle bar and presser bar. Tightenthe feed driving crank and feed driving rockshaftcrank pinch screws, making sure that the crankis flush with the end of the feed driving rockshaftand parallel with the bed. Next, tighten the needlebar rock frame rockshaft crank pinch screw in theback of the uprise. The shank of the presser footis 17/32 inch wide and may be used for measuringthe space.

The next step is to set the sewing hook to orfrom the needle. This is done by moving the hooksaddle left or right as necessary; the hook shouldpass the needle as closely as possible withouttouching. When this is done, retighten the hooksaddle screws. Next, set the sewing hook with theneedle. With the needle bar on the upstroke, thelower timing mark on the needle bar should bejust visible at the base of the needle bar rockframe. Set the point of the sewing hook in thecenter of the needle 1/16 inch above the eye. Toadvance the sewing hook, move the hook drivegear to the right; and to retard, move the hookdrive gear to the left.

NOTE: The first screw in the hook piniongear and the second screw in the hookdrive gear are splined screws. The hookdrive gear must be centered in relation tothe sewing hook shaft at the bottom of thehook saddle. “

Lubrication of The Class 111Sewing Machines

Figures 9-24A, 9-25B, and 9-26 show thevarious lubrication points on class 111 sewingmachines. Oiling points are indicated by theunnumbered arrows. Familiarization with thenomenclature of the machines may also beaccomplished by studying these illustrations.

To lubricate the class 111 machine, swing backthe top cover and oil the bearings, then replacethe cover.

Loosen the thumbscrew in the upper end ofthe faceplate, turn the faceplate upward, and oilthe wick and bearings, as shown in figure 9-25B.After oiling, turn down the faceplate and tightenthe thumbscrew.

Turn the machine back on its hinges and applyoil at the places designated by the arrows in figure9-27. All contacting parts on the bottomside ofthe machine should also be oiled.

To lubricate the hook, remove the bed slideand place oil in the oil well (fig. 9-26). This

Figure 9-26.—Rear of machine, showing oiling points.

9-22

239.284Figure 9-27.—Base of machine, showing oiling points.

lubricates the upper hook bearing and themechanical opener mechanism.

The small, green felt pad on the side of thebobbin case should be kept wet with oil tolubricate the hook race. When this pad is wet, itappears nearly black; when it appears light green,it indicates that it is dry. When a machine is new,oil should be applied to this felt pad EACH TIMEA BOBBIN IS REPLACED.

Needles and Thread

The thread used on rotary sewing machines isleft twist. To determine the twist of thread, referto f igure 9 -28 .

Table 9-3 lists the class and variety of needlesand the needle size range for each of the class 111machines.

239.267Figure 9-28.—How to determine the twist of thread.

The size of needle to be used is determined bythe size of the thread and material used. Thethread must pass freely through the eye of theneedle. If rough or uneven thread is used, or ifit passes with difficulty through the eye of the

Table 9-3.—Data for Class 111 Sewing Machine

9-23

needle, the machine will not function prop-erly.

Needles used on rotary sewing machines areordered the same way as those for oscillatingsewing machines.

The needles for rotary sewing machines haveseven parts. This is one more part other than theneedles for the oscillating machines. Theadditional part is the SCARF, which is a smallindention just above the short thread groove. Thepurpose of the scarf is to permit the point of thesewing hook to come close enough to pick up theneedle thread without striking the needle.

Operation

Operation of rotary sewing machines is thesame as for the oscillating sewing machines.

Setting the Needle

Turn the balance wheel toward you until theneedle bar moves up to its highest position.Loosen the setscrew in the needle bar and slip theneedle up into the bar as far as it will go. Theneedle must be inserted with its long thread groovetoward the left, the eye of the needle being directlyin line with the machine bed. Retighten thesetscrew.

Threading the Machine

Pass the thread from the thread stand fromback to front (fig. 9-29) through the lower hole(1) in the thread post on top of the machine, thenfrom right to left through the upper hole (2) inthe post. Pass the thread down through hole (3),up through hole (4), and down through the hole(5) in the thread guide on the front of the machine.Continue the thread over from right to leftbetween the tension disks (6), and down, fromright to left, around the thread controller (7).Then the thread should go up into the fork (8)in the thread controller disk against the pressureof the wire controller. The thread is then passedup through the thread guide (9), and from rightto left through the hole in the thread take-up lever(lo).

Pass the thread down through the thread guide(11), and between the felt pad and the felt padretainer finger (12). (If the machine you arethreading does not have the felt pad and retainer

239.285Figure 9-29.—Threading the class 111 sewing machine.

finger installed, bypass this component.) Finishthe threading by passing the thread down throughthe thread guide (13), through the thread guide(14) at the bottom of the needle bar, and fromleft to right through the eye of the needle (15).Always thread a needle toward the bobbin.

Removing the Bobbin

To remove the bobbin, draw out the right-hand slide plate in the bed of the machine. Insertthe fingernail of the forefinger under the latch;raise the latch and lift the bobbin out. (See figure9-30).

9-24

239.236Figure 9-30.-Bobbin case threaded.

Winding the Bobbin

To wind the bobbin and adjust the bobbinwinder, follow the procedure given for the 31-15sewing machine.

Replacing the Bobbin and Threadingthe Bobbin Case

Hold the bobbin between the thumb andforefinger of your right hand with the threaddrawn out on the bottom from left to right. Placethe bobbin on the center stud of the bobbin case;then push down the latch.

Draw the thread into the slot (1), and underthe back of the projection (2). Leave a loose endof thread about 2 inches long above the slide.When closing the slide plate, leave just enoughspace for the thread to pass through when it isfirst picked up by the needle.

Regulating the Tension

The tension on the needle thread is regulatedby the tension thumb nut located at the front ofthe tension disks on the front of the machine. Toincrease the tension, turn this thumb nutclockwise. To decrease the tension, turn thethumb nut counterclockwise.

The tension on the bottom (bobbin) thread isregulated by means of the small screw nearest the

center of the tension spring in the outside of thebobbin case (l), as shown in figure 9-30. Toincrease the tension, turn this screw clockwise. Todecrease the tens ion , turn the screwcounterclockwise.

Regulating the Length of Stitch

The number of stitches per inch is stamped onthe stitch indicating disk, which can be seenthrough the hole on the uprise.

To change the length of stitch, press down thefeed regulating stud (plunger), located in the bedof the machine. At the same time, turn the balancewheel slowly until the plunger enters a notch inthe adjustable feed eccentric disk. Continue tohold the plunger and turn the balance wheelforward or backward until the number of stitchesper inch desired can be seen through the hole inthe front of the uprise. Disengage the plunger byreleasing it.

Regulating the Pressureon the Material

The pressure on the material is regulated bythe presser bar regulating screw at the back of thesewing machine. The screw acts on a flat spring.To increase the pressure, turn this screwdownward. To decrease the pressure, turn thisscrew upward. The pressure should be only heavyenough to enable the feed to move evenly alongwhatever thickness of material you are using.

Preparing for Sewing

With the left hand, hold the end of the needle(machine) thread, leaving it slack from the handto the needle. Turn the balance wheel over towardyou until the needle moves down and up againto its highest position. If the sewing machine isproperly timed, this will bring the bobbin threadup with the machine thread through the hole inthe feed dog. Lay the threads back under thepresser foot and close the slide.

Place the material under the presser foot.Lower the presser foot either by hand or by theknee lift, and begin to sew. Start the sewing byturning the balance wheel over toward you as youdepress the treadle.

Removing the Work

After the machine has stopped, move thethread take-up lever to its highest position. Raise

9-25

240.80Figure 9-31.—The 211 W 151 sewing machine.

the presser foot, draw the work back, and cut thethreads close to the material. Lay the ends of thethreads back under the presser foot.

SINGER SEWING MACHINE211 W 151

This machine performs the same functions asthe 111 W 151. It is a newer model, morestreamlined and modern in appearance, and hassome design features not found in the 111 W 151machine. (See figure 9-3 1.) These features includea new lubrication system, a thread take-up leverguard, a thread lubricator, and a new stitchindicator.

The 211 W 151 sewing machine is a high-speed(4,000 rpm maximum), single-needle, lockstitch-type machine, designated for sewing medium toheavyweight fabrics. It is belt-driven and has arotary hook on a vertical axis, which makes tworevolutions for each stitch.

It has a safety clutch (fig. 9-32) that isadjustable to suit the sewing conditions; thisprotects the sewing hook from damage. If thehook is obstructed by foreign matter, the clutchwill disengage and re-engage only after the areahas been cleared. The feeding mechanism is acompound drop and needle feed with the longeststitch at five stitches per inch.

240.81Figure 9-32.—Safety clutch and lower belt pulley.

Other features of the machine include a hingedpresser foot, a presser bar lift of 1/4 inch, a needlebar stroke of 1 5/16 inches, a bed that is 20 3/8inches long by 7 inches wide, and a space of 101/2 inches to the right of the needle.

Needles

The needles used in this machine varyaccording to the clearance under the presser foot.

9-26

Use 135 x 7 needles with machines set with1/4-inch clearance under the presser foot, and135 x 17 needles with those set with 3/8-inchclearance (lift).

Adjustments

Adjustments to the 211 W 151 are basicallythe same as for 111 W 151. These adjustmentsare discussed in the following text.

SETTING THE NEEDLE BAR.— Place theneedle bar up into the needle bar holder as faras possible. Hold in this position and turn thebalance wheel toward the operator until the needlebar is at its lowest position. When in this position,set the bar so the upper timing mark is just visiblebelow the needle bar frame, and tighten the needlebar connecting stud pinch screw.

In case the needle bar does not have timingmarks, set the machine to zero stitches per inchand place the needle bar up in the holder as faras possible. Turn the balance wheel by hand untilthe bar is at its lowest position. After reachingthe lowest position of the needle bar, continueturning the balance wheel toward the operatoruntil it reaches 3/32 inch above its lowest point,then set the eye of the needle 1/16 inch below thepoint of the sewing hook.

SETTING THE NEEDLE.— To set the nee-dle, insert the needle shank as far as possible intothe needle bar with the long groove of the needleto the left and tighten the screw. (See figure 9-33.)

240.82Figure 9-33.—Setting the needle.

240.83Figure 9-34.—Needle bar rock frame rockshaft damp screw.

RELATIVE POSITION OF’ NEEDLE BARAND PRESSER BAR.— To set the relativeposition of the needle bar to the presser bar,loosen the needle bar rock frame rockshaft clampscrew, which is located behind the cover plate onthe front upright position of the arm (fig. 9-34).Set the needle bar so the distance between theneedle bar and presser bar is 17/32 inch. Retightenthe clamp screw.

NOTE: A handy tool for this adjustmentcan be manufactured locally from a thinpiece of metal stock filed to exactly17/32-inch width. This gauge should beplaced between the two bars while theclamp screw is being tightened. Thisenables the operator to keep pressure onthe loose needle bar.

ADJUSTMENT HEIGHT OF SEWINGHOOK.— Before attempting to adjust theheight of the sewing hook, it is necessary tomake a feeler gauge for testing the height.This gauge can be made of 0.032-inch shim stock,or a regular feeler gauge can be cut or trimmeddown so it will fit in the small groove in thethroat plate, which retains the bobbin case stopfinger.

If, after testing, the hook height isunsatisfactory, turn the balance wheel so the twosetscrews in the bottom of the hook are accessible;loosen them with an Allen wrench. Remove thecloth washer from the bobbin case and turn thehook until the height adjusting screw is directly

9-27

239.450Figure 9-35.—Timing tbe sewing hook.

under the hole in the bobbin case. (See figure9-35.) Turn the screw into raise the hook, andout (while pressing down on the hook) to lowerit. The gauge should barely pass between thethroat plate and bobbin case stop finger.Retighten the Allen setscrews and turn theadjusting screw in so that a slight tension is lefton the screw.

SETTING SEWING HOOK TO OR FROM NEEDLE.— To set the relative position of the

hook saddle to the needle, loosen the hook saddleadjusting screws (fig. 9-36) and slide the hooksaddle to the right or left, as necessary, to set thepoint of the hook as close to the needle as possible(without actually touching). After setting the hooksaddle, check the clearance between the hookdrive gear and the face of the hook saddle. Thisclearance should be 0.008 inch; if it is not, resetit by loosening the screw and setscrew in the hookdrive gear, and move the gear to the right or leftto get the proper clearance.

TIMING BOBBIN CASE OPENER.— To setthe bobbin case opener, turn the balance wheeltoward the operator until the lower timing markon the needle bar is barely visible below the needlebar frame on its upward stroke. Tip the machineback and loosen the two Allen screws in thebobbin case opener drive gear; then line up thetiming marks by turning the opener shaft with ascrewdriver. The timing marks are located asfollows: one on the flange of the opener, and theother on the hook saddle (fig. 9-35). Adjust theopener so it lightly touches the bobbin case andturns it enough to make a sufficient opening fora free passage of thread between the bobbin casestop finger and the throat plate. Tighten thescrews in the bobbin case opener drive gear.

RAISING OR LOWERING THE FEEDDOG.— To raise or lower the feed dog, remove

240.85Figure 9-36.—Hook saddle assembly showing bobbin case raceway oil reservoir.

9-28

the throat plate and clean all lint and dirt frombetween the grooves and teeth of the feed dog.Tip the machine back and turn the balance wheeltoward the operator until the feed dog is in itshighest position. Loosen the screw in the feedlifting cam fork and raise or lower the dog asdesired; then retighten the screw. A properly setfeed dog will show a full tooth above the throatplate when at its highest position.

After adjusting the feed dog, check tosee that the needle is properly set in thehole in the feed dog. If adjustment isneeded, loosen the pinch screws in the feeddriving rock frame, and set the needle sothat when it is all the way down, it willbe slightly forward of center in the hole.Retighten the pinch screws. The feed adjust-ment points are illustrated in figure 9-37.

ADJUSTING FEED ECCENTRIC.— Thefeed eccentric (fig. 9-38) may occasionally needadjustment to remove play caused by wear of thegib, or by looseness between the feed eccentricand the eccentric body. To adjust the gib,loosen the two locking screws, then turninward on the adjusting screws until all playis eliminated and the eccentric fits in the slotproperly.

240.86Figure 9-37.—Feed adjustment for the 211 W 151 sewing

machine.

240.87Figure 9-38.—The feed eccentric.

CAUTION

L OCKI NG SCRE WS MUST BELOOSENED BEFORE ATTEMPTINGTO LOOSEN ADJUSTING SCREWS.RETIGHTEN THE LOCKING SCREWSAFTER ADJUSTMENT IS MADE.

The feed eccentric collar may be moved to theright or left to change spring tension, but it isordinarily set flush with the hub of the eccentricbody.

CHANGING THE LENGTH OF THESTITCH.— TO change the length of stitch, stopthe machine. Turn the balance wheel, by hand,toward the operator until the button drops(clicks), then turn the machine pulley until thenumber representing the desired stitches per inchis lined up properly and then release the button.

CAUTION

DISENGAGE THE BUTTON BEFOREATTEMPTING TO SEW. DO NOTENGAGE THE BUTTON WHILE THEMACHINE IS IN OPERATION.

Removing Components

To remove the hook, takeoff the presser foot,throat plate, and feed dog; then loosen the two

9-29

Allen screws in the hub of the hook and lift thehook off the hook shaft. To remove the bobbincase from the hook assembly, loosen the hook gibscrews, lift off the gib, and then lift out the bobbincase.

Removing the Arm ShaftConnection Belt

When the arm shaft connection belt isdisconnected for any reason, the machine will becompletely out of time. Therefore, the needleshould be removed before removing the belt toprevent damage. To remove the belt, slide it offthe lower belt pulley, loosen the screws in the

machine pulley, and remove the pulley and ballbearing, which come out through the end of thearm.

Replace the belt by reversing this procedure.Remove the end play from the shaft by lightlysetting the setscrews and tapping the balance wheelinto position with the palm of the hand and thensecurely setting the setscrews. Place the belt overthe upper belt pulley and line up the timing markson the lower belt pulley and on the bed of themachine. While holding the lower belt pulley inposition, turn the balance wheel toward theoperator’s position until the thread take-up leveris at its highest position, then slide the belt ontothe lower belt pulley. The arm shaft connectionbelt and the lower belt pulley are illustrated withthe safety clutch in figure 9-32.

CAUTION

D O N O T T A M P E R W I T H T H ESAFETY CLUTCH. ITS TORQUE ISPRESET AT THE FACTORY.

Lubrication

The hook saddle is equipped with an oilreservoir (fig. 9-36), which contains oil to bepumped to the bobbin case raceway. The flow ofthis oil is controlled by a control valve screwlocated just aft of the bobbin case opener in thehook saddle. For more oil, turn the valve screwclockwise; counterclockwise for less oil.

CAUTION

DO NOT ADJUST FLOW OF OILWITHOUT FIRST LOOSENING THE

LOCKING SCREW LOCATED ON THESIDE OF THE HOOK SADDLE JUSTABOVE THE CAM SHAFT GEAR.AFTER ADJUSTING THE CONTROLVALVE SCREW FOR PROPER FLOW,RETIGHTEN THE LOCKING SCREW.

SINGER SEWING MACHINE143 W 2 AND 3

This type of machine is not as common asthose previously described, but it has unlimiteduses in the repair and maintenance of parachutesand survival equipment.

The 143 W 2 is a high-speed sewing machinethat has an aluminum alloy vibrating needle barframe and a rotary hook. It is intended foroverseaming and zigzag stitching on fine andgeneral fabrics and lightweight leather. It has ballbearings on the rear end of the arm shaft andhook driving shaft. The needle bar has amaximum throw of 3/16 inch, vibrating both sidesof a centerline.

The 143 W 3 sewing machine is similar to the143 W 2 except that the needle has a maximumthrow of 5/16 inch.

The maximum speed recommended formachine 143 W 2 is 3,500 stitches per minute, andfor machine 143 W 3, 3,000 stitches per minute,the speeds depending on the material being sewn.

Needle and Thread

The needles forsewing machines are

the 143 W 2 and 143 W 3of class and variety 135 x 7;

the sizes from 7 to 24.

Left twist thread should be used on thesemachines. To make a smooth even stitch with thesewing machine, use good, firmly twisted andsmoothly finished thread. The thread should passfreely through the eye of the needle.

Setting the Needle

Push the needle up in the needle bar as far asit will go, with the LONG THREAD GROOVETO THE FRONT, and secure it firmly with thesetscrew. It may be necessary to turn the needleslightly to the right or left for some threads ifstitches are missed.

9-30

Bobbin and Bobbin Case

The procedure for removing the bobbin case,winding the bobbin, threading the bobbin case,and replacing the bobbin case is the same as forthe 31-15 sewing machine. The only exception tothis is that when the bobbin case is threaded, thethread should be drawn from the BOTTOM fromleft to right, instead of from the top as given forthe 31-15.

Threading the Needle

These machines are threaded in the same wayas the 111 series machines, described earlier in thechapter. When threaded up to the needle, threadthe needle from the front through the eye to theback. The long thread groove should be in frontwhen the needle is properly set in the needle bar.

Regulating the Length of Stitch

To adjust the length of stitch, depress thestitch regulator lever (fig. 9-39) on the uprise and,at the same time, turn the balance wheel forwarduntil the lever engages in the notch in the stitch

regulator flange. Hold the lever in the notch andturn the balance wheel backward or forward (asnecessary) until the desired number of stitches perinch is shown opposite the arrow on the stitchregulator.

Regulating the Width of the Zigzag

The extreme width of the zigzag (needle throw)on the 143 W 2 is 3/16 inch; it is 5/16 inch onthe 143 W 3. The width of bight is regulated byturning the knurled knob on the needle vibratorregulating spindle head (fig. 9-39) at the front ofthe machine. To increase the width of the stitch,turn the regulating spindle head to the left, andto the right to decrease.

Setting the Needle Bar

The two adjustment marks on the needle barare 3/32 inch apart. To set, insert the needle barup into the needle bar frame so the upper mark isjust visible at the lower end of the needle barframe with the bar at its lowest position. The eyeof the needle should be 1/16 inch below the point

239.293Figure 9-39.—Oiling points at the front of the 143 W 2.

9-31

of the hook, and the long thread groove towardthe operator.

Setting and Timing the Needle Bar Frame

Turn the regulating spindle head all the wayto the right. This will cause the machine to sewa straight stitch. The needle should be centeredin the hole in the throat plate. If not, loosen thesetscrew that holds the eccentric stud (1) and turnthe stud until it is centered (fig. 9-40.) Turn theneedle regulating spindle head (5) to the extremeleft for the widest throw. Turn the balance wheelforward until the needle is at its lowest position.The needle bar should start to move in a sidewardmovement as the needle starts to rise. If it doesnot, you must advance or retard the vibratorpinion gear (2), shown in figure 9-40.

Timing Sewing Hook

Turn the balance wheel toward the operator’sside until the needle bar is all the way down andhas risen until the lower timing mark is just visiblebelow the needle bar frame. Loosen the setscrews(10) in the lower belt pulley (fig. 9-41) and set thehook point to the center of the needle eye.Retighten the setscrews.

Setting the Hook DistanceTo or From Needle

Loosen the two hook shaft retaining screws(8) (fig. 9-41) and the two screws in the hookpinion gear (7), and slide the hook to the correctposition. Retighten the hook shaft retainingscrews. Set the gear in the proper place on theshaft—gear aligned with hook drive gear-and

240.92Figure 9-40.-X-ray view of zigzag sewing machine.

9-32

240.93Figure 9-41.—Adjustments in the bed of the machine.

retighten the two setscrews to hold the hook inposition.

Raising or Lowering the Feed Dog

The feed dog should show a full tooth abovethe throat plate when at its highest position. Toadjust the dog, remove the throat plate and makesure all lint, dirt, or other obstruction is removed,then replace the throat plate. Turn the balancewheel forward until the feed dog is at its highestposition; then loosen the feed dog adjusting screw(2) (fig. 9-41), and raise or lower the feed dog asrequired. Retighten the adjusting screw to holdthe feed dog in position.

To prevent the feed dog from striking eitherend of the slots in the throat plate, loosen thepinch screw (9) (fig. 9-41) and move the feed dogsforward or backward (as necessary) until thelongest stitch can be taken without striking thethroat plate.

Sewing Techniques

In this chapter we pointed out the need to letthe machine feed the material being sewn, and

other techniques to obtain a good seam.At first you will find it very difficult toturn comers when using a sewing machine. Ifyou will follow these instructions you will findit very easy to make a turn and not lose yourstitch.

Stop the machine while the needle isrising, but before it is out of the mate-rial, raise the presser foot and turn thework. This method uses the needle as apivot. When the material lies in the newposition, lower the foot and continue sew-ing.

Removing the Work

Raise the presser lifter and turn the machineby the balance wheel until the take-up leveris at its highest position. Draw the workout away from you. If the threads do notdraw out easily, the take-up lever is notin the right position. If the machine is stoppedas directed, the needle will not be unthreadedwhen you start to sew, even if only ashort end is left through the eye of theneedle.

9-33

Figure 9-42.-Consew 99R.

CONSEW 99R and 99R-3SEWING MACHINE

The Navy has recently acquired new modelzigzag sewing machines (fig. 9-42), model99R-3 is not shown, capable of the ropesewing needed to install the four-line releasesystem. Two models are available-the 99Rand the 99R-3. Both models are rotary hook-type machines. They are fairly conventionalmachines, and the operation of both is verysimilar to that of the machines we have alreadydiscussed.

Models 99R and 99R-3 machines are iden-tical in outward appearance; the differenceis in the type of stitch they make. In model99R, every successive stitch forms a sym-metrical zigzag pattern stitch, type 304. In

model 99R-3, aby successive pairs

Threading the 99R

zigzag patternof stitches, type

239.451

is formed308.

and 99R-3 Machines

Follow the instructions below when threadingthe needle and bobbin on the 99R and 99R-3sewing machines:

1. Turn the balance wheel toward you untilyou are able to position the needle so you canplace the thread through its eye. Remember,always thread the needle toward the bobbin. Inthis case. you run the thread from front toback.

2. Hold the loose end of the needle threadin your left hand, turn the hand wheel toward

9-34

you with your right hand until the needle movesdown and up again to its highest position.

3. Pull the needle thread gently and thebobbin thread will come up with it through thehole in the needle plate.

4. Place both ends of the thread beneath andin back of the presser foot.

5. With the needle at its highest point, placethe material to be sewn beneath the presser footand fully lower the presser foot lifter lever.

6. Start sewing.

Regulating the Tension

Tension is the key word to good sewing. Forperfect stitching, the tension of the upper andlower threads should be balanced and justsufficiently tight to lock both threads in the centerof the material (look again at figure 9-16).

The machine is correctly adjusted to make aperfect stitch before leaving the factory. Whenadjustments do become necessary, the problemis more likely to be caused by the upper threadtension, so always begin there. To adjust theupper thread tension, proceed as follows:

1. Lower the presser foot. Remember upperthread tension adjustments must be made with thepresser foot down.

2. Check the upper thread tension. If it isloose, turn the tension nut (A in fig. 9-43)

239.452Figure 9-43.—Upper thread tension.

clockwise to increase the tension; if the upperthread tension is tight, turn the tension nutcounterclockwise to loosen it.

Adjusting the Bobbin Thread Tension

When you find it necessary to adjust thebobbin thread tension, turn the tension screw(T of fig. 9-44) on the bobbin case clockwise toincrease the tension, and turn the screwcounterclockwise to decrease the tension.

Regulating the Pressureof the Presser Foot

The pressure of the presser foot should beadjusted according to the type of material beingsewn. The heavier the material, the heavier thepressure. The lighter the material, the lighter thepressure. The pressure should be only heavyenough to prevent the material from rising withthe needle and to enable the feeder mechanismto move the work along evenly. The pressurebecomes tighter as the regulating thumbscrew isturned clockwise, and looser as the thumbscrewis turned counterclockwise (fig. 9-45).

239.453Figure 9-44.—Bobbin thread tension.

239.454Figure 9-45.—Adjusting the presser foot pressure.

9-35

239.455Figure 9—46.-Stitch regulator.

Stitch Regulator and ReverseSewing and Tacking

For reverse sewing and tacking, proceed asfollows:

1. When the number 1 on dial A of figure 9-46is set uppermost on a vertical line, the feeder doesnot move the material.

2. When the dial (A) is turned counter-clockwise and lever (B) is raised as far as it willgo, the machine makes forward stitches, in-creasing in size as the dial knob is turned towardthe larger numbers.

3. For reverse sewing, lower the lever (B) asfar as it will go.

4. By moving the lever up and down duringsewing, you can easily make forward or reversestitches continuously and at will. You can makeuse of this feature for locking the thread at thestart or end of seams.

Straight and Zigzag Sewing

Be sure that stops S1 and S2 are set at theextreme ends of their slot. If not, use a screwdriverto loosen them about one turn, and then tightenthem in their extreme positions. Turning thezigzag regulating knob Z clockwise as far as it willgo causes the machine to sew with a straight stitch.Turning this knob counterclockwise produces a

zigzag stitch. The zigzag becomes wider the morethis knob is turned in a counterclockwise direc-tion. The widest zigzag stitch is sewn when knob Zcannot be turned any further. This occurs whenthe pointer at the underside of knob Z points atthe largest number on the dial and is stopped bystop S2.

When you want to control the width of thezigzag between certain minimum and maximumlimits between the numbers on the dial, use ascrewdriver to set stops S1 and S2 to the selectedwidths. Be sure to set stop S1 as far to the leftas possible when a straight stitch is desired.

NOTE: The zigzag regulating knob can bemoved into any desired position while themachine is operating. Do not turn thezigzag regulating knob when the machineis at rest and the needle is in the material.If you do you may bend or break theneedle. Turn the handwheel toward you toraise the needle out of the material beforeoperating the regulating knob.

Preparing the Machine for RopeStitching (Model 99R-3 only)

For rope stitching, the standard combinationof presser foot, feed dog, and (throat) needle plateis replaced with a special set of componentsdesigned specifically for this purpose. To do this,move slide plate (S of fig. 9-47) as far to the left

239.456Figure 9-47.—Rope stitching.

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as it will go. Using a screwdriver, remove the twoscrews holding the needle plate (N) to the bed ofthe machine. Remove presser foot (P) from thepresser bar and lift the needle plate off the bed.Now the feed dog becomes exposed. Loosen thetwo screws that attach the feed dog to its carrier,and remove the feed dog.

Proceeding in reverse order, first installthe special rope-sewing feed dog on the feeddog carrier, making certain that the twoscrews are tightened well. Next, put in placethe special (throat) needle plate, and thenthe special presser foot, tightening all theirscrews securely, and close the slide plate.

Adjust the stitch length and the widthof zigzag to suit the rope to be sewn.

Setting the Needle Barat the Correct Height

Before adjusting the height of the needle bar,make sure that the needle is pushed up into theneedle bar as far as it will go. Now, remove thefaceplate from the machine. Set the zigzag controlknob for straight sewing and turn the handwheeltoward you until the needle reaches the lowestpoint of its downward stroke. See that the needleenters the needle slot in the throat (needle) plateat the very center. When the needle is centered,proceed in the following manner:

Remove the slide plate, needle (throat)plate and feed dog. Continue turning the hand-wheel toward you until the needle bar hasrisen approximately 3/32 inch above its lowestposition. The point of the sewing hook shouldnow be at the center of the needle at adistance approximately 3/32 inch above theeye.

If adjustment should be required, loosen thesetscrew (B of fig. 9-48) in the needle barconnecting stud to raise or lower the needle baras may be necessary. Be sure to tighten thesetscrew after making this adjustment.

Centering the Needle in theThroat (Needle) Plate

If the needle needs centering within theneedle slot in the needle (throat) plate, set

239.457Figure 9-48.-Setting needle bar.

the machine for straight sewing and turn thehandwheel toward you until the needle barreaches the lowest point of its downwardstroke. Loosen setscrew (C of fig. 9-48)and turn eccentric stud (A of fig. 9-48) untilthe needle is centered correctly. Retightensetscrew (C).

Set the zigzag knob to the widest stitchposition and turn the handwheel toward you.Observe the passage of the needle through theneedle (throat) plate. It should pass at about anequal distance from either end of the needle slotwhen making the left and right zigzag stitch. Ifnecessary, readjust the eccentric stud (A of fig.9-48) as described before.

Timing the Sewing Hook

Remove the presser foot, slide plate, throat(needle) plate and bobbin case. Also remove thefeed dog. With anew needle in the machine, turnthe handwheel toward you until the needle barreaches its lowest point. Continue turning andallow the needle bar to rise about 3/32 inch whileon its upward stroke. With needle bar in this

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239.458Figure 9-49.—Timing sewing hook.

position, the point of the sewing hook should beat the center of the needle (fig. 9-49).

If the sewing hook is not timed correctly,loosen the three setscrews in its hub. Turn thehook on its shaft to align the point with the centerof the needle, as shown in figure 9-50. Tightenthe three setscrews.

To Remove and Replacethe Sewing Hook

Remove the needle, slide plate, and bobbincase. Take out screw (D of fig. 9-50) and removehook retainer (E of fig. 9-50). Loosen the threesetscrews in the hub. Turn the handwheel untilthe thread guard (widest part) of the hook is at

239.459Figure 9-50.—Sewing hook.

239.460Figure 9-51.—Removing sewing hook.

the bottom, then remove the sewing hook fromits shaft (fig. 9-5 1).

When installing a new sewing hook, have thethread guard at the bottom. Now turn the bobbincase holder until the notch (F) is at the top.Replace the hook retainer (E) watching that theprojection (G) near its end (fig. 9-50) enters notch(F) in the bobbin case holder. Fasten the hookretainer to the underside of the bed by means ofits screw. Replace the needle and time the sewinghook as described in the preceding paragraph.Reinstall the bobbin case, throat plate, and slideplate.

Timing the Feeding Mechanism

The feeding mechanism is timed at the factoryfor average stitching performance. Normal timingis such that the feed dog teeth, rising from theirlowest position, should be just flush with thesurface of the throat (needle) plate after the needlepoint has traveled about 5/16 inch above the platewhile on its upstroke.

To adjust the feeding mechanism, remove thetop cover from the machine. Turn the handwheeltoward you until the two setscrews, which lockthe feed eccentric into the main shaft, come intoview (fig. 9-5 1). Loosen both setscrews; lightly tapthe feed eccentric toward you to advance the feedtiming. To retard the feed timing, tap the eccentricto rotate it toward the rear of the machine.

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NOTE: Rotate the eccentric no more thanabout 1/16 inch, then tighten its setscrewsand check for results.

Timing the Movement ofthe Needle Bar Frame

Set the zigzag knob for straight stitch. Turnthe handwheel and observe the travel of the needleinto and out of the needle slot in the throat(needle) plate. If the needle is not centered in theslot, make the adjustments that have beendescribed.

Now adjust the needle to produce the widestzigzag stitch. Turn the handwheel toward you andobserve vibration (sidewise movement) of theneedle bar. The needle bar, on its upwardmovement, should begin to vibrate when the pointof the needle is no less than about 3/32 inch abovethe throat plate, and should stop vibrating whenthe needle has reached approximately the sameposition on its downward movement. To adjustthe vibration of the needle bar on model 99R,loosen the setscrews (H of figure 9-51) in thevibrator cam and slightly turn this cam on itsshaft. Tighten the setscrews and check for results.

On model 99R-3, the vibration of the needlebar is produced by a plate cam located at R onfigure 9-51. Loosen its setscrews and slightly turnthe cam on its shaft, following the same procedureas outlined in the preceding paragraph. Be sureto retighten the setscrews.

To Raise or Lower the Feed Dog

When at its highest position, the feed dogshould usually rise above the throat (needle) platethe full depth of the teeth.

To adjust the position of the feed dog, loosenscrew (J of fig. 9-50) and raise or lower the feeddog; then tighten the screw. When raising orlowering the feed dog, be careful that its undersidedoes not drop so low that it strikes the hook.

239.461Figure 9-52.—Adjusting thread take-up spring.

Adjustment of the Thread Take-up Spring

The thread take-up spring (K of fig. 9-52)should be set so that when the eye of the needlereaches the material on the downward stroke, thespring has completed its action and rests againstthe top of the thread take-up spring regulator.

If the thread take-up spring is not correct,loosen setscrew (L of fig. 9-52) and turn thetension stud (M) to the left for reduced movementof the spring, or to the right for more movement.After the take-up spring is set correctly, tightensetscrew (L).

Regulation of the tension of the thread take-up spring (K) is done by turning the tension stud(M) to the right to increase tension or to the leftto decrease it. Tension of the spring should justbe enough to take up the slack of the needle threaduntil the eye of the needle reaches the materialon its downward movement.

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CHAPTER 10

FABRICATION AND MANUFACTURE

Learning Objective: Upon completion of this chapter, you will be able toidentify and understand the tools, equipment, and procedures used to cut,layout, and fabricate specified projects.

As an Aircrew Survival Equipmentman, youneed to know what materials are best suited forthe job at hand if you are to be considered amaster craftsman of your trade. Therefore, to laythe groundwork to aid you in becoming a skilledPR, this chapter discusses the textile materials,tapes, webbing, thread, cards, knots, and seamsyou will use.

Many of the repairs you will be required tomake can be accomplished by replacing missingor worn hardware. There are occasions whenminor repairs require hand sewing becausemachine sewing is impractical or impossible. Forinstance, it might be advisable to make minorrepairs to aircraft upholstery by hand sewing therepair in the aircraft rather than by bringing theitem to the shop. On the other hand, most sewingis done by a sewing machine. A seam is usuallyconstructed faster, and is more durable, when asewing machine is used. The use of a sewingmachine gives the seam a better appearance. Todo your job right, you must know the types ofhandmade and machine-made seams and how tomake them.

TEXTILE MATERIALS,TERMS, AND MEANINGS

When a PR talks about warp, he doesn’t meansomething’s out of shape; and when he talks aboutfilling, he isn’t referring to teeth. He’s using termstextile manufacturers use, terms that are standardthroughout the textile industry. The Navy usesthese standardized textile terms to identify andclassify materials on Navy stock lists. AircrewSurvival Equipment Changes and Bulletins alsocontain some of these terms. To comply with theserepair instructions, you must first understand theterms used in them.

FIBER AND FILAMENT

Fiber is the basic unit used in the fabricationof textile yarns and fabrics. Vegetable, animal,and mineral fibers are natural fibers; nylon,dacron, and rayon are synthetic fibers. A filamentis an individual strand of material, and can be anylength. Filament is also another word for fiber,usually used when indicating or referring tosynthetic fibers. A fiber, or filament, is thesmallest unit in any type of cloth. An example isa silk filament, which may vary in length from300 to 1,000 yards. Synthetic filaments may beseveral miles long.

S t a p l e

The staple is the smallest unit of a naturallyoccurring fiber, or a synthetic filament cut in shortlengths to be combined with other fibers in themanufacture of a variety of materials. When usedin reference to the naturally occurring fibers, itdenotes quality or fineness, such as “long staple”cotton.

Yam

Yarns are continuous strands of textile fibersor filaments, in a form suitable for manufacturingtextile materials. The strength of the yarn isinfluenced by fiber strength, size, and length; sizeof the yarn; and tightness of twist. The strengthof textile fabrics is determined by yarn strengthand weight. You may form yarn by any of thefollowing processes: a number of fibers twistedtogether, a number of filaments laid togetherwithout twisting, or a number of filaments twistedtogether. Yarns formed by twisting a number offilaments together are referred to as multifilament(many filament) yarns. Ply yarn is two or moresingle yarns twisted together.

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239.367AFigure 10-1.—Textile terms.

Selvage and Raw Edges

The selvage edges of material, as shown infigure 10-1, are the edges of cloth, tape, orwebbing that are woven to prevent raveling. Whenthe material is cut, the resulting edge at the cutis referred to as a raw edge.

Warp

There are threads that run lengthwise of thecloth parallel to the selvage edge. If there is adifference in the strength of the warp and fillingthreads, the warp threads are usually stronger,because they form the framework for the materialand support most of the strain during the weavingprocess. Figure 10-1 shows both warp and fillingthreads.

Filling

Filling is also referred to as a woof, weft, orpick. It is the threads that run crosswise to thecloth as it comes from the loom. This term is notto be confused with filling in the sense of sizing,which means the addition of substances that givebody or decrease porosity of the material. Warpand filling threads must be determined in patternlayout because patterns (unless otherwise stated)are always cut with the warp and filling.

Weave

The weave is an interlacing of two sets ofthreads (warp and filling) to form a specific

pattern. The manner in which the material iswoven or constructed affects many of the clothproperties, such as tensile strength, airpermeability, and elongation.

Bias

A bias is a diagonal line of a cut, a fold, ora seam across a piece of textile material at an angleof 45 degrees to the direction of the filling threadsin the material. Bias construction is used to savematerial, prevent tearing between sections, andprovide elasticity where it is a requirement for asatisfactory performance of the article. The biasdirection of the fabric has a greater stretchingquality than the straight direction. A bias cut isshown in figure 10-1.

Tensile Strength

The force required to break a material is calledtensile strength. The tensile strength of a fabricis stated in pound-per-inch width for warp andfilling. The tensile strength of webbings and tapesis stated for the full width.

Cloth Weight

The cloth weight is the weight of a cloth, orfabric, in ounces per square yard. All fabrics havea designated cloth weight. For instance, a squareyard of cotton duck may weigh 8 ounces;therefore, it is called 8-ounce duck.

CONSTRUCTION FEATURESAND USES OF VARIOUS TEXTILEMATERIALS

If a cigar ash burns a hole in your tweedjacket, you will not patch it with a piece of velvetmaterial. If a life raft needs repair, you will notuse tweed fabric to repair it. Or, if an NES 12canopy needs repair, you won’t use 7.25-ouncenylon duck. If a repair is to make an item usable,

must use like material.In the not too distant past we were limited to

natural fibers as a source for our fabrics andassociated materials; but today, with the adventof synthetic fibers, we can enjoy theirimprovements in some respects over the naturalfiber. Currently the natural and synthetic fibershave the ir respect ive advantages anddisadvantages. Because you cannot use syntheticor natural fiber materials exclusively, you mustdecide which one best serves your purpose. There

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239.367BFigure 10-2.—Basic weaves.

are many, many different types of fabrics, orcloth. When we say cloth, we mean any textilematerial over 12 inches wide from selvage toselvage.

The construction of cloth is determined bymany factors, such as tightness of yarn twist,number of threads per inch, porosity of the yarns,and the type of weave used in its formation. Theweave is one of the most important factors. Thetwo basic weaves are plain and twill (as shownin figure 10-2). The plain weave is the simplestmethod of weaving and gives the smoothestsurface of the fabric. It consists of the fillingthreads passing over one warp thread and underthe next warp thread. The twill weave is a morecomplicated weave in which the filling threadspass over and under more than one warp thread,thereby producing a surface on the fabric that isgenerally recognized as a diagonal pattern.

Cotton

Cotton is a natural plant fiber, usually white.The fibers or “staples” are between 3/8 and 2inches in length. Chemically, it is almost purecellulose. Cotton fabrics, webbing, and tapesabsorb water readily unless treated. They drymore slowly than the synthetic fabrics and aremore susceptible to mildew and fungus growth.One should never ignore the presence of mildewbecause it seriously affects the tensile strength ofcotton and other fabrics. Heat is less damagingto cotton than to the synthetics. Insect damage

should, however, always be considered becausecotton is a food for certain cellulose-eating insects,and cotton makes good nesting or cocoon-spinning material for rodents and insects.

Nylon

This is a synthetic fiber of extreme toughnessand elasticity. It absorbs very little water, driesquickly, is mildewproof, and is not affected bymost ordinary oils, greases, or cleaning fluids. Itis also mothproof. It is sensitive to some chemicalfumes, excessive heat, and direct rays of sunlight.Nylon melts and drips when it is subjected to fire.This characteristic requires that precautions betaken when nylon is worn where there is a riskof fire. Melted nylon on the skin can cause themost serious of burns.

NOMEX Fabric

NOMEX is the trade name for a fabric thatis used in the construction of flight suits. NOMEXfabric is a high-temperature resistant andinherently flame-retardant synthetic fabric. Thisfabric has no melt point or drip characteristicswhen it is subjected to fire. NOMEX material islight in weight, does not support combustion, butbegins to char at 700° to 800 °F. The fabric,similar to nylon, is abrasion resistant, and is alsononabsorbent.

Duck

This is a comparatively firm, coarse, plain-weave, cotton fabric with weight per square yardfrom 6 to 50 ounces. Duck is frequently calledcanvas. It is primarily used in the construction ofprotective covers because of its durability andwearing characteristics.

Rubber and rubberized fabrics are usedin the manufacture of exposure suits andflotation equipment because they are water-tight. Rubberized materials are susceptibleto deterioration if subjected to heat andmildew. Foam rubber is thick and resilient andis used for padding in upholstery and aircraftcrash pads.

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Leather

Cowhide or horsehide may be used forreinforcing patches where heavy wear occurs. Itis used for reinforcing patches for grommets andchafing strips on seat belts. Artificial leather hasreplaced the natural product, and is used to a largeextent for seat pad, crash pad, and upholsterycovering.

Vinyl

Vinyl is a plastic material and is used in manyinstances in the fabric shop. Vinyl is available invarious thicknesses, depending on its intended use.It may be used for seat covers or ventilatingclothing. The type used for ventilating clothingconsists of two layers of flexible vinyl film. Vinylis vaportight and has a smooth surface. Soap andwater can be used to clean it. Do not use ammoniadetergents for cleaning because this bleaches thevinyl.

WEBBINGS AND TAPES

You already know that cloth is fabric widerthan 12 inches. Any fabric less than 12 inches,from selvage to selvage edge, is called webbingor tape. The dividing line between webbing andtape is determined by the respective weight.

Webbings

The heavier of the two is webbing. Webbingweighs over 15 ounces per square yard and is lessthan 12 inches wide. As you would expect,webbings are used for the toughest holding andreinforcing jobs. Slings, harnesses, safety belts,reinforcing and securing straps are made of nylon,with a wide variety of tensile strength. Thepersonnel parachute harness has a tensile strengthrange of 6,000 to 8,700 pounds. Some nylonwebbings are of tubular construction, whichmakes them very strong. Tubular webbings are1/2 to 1 inch wide, with tensile strengths rangingfrom 1,000 to 4,000 pounds.

Tapes

In addition to webbings, there are thelightweight tapes of a twill weave construction.You can use tapes for reinforcement on manytypes of fabric covers. Tapes can weigh up to 15ounces per square yard. Cloth tapes are wovenin the same manner as fabric. Some are bias,

which, because of the bias cut or construction,aid the binding of curved edges where stretchingqualities are desired. These bias tapes aresometimes referred to as binding tapes.

Velcro tape is commonly used in manyshops as a fastening or closing device. Velcrotape consists of two parts-the hook and thepile or loop tape. The hook tape is made of nylon,which consists of a series of small hooks. Thenylon pile or loop tape has many small loops.When the two parts of the tape are joined, thehooks engage with the loops holding the two tapestogether.

DIFFERENCE BETWEENTHREADS AND CORDS

The difference between threads and cords isdiscussed in the following text.

Threads

Filaments (nylon) or staples (cotton) aretwisted together to form yarns, and two or moreyarns are twisted together to forma thread or plyyarns, as the yarn by itself is too small forpractical use. The strength of a thread dependsupon the size and number of yarns used to makeup the thread. The thread numbers on spoolsindicate the size of the yarn and the number ofyarns that are piled (or twisted) together to givethe necessary strength to the thread. For example,a 16-4 thread indicates that the thread was madefrom a single yarn, size 16, and that four of thesesingle yarns were twisted together to make athread. The finer the yarn used, the higher its sizenumber. Silk and nylon thread sizes, however, areindicated by letters, such as A, B, etc.; A is finerthan B; the farther down the alphabet, the coarserthe thread.

Thread is twisted to the left or twisted to theright, depending on its use. Left-twist thread isalways used in the sewing machine because theaction of the stitch-forming mechanism tends toravel or break right-twist thread. Left- or right-twist thread may be used for hand sewing. Theterms that designate left-twist threads aremachine, machine twist, left twist, and Z twist.A cord or thread has left (or Z) twist if, when heldin a vertical position, the twist of the yarn followsthe slope of the central portion of the letter Z;and right (or S) twist, if it follows the slope of

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the central

239.368Figure 10-3.—Thread twist.

portion of the letter S, as shown infigure 10-3.

Cords

Unbraided and braided cords are covered inthe following paragraphs.

UNBRAIDED CORDS.- Unbraided cord istwisted together in the same manner as thread,as shown in figure 10-3. The difference betweenthreads and cords is that cords are stronger andlarger in diameter than threads.

Nylon cords play an important part in therepairing of life support items. To identify nyloncord, you must remember that the larger thenumber, the larger and stronger the cord.

BRAIDED CORDS.- You know that a braidis three or more strands of material entwinedtogether. Cords also come braided, and in twotypes: a solid woven cord or a cord with a hollowchannel center, as shown in figure 10-4. Solidwoven cords are flat. Hollow channel cordssometimes contain several straight, individual

Figure 10-4.—Braided cords..

threads, known as a core. This core increases thestrength of the cord and keeps the outer braidedcover round. Parachute suspension lines are madefrom this type of cord.

STORAGE OF TEXTILE MATERIALS

It is necessary to know the general principlesof care and storage of materials because theydiffer greatly in their resistance to damage suchas moisture, heat, mildew, fungus, insects, androdents. There are certain insects, however, thatwill eat almost anything; mice build nests inalmost any kind of stored fabric material; andthere are hundreds of fungus growths that thriveunder moist tropical atmospheric conditions.Conditions in various parts of the world varywidely in regard to humidity, heat, or cold, andthe presence of insects. Such conditions must betaken into account when you are storing andprotecting materials. The following ideal storageconditions should be attained as nearly aspossible: a dry room with temperature of 70°F,absence of direct sunlight, a storage roomconstruction that affords protection againstinsects and mice, wooden shelves for storage, andair conditioning or some other method ofhumidity control.

Now let’s consider some of the characteristicsof materials that you should know if you are tobe responsible for keeping them in storage. Nylonabsorbs very little water, dries quickly, is

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mildewproof, and is not affected by most ordinaryoils, greases, or cleaning fluids. It is mothproof,and, because it is not an animal fiber like woolor silk, does not offer food to hungry insects.However, if insect larvae develop from eggs laidinside the folds of stored fabrics, they may eattheir way out. Soiled or greasy spots in a fabricattract insects.

Soot and certain chemical fumes are highlyinjurious to nylon, and direct heat and exposureto the sun’s rays seriously weaken it.

Rayon has many of the characteristics ofnylon. It is more easily damaged by direct heator the sun’s rays and is more combustible thannylon. Rayon fabrics “take a set” (form a crease)more easily than other fabrics, and if left storedin folds for too long, they will form permanentcreases.

Cotton fabrics, webbings, and tapes, unlesstreated, absorb water readily. They dry moreslowly than synthetic fabrics and are moresusceptible to mildew and fungus growth. Mildewshould never be ignored because it seriouslyweakens cotton or other fabrics. Heat is lessdamaging to cotton than to the synthetics. Bugsor their larvae will eat cotton or use it to makecocoons or nests.

In all cases, fire is a constant threat to fabrics.Smoking should not be permitted where fabricsare handled or stored. The rayons are almostexplosive when set afire. Nylon, although harderto ignite, will bum, but does not explode in theprocess. You should be careful to learn the storageproblems peculiar to any specific locality orclimatic conditions to ensure safe storage of thesematerials.

The construction and characteristics of variousfabric products has been explained to give yousome basis for the intelligent use and storage ofthese materials. Besides textile materials, you arerequired to use dopes, cements, and solvents inthe daily performance of your duties as afabrication and parachute specialist.

ENGINEERING REQUIREMENTSFOR FABRICS

If a parachute is to serve its purpose, it mustbe reliable. To be reliable, parachutes must meetcertain engineering requirements.

At this point you may be wondering whyyou should be concerned with engineering re-quirements. After all, you are not designingparachutes. You service parachutes. Here is wherethe difference shows up between just a parachute

packer and a good parachute rigger. Almostanyone can learn to pack a parachute. But a goodparachute rigger needs to understand the’ ‘why”that determines maintenance procedures. Whenyou have learned the engineering and aerodynamicprinciples that affect parachute reliability, you willknow why it is so important to be a conscientiousand precise worker. And, you will see to it thatthose who work for you do their job exactly right.First, the engineering requirements for parachutesare listed and explained below. Then you will learnwhy the textile most often used in parachuteconstruction is nylon.

Air Permeability

The term air permeability refers to themeasured volume of air in cubic feet that flowsthrough 1 square foot of cloth in 1 minute at agiven pressure. If a material gets wet and shrinks,it has less air permeability y, because the weavedraws together and less air gets through. This isthe reason for that very important rule: DONOT, FOR ANY REASON, PACK A WETPARACHUTE. Also, a wet parachute assemblycan freeze at high altitudes. Air permeability yaffects the reliability, opening time, opening force,canopy drag, and stability of the parachuteassembly.

The proper ratio of air entering a parachutecanopy to air passing over the canopy gives aparachute good performance. The greater theairflow through a canopy, the slower the openingtime. This is why canopy designs differ. A quickopening time is required for personnel parachutes,but a slower opening time is desired fordeceleration and cargo parachutes. The brakingforce in deceleration and cargo parachutes is builtup over a longer period of time, which enablesthe parachute assembly to withstand anddecelerate greater loads.

Strength

The term strength refers to a fabric’s abilityto resist strain or rupture by external forces.Strength is expressed as tensile strength (a termyou already know) and is measured in pounds persquare inch. The strength of the fabric determinesthe strength of the parachute. Remember the oldsaying about the chain being only as strong as itsweakest link. Strength is a very importantrequirement for a safe, reliable parachute. Referto table 10-1 for tensile strengths of fabrics,webbings and tapes.

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Table 10-1.—Tensile Strengths

Elongation

The term e longat ion d e s c r i b e sdeformation, lengthening, or stretching caused bya tensile force. It’s what you do when you stretcha rubber band. The ability to elongate gives stretchto a fabric. Elongation is expressed as thepercentage of stretch over the original length. Forinstance, if a tape has 10 percent elongation, a10-inchbreaks.percent

piece will stretch to 11 inches before itParachute specifications call for 20-25elongation.

Elasticity (or Elastic Recovery)

The term elasticity describes the ability of afabric to elongate (or stretch) when tension isapplied, and to recover its original shape whenthe tension is released. If you stretch a rubberband and then let it go, it comes back to itsoriginal size. To test the elesticity of a material,stretch it 4 percent and then measure to see howclosely it returns to its original length. A fabricthat returns to within 75 to 95 percent of itsoriginal length after being stretched is said to

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have satisfactory elasticity. A parachute madefrom fabric with good elasticity is stronger andgives less opening shock.

Weight

Lightweight fabric is an absolute necessity forall parachute canopies. A canopy of lightweightmaterial opens faster. Can you imagine a pilotwalking around wearing anything as heavy as acanvas beach umbrella? Lightweight cargo anddeceleration parachutes enable the aircraft tocarry more weight in cargo and fuel.

Resistance to Abrasion

This refers to a fabric’s ability to withstandwear and rubbing. In its lifetime, a parachute issubjected to a great deal of abrasion. When youpack a parachute, you pull the canopy down thetable. A deceleration parachute slides along therunway. For this reason, deceleration parachuteriser webbings and personnel parachute harnessesand risers are treated with Merlon (brand name)to make them more resistant to abrasion damage.

Resistance to Mildew and Insects

Moths and other insects love to feast onfabrics; mildew and other fungi thrive on themin warm, damp climates. Parachutes damaged bymildew or insects would be unsuitable for Navyuse. Therefore, it is necessary that parachutefabric be as resistant as possible to this type ofdamage.

Moisture Regain

The term moisture regain refers to thepercentage of moisture that a bone-dry fiberabsorbs from the air under standard conditionsof temperature and humidity (65 percent relativehumidity and 70 “F). Less than 5 percent moistureregain means that the fibers build up static electriccharges when rubbed. If static electricity buildsup, the parachute assembly is more difficult toservice. Static electricity also adversely affects theopening time of a parachute assembly.

The ability to take on dye (color) is anotherimportant consideration when selecting parachutefabrics. The percentage of moisture regainpossible in a fabric determines whether it can besuccessfully dyed. Dying gives the fabric color,which is important for a parachute canopy.Rescue teams can easily spot multicolored

canopies from the air. Pickup crews can quicklyidentify colored deceleration canopies onrunways. Also, yellow dye in a canopy makes itmore resistant to ultraviolet damage fromsunlight, which relates to the next engineeringrequirement on this list.

Resistance to Sunlight

Ultraviolet light, which is found in sunlight,reduces the strength of fabrics. Ultraviolet raysgive you a painful sunburn when you’re out onthe beach too long. All parachutes are exposedto some sunlight. Military specifications forparachute materials state fabrics should not losemore than 25 percent of their original strengthafter 50 hours exposure to sunlight. Investigationsinto causes of deceleration parachute failures haveshown strength loss of more than 50 percent after50 hours of exposure to sunlight.

Resistance to Heat

In addition to sunlight, heat and friction arenatural enemies of a parachute. In case of fire onan aircraft, personnel and deceleration parachutesmay be exposed to great amounts of heat. Frictionand heat are generated when the decelerationparachute comes in contact with the runway. Line-overs cause friction and burn holes in parachutecanopies. Line-overs happen when an improperlystowed suspension line is drawn over the canopyduring deployment.

Resistance to Chemicals

Because parachute assemblies are exposed tovarious chemicals, it is important to know whichchemicals are harmful and which are not. Mostdamaging are mineral-type acids, such as the typeused in batteries.

You have studied a long list of engineeringrequirements that are important to know whenyou service parachutes. You already know thatnylon is the most widely used fabric in theparachute shop. In the following text, we examinethe good and bad characteristics of nylon inparachute construction.

There is no fabric known to man thatmeasures up perfectly to all the engineeringrequirements for parachute construction. Butnylon comes closer, by far, than any other fabric.Nylon, when properly handled by the parachute

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rigger, has more good than poor qualities.First, we will review the good characteristics ofnylon:

1. Strength. Nylon is one of the strongestsynthetics made.

2. Elongation. Nylon stretches from 18 to 40percent, which is well above military specificationsof 20 to 25 percent.

3. Elasticity. Nylon returns to 100 percent ofits original length.

4. Weight. Nylon fibers are very strong fortheir weight; therefore, the fabrics manufacturedof nylon fibers are lightweight fabrics.

5. Resistance to abrasion. Nylon doesn’t haveenough resistance to last forever under all therugged use parachutes get, but it is better thanany other material tested for parachute use.

6. Resistance to mildew and insects. Nylonhas no food value. This makes it unappetizing tomoths and other insects. It cannot support thegrowth of mildew. This isn’t true, however, whena cup of coffee is accidentally spilled on aparachute assembly, or other edible foreign mattercomes in contact with it. What we really meanis clean nylon has no food value.

We warned you that nylon is not the perfectfabric. Where possible, improvements have beenmade in manufacturing nylon. The limitations youmust keep in mind when handling nylon are asfollows:

1. Moisture regain. Remember, we said thatif the percentage of moisture a fiber absorbs fromthe air is less than 5 percent, the fiber is difficultto dye and builds up static electricity when rubbed.The moisture regain of nylon is only 4.2 percent,so you can expect static electricity to develop asyou service the assembly.

2. Resistance to sunlight. We mentionedearlier that yellow dye improves resistance toultraviolet light damage. That is why yellow dyeis added to deceleration canopy material. Inaddition, a chemical known as Chemstrand “R”has been developed, which, when added to nylonfiber as the yarns are manufactured, makes nylonmore resistant to ultraviolet light.

3. Heat resistance. Nylon has a relatively lowmelting point, 482 °F, which makes it verysusceptible to damage from heat. This is why itis so important that suspension lines be stowedproperly. In the rapid deployment sequence, linescrossing each other will break from the frictionheat generated.

In short, there are several natural enemies tobe aware of when you handle parachute textilesof any type. These are the hazards of sunlight,abrasion, heat, chemicals, insects, and fungi onparachute components.

Keep in mind the natural enemies of textilesyou have learned. Then it is easy to see whichelements are to be avoided when you storeparachute fabrics.

SPECIAL HAND TOOLS

When working in the fabric shop, you will findthat you have a need for tools that are notcommonly stocked in the average tool room.Therefore, we must discuss some of the specifictools used in the fabric shop. The tools used forfabric and rubber maintenance are not highlycomplicated, but they are designed for a specificpurpose. In your hands these tools can helpproduce a finished product of which you can beproud.

SHEARS

A scissor-type tool that you often use forfabric work is known as shears, as shown in figure10-5. A pair of shears consists of two cutting edgesso hinged that, when closed, the cutting edgescross each other in close contact. This shearingaction is used for cutting fabrics. The large loopin the handle is for two or three fingers and thesmall loop is for the thumb. The blades are notstraight, but are slightly curved toward each otherso that, inclosing, the two cutting edges are heldfirmly together by the spring action of the blades.

Always keep the shears sharp. If the shearsare not sharp enough to effectively cut thematerial, they must be sharpened. A more

239.370Figure 10-5.—Shears.

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effective job can be done by disassembling theshears and sharpening one shear at a time. Thebottom shear has a more blunt angle than theupper, so exercise care in the cutback or angle ofsharpening. Also in sharpening, start at the pointor toe of the shear and move toward the heel ofthe shear. This drives the heat, generated ingrinding, to the heel of the shear where there ismore metal to radiate the heat. To grind towardthe toe or point drives the heat to the lesser metal,and it can result in burning the metal and drawingthe temper out. After grinding the shear,reassemble it loosely at first so that, on the firstclosing, the wire edge resulting from the grindingis removed.

Another type of shears you will use is knownas pinking shears. This tool is used for cutting aseries of Vs along fabric edges to prevent fraying.If pinking shears become dull, they should bereturned to the manufacturer for sharpening.

Remember, always keep the shears sharp.Don’t drop your shears, as this springs the bladesand reduces their cutting ability. DON’T use themto puncture metal objects or to pry things open.DON’T use shears as a knife to remove stitching;you may injure yourself or damage the stitchesyou are cutting. (For this job, use an upholsterer’sknife or a stitch cutting tool.) When shears arebeyond shop maintenance capabilities, returnthem to supply for a replacement.

FOOT-OPERATED GROMMET PRESS

With the foot-operated grommet press, asshown in figure 10-6, you can install grommetsby mass production. The press itself stores the twoparts of the grommet, leaving your hands free toposition material while your foot applies theneeded pressure. The important parts of this pressare the chuck and die. For each type and size ofgrommet, there is a corresponding chuck and die.The chuck is the upper tool; the die is the lowertool. Use the adjustment screw, located either atthe top or bottom of the foot-operated press, toprevent pressure damage to the chuck and die.When set correctly, this adjustment screw will setthe clearance of the chuck and die to 1/32 inch,about the thickness of bond typing paper, whichis adequate for most grommets. Some foot-operated presses have been in service for as manyas 25 years and still require only the replacementof the chuck and die. The foot press may also beused in the shop to install glove fasteners.However, if a portable glove fastener installationtool is needed, you can use the hand press.

239.371Figure 10-6.-Foot-operated press.

HAND PRESS

The Durable Fastener hand press, as shownin figure 10-7, mates the two female portions ofthe fastener (socket and button) and the twofemale portions (stud and eyelet). You will usethis often as you replace Durable Fasteners onsoundproofing, cushions, or other related itemswhere a portable installations tool is required.

KNIVES

A knife, because of its familiarity, can be oneof the most abused tools. At its best, a knife has

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239.372Figure 10-7.-Hand press.

a well-sharpened blade and a secure handle.DON’T use any knife as a screwdriver, a punch,or a pry to open can lids. Always cut away fromyou, and keep your hands out of the way of theblade.

To sharpen a knife, use an oilstone and applythe same basic principle as that used forsharpening shears. Do NOT sharpen a knife bladeon a grinding wheel because the metal is too thin.Too much heat is generated for the thickness ofthe metal. To sharpen a knife, clean the oilstoneof all gum and dirt accumulation. Put two or threedrops of medium-light oil on the stone. Lay theknife on the stone with the back of the knifeslightly raised. Draw the knife toward you witha diagonal stroke from heal to toe with the cuttingedge advancing. Turn the knife over and movethe blade away from you, cutting edge advancing,moving from heel to toe. Repeat these stepsseveral times. The edge is sharp if you feel adecided drag when passing it lightly over a wetthumbnail. No drag indicates the edge is notsharp.

MEASURING DEVICES

The ruler, tape measure, and carpenter’ssquare, as shown in figure 10-8, are used oftenduring the repair of fabric and rubber articles.These may become special tools by adding aspecial mark to show a commonly used scale ormeasurement. To comply with technical directivespecifications, be sure to exactly measure items

239.373Figure 10-8.-Measuring devices.

such as the patch overlaps, length of lines on liferafts, and every other job you do that requiresspecial measurements.

The 12-inch, plain steel rule is used for layingout and measuring small work. One side of therule, shown in view A of figure 10-8, has one edgegraduated in sixteenths of an inch and the otheredge graduated in eighths of an inch. This isindicated on the rule by the numbers 16 and 8,which are stamped into the metal. The opposite

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side of the same rule may have one edge graduatedin sixty-fourths of an inch and the other edgegraduated in thirty-seconds of an inch, as shownin view B of figure 10-8.

STAR PUNCH

The carpenter’s square is a steel tool in theform of a right angle. One arm is 24 inches long,and the other is 18 inches long. It is used by thecarpenters to lay out the framework of buildingsand to square off wood materials. The fabricationand parachute worker uses it for layout work andmeasuring.

HARDWARE

The tape measure is a convenient tool. It isused to measure large objects, yet it is portableand can be carried in a pocket. The tape measureis flexible and allows you to measure curvedobjects. These measuring devices (ruler, tapemeasure, and carpenter’s square) are used toachieve accurate and professional results.

SAILMAKER’S PALM GROMMETS

The sailmaker’s palm has a small metal diskinsert set in rawhide and stitched into a leatherglove-type device. It is designed to be worn in thepalm of the hand, and it is used to aid in pushinga sail needle through the material being sewn ortacked (fig. 10-9).

AWL

The awl is another instrument used as an aidin sewing heavy material where pushing the sailor hand sewing needle through the materialbecomes difficult. It is a sharp-pointedinstrument, with a handle attached, and is usedfor punching holes in a heavy fabric or materialprior to inserting the needle. Never use a hotneedle or iron as a substitute for the awl.

Figure 10-9.—Sailmaker’s palm.

The star punch or leather punch is a veryuseful tool for punching holes through materialto be fastened with snap fasteners or speedy rivets.

Looking back through the first two sectionsof this chapter, you see that we have discussedtextile materials and tools. This section is alsoconcerned with a different type of material oftenused in the fabric shop. We call it hardware.Grommets, glove fasteners, and interlockingfasteners are pieces of hardware you use duringyour daily work. You must install pieces ofhardware to covers, bags, and clothing tostrengthen or to secure these items. Not only doyou have to be able to identify this hardware, youalso have to know how to install it properly.

You use grommets whenever it is necessary toreinforce holes for lacings in covers, bags, panels,and upholstery. There are two parts to a grommet:the grommet itself or collar and the washer. Thetwo types of grommets used are plain and spurgrommets, as shown in figure 10-10.

The plain grommet uses a plain washer,whereas the spur grommet uses a toothed washerthat bites into the material to form a grip. Thespur grommet, because of its strength, is usedwhere the pull will be particularly strong; or it maybe used in large covers. Leather is sometimes usedat corners to reinforce the area where grommetsare to be installed. Grommets are made ofaluminum, brass, or chrome-plated brass. Theyare available in several sizes (00, 1, 2, 3, 4, etc.);

239.304AFigure 10-10.—Grommets—p1ain and spur.

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the smaller the number, the smaller the size of thegrommet.

To install grommets, you must proceedthrough a series of operations. Locate andmark where a grommet installation is needed.Be sure you set the grommet far enough fromthe edge of material to prevent it from tearing.Select the correct punch by matching its size tothe size of the grommet collar, as shown in figure10-11.

After you have used the leather cuttingpunch to cut a hole in the fabric, youmust mate the parts of the grommet. Placethe grommet on the finished side of thematerial and the washer underneath. Deter-mine the correct size chuck and die. As-semble the grommet, washer, punch, anddie, as illustrated in figure 10-12. Now youare ready to flatten the collar. This opera-tion can be accomplished in a variety ofways, depending upon the availability oftools .

Grommet Press Installation

You may have a foot-operated grommet pressor a hand press, as illustrated in figures 10-6 and10-7. To use either type of press, you need anassortment of chucks and dies. Install the die inthe bottom of the press and the chuck in the topof the press. Set the foot press and check for aclearance of the thickness of heavy paper betweenthe chuck and die. This prevents damage bystriking the chuck and die together. By depressingthe foot pedal or handle, you securely flatten thegrommet.

239.374Figure 10.11.—Inside diameter measurements.

239.375Figure 10-12.—Grommet collar, cloth, and washer in

grommet set.

Grommet Set Installation

A grommet set, consisting of a punch anddie, is used to install grommets in material.Figure 10-12 illustrates a grommet set. Thegrommet set has to be the same size asthe grommet for a proper grommet installation.Use a rawhide mallet to strike the punch. Thisaction flattens the grommet. The grommet setinstallation is used because of its simplicity andportability.

GLOVE FASTENERS

The most common type of fastener used onclothing and other items made of fabric andrubber is the glove fastener. In many instances,the glove fastener has replaced the conventionalbutton. Glove fasteners are dependable and areused for their holding and firm gripping ability.Figure 10-13 shows the three different types ofglove fasteners most commonly used. The maindifference between the three fasteners is size. TheSegma Dot is the smallest; the Durable Dot is thelargest type of glove fastener. Each fastener ismade of four parts: button, socket, stud, and

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239.377Figure 10-13.—Glove fasteners.

eyelet, as illustrated in figure 10-13. The socketand button are matched to form the snap. Thestud and eyelet form the part to which the socketand button snap.

239.303AFigure 10-14.—Durable dot fastener installation.

Press Installation

Cut a hole the size of the collar of the buttonand insert the button in the material. Place thecorrect chuck and die into either a foot-or hand-operated press, as shown in figures 10-6 and 10-7.The die is the lower and the chuck is the uppertool, as shown in figure 10-14. Fit the socket tothe chuck, as shown in figure 10-14. Lay thebutton in the die and complete the attachment bydepressing the handle or foot pedal. Cut theproper size hole in the material to receive theeyelet. Place the correct chuck and die in the press.Insert the collar of the eyelets through the holefrom the back of the material. Fit the stud intothe chuck. Lay the eyelet on the die and completethe attachment.

Hand Installation

Cut a hole the proper size for the collar of theglove fastener button. Insert the button in thematerial and place the socket over the collar ofthe button. Make an indentation in a wooden

239.378Figure 10-15.—Flaring button collar.

block for holding the head of the button. Flarethe collar of the button slightly with a centerpunch, as shown in figure 10-15. Flatten the collarof the button with a solid drive pin punch.Assemble and install the stud and eyelet on theother pieces of material so the base of the eyeletis on the backside of the material. Flare andflatten the collar of the eyelet in a manner similarto the installation of the button and socket.

THREE-WAY LOCKING FASTENERS

There are times when you need to use a snapfastener that has extra security. When you musthave this type of fastener, you should use eitherthe three-way locking snap or the curtain fastener.

THREE-WAY LOCKING SNAPS

The three-way locking snap is stocked in onesize only—regular. It is used on fight clothing,

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CURTAIN FASTENER

Figure 10-16.—Three-way

parachute containers,

239.298locking snap-type fastener.

and back pads. (Seefigure 10-16). This fastener opens only whenlifted from the side, with the dot locatedon the top of the button. When installingthis snap fastener, you should ensure thatyou install the three-way locking snap inthe position that you want to be opened.This type of snap should never be usedwhere any quick-opening devices or quick-releasing action is required.

The curtain type fastener (lift-the-dot)is stocked in two sizes—large and small.(See figure 10-17). These fasteners have manyuses, especially for truck and boat covers.The small lift-the-dot is the same as thelarge one, and designed on a smaller scalefor use on lighter work where the bulkinessand weight of the large lift-the-dot are notdesired.

INTERLOCKING SLIDE FASTENERS

Tasks are accomplished more easily andquickly through the use of interlocking fasteners.For example, they save precious seconds foran aircrewman when he is donning his flightclothing or exposure suit. These fastenersalso provide the repairman with a means ofeasy access to items that require inspections.

The types of interlocking slide fasteners(zippers) used on flight clothing and otheritems of aviation equipment are shown in

239.299Figure 10-15.—Large curtain-type fastener (lift-the-dot).

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Figure 10-18.—Slide fasteners.

figure 10-18. Figure 10-19 shows the parts of an the slider, which, when moved, displaces teeth atinterlocking fastener.

Interlocking Slide FastenerConstruction

An interlocking slide fastener consists of twochains of teeth (hollow cones or scoops) facingeach other. When brought together at the properangle, each tooth fits within the scoop of the toothopposite it.

When closed, the interlocking slide fastenerteeth cannot be parted except through the use of

the proper angle for meshing and unmeshing. Thesmall clips (stops) at the top and bottom of theinterlocking slide fastener are designed to preventthe slider from running off the track. Separating-type slide fasteners do not have a bottom stop,but are equipped with a pin on one side andretainer arrangement on the other to allow the twoparts of the slide fastener to separate.

Interlocking SlideFastener Operation

Ordinary interlocking slide fasteners aredesigned for flat, smooth operation. Both handsare required for proper functioning. The chainsshould be stretched taut with one hand and the

Figure 10-19.—Slide fastener239.308

parts.

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slider worked (without force) with the other.When operating an interlocking slide fastener

installed in a garment of soft nappy material, orlined with wool or fur, do so with care to preventthe nap or wool from jamming the slider.

Very often grease or oil deposits lodge betweenthe tiny hollow parts of the teeth and accumulatedirt and lint. This causes stiff operation of theslider. A dirty or gummed chain should be cleanedwith an old toothbrush or a pipe cleaner saturatedwith Stoddard solvent or other similarly approvedcleaning solvent. After each cleaning, the chainshould be lubricated by applying one drop of oilor a small amount of graphite between yourthumb and forefinger and running the chain upand down between your fingers several times.

239.309Figure 10-20.-Slide fastener pull tabs.

A brief inspection will determine whether aslider (or pull tab) is the locking or nonlockingtype. Always be certain that the pull tab is liftedat right angles to the slider before attempting toremove the locking type. The relative positionsof the pull tabs are shown in figure 10-20.

Interlocking Slide Fastener Tools

In addition to common tools such asscrewdrivers, pliers, awls, knives, scissors, andneedles, a well-equipped slide fastener kit shouldbe included in the parachute loft equipment.

The interlocking slide fastener kit (zipperrepair kit) contains all the parts necessary to repairany size or type of interlocking slide fastener, plusthe following special tools: end cutters, or nippers,used for removing stops and teeth; stop-closingpliers, specially designed to span over the sliderand clamp the stops in position; and pull-up pliers,

designed to close the slider without a pull tab.Another handy tool in slide fastener repair is anawl with a bent tip. This tool maybe used to closethe chain by hand.

Interlocking Slide Fastener Repair

A torn or ripped interlocking slide fastenerbead cannot be repaired, but should be replacedwith a complete new interlocking slide fastener.If the bead is damaged near the top or bottomof the interlocking slide fastener, and the damagedends can be cut off to shorten the interlockingslide fastener without hampering the usefulnessof the garment, an effective repair can be made.

Loose or missing teeth and stops can causetrouble. If teeth or stops are not tightened, theywill eventually be lost and tear the bead. Inrepairing such damage, see that the loose stop isin position (almost touching teeth), and then settightly with stop-closing pliers. Set any loose teethparallel with the other teeth in the chain, and thenapply pressure with the stop-closing pliers. Set anyloose teeth parallel with the other teeth in thechain and apply pressure with the stop-closingpliers. If a replacement stop is not available inthe repair kit, a soft wire or heavy thread maybe used as a temporary stop.

A missing tooth should be repaired byreplacing the entire interlocking slide fastener.However, in the event that there are no sparefasteners available, a missing tooth may bereplaced. This is done by carefully removing thestop from the top of the chain, taking off the toptooth, replacing the stop, and setting the toothin place. (You should be careful not to damagethe bead of the chain when resetting the tooth.)

You may run into trouble in moving the slideron the chain. This is caused by the jaws of theslider being too tight, or a dirty chain maybe thetrouble. To loosen the slider, insert a screwdriverbetween the jaws, and very gently pry them apartuntil they operate freely.

Should the slider become jammed with fur,wool, or other material, carefully remove suchmatter with a pin or needle while gently pullingthe slider until it is released. If it is so badlyjammed that it resists all efforts, remove the sliderby carefully bending the jaws apart and returningthe jaws to their original position. Then replacethe slider on the chain (described later).

Most pull tabs have two small projectionsfitting into slots on each side of the slider. Toremove the pull tab, use two pairs of pliers, oneon each side, and twist in opposite directions. In

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239.310Figure 10-21.—Removing the slider.

replacing pull tabs, this procedure is reversed. Pulltabs furnished as replacements need only to besqueezed onto the slider.

To repair a damaged slider, you must firstremove it. The proper procedure for removing andreplacing a slider on the chain following repairsis explained in the following paragraphs.

To remove the slider from the regular typeinterlocking slide fastener (nonseparating),carefully rip the stitches from the BOTTOM ofthe interlocking slide fastener to expose the endsof the tape. Then remove the bottom stop, andslip the slider off the bottom of the chain andentirely off the beads and tape, as shown in figure10-21.

To replace the slider on a regular typeinterlocking slide fastener, thread the two bottombeads into the wide end of the slider. Hold thetape so that the bottom teeth are correctlymatched; then draw the slider upward until theteeth mesh for several inches. Without allowingthe teeth to separate, clamp the bottom stop closeto the teeth and over both beads. Replace the tapeends and ripped stitches by hand or by machine.

To remove a damaged slider on a separatingtype slide fastener, carefully rip the stitches at theTOP of the slide fastener, on the retainer sideonly, thus exposing the end of the tape. Removethe top stop, slip the slider off the top of the chain,and completely remove it from the bead and tape.Repair or replace the slider.

To replace the slider on a separating typeinterlocking slide fastener, thread the bead on theretainer side into the narrow end of the slider, andallow the slider to slip down the chain. Replace

the tape end and ripped stitches by hand ormachine.

To replace the slider on the top of a regular,nonseparating type interlocking slide fastener withthe aid of pull-up pliers, slip the tool over thebottom stop, clamp together, and pull upward.Close the entire chain in this manner. Thread thetwo top beads into the narrow end of the slider,holding the teeth meshed until they enter theslider. Replace the top stops, tape ends, andripped stitches.

Shortening an Interlocking Slide Fastener

To shorten an interlocking slide fastener, firstdetermine the length required. The chain shouldbe about one-half inch shorter than the openingin the material or garment. Mark the desiredlength, measuring from the bottom stop upward.Open the chain to any point below this mark andcut directly across the tape about 1 inch abovethe mark. Cut the excess teeth from the markingpoint to the end of the tape, and replace the twostops, crimping them firmly.

Installing an Interlocking Slide Fastener

The installation of an interlocking slidefastener varies with the type of job. Some arecurved, some have rounded comers, and some arehidden. The installation of a straight slide fasteneris described in the following paragraphs.

Slide Fastener Presser Foot

To install a slide fastener neatly and easily,you should use a slide fastener presser foot on thesewing machine. The slide fastener presser footserves not only as a guide for a neat row ofstitches, but also prevents the foot from ridingup on the chain.

The sewing machine manufacturer can supplya regular slide fastener presser foot (right or left)for any sewing machine, or one can be madelocally. File or grind the left side of an old presserfoot to permit sewing to within 1/8 inch of thechain.

Fabrication

When sewing, always stretch the slide fastenerand not the material, as this makes a flatter andneater job.

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239.311Figure 10-22.—Installation of a slide fastener. Step 1.

When making a bag or cover with two closedends, lay the piece of material right side down,and place the slide fastener right side down ontop of the material where the opening is to belocated. Sew a row of stitches completely aroundthe outer edge of the tape, as shown in figure10-22.

Turn the material over. Then by feeling withthe points of a pair of scissors, cut the materialdirectly down the center of the chain and cut aV at each end, as shown in figure 10-23.

Turn the edges of the material under, thusexposing the chain. Allow sufficient space betweenthe chain and the folded edge of the material toprevent the slider from rubbing the edge of thehems. Cutting the V at each end of the chainpermits the sewing of neat, square corners. (Seefigure 10-24.)

Procurement of Slide Fasteners

When requisitioning slide fasteners or slidefastener parts through the supply system, certainspecific information is necessary: type, size, grade,color, style or slider, and unit of issue are all partof this information.

239.312Figure 10-23.—Installation of a slide fastener. Step 2.

239.313Figure 10-24.—Installation of a slide fastener. Step 3.

10-19

There are two types of slide fasteners—separating and nonseparating. A nonseparating,type A, slide fastener is used where only a smallarea needs to be opened; for example, the openingin a parachute bag. A separating slide fastener,type B, is used in areas where it is necessary tospread the opening for easy access, such as on ajacket or the legs and waist of an anti-g coverall.

To determine the size or service weight of aslide fastener to be installed on a fabric assembly,consider the weight of the material and the stressthat will be applied. The size range and servicesof slide fasteners are as follows:

1. Size 0 - light service2. Size 1 - light to medium service3. Size 2- medium service4. Size 3- medium to heavy service5. Size 4- heavy service

Materials used inslide fastener constructionvary from plastic and nylon to cotton, rubber, andmetal. There are two common grades of slidefastener chains. Grade I is of brass constructionand Grade II is made of other metal alloys orsynthetic materials.

In most instances, however, you will beconcerned with fasteners that have beenconstructed from cotton fabric and metal parts.

A closely woven cotton fabric is commonlyused for the tape of a slide fastener; match thecolor of this tape to the main fabric color wheninstalling a slide fastener.

On certain items of survival equipment usingslide fasteners, it is mandatory that the sliderremain stationary where it is positioned on thechain. An accidental opening in flight of anequipment container or item of flight clothingcould cause a lot of trouble for the aircrewman.

Unintentional opening of a slide fastener thatrequires positive security is prevented by using alocking style L slider.

Illustrated in figure 10-20 are two commontypes of locking style L sliders: the pin type andthe cam type. The pin type is designed to lockwhen the pull tab is pressed flat onto the chain,thereby inserting its pin between two teeth on oneside of the chain.

The cam type is also designed to lock whenthe pull tab is pressed flat onto the chain, therebycausing friction between the chain and the cam.This action prevents any movement of the slider.

Slide fasteners installed where the movementof the slider is not critical may be equipped with

a style S, standard nonlocking slider. The styleS slider is normally used on slide fasteners whereaccidental openings do not create a problem.

The length of a slide fastener is determinedby the amount of closure required. When orderingslide fasteners from class 5325 of the FederalStock Catalog, you need to refer to the dimensioncolumn, which lists both the length of the chainand the width of the tape. The size of a slidefastener is referred to as its service weight.

Activities should specify the brand of chainfor which stops and sliders are required (Talon,Crown, or any other make).

Slide fasteners in stock are supplied in thenearest length ordered. When received, you cancut the chain to the desired length; stops can besalvaged and reused on the cut chain.

SEAMS AND KNOTS

A variety of seams and knots are presentedin the following text.

HAND-SEWN SEAMS

This is the age of great technologicaladvancements and man has come to rely heavilyon the conveniences that technology provides. Asyou know, almost everything you do involves theuse of a machine. From the housewife with herautomatic dishwasher and the computer that paysyou regularly twice each month to the sewingmachine you use to repair articles made fromfabric, technology is involved. Very few peoplein our society have the opportunity to use handskills; therefore, they search for hobbies, such asmodel aircraft building, carpentry, and leathercrafts to satisfy this desire.

You are fortunate because your job involvesusing both hand and machine skills. Very fewpeople get the opportunity to work with raw andfinished materials and have creating, fabricating,and repairing as part of their job. In yourparticular situation, not only do you use yourhands for tying knots and packing life rafts, butyou also use your hands to take the place of asewing machine. By now you have seen thatsewing is perhaps the most useful skill thefabrication and parachute specialist shoulddevelop. Few fabric maintenance jobs areperformed without some kind of sewing.Although, from your experience, you know thatmost sewing is done with a machine; you alsoknow there are occasions when machine sewing

10-20

is impractical or impossible because the design ofthe article may be such that using a machine wouldnot meet the seam specification. Not only maysome jobs be better done with hand sewing thanwith a machine, but also hand sewing is specifiedby technical order for certain jobs.

Some of the hand stitches you will use arebasting stitch, running stitch, hidden stitch,overthrow stitch, and baseball stitch. You shoulduse the one that best suits the particular job. Touse these stitches properly, you should firstbecome acquainted with the applicable definitionsand general procedures.

A stitch is a unit of thread formation. A seamconsists of a series of stitches (hand- or machine-sewn) joining two or more pieces of material. Allseams should possess strength, elasticity,durability, and a good appearance. The strengthof a seam depends upon the type of stitch used,type of thread used, number of stitches per inch,tightness of seam, construction of seam, and sizeand type of needle used. The appearance of aseam depends on how the seam is made. Eventhough you desire a good appearance, your firstconsiderations should be elasticity, durability, andstrength.

The elasticity desired in a seam is determinedby the material being sewn. If the materialpossesses an elastic quality, the seam should alsopossess this same quality. If the seam does notpossess the same elastic quality as the material,the stitches may break when stress is applied. Aseam should be as durable as the material it joins.Tightly woven fabrics are more durable and havea smoother finish; therefore, they tend to slideon one another. To prevent this sliding, set thestitches tight and deep enough into the materialto reduce wear caused by their rubbing on othersurfaces.

When hand sewing cloth, turn under one-halfinch of the material as reinforcement and insertthe needle through both plies. When hand sewingthick materials, such as leather and felt, do notturn the edges under.

To hand sew any seam, you must know howto prepare for the job. Select the proper needleand thread. Choose a thread that matches thethread of the material as nearly as possible. Usethe smallest size needle that allows the thread topass easily through the eye of the needle. Tothread the needle, pass one end of the threadthrough the eye and continue to pull it throughuntil the ends meet. The resulting double threadshould be no longer than an arm’s length. Tie abinder’s knot at the end of the doubled thread.

For sewing seams that require only one thread,pull only about 6 inches of thread through the eye,and then tie an overhand knot in the other endof the thread. Again, use no more than an arm’slength of thread.

The overhand knot is the simplest knot made.It is important because it forms a part of the manyother knots. To practice making this knot, get ashort piece of cord and make a loop in it. Thenpass the end through the loop and pull theloop tight. If two pieces of thread side byside are formed in a loop, the resulting knotis called a binder’s knot. This knot is identicalto the overhand knot except that two threads areused.

Most permanent hand-sewn seams in fabricsshould be locked with two half hitches at intervalsof 6 inches. These half hitches prevent any breakin the seam from going past an interval. Lock allseams at the end with two half hitches, a squareknot, or a surgeon’s knot. A half hitch is simplyan overhand knot whose loop passes aroundanother item, such as a thread or an edge ofmaterial. To tie the square knot, tie a simpleoverhand knot. You then tie another overhandknot in the opposite direction, locking the firstknot. The surgeon’s knot is a modified form ofthe square knot. It is the same as the square knotwith the exception of the first overhand knot,which is a double turn. This double turn keepsthe cord from slipping while the last overhandknot is made.

Yellow beeswax is applied to hand sewingthread to prevent fraying and untwisting. Use onlypure beeswax, since the impurities in other waxesmay cause oil or grease spots, which deterioratethe thread. Beeswax preserves cotton thread; besure to use it.

Other wax used in the survival equipment shopis made up of one part beeswax and one partparaffin. It is blended in a wax melting pot. Ifyou are required to perform the task of waxingan entire spool of thread, place the wax pot ona wide, level surface. Place the electric cord ofthe wax pot so that you, or other personnel in yoursection, will not walk into it. Gently lower thethread into the hot, molten wax; don’t let thethread rest on the bottom of the pot. How longyou keep the thread in the wax pot is determinedby the size and type of thread you are using.Follow these directions carefully to prevent thethread from burning or weakening because ofovercooking.

When sewing, hold the needle between yourthumb, index, and middle fingers. Push it forward

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with the thimble on your fourth finger. Keep yourfourth finger about two-thirds bent. Three fingersare needed to guide the needle accurately andswiftly from right to left. Hold the material insuch a manner that you do not tire easily; crossingyour legs and resting the material on them ishelpful. Never point the needle outward at arm’slength, because you may injure a passerby.

Purposes and Characteristicsof the Basting Stitch

The basting stitch is used only for holding pliesof material together temporarily, before machinesewing. This stitch is particularly helpful when youinstall a patch to a flight suit or a cover. Bastingstitches are removed after making the machineseam.

Two types of needles can be used forbasting-either the straight or the creed. Use thecurved needle for hard-to-get-at areas, such asbasting a patch on a cover; otherwise, the job canbe done with a straight needle. Make the bastingstitch as follows. Thread the needle with asufficient length of 16-4 thread, single or waxed.Tie an overhand knot in the end of the singlethread. Turn under the material edge one-halfinch, unless specified otherwise in the technicalorder. Make each stitch one-fourth inch in lengthand one-eighth inch from the folded edge of thematerial. At the end of the row of basting stitches,lock the last stitch with two half hitches. Cut thethread one-fourth inch from the knot. Figure10-25 illustrates the formation of the bastingstitch.

Hand Sewing the Running Stitch

You can use a running stitch as a substitutefor a machine-sewn seam. It is designed to be apermanent stitch, when a sewing machine is notavailable. Use a straight needle threaded withsingle- or doubled-waxed cord or thread. Tie aknot at the end of the cord. The material shouldbe turned under one-half inch. Insert the needleinside the one-half inch fold of one ply and pushit through the three remaining plies so the startingknot will be hidden. Continue sewing the piecestogether by using the basting stitch. When youcome to the end of the row, turn the materialaround and go back in the opposite direction,filling in the empty spaces as you sew, as shownin figure 10-26. These two rows together becomethe running stitch. Use four stitches per inch (eachstitch one-fourth inch long) and one-eighth inch

Figure 10-25.-Basting stitch.

from the foldedinches.

Keep enough

Figure 10-26.-Running stitch.

edge. Lock the seam every 6

tension on the thread to formfirm, well-set stitches. When you make the laststitch, insert the needle through two piles andbring it out in the center of the plies. Make twohalf hitches around the stitch extending from thesecond layer to the third layer of material.

Hand-sewn Overthrow Stitch

You use the overthrow stitch to attach metalparts, such as cones and eyelet. For this type ofattachment, a sewing machine is not practical. Theoverthrow stitch is also used for harness tackings.A curved needle is used when the stitch can onlybe sewn from one side of the fabric. Fold the

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material under one-half inch for reinforcement.Insert the needle in such a manner that the knotwill be between the two pieces of material. Formthe overthrow stitch by inserting the needleone-eighth inch from the folded edge and at right

Figure 10-27.—Overthrow stitch.

angles to the material, as shown in figure 10-27.Make each stitch by inserting the needle from thesame side as the previous stitch. For best results,make six stitches per inch. At the end of the row,tie off the thread with two half hitches.

Sewing the Baseball Stitch

The baseball stitch is a useful, permanentstitch, because it is very flexible and very elastic.It pulls the edges of material (cloth or leather)evenly together to form a flat surface, and it isused for repair or closing an opening. The threadlies on both the top and bottom edges of thematerial. Like lacing, it can be pulled as tightlyas desired. Usually a curved needle is used to sewthe baseball stitch.

Thread the needle with the required type ofcord, waxed and tied with a knot at the end. Ifit is fabric to be sewn, rather than leather, turnthe edges under one-half inch. Insert the needlethrough the fold of one ply of material to hidethe knot, as shown in figure 10-28. Insert the

239.379Figure 10-28.—Baseball stitch.

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239.256AFigure 10-29.—Baseball stitch (top view.

needle from the outside of the lower ply and bringit out the center of the plies, forming a straightoverthrow stitch at the beginning of the seam, asshown in view B of figure 10-28. Start the baseballstitch by inserting the needle in the center of theplies toward the outside of the opposite piece ofmaterial, as shown in view C of figure 10-28.Proceed with the baseball stitch along the foldededges of the fabric (or the edges of the leather),as shown in figure 10-29. Insert the needle fromthe inside of the folded edges, only one-sixth inchfrom the folded edge, as shown in views D, E,and F of figure 10-28. Keep enough tension onthe thread to remove all loops and slack thread.Do not apply too much tension because this tendsto pucker or draw the seam out of line. Every timeyou sew 6 inches of the baseball stitch, make alock knot, as shown in figure 10-30. After the lasttwo stitches of the baseball stitch, finish with astraight overthrow stitch and two half hitches.

Use of the Hand-sewn Hidden Stitchand the Needle Used

The hidden stitch is usually used to makerepairs on upholstery and on clothing where goodappearance is important. To make this stitch,select a 2 1/2-inch curved needle and a length ofsuitable thread. Thread the needle to sew with asingle thread and tie a knot in the long end. Foldunder one-half inch of material and place it onthe other piece of material, as shown in figure10-31. Start the stitch by pushing the needlethrough the back of the fold, about one-eighth

239.256BFigure 10-30.—Forming a lock knot for the baseball stitch.

inch from the end. Pull the needle through thebottom material at a point directly below wherethe needle came out of the fold. Guide the needleso that the point comes out again about one-fourth inch along the line of the seam. The pointshould come out directly below the creased edge,as shown in view A of figure 10-31. Pull the needleand thread out to draw the stitch tight. Push theneedle into the front edge of the fold directlyabove the point where the needle came out of thebottom material. Guide the needle point along theinside of the fold so that it again comes out thecreased edge about one-fourth inch from whereit entered, as shown in view B of figure 10-31. Pullthe stitch tight and repeat the previous steps untilthe end is reached. Finish the seam off by comingback one stitch (through the opposite material)so that the needle reappears alongside the exposedthread of the next-to-the-last stitch. Tie two halfhitches around the exposed thread.

MACHINE-SEWN SEAMS

Chances are you have been accomplishingsewing projects since you arrived at your newassignment. Then again, you may have done nosewing at all. The amount of sewing done in yourshop depends upon the mission of your base. Ifyour unit does much fabrication, then youprobably will do quite a lot of machine sewing.

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Figure 10-31.—Hidden stitch.239.380

In this section, we discuss techniques concerningmachine-sewn seams. While there is generally nooption in choosing a hand-sewn seam, there aremany options in choosing a machine seam.

Advantages and Characteristicsof a Machine-Sewn Seam

Machine seams or stitchings have thefollowing advantages over hand-sewn seams: (1)speed, (2) appearance, and (3) uniformity oftension. Their desirable characteristics are asfollows:

STRENGTH. Strength of a seam of stitchingdepends on the type of thread, stitch type, numberof stitches per inch, the construction and tightnessof the seam, and the size and type of needle pointused. The strength of the seam should equal thatof the material it joins. Use only the materialspecified for the assembly in the applicabletechnical order.

ELASTICITY AND FLEXIBILITY. Elas-ticity and flexibility depend on the stretchingqualities of the material used, the quality andtension of the thread, the length of the stitch, andtype of seam or stitch used.

DURABILITY. Durability is determined bythe wearing qualities of the material, the qualityof the thread used, and proper tension to setstitches well into the material to reduce abrasions.Relationship between the elasticity of the seamand the elasticity of the material is very importantin determining durability.

SECURITY. The security of a seam orstitching depends chiefly on the stitch type andits ability to resist unraveling. The stitch must bewell set in the material to prevent snagging, whichcan cause thread breakage and unravel some typesof stitches. Seam “run offs” weaken a seam. Allseam ends should be backstitched or anchored(backstitched and overstitched) to prevent theseams from unraveling, as illustrated in figure10-32.

APPEARANCE. The appearance of a seamis controlled by its construction and neatness ofworkmanship; however, appearance is of lessimportance than any of the four factors explainedpreviously—strength, elasticity, durability, andsecurity. Size and type of thread and length ofstitch may also affect appearance.

Meanings and Symbols ofMachine-Sewn Basic Stitches

Meanings and symbols of basic machine-sewnstitches are discussed in the following paragraphs.

Figure 10-32.—Properly anchored machine seam.

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STITCH. A stitch is one unit of threadformation resulting from passing a thread throughmaterial at uniformly spaced intervals. Theclass of stitch is indicated by a specifica-tion number; for example, 301, which specifiesa United States Standard Lockstitch (one lockknot for each stitch). The class 31 and 111sewing machines sew a United States StandardLockstitch 301.

SEAM. A seam is a joint consisting of asequence of stitches uniting two or more piecesof material.

STITCHING. A stitching consists of asequence of stitches for finishing an edge, forornamental purposes, or both in preparing partsfor assembling.

The seam or stitch formation is indicated bya symbol consisting of three parts:

o f

NOTE: The three parts follow the three-digit number showing the type stitch themachine makes.

1. The frost part denotes the class and consiststwo uppercase letters; for example, SS.2. The second part denotes the type or the

class of the seam or stitch formation and consistsof one or more lowercase letters; for example, a.

3. The third part denotes the number of rowsof stitches used and consists of one or moreArabic numerals preceded by a dash; for example,– 1 .

The complete seam specification for theexamples given becomes 301-SSa-1. (Rememberthat the “’301” is the machine class of stitch.

There are places where one seam will be betterthan others. Experience has shown certain seamsare best to serve a certain purpose. These seamshave been standardized so that people who dosewing can turn out the same type of work.Standardization makes it possible to makedrawings and blueprints that can specify a desiredseam. This way, no matter who does the job, thefinished article turns out to be as strong anddurable as the designer wanted it.

Uses of Varying Classes ofMachine-sewn Seams and Stitchings

The uses of varying classes of machine-sewnseams and stitchings are covered in the followingmaterial.

Figure 10-33.—Superimposed seam.

CLASSES OF SEAMS.— The three classes ofseams are SS (superimposed seams), LS (lappedseams), and BS (bound seams).

Class SS, Superimposed Seams.— These seamsare formed by placing one ply of material aboveanother with the edges together and the seamalong one side. Superimposed seams are usuallymade with two plies of material, although morethan two plies can be used for special projects.The edges may be folded under, but they are neveroverlapped when the stitching is made. Types ofsuperimposed seams are SSa-1 and SSc-2, asshown in figure 10-33.

1. The SSa-1 seam is the simplest method ofjoining two or more pieces of material. It is alsoused as the first step in the formation of otherseams, such as the LSak-2 seam.

2. The SSc-2 seam is used for making manydifferent types of covers. It is also used in makingchannels for sash cord when making handles oncarrying bags and cases.

Class LS, Lapped Seams.— You form the classLS seam by overlapping the material a sufficientdistance and stitching with one or more rows ofsewing, as shown in the cross-sectional views infigure 10-34. Types of lapped seams are LSc-2,LSc-4, LSd-1, and LSak-2.

1. The LSc-2 seam is used for the sectionalseams and the LSc-4 for the channel seams ofparachute canopy. The interlocking of the foldsmakes the LSc seams the strongest of the seamformations.

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Figure 10-34.—Lapped seam.

2. The LSd-1 seam, as shown in figure 10-34,is used in sewing pockets or patches. Also, usethe seam to patch small holes.

3. The LSak-2 seam, as shown in figure 10-34,is used for finishing seams of covers for shopequipment.

Class BS, Bound Seams.— BSa-2 seams aremade by folding binding strips or tapes over theedges of the material to reinforce and finish theedges. Use the BSa-2 seam, as shown in figure10-35, to bind the edges of tool aprons,reinforcement panels etc. Most soundproofing isbound with 3/4-inch tape using the BSa-2 seam.

CLASS OF STITCHING.— You form classEF (edge finishing) stitching by using the edge ofa single ply of material to make the hem. TheEFb-4 stitching, as shown in figure 10-36, is madeby folding the edge back twice, thus turning thecut edge inside the second fold to prevent frayingand to reinforce the hem. The hem may alsoinclude a piece of reinforcing tape, plain ortubular webbing for adding strength. All seams

Figure 10-35.—Bound seam.

Figure 10-36.—Edge finishing stitching.

and stitches pictured are used in the survivalequipment shop for modification and repair workon the parachute canopy, pack, seat, and backpads, or for making covers and bags for aircraft,shop equipment, and tools.

Appropriate Spacing ofMachine-sewn Seams

The following rules will help you to spacecorrectly more than one line of stitching and toplace a seam the correct distance from the edge:

1. Sew regular binding tape one-sixteenth ofan inch from the selvage edge of the tape.

2. Sew heavier tapes from one-sixteenth toone-eighth inch from the edge. Sew the raw endsof the tapes one-fourth inch from the raw edge.

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3. Sew horsehide and thin leathers one-eighth inch from the edge in patching, trimming,etc.

4. Sew the raw edges of 8 to 15 ounce duckone-half inch from the edge.

5. Fold the material no less than one-halfinch for reinforcement.

6. Sew the folded edges of 8 to 15 ounceduck one-eighth inch from the folded edge.

7. Make the second and succeeding rows ofstitches one-fourth inch apart. In heavier material,it is sometimes desirable to separate the rows asmuch as three-eighths of an inch.

8. Heavy duck, heavy fabric, or the heavierleathers may be sewn approximately one-fourthinch from folded edges for best results, while theraw edges of such heavy fabrics need at least one-half inch to three-fourths inch seams for security.

9. Sew light nylon or aircraft fabric one-sixteenth inch from the folded edge. Raw edgesof these light materials are seldom sewn together,except as the first step of another seam.

10. When you are sewing a row of stitches andthe thread breaks, start sewing again one-half inchbehind the break, and sew on top of the existingstitches. This is called backstitching.

The stitches that form the various classes ofseams should be tight, even, and well-set into thematerial. An understanding of how the machinefunctions to form the stitch and feed the materialprovides the basis for you to sew high-qualityseams consistently.

KNOTS

A boy scout’s first achievement is to learn totie knots. Knots are necessary to manyactivities-camping, boating, mountain climbing,and parachute rigging. Different knots servedifferent purposes. For instance, a hangmanwould be out of a job if he forgot how to makea slip knot. A doctor would have trouble sewinghis patient up after an appendectomy if he didn’tmake a proper surgeon’s knot. Also, you couldnever pack a parachute correctly without aworking knowledge of several different types ofknots.

Some specialists have a tendency not to be asconcerned about knots as they are about otheritems involved in servicing parachutes. Think ofknots as the treads (and the depth of the treads)on your automobile tires. Sure, the tire canperform without treads. But, if the tires are goingto grip the road surface and stop the automobile

in the shortest time and distance possible, theyrequire good tread depth. Tire treads are designedto meet many performance requirements. Thesame principles apply to knots used in parachuterigging.

Make sure that all knots and tackings arechanged as often as possible. Their “tread”deteriorates and becomes loose. Parachutes aredesigned to perform under the most unpredictablesituations, at speeds and configurations too greatto imagine. One poorly made knot and tackingcould cause burned suspension lines, excessiveopening shock, or oscillation-all of which couldresult in the failure of the parachute. Remember,no matter how small the task, treat each area ofthe parachute with the greatest care and concern.

The type of knot used in assemblingcomponent parts of parachutes depends on thepurpose for which the knot is intended, thestrength required, and the kind of thread, rope,or cord that is to be used. Remember, knots,hitches, and turns decrease the tensile strength ofrope, cord, or thread, as shown in figure 10-37.Some knots are tied for the purpose of breakingduring parachute deployment, and other knots aretied so as not to break. This is why it is soimportant that only the specified knots be usedfor a particular job. The following text discussesthe knots you will have to tie as you go about yourjob of servicing parachute assemblies.

Overhand knot

The overhand knot is the simplest knot made,as shown in figure 10-38. It is very important,

Figure 10-37.—Tensile strength decreased by knot.

Figure 10-38.—Overhand knot.

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Figure 10-39.—Binder’s knot.

however, since it forms a part of many otherknots. You use the overhand knot at the end ofa single thread when you are hand sewing.

Binder’s Knot

A binder’s knot is the simplest method ofjoining two cords or threads together, as shownin figure 10-39. Use it at the end of a double cordwhen hand sewing to prevent the cord frompulling through the material as you sew.

Square Knot

The square knot is the most common knot forjoining two ropes or cords, as shown in figure10-40. It can be easily and quickly tied and untied,and it is secure and reliable except when made withropes and cords of two different sizes.

Surgeon’s Knot

The surgeon’s knot is a modified form of thesquare knot (figs. 10-41 and 10-42). In fact, it

Figure 10-42.—Surgeon’s and lock knot.

is the same as the square knot, with the exceptionof the first overhand knot, which is a double turn.This double turn keeps the cord from slippingwhile the last overhand knot is tied.

Bowline

The bowline is used to connect the reserveparachute pilot chute bridle line to the canopy ventlines (fig. 10-43).

Half Hitch

The half hitch, shown in figure 10-44, is usedto form the tie for the safety ties on ripcord pins

3.218(3D)Figure 10-43.—Bowline.

Figure 10-40.—Square knot.

Figure 10-41.—Surgeon’s knot.3.221

Figure 10-44.—Round knot and two half hitches.

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on the various types of personnel, cargo, anddeceleration parachutes. Normally, three halfhitches in a series are used for the safety tie.

Clove Hitch

The clove hitch, shown in figure 10-45, is usedto secure the suspension lines to the connectorlinks on many parachute assemblies.

You know how to tie the most common knotsused in parachute rigging. For even greatersecurity, these knots can be modified to formseveral other knots. The lock knot is an overhandknot tied adjacent to many other knots. For

example, to prevent the square and lock knots orthe surgeon’s and lock knot from slipping, youtie overhand knots at each end of the thread orcord. Also, the overhand knot can be tied in aseries. The same applies to the surgeon’s knot.The binder’s knot leaves a loose end to form aslip knot, which is used to temporarily tie anexcess amount of cord. The AS28A deploymentbag uses this type of knot. Also, when you securethe automatic ripcord release’s arming knot guideon the automatic seat style parachute, you use aslip knot tied off with a lock knot. The specificknots you use are determined by the engineers whodesign, test, and establish criteria for the operationand function of parachute assemblies.

3.220Figure 10-45.—Tying a clove hitch.

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CHAPTER 11

OXYGEN COMPONENTS TEST STANDS

Learning Objective: Upon completion of this chapter, you will be able toidentify, maintain, and perform periodic inspections on oxygen componentstest stands.

Aircrew Survival Equipmentmen are respon-sible for shop testing aircraft oxygen systemcomponents, including regulators, emergencyoxygen systems, and other items. The AME isresponsible for checking system components inthe aircraft; however, in case of a suspectedmalfunction and for periodic maintenance testing,the component is removed from the aircraft andbrought to the oxygen shop where it is tested bythe PR. This testing is accomplished with the useof various types of test equipment, some of whichare discussed in this chapter.

OXYGEN

No one can live without sufficient quantitiesof food, water, and oxygen. Of the three, oxygenis by far the most urgently needed. If necessary,a well-nourished individual can go without foodfor many days or weeks, living on what is storedin the body. The need for water is moreimmediate, but still the need does not becomecritical for several days. The amount of oxygenin the body is limited at best to a few minutessupply. When that supply is exhausted, death isprompt and inevitable.

Oxygen starvation affects a pilot or air-crewman in much the same way that it affects anaircraft engine—neither can function without it.The engine requires oxygen for burning the fuelthat keeps it going. An engine designed for low-altitude operation loses power and performspoorly at high altitudes. High-altitude operationdemands a means of supplying air at higherpressure to give the engine enough oxygen for thecombustion of its fuel. The supercharger orcompressor performs this function.

The combustion of fuel in the human bodyis the source of energy for everything the aviator

is required to do with his muscles, with his eyes,and with his brain. As the aircraft climbs, theamount of oxygen per unit of volume of airdecreases; therefore, the aviator’s oxygen intakeis reduced. Unless he/she breathes additionaloxygen, the eyes, the brain, and the musclesbegin to fail. The body is designed for low-altitude operation and will not give satisfactoryperformance unless it is supplied the full amountof oxygen that it requires. Like the engine, thebody requires a means of having this oxygensupplied to it in greater amounts or under greaterpressure. This need is satisfied by the use ofsupplemental oxygen supplied directly to therespiratory system through an oxygen mask, bypressurizing the aircraft to an atmosphericpressure equivalent to that of safebreathingaltitudes, or both.

For purposes of illustration, an aviator’s lungsmay be compared to a bottle of air. If an openbottle is placed in an aircraft at sea level, airescapes from it continuously as the aircraftascends. The air pressure at 18,000 feet is onlyhalf the amount as that at sea level; therefore, at18,000 feet the bottle is subjected to only half theatmospheric pressure it was subjected to at sealevel. For this reason, it will contain only half theoxygen molecules it had when on the ground.

In like fashion, an aviator’s lungs containless and less air as he/she ascends, andcorrespondingly less oxygen. Thus, the use ofsupplemental oxygen is an absolute necessity onhigh-altitude flights. Above 35,000 feet, normalactivity is possible up to about 43,000 feet by useof positive pressure equipment. This equipmentconsists of a “supercharger” arrangement bywhich the oxygen is supplied to the mask undera pressure slightly higher than that of thesurrounding atmosphere. Upon inhalation, the

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oxygen is forced into the lungs by the systempressure. Upon exhalation, the oxygen flow is shutoff automatically so that carbon dioxide canbe expelled from the mask. Normal activityis possible to 50,000 feet with the use of apressure breathing oxygen regulator. Above50,000 feet, the only adequate provision for thesafety of the aviator is pressurization of the en-tire body.

Up to about 35,000 feet, an aviator can keepa sufficient concentration of oxygen in his/herlungs to permit normal activity by use of demandoxygen equipment, which supplies oxygen upondemand (inhalation). The oxygen received bythe body on each inhalation is diluted withdecreasing amounts of air up to about 30,000 feet.Above this altitude up to about 35,000 feet, thisequipment provides 100-percent oxygen. At about35,000 feet, inhalation alone will not provideenough oxygen with this equipment.

EFFECTS OF HYPOXIA

A decrease in the amount of oxygen per unitvolume of air results in an insufficient amountof oxygen entering the bloodstream. The bodyreacts to this condition rapidly. This deficit inoxygen is called HYPOXIA. A complete lack ofoxygen, which causes death, is called ANOXIA.If the body is returned to its normal oxygensupply, one may recover from hypoxia, but can-not recover from anoxia.

Many persons are not aware of the enormousincrease in the need for oxygen caused by anincrease in physical activity. Strenuous calisthenicsor a cross-country run results in deep and rapidbreathing. Even so mild an exercise as getting upand walking around a room may double the airintake. In the case of the aviator, a leakingoxygen mask that may go completely unnoticedwhile the wearer is at rest may lead to collapseand unconsciousness when he/she attempts tomove about from one station to another in theaircraft. A walkaround (portable) oxygen bottlesufficient for 24 minutes of quiet breathing maybe emptied by 17 minutes of use when the useris moving about the aircraft.

People differ in their reactions to hunger,thirst, and other sensations. Even an individual’sreactions vary from time to time under differentcircumstances. Illness, pain, fear, excessive heator cold, and many other factors govern what the

response will be in each particular case. The samething is true of individual reactions to oxygenstarvation. The effects of a certain degree ofhypoxia on a given person cannot be accuratelypredicted. For instance, a person maybe relativelyresistant on one day, but highly susceptible thenext.

It is difficult to detect hypoxia, because itsvictim is seldom able to judge how seriouslyhe/she is affected, or often that he/she is affectedat all. The unpleasant sensations experienced insuffocation are absent in the case of hypoxia.Blurring of vision, slight shortness of breath, avague weak feeling, and a little dizziness are theonly warnings. Even these may be absent or soslight as to be unnoticeable.

While still conscious, the aviator may lose allsense of time and spend his last moments ofconsciousness in some apparently meaninglessactivity. In such a condition, the aviator is amenace to the crew as well as to himself. Sincethe aviator understands that it is the reduced airpressure at higher altitudes that determines theeffect upon the body, he/she depends upon thealtimeter rather than sensations or judgment totell when oxygen is needed.

CHARACTERISTICS OF OXYGEN

Oxygen, in its natural state, is a colorless,odorless, and tasteless gas. Oxygen is consideredto be the most important to life of all the elements.It forms about 21 percent of the atmosphere byvolume and 23 percent by weight.

Of all the elements in the universe, oxygen isthe most plentiful. It makes up nearly one-halfof the earth’s crust and approximately one-fifthof the air we breathe.

Oxygen combines with most of the otherelements. The combining of an element withoxygen is called oxidation. Combustion is simplyrapid oxidation. In almost all oxidations, heat isgiven off. In combustion, the heat is given off sorapidly it does not have time to be carried away;the temperature rises extremely high, and a flameappears.

Some examples of slow oxidation are therusting of iron, drying of paints, and the changingof alcohol into vinegar. Even fuels in storage are

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slowly oxidized, the heat usually being carriedaway fast enough; however, when the heat can-not easily escape, the temperature may risedangerously and a fire will break out. This iscalled spontaneous combustion.

Oxygen does not bum, but does supportcombustion. Nitrogen neither burns nor supportscombustion. Therefore, combustible materialsbum more readily and more vigorously in oxygenthan in air, since air is composed of about78 percent nitrogen by volume and only about 21percent oxygen.

In addition to existing as a gas, oxygen canexist as a liquid and as a solid. Liquid oxygen ispale blue in color. It flows like water, and weighs9.54 pounds per gallon.

Liquid oxygen, commonly referred to as LOX,is normally obtained by a combined cooling andpressurization process. When the temperature ofgaseous oxygen is lowered to – 182°F under about750 psi pressure, it will begin to form into a liquid.When the temperature is lowered to – 297°F, itwill remain a liquid under normal atmosphericpressure.

Once converted into a liquid, oxygen willremain in its liquid state as long as the temperatureis maintained below – 297 ‘F. The liquid has anexpansion ratio of 862 to 1, which means that onevolume of liquid oxygen will expand 862 timeswhen converted to a gas at atmospheric pressure.Thus, 1 liter of liquid oxygen produces 862 litersof gaseous oxygen.

Until a few years ago, all oxygen carried innaval aircraft was in the gaseous state. As flightdurations increased, however, it was found thatthe weight and space problems involved withcarrying increasing amounts of gaseous oxygenwere becoming intolerable. LOX has proven theanswer to these problems. In its liquid state,oxygen can be “packed” into containers small andlight enough to be carried even in fighter-type air-craft without weight and space penalty.

In the aircraft, oxygen in the liquid state iscarried in a container called a converter. This isa double-walled, vacuum-insulated containersimilar to the common Thermos bottle. Theconverter is equipped with the necessary valvesand tubing for vaporizing the liquid and warm-ing the gas to cockpit temperatures.

TYPES OF OXYGEN

Aviator’s breathing oxygen (MIL-O-27210C)is supplied in two types (I and II). Type I isgaseous oxygen, and type 11 is LOX. Oxygenprocured under the above specification is requiredto be 99.5 percent pure. The water vapor contentmust not be more than 0.02 milligram per literwhen tested at 70°F and at sea level pressure. Thisis practically bone dry.

Technical oxygen, both gaseous and liquid, isprocured under specification BB-0-925. Themoisture content of technical oxygen is not asrigidly controlled as that of breathing oxygen;therefore, the technical grade should never be usedin aircraft oxygen systems.

The extremely low moisture content requiredof breathing oxygen is not to avoid physicalinjury to the body, but to ensure proper opera-tion of the oxygen system. Air containing ahigh percentage of moisture can be breathedindefinitely without any serious ill effects.However, the moisture affects the aircraft oxygensystem in the small orifices and passages in theregulator. Freezing temperatures can clog thesystem with ice and prevent oxygen from reachingthe user. Therefore, extreme precautions must betaken to safeguard against the hazards of watervapor in oxygen systems.

OXYGEN COMPONENTTEST STAND 1172AS100

Regulator test stands are designed for testingoxygen regulators for flow capacities, oxygenconcentrations, pressure characteristics, andvarious leakage tests at different simulatedaltitudes. There are several models of teststands capable of testing the oxygen regulators,converters, etc. We will cover only the ones thatmost oxygen shops throughout the Navy use. Ifyou happen to work in an oxygen shop that isusing outdated equipment, ask the petty officerin charge of the work center to show you theliterature that covers that equipment. In this ratetraining manual, we will discuss only the1172AS100 test stand used for testing oxygenregulators.

The Oxygen System Components Test Stand,Model 1172AS100, tests and evaluates miniatureoxygen breathing regulators as well as panel and

11-3

console mounted oxygen breathing regulators.(See figure 11-1.)

Oxygen system components test stands aresupplied by more than one manufacturer. Theoperation, maintenance, and parts are, with a fewminor exceptions, identical. Where there aredifferences in applications, or where operationalprocedures differ, they will redescribed in theindividual regulator chapters of NAVAIRPublication 13-1-6.4. Therefore, before youattempt to test any oxygen component, you shouldrefer to that manual.

The oxygen system components test standconsists of a nitrogen pressure source and avacuum system. It includes the valving andinstrumentation necessary to measure, test, andevaluate the performance and operatingcharacteristics of oxygen system components ataltitudes up to 150,000 feet.

Performance of the test stand is dependentupon the skill of the operator. You mustbe thoroughly familiar with the instruments,controls, and connections that comprise thesystems that are incorporated within the test stand(fig. 11-1).

ON/OFF VALVES

There are two ON/OFF valves on the teststand. These valves are colored red and have twopositions—ON and OFF. The first valve is calledthe inlet pressure ON/OFF valve (L). This valvepermits a flow of regulated high-or low-pressurenitrogen to the input connection (18) located in-side the altitude chamber. The second ON/OFFvalve is called the Leakage ON/OFF valve (G).This valve permits a flow of regulated low-pressure nitrogen gas (N2) through the selectedin-system rotameter (7) or (8). You select eitherthe low-range or the high-range rotameter byusing the leakage selector valve (F). Valve (G),the leakage ON/OFF valve, also permits a supplyof N2 to go to the input connection (18) insidethe chamber. The only time you will be usingON/OFF valve (G) is when you are adjusting thebleed on a miniature oxygen regulator (this iscovered in the NAVAIR 13-1-6.4) and when youare measuring leakage on oxygen components.

SELECTOR VALVES

As you look at the Model 1172AS100 teststand, you may think that with all those differentvalves, gauges, rotameters, and connections thatyou could never operate it. However, by operating

only four selector valves, you can direct the flowof N2 to perform the basic functions of the stand.These valves are M, O, D, and F, shown in figure11-1.

The FLOW SELECTOR valve (M) has twopositions—CONTROLLER and REGULATOR.When this valve is placed in the REGULATORposition, and you open the OUTPUT valve (C),the flow is routed directly from the item undertest through the piezometer (26) and OUTPUTport (23) to the vacuum pump. When theselector valve is placed in the CONTROLLERposition, the flow is routed through the suitsimulator tank.

The REFERENCE PRESSURE SELECTORvalve (0) is a two-position valve. It referencespressure to either the altitude chamber orthe suit simulator tank from LOW RANGEALTIMETER (13).

The PRESSURE SELECTOR valve (D) hastwo positions—H2O (water) and Hg (mercury).In the Hg position, only mercury pressure can beread. In the H2O position, either inches of waterpressure (positive pressure) or inches of watersuction (negative pressure) can be read.

The LEAKAGE SELECTOR valve (F) hastwo positions—HIGH and LOW. It routesregulated low pressure through the in-systemrotameters. When the valve is placed in the LOWposition, leakage is indicated on rotameter (7).The LEAKAGE SELECTOR valve (F) is alwaysleft in the HIGH position unless you are readinga leak or bleed below 200 cubic centimeters(CCM). This is done to prevent damage to thelow-range rotameter in the event you develop asevere leak.

VOL-O-FLO ELEMENTS

To understand the function of some of thevalves discussed in the following paragraphs, itis necessary to first understand the function ofthe Vol-O-Flo elements installed between certaincontrol valves and their indicating manometers.There are three Vol-O-Flo elements installed onthe test stand. The input Vol-O-Flo works in con-junction with INPUT valve (A) and INPUTFLOW manometer (2). The output Vol-O-Flo isused with OUTPUT valve (C) and OUTPUTFLOW manometer (l). The vent flow Vol-O-Flois used with either the VENT PRESSURE valve(H) or the VENT AMBIENT valve (1) and theVENT FLOW manometer (3).

The Vol-O-Flo elements have two taps—onenear the inlet end and one near the outlet end.

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239.476Figure 11-1.–Controls and indicators for Oxygen System Components Test Stand Model 117AS100.

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(See figure 11-2.) Baffles inside the element createa flow restriction. As air or nitrogen enters theelement, a pressure buildup is created at the inletend; as it flows past the baffles, a pressure dropoccurs at the outlet end. The inlet (pressurebuildup) tap is connected to the bottom of the in-dicating manometer, and the outlet (pressuredrop) tap is connected to the top of themanometer. As the control valve is opened, gasflows from the valve through the Vol-O-Flo, andthe pressure drop thus created allows the fluid inthe manometer to rise. The operator reads theamount of flow passing through the V0l-O-Floon the indicating manometer.

CONTROL VALVES

A control valve regulates, or restricts, aspecified flow. Two types of control valves,measuring and nonmeasuring, are used on the teststand. Measuring control valves have measuringdevices (gauges or manometers) to visuallymeasure the flow through the valve as it is opened.Nonmeasuring control valves have no indicatingdevices. There are six measuring and threenonmeasuring control valves on the test stand.

Measuring Control Valves

The measuring control valves (fig. 1 l-l) areas follows:

1. The INPUT valve (A) allows a measurableflow of air into the altitude chamber. It can only

be used during simulated altitude conditions. Asthe chamber altitude increases, pressure inside thechamber decreases, and the ambient air pressureoutside the chamber is greater. When valve (A)is opened, air from outside the chamber flowsthrough valve (A); through the input Vol-O-Floelement, indicating the amount of air flow on theINPUT FLOW manometer (2); and through theINPUT port (22) into the chamber.

2. The VACUUM CONTROL valve (B1) onModel 1172AS100 allows direct evacuation of thealtitude chamber to the desired simulated altitudeby decreasing pressure in this chamber.

3. The OUTPUT valve (C), when opened,draws a direct flow from the item under testthrough the piezometer (26), OUTPUT port (23),FLOW SELECTOR valve (M) and the outputVol-O-Flo element to the vacuum pump. As theflow passes through the output Vol-O-Flo, thepressure is displayed on the OUTPUT FLOWmanometer (1).

4. The LEAKAGE CONTROL valve (E)controls the flow to the LOW-PRESSUREconnection (19), which is located inside thechamber. As the name of the valve implies, it isused to perform various leak tests on oxygencomponents. When you use the LEAKAGECONTROL valve (E) to perform leakage tests oncomponents, a line with bayonet fittings mustbe installed between the LOW-PRESSUREconnection (19) and the REFERENCE-TAPconnection (21 ). This allows the flow passing

Figure 11-2.—VOI-O-FIO element.

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239.477

through valve (E) to be indicated on PRES-SURE/SUCTION manometer (4 ) or Hgmanometer (5), whichever you have selected. Anyleakage would be registered on rotameters (7) or(8).

5. The VENT PRESSURE valve (H) controlsa vent flow of low pressure through the suitsimulator tank to the item under test at sea level.When valve (H) is opened, nitrogen (N2) flowsthrough the vent flow Vol-O-Flo element, and isindicated on VENT FLOW manometer (3). Theflow then passes to the suit simulator tank,through FLOW SELECTOR valve (M), OUT-PUT connection (23) and piezometer (26) to theitem under test. Valve (H) is primarily used fortesting relief valves.

6. The VENT AMBIENT valve (I) serves thesame purpose as VENT PRESSURE valve (H),except that valve (H) is used at sea level withsupply pressure, while valve (I) is used at altitudeand uses ambient air as the pressure source toconserve N2. Therefore, valve (I) can beconsidered an economizer valve, used only “ataltitude.”

Nonmeasunng Control Valves

The nonmeasuring valves (fig. 11-1) areopened only as much as necessary. Flow throughthese valves cannot be measured or gauged. Thenonmeasuring valves are as follows:

1. The FLUTTER DAMPENER valve (J)allows an opening from the suit simulator tankto the line connecting FLOW SELECTOR valve(M) and OUTPUT valve (C). It acts as adampener to prevent fluttering of specificregulator diaphragms during testing, and allowsa flow to be drawn from a test item through thesuit simulator tank when FLOW SELECTORvalve (M) is in the CONTROLLER position.

2. The CHAMBER BLEED valve (K) is usedto bring the chamber to sea level from a simulatedaltitude.

3. The SYSTEM BLEED valve (S) is used tobleed N2 pressure from systems of the test standthrough SYSTEM BLEED port (16). On laterconfigurations of Model 1172AS100, SYSTEMBLEED port (16) has been deleted. N2 pressureis bled directly from a port incorporated in theSYSTEM BLEED valve (S).

SHUTOFF VALVES

There is only one shutoff valve on the1172AS100 test stand (fig. 1 l-l). It is the SUIT

SIMULATOR REFERENCE SHUTOFF valve(R). It is used to prevent damage to other com-ponents. The SUIT SIMULATOR REFERENCESHUTOFF valve shuts off the suit simulator tankfrom REFERENCE PRESSURE SELECTORvalve (0) and HELMET REFERENCE TAP (24).When you use a shutoff valve, you should fullyopen the valve, and then turn it back one-fourthturn.

CAUTION

IF SUIT SIMULATOR VALVE (R) ISLEFT OPEN WITH REFERENCE PRES-SURE SELECTOR VALVE (0) IN THESUIT SIMULATOR TANK POSITION,DAMAGE COULD OCCUR TO LOWRANGE ALTM (13) IF EXCESSIVEPRESSURE IS APPLIED TO IT WITHVENT PRESSURE VALVE (H).

REGULATORS

There are two regulators on the 1172AS100test stand (fig. 11-1). They control the supplypressure to the specific system being used. Theregulators are as follows:

1. The HIGH PRESSURE REGULATOR(Q), which is pneumatically operated. It suppliesregulated high pressures from 250 pounds persquare inch, gauge (psig) to the maximum capacityof the supply cylinder being used. Regulator (Q)has three positions—LOAD, NEUTRAL, andVENT. It is spring loaded in the NEUTRAL posi-tion. Pressure being loaded is indicated onREGULATED HIGH PRESSURE gauge (10).

2. The LOW PRESSURE REGULATOR(N), which is mechanically operated, suppliesregulated low pressure to the item under test, thein-system rotameters, and the suit simulator tank.Regulator (N) has a range of 0 to 180 psig. Thepressure being loaded is displayed onREGULATED LOW PRESSURE gauge (1 1),and is also displayed on N2 INPUT gauge (27)when the INLET PRESSURE ON/OFF valve (L)is in the ON position.

GAUGES AND INDICATORS

Gauges and indicators incorporated in the teststand (fig. 11-1 ) indicate pressures or flows. Someindicate in pounds per square inch, gauge (psig),some in feet, inches of mercury (inches Hg),

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millimeters of mercury (mm Hg), inches of water(inches H2O), or cubic centimeters per minute(CCM). Their functions are self-explanatory.

1. The SUPPLY PRESSURE gauge (9) is a0 to 3,000 psig gauge and indicates supply cylinderpressure.

2. The REGULATED HIGH PRESSUREgauge (10) is a 0 to 3,000 psig gauge and indicatesregulated high pressure.

3. The REGULATED LOW PRESSUREgauge (11) is a 0 to 200 psig gauge and indicatesregulated low pressure.

4. The INPUT PRESSURE gauge (27) is a 0to 160 psig gauge and indicates regulated lowpressure.

5. The LOW RANGE ALTM (13) measureschamber altitude pressure and, under somecircumstances, suit simulator tank pressure. Itmeasures pressures equivalent to altitudes between10,000 and 40,000 feet.

6. The HIGH RANGE ALTM (12) measureschamber altitude pressure to indicate the altituderange equivalent to between 30,000 and 150,000feet.

NOTE: Each altimeter incorporates aninner scale, which indicates altitude in mmHg instead of in feet.

7. The PRESSURE/SUCTION manometer(4) has a range of –12.0 to +26.0 inches H20, andmeasures the amount of differential pressurebetween piezometer (26) and the altitude chamber,or between the piezometer and the suit simulatortank. It is used during component testing tomeasure safety pressure and pressure breathingpressures being delivered by the component andto measure suction flows being drawn through thecomponent.

8. The Hg manometer (5) has a range of 0 to12.0 inches Hg and measures, in inches Hg, theamount of differential pressure betweenpiezometer (26) and the altitude chamber, orbetween the piezometer and the suit simulatortank. It is used to measure resistance in an itemunder test.

NOTE: The rotameters used on the teststand are of the variable area type, whichmeans they get progressively larger towardthe top, allowing more nitrogen to passaround the ball. The point at which the ballstabilizes is known as the point of dynamicbalance. Readings are made across thecenter of the ball.

9. The OVERBOARD LEAKAGE rotame-ter (6) has a range of 20 to 200 CCM(1,000 CCM = 1 lpm) and is vented to ambient.It measures leakage, or bleed, from an item undertest. This rotameter is calibrated at 14.7 psig at70°F (ambient air).

10. The LOW RANGE LEAKAGE rotameter(7) has a range of 20 to 200 CCM, and is enclosedin the low-pressure system. It measures leakage,or bleed, from a component under test throughLEAKAGE CONTROL valve (E), or LEAKAGEON/OFF valve (G). This rotameter is calibratedwith nitrogen at 70 psig at 70°F.

11. The HIGH RANGE LEAKAGE ro-tameter (8) has a range of 200 to 2000 CCM. Itsfunction is the same as LOW RANGE LEAK-AGE rotameter (7). This rotameter is calibratedat 70 psig at 70°F.

12. The OUTPUT FLOW manometer (1) hasa range of 0 to 12.0 inches H20. It indicates theamount of output flow from the item under test.

13. The INPUT FLOW manometer (2) has arange of 0 to 12.0 inches H20. It indicates theamount of ambient air flowing into the altitudechamber.

14. The VENT FLOW manometer (L3) hasa range of 0 to 12.0 inches H20. It indicates theamount of supply pressure or ambient air to thesuit simulator tank.

TEST STAND CONNECTIONS

Several connections are incorporated in thetest stand (fig. 11- 1) for supplying and bleedingpressure to and from the system. These connec-tions are:

1. The N2 INPUT connector (15) is the N2

supply cylinder connection.

NOTE: The SYSTEM BLEED port (16)has been deleted on later configurations ofModel 1172AS100 test stands.

2. The SYSTEM BLEED port (16) bleedspressure from the various systems.

3. The N2 INPUT connection (18) is providedfor components that require inlet pressures. Eitherregulated high or regulated low pressures can beprovided to the connection. The N2 INPUT teeconnection (28), N2 INPUT PRESSURE gauge(27) and the gauge guard that protects the inputpressure gauge are connected to N2 INPUTconnection (18).

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CHECK VALVE CONNECTIONS

There are four connections located withinthe altitude chamber that have check valvesincorporated, and require insertion of a bayonet-type fitting to open the connection and route theflow (fig. 11-1). These connections are as follows:

1. The LOW PRESSURE connection (19)provides for a controlled flow of low-pressurenitrogen through LEAKAGE CONTROL valve(E) to the item under test.

2. The 20 to 200 CCM LEAKAGE connec-tion (20) connects the test item to OVERBOARDLEAKAGE rotameter (6), and is used whentesting components for leakage or bleed.

3. The REFERENCE TAP connection (21) isa reference tap to differential pressure indicatingmanometers (PRESSURE/SUCTION manometer(4) and Hg manometer (5)). It also has a referenceline that connects piezometer (26) intoREFERENCE TAP connection (21) downstreamfrom the check valve.

4. The HELMET REFERENCE TAP con-nection (24) is a reference tap connected to bothsuit simulator tank through SUIT SIMULATORREFERENCE SHUTOFF valve (R) or LOWRANGE ALTM (13) through REFERENCEPRESSURE SELECTOR valve (O).

NOTE: The CHAMBER REFERENCEport (N/N), also located within thechamber, references chamber pressure toALT CONTROLLER (B), PRESSURE/SUCTION manometer (4), Hg manometer(5), LOW RANGE ALTM (13), andHIGH RANGE ALTM (12).

Line traps, float check valves, and relief valvesare not shown in figure 11-1.

Line traps are incorporated in PRESSURE/SUCTION manometer (4) and Hg manometer (5)to trap liquids in case manometers are over-loaded.

The float check valves incorporated in theOUTPUT FLOW manometer (l), the INPUTFLOW manometer (2), the VENT FLOWmanometer (3) and the PRESSURE/SUCTIONmanometer (4) help to prevent a loss of liquid incase the manometers are overloaded.

The relief valves are incorporated in theREGULATED LOW PRESSURE gauge (11) andthe suit simulator tank. The relief valve onthe REGULATED LOW PRESSURE gauge(11) is preset at 200 to 230 psig and protectsthe gauge and rotameter system in case of gaugeguard failure. The PRIMARY relief valve ispreset at 15 psig and the SECONDARY reliefvalve is preset at 25 psig. These relief valvesprevent overpressurization of the suit simulatortank.

VACUUM PUMP

The VACUUM PUMP (VP) operates from a2 horsepower electric motor (fig. 11-3). The pumprotation is clockwise, when viewed from the rearof the test stand. The pump has the capability ofevacuating the chamber at a rate of 22.5 cubic feetper minute (cfm) at 81 mm Hg (51,600 feet)simulated altitude. It is used to evacuate thechamber or draw flow of air, nitrogen, or air andnitrogen from an item under test. The VACWM

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239.478Figure 11-3.—Vacuum pump.

PUMP vent (54) must be opened one to two turnswhen you operate the pump (fig. 11-1).

WARNING

ALWAYS ENSURE THAT THE PUMPMOTOR HAS A FOUR-PRONG ELEC-TRICAL CONNECTION PLUG. ONMODEL 1172AS100 ENSURE THATTHE GROUNDING LUG IS IN PLACEAND SECURELY CONNECTED. ASIDE VIEW OF THE VACUUM PUMPIS SHOWN IN FIGURE 11-3.

SAFETY PRECAUTIONS

Before you attempt to operate the test stand,review the following safety precautions. Thesesafety precautions must be observed before,during, and after test stand operation.

1. Ensure that the test stand is properlysecured prior to opening the supply cylinder valve.Position the HIGH PRESSURE REGULATORto LOAD, then to VENT, and ensure that theLOW PRESSURE REGULATOR is backed outand the other valves are turned fully to the right.

2. Keep the chamber door closed wheneverpossible.

3. Keep the test stand doors closed at alltimes.

4. Keep the test stand work tray closed whenit is not in use.

5. Check the pump lubricant prior to turn-ing the pump on (run for 2 minutes and checklubricant for proper level).

6. Keep your hands and head clear of beltsand pulleys while checking the lubricant level.

7. Ensure the test stand is properly groundedby using the grounding lug.

8. Never use regulated high pressure andregulated low pressure together.

9. When the oxygen monitor alarm sounds,leave the room.

10. Do not panic when the test standmalfunctions.

11. When you use nitrogen, ensure that theroom is well ventilated.

12. Use proper tools for the job you areperforming.

13. Do not inhale lubricant, oxygen cleaningcompound, or mercury fumes.

14. Wash pump lubricant or mercury fromhands immediately.

15. Secure the test stand completely after use.16. Never leave the test stand unattended

while the pump is running.17. When transporting the compressed nitro-

gen cylinder, you should ensure the protective capis on.

MAINTENANCE

Maintenance on the oxygen components teststand is discussed in the following paragraphs.

MANOMETER PREPARATION

Maintenance on the 1172AS100 begins as soonas the test stand is uncrated. You should fill theOUTPUT, INPUT, and VENT FLOW ma-nometers with a liquid that has a known specificgravity of 1.0. The liquid used for the 1172AS100is a mixture of one part concentrated greenmanometer fluid (merian D-2930) mixed with 10parts of water. To fill the manometers,your first step is to adjust the scale so that thezero is located half way between the full-up andthe full-down position.

Remove the fill plugs from the manometerreservoirs and fill the reservoir until the fluidreaches the zero mark on the scale. After you havefilled the reservoir to zero, replace the fill plugs.

To fill the pressure suction manometer withfluid, use red manometer fluid with a specificgravity of 1.9. The procedure is the same.Adjust the scale so the zero mark is half waybetween the full-up and full-down positions. Youhave one more type manometer to fill. The Hgmanometer uses triple-distilled mercury. To fillthis manometer, follow the same procedure thatyou used for the other manometers. Do not spillthe mercury. If you do, notify your supervisor,and follow the special precautions for cleaningmercury spills.

PRESSURE/LEAKAGE TESTS

To ensure maximum operating efficiency,pressure/leakage tests must be performedperiodically.

NOTE: Use systems schematic drawings asan aid in determining any malfunctionsthat may exist. You can find theseschematics in NAVAIR 13-1-6.4.

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Outward Leakage Test (Supply System)

The outward leakage test (fig. 11-1) isperformed as follows:

1. Ensure the supply cylinder valve and all teststand valves are closed.

2. Open fully, then close the supply cylindervalve.

3. Note the pressure registered on gauge (9).After 2 minutes, reread the pressure on gauge (9).There should be no pressure drop (a drop inpressure indicates leakage).

Outward Leakage Test(Regulated High-Pressure System)

The outward leakage test is performed asfollows:

1. Cap connection (18) in chamber.2. Open supply cylinder valve.3. Turn regulator (Q) to LOAD, and hold

until 2,000 psig (or cylinder pressure) is indicatedon gauge (10). The regulated low-pressure gaugeshould indicate the gauge guard cut-off pressure,170 ± 5 psig.)

4. Close the supply cylinder valve and notethe pressure on gauge (10). After 2 minutes, rereadgauge (10). There should be no pressure drop (adrop in pressure indicates leakage).

NOTE: If pressure is registered on gauge(27), a leak is indicated in ON/OFF valve(L) or ON/OFF valve (G). A pressure dropon gauge (11) also indicates valve (G) isleaking. Valve (G) will be independentlytested later.

Bleed pressure by turning (Q) to VENT. Openvalve (S) to bleed system, then close valve (S).

Outward Leakage Test(Regulated Low-Pressure System)

The outward leakage test is performed asfollows:

1. Open the supply cylinder valve. Turn theselector valve (F) to HIGH and the selector valve(D) to Hg.

2. Turn the ON/OFF valves (L) and (G) toON.

3. Slowly turn the regulator (N) clockwiseuntil 70 psig is indicated on gauges (1 1) and (27).

4. Return valve (L) to OFF and observerotameter (8). Any leakage will be indicated bythe ball rising in the rotameter tube. There shouldbe no leakage.

5. Turn valve (F) to LOW RANGE positionand observe rotameter (7). There should be noleakage.

6. Return valve (F) to HIGH RANGE, andvalve (L) to ON.

7. Slowly adjust the regulator (N) until 160psig is registered on gauge (11). Gauge (27) shouldindicate its gauge guard cut-off pressure of145 ± 5 psig.

8. Turn the ON/OFF valve (L) to OFF andobserve rotameter (8). There should be no leakageindicated.

9. Turn the selector valve (F) to LOWRANGE and observe rotameter (7). There shouldbe no leakage indicated.

10. Decrease the pressure to 70 psig by open-ing valve (S), and turning regulator (N) in acounterclockwise direction.

Leakage Control Valve (E) andLeakage ON/OFF Valve (G) Tests

Perform leakage control valve and leakageON/OFF valve tests as follows:

1. Connect a hose from connection (19) to tap(20) in the chamber, and observe rotameter (6).There should be no leakage indicated.

2. Turn the ON/OFF valve (G) to OFF andremove the cap from connection (18) in chamber.

3. Observe rotameter (7). There should be noleakage indicated.

Suit Simulator System Leakage Tests

Perform leakage tests on the suit simulatorsystem as follows:

1. Open the shutoff valve (R) and valve (J)fully. Place the selector valve (0) to the ALTCHAMBER, and valve (M) to the suit simulatorposition.

2. Remove the hose from tap (20) andconnect it to tap (21) (connecting connection (19)to tap (21)). Cap piezometer (26).

3. Place selector valve (D) in the H 2Oposition, and valve (F) in the HIGH RANGEposition.

11-11

4. Open valve (E) slowly to maintain apressure of 10.0 inches H2O throughout thesystem as indicated on manometer (4). Close valve(E). Any further climb on manometer (4) indicatesa leak through valve (H).

5. Open valve (E) to maintain 20.0 in. H2O.When pressure is constant, observe rotameter (8).There should be no leakage.

6. Turn valve (F) to LOW RANGE. Therotameter (7) should indicate no leakage.

7. Return valve (F) to HIGH RANGE, andclose valve (E). Remove the hose from connec-tion (19) and allow the pressure to escape fromthe hose.

NOTE: Open valve (C) to aid in relievingpressure; then close it.

8. When the pressure has equalized, connectthe hose from tap (21 ) to tap (20) in the chamber.Rotameter (6) should show no indication ofleakage.

9. Remove the cap from Piezometer (26),and disconnect the hose between taps (20) and (21)in the chamber.

10. Turn the regulator (N) counterclockwise,and open valve (S) to bleed system. Close all teststand valves with the exception of valves (R) and(J).

Altitude Chamber and Suit SimulatorTank Inward Leakage Test

Perform the altitude chamber and suitsimulator tank inward leakage test as follows:

1. Place valve (D) in the Hg position. Ensurethe ON/OFF valves (G) and (L) are in the OFFposition. Place valve (0) in the suit simulatorposition.

2. Close the chamber door and turn thevacuum pump motor ON.

3. Open the VACUUM CONTROL valve(B1) and “ascend” to 30,000 feet. Close (B1) andcheck to ensure that the same altitude is indicatedon both altimeters (12) and (13). At 30,000 feetyou will see the high-range altimeter start to climband at 40,000 feet the low-range altimeter will nolonger be in use. This happens automatically andthe low-range altimeter will not be damaged.

4. Using valve (B1) “ascend” to 40,000 feet;ensure that altimeters (12) and (13) register thesame altitude.

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5. Using the VACUUM CONTROL valve(B1), ascend to 52,000 feet. (Altitude is indicatedon altimeter (12).)

6. Close (B1); after a 2-minute stabilizationperiod, record the altitude indicated on altimeter(12). Altitude “loss” should not exceed 1000 feetin 20 minutes.

PERIODIC INSPECTIONS

Periodic inspections consist of daily, weekly,biweekly, and monthly inspections. Perform theseinspections at the prescribed intervals using theprocedures described in the following text.

Daily Inspection

Perform the daily inspection as follows:

1. Check the vacuum pump lubricant for theproper level (run the pump for 2 minutes andrecheck for proper level).

2. Inspect the gauges and manometers forcleanliness, fogged or broken glass, and zero ornormal indications.

3. Inspect the altitude chamber door forcleanliness, chips, scratches or cracks. Check thegaskets for excessive wear or deterioration.

4. Inspect the connections and adapters forcleanliness and distortion.

5. Check the identification plates forcleanliness, legibility, and security of attachments.

Weekly Inspection

The weekly inspection includes all the tasksof the daily inspection and the following addi-tional tasks:

1. Inspect the polyethylene tubing, fittings,connections, and rubber couplings for the correctfit, dirt or excessive dust, pin holes, radical bendsor kinks, surface abrasions and heat blisters.

2. Inspect the gauges, manometers, andflowmeters for the correct calibration decals,proper fluid level, and cleanliness of manometerand flowmeter tubes.

3. Perform the pressure leakage tests inaccordance with NAVAIR 13-1-6.4.

Biweekly Inspection

The biweekly inspection includes all thetasks of the weekly inspection and the followingadditional tasks:

1. Inspect the pump drive belt for propertension, pulley alignment, excessive belt wear, andtightness of pulley setscrews.

2. Perform the orifice calibration check inaccordance with AVAIR 13-1-6.4.

3. Perform the flowmeter intercomparisontest in accordance with NAVAIR 13-1-6.4.

Monthly Inspection

The monthly inspection includes all the tasksof the biweekly inspection and the following ad-ditional tasks:

1. Inspect the N2 and air inlet connectors fordirt, foreign matter, corrosion, stripped threads,and badly scared surfaces.

2. Inspect the gaskets at bulkhead fittings andvacuum pump filters for deterioration and properfits and alignments.

3. Inspect the copper tubing for corrosion andtightness of soldered joints.

4. Inspect the altitude chamber for clean-liness, proper fit and alignment of gaskets,excessive scratches on chamber door, leaks orcorrosion at pipe fittings, and wear of the doorgasket.

5. Inspect all tubing and piping for tightnessand proper alignment.

6. Inspect all electrical plugs, connectors, andwiring for physical damage, bent pins, looseconnections, and security of cables.

7. Inspect all control valves for cleanliness andtightness of mounting nuts and knobs.

VOL-O-FLO CALIBRATION

The intercomparison test compares the inputand output Vol-O-Flo elements to determine if theflowmeters need calibration. It is performed moreoften than the orifice calibration test as it isquicker and easier to perform.

The orifice calibration check accuratelydetermines whether the output Vol-O-Flo is withincalibration tolerances.

When a test stand fails the intercomparisontest, an orifice calibration check is performed.Failure of the intercomparison test and orifice

calibration check requires the removal and clean-ing of the input and output Vol-O-Flo elements.

NOTE: Prior to performing these calibra-tion checks, you should ensure that thereis no test stand leakage.

After cleaning, drying, and reinstallation ofthe Vol-O-Flo elements, both the intercomparisontest and the orifice calibration check must berepeated. Failure of the above tests after clean-ing will require the test stand be calibrated witha master calibrator, used by the metrology calibra-tion team.

VOL-O-FLO ELEMENT CLEANING

To clean the Vol-O-Flo element, proceed asfollows:

1. Disconnect the tubes from Vol-O-Flomanometers.

NOTE: Prior to removal of the element,mark the direction of the flow to ensureproper reinstallation.

2. Disconnect the element from the plumbingsystem by removing the hose and hose clamps atthe ends of the element.

3. Mix a cleaning solution of 4 percent liquiddetergent and water. (Mix 6 ounces of detergentwith 1 gallon of water.)

4. Flush the element in reverse from thedirection in which the air normally flows.

5. After the element has been well flushed, thedetergent is rinsed out immediately with cleanwater.

6. Install the element in the test stand,and create a flow through the element forapproximately 1 hour to ensure that it iscompletely dry.

7. After the element is dried, the test standis leak-tested.

8. Perform an intercomparison test andorifice calibration check in accordance with theNAVAIR 13-1-6.4.

LIQUID OXYGEN CONVERTERTEST STANDS

Liquid oxygen converters are another groupof items that you, as a PR, are required to testand repair. There are two test stands designed totest the oxygen converters. The operation,maintenance, and parts are, with a few minor

11-13

exceptions, basically identical. The part numbersfor the two test stands are 59A120, manufacturedby Aerojet-General Corporation, and the31TB1995-1, manufactured by Pioneer.

FUNCTIONS

The 59A120 test stand (fig. 11-4) is designedto test liquid oxygen converters, components, and

rigid seat survival kit (RSSK) components. Thisfunction is accomplished by the converter routinga test gas through various valves, gauges, andtubing to the item under test.

Bell Jar

The bell jar is used for testing componentshaving more than one possible area of leakage.

239.550Figure 11-4.—Liquid Oxygen Converter Test Stand 59A120 control panel and counter top.

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It consists of a relief valve RV-3, the bell jar itself,and the bell jar top coupling C-2 (fig. 11-4). Whenoperating properly, the relief valve RV-3 has arange of 5 to 15 psig. It is leaktight at 5 psi, andis set to relieve at 10 psi.

Differential Pressure Gauge, DF-1

The differential pressure gauge is a bellows-operated gauge that operates in the range of 0-100inches H2O (inches of water). The gauge indicatesdifferential pressure when testing pressure closingand opening valves.

Relief Valve, RV-11

The converter section of the test stand isprotected from excessive pressure by the RV-11relief valve. This relief valve is set to relievepressure in excess of 110 psig.

Converter Supply Connection, NIP-6

The converter supply connection NIP-6connects the converter supply coupling, throughthe use of a hose, to the test stand. The flow ofoxgen shown in figure 11-5 shows that the

239.551Figure 11-5.—Test stand schematic.

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converter supply flow control valve V-9 controlsthe flow of oxygen from the liquid oxygenconverter through the heat exchanger HE-1 to thebuildup and flow valve V-10, and then to theadapter fixture.

Linear Flow Elements

There are four linear flow elements. Eachmeasures a different flow rate in liters per minute(LPM). By using a hose assembly connected fromNIP-5 (converter supply outlet connection) to thecorrect one of the linear flow elements (NIP-1 for0-00.25 LPM, NIP-2 for 0-1.0 LPM, NIP-3 for0-50 LPM, or NIP-4 for 0-150 LPM), and turningthe flowmeter selector valve, you can measureleakage from an item under test.

Liquid Oxygen Quantity GaugeCapacitor-Type Tester

The liquid oxygen quantity gauge capacitor-type tester is located on the upper front panel ofthe test stand and operates on 115 Vat, 400-cyclecurrent. It is used to measure capacitance andelectrical insulation of the capacitance probe.

Flow of Oxygen

As you turn on the supply of gas, it flows intothe test stand through a special bulkhead fittingBF-1 (fig. 11-4), and it is indicated on the 0-3,000psig pressure gauge PG-3. It then flows to theadjustable pressure regulator R-1. The regulatoris preset to deliver 160 psig to the remainder ofthe test stand through oxygen supply valve V-6.Oxygen supply valve V-6, a needle-type valve,admits oxygen to the adapter fixture and controlsoxygen pressure to an item under test. From theadapter fixture, the test gas is routed to the follow-ing valves, gauges, and disconnects:

Test gas enters the bell jar bottom couplingC-1. Your test item is also attached to thiscoupling. From C-1 it flows to the needle meteringvalve V-2, which allows the flow to continue toa test pressure gauge PG-1.

NOTE: When opening valve V-2, you mustclose valve V-10. This prevents oxygenfrom entering the converter side of the teststand.

The test pressure gauge PG-1 indicates thepressure applied to the item under test. Theoxygen flow also goes from the adapter fixture

to the differential pressure gauge shutoff valveV-8. This valve prevents pressure from beingadmitted to the high side of the differentialpressure gauge DF-1 when the gauge is not beingused. Another flow from the adapter fixture isto the system bleed valve V-5. This valve is aneedle-type valve, and it is used to bleed thepressure from the test stand. On every test standyou will find a safety valve. In this case, we havea relief valve V-4 that prevents excessive pressurebuildup in the test stand. The valve is leaktightat 160 psig, and is set to relieve at 180 psig.

MAINTENANCE

Maintaining and preparing the test stand foruse is divided into five separate tasks: installation,visual inspection, correction card preparation,calibration, and leak testing. These tasks, fullydescribed in the following paragraphs, are out-lined briefly below:

1. Installation includes selecting a suitablespace, mounting, connecting to a suitable powersupply, and an oxygen source.

2. The visual inspection is performed toensure the test stand has not been damaged duringshipment and installation.

3. Correction/calibration cards (fig. 11-6)provide an easy reference upon which indicatedflows and pressures are recorded. Actualmandatory flows and pressures are taken fromNAVAIR 17-15BC-20 and are prerecorded on thecorrection/calibration cards. The actual LPMflow must be converted to the indicated inches ofH2O flow and to millimeter (mm) flow by usingthe applicable flowmeter calibration graphs. Thisconversion is performed by the metrology calibra-tion team.

NOTE: Additional actual pressures andflows have been added to the correctioncards in figure 11-6. Addition of thesepressures and flows reflect required actualpressures and flows needed to bench testRSSK kits and all models of LOXconverters now in service.

4. Periodic leakage tests are conducted on theaccessories section, bell jar assembly, and theentire test stand.

5. Calibration of the test stand is required tobe performed prior to use. Calibration proceduresare performed at 6-month intervals by the onsitemetrology calibration team. Additional calibra-tions are not required.

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Figure 11-6.—Calibration correction cards.

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Installation Table 11-1.—Test Stand Installation

The test stand may be installed in anyconvenient location. Table 11-1 includes nominaldimensions of the test stand. Total spacerequirements can be determined by adding areasonable working area to the dimensions givenin the table.

NOTE: The test stand has drilled flangesto allow stable mounting. If shock pads areplaced under the stand, they must extendunder the whole stand to give even distribu-tion of support.

Power requirement for the test stand is 115Vat, 400-cycle, single-phase service. The test standis connected to a suitable power source by theelectrical cable assembly.

A 300 to 2,000 psig oxygen source is required.A metal strap on the left rear of the test standis provided for mounting and securing the oxygensupply cylinder.

Visual Inspection

Visually inspect the test stand for thefollowing:

1. Dial glasses for cracks or breakage2. All hoses for cracks or breaks3. All pipe and hose fittings for security of

connection, worn, stripped or crossed threads4. All tubing for severe dents or punctures5. All valves for body cracks6. Heat exchanger for rupture, severe dents,

or punctures7. Gauge tester for damaged or loose parts,

and tightness of terminals and connectors

Any components found to be damaged ordefective should be repaired or replaced. Referto NAVAIR 17-15BC-20 for part numbers.

Test Stand Leakage Tests

Test stand leakage tests are performed bypersonnel attached to the oxygen shop andconsist of setting the oxygen pressure regulator,leak testing the accessories section, test standsection, and Bell Jar assembly.

SETTING THE OXYGEN PRESSUREREGUIATOR.— To set oxygen pressure regulator

11-18

R-1 to maintain 160 psig with 1,800 psig supplypressure applied, proceed as follows:

CAUTION

VALVES V-2, V-5, V-6, V-7, AND V-10ARE METERING (NEEDLE) VALVES.OVERTIGHTENING THESE VALVESWILL DAMAGE THE VALVE SEAT.ONLY FINGERTIGHT PRESSURESHOULD BE USED WHEN YOUCLOSE THESE VALVES.

1. Ensure that all test stand valves are closed,and plug the bell jar bottom coupling C-1.

WARNING

WHEN YOU WORK WITH OXYGEN,MAKE CERTAIN THAT CLOTHING,TUBING FITTINGS, AND EQUIP-MENT ARE FREE OF OIL, GREASE,FUEL, HYDRAULIC FLUID, OR ANYCOMBUSTIBLE MATERIALS. FIREOR EXPLOSION MAY RESULT WHENEVEN SLIGHT TRACES OF COM-BUSTIBLE MATERIAL COME INCONTACT WITH OXYGEN WHEN ITIS UNDER PRESSURE.

2. Open the oxygen supply cylinder valve.

NOTE: When you set regulator R-1, aMINIMUM of 1,800 psig of oxygenpressure is applied to the regulator.

3. Open the test pressure gauge to bell jarvalve V-2 slowly, and fully open the oxygen supplyvalve V-6.

4. Loosen the hex locknut located on the frontof regulator R-1. Turn the T-handle until 160 psigregisters on the test pressure gauge PG-1. Tightenthe hex locknut, and your oxygen pressure gaugeis now set.

5. Close the oxygen supply cylinder valve andopen the system bleed valve V-5 to bleed pressurefrom the system. After bleeding the pressure,remove the plug from the bell jar bottom couplingC-1.

L E A K A G E T E S T , A C C E S S O R I E SSECTION.— TO perform the leakage test on the

accessories section of the test stand, proceed asfollows:

1. Install the nipple assembly in the belljar bottom coupling C-1. Connect one end of thehose to the adapter, and the other end to thedifferential pressure connection NIP-7.

2. Ensure that the test pressure gauge to belljar valve V-2 is open. The system bleed valve V-5,the test pressure gauge buildup, and the vent valveV-10 and the differential pressure bleed valve V-7are closed.

3. Open the differential pressure shutoff valveV-8 and the oxygen supply cylinder valve.

4. Slowly open the oxygen supply valve V-6until 160 psig is indicated on test pressure gaugePG-1.

5. Now close the oxygen supply valve V-6.Leakage will be indicated by a drop in pressureon PG-1. Leakage should not be more than 2 psigin 10 minutes.

6. Leave all hoses and valves in their presentposition and start your test stand leakage test.

LEAKAGE TEST, TEST STAND.— T Operform the leakage test on the entire test standproceed as follows:

1. Open the converter supply flow controlvalve V-9 and test pressure gauge buildup and theflow valve V-10.

2. Plug the converter supply outlet NIP-5 andthe supply converter connection NIP-6. Ensurethat the system bleed valve (V-5) is closed.

3. Open the supply valve V-6 until the reliefvalve RV-11 unseats. (The relief valve is set torelieve at approximately 110 psig, and be leaktightat 100 psig.) Using the system bleed valve V-5,decrease pressure until 100 psig is indicated on testpressure gauge PG-1. Close valve V-6. Leakagewill be indicated by a drop in pressure on PG-1.Leakage should be no more than 10 psig in 10minutes.

4. Bleed the test standby opening the systembleed valve (V-5). Close all the test stand valves.Remove the plugs from the converter supply outletNIP-5 and the plug from the supply converterconnection (NIP-6).

BELL JAR ASSEMBLY LEAKAGETEST.— To perform a leakage test on the bell jarassembly, proceed as follows:

1. Remove the hose assembly and the nippleassembly from the bottom bell jar coupling C-1.Disconnect the opposite end of the hose fromdifferential pressure connection NIP-7.

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Table 11-2.-Troubleshooting Chart

11-20

2. Ensure that the differential pressure bleedvalve V-7, the test pressure gauge to bell jar V-2,and the system bleed valve V-5 are closed. Openthe differential pressure shutoff valve V-8.

3. Place the bell jar on the adapter fixture andsecure it with a clamp. Now plug the bell jar topcoupling C-2.

4. Open the oxygen supply valve V-6 slowlyuntil 100 inches of H2O is indicated on thedifferential pressure gauge DF-1. By closing valveV-6, leakage will be indicated by a drop inpressure on DF-1. There must not be more than2 inches of H2O in 10 minutes.

5. Close the oxygen supply cylinder valve andopen the system bleed valve V-5 to bleed thesystem.

6. Secure all test stand valves. Leave thesystem bleed valve V-5 open.

CAUTION

W H E N T H E T E S T S T A N D I SSECURED, ALL VALVES WITH THEEXCEPTION OF THE SYSTEM BLEEDVALVE V-5 MUST BE CLOSED.VALVE V-5 IS LEFT OPEN TO PRE-VENT THE ACCIDENTAL BUILDUPOF PRESSURE IN THE SYSTEM.

CLEANING

Clean all external parts, test adapters andconnections, gauge glasses, bell jar, O-ring, andterminals of the liquid oxygen quantity gaugecapacitor-type tester with a soft, lint-free cloth.The cloth may be dampened with oxygen clean-ing compound (MIL-C-81302).

PERIODIC INSPECTIONS

Periodic leakage inspections are required tobe performed weekly. A pressure regulator (R-1)setting must be performed weekly also. Inaddition to the inspection requirements, the teststand should be visually inspected for cleanliness,freedom from oil and grease, missing or damagedparts, and general condition.

TROUBLESHOOTING

Refer to table 11-2, Troubleshooting Chart,for probable trouble causes and remedies.Information in this chart is intended primarily toaid oxygen shop personnel in diagnosing problemsmost likely to be encountered in their daily useof the test stand. Refer to NAVAIR 17-15BC-20for parts removal and replacement.

Upon completion of any maintenance actions,complete the maintenance forms outlined in theNAVAIR 13-1-6.4.

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CHAPTER 12

Oxygencraft. They

OXYGEN-RELATED COMPONENTS

Learning Objective: Upon completion of this chapter, you will be able toidentify, maintain, and perform maintenance on oxygen regulators andliquid oxygen converters.

regulators are used in all naval air-supply the aircrew member with the

necessary oxygen to perform all flying dutiesunder all kinds of conditions. As a PR, you willmaintain, service, and test oxygen regulators andliquid oxygen converters. This chapter will giveyou a basic idea of how a miniature oxygenregulator functions, as well as a panel-mountedregulator and a liquid oxygen converter. It willalso cover some of the maintenance that you mustperform. The miniature regulator shown in figure12-1 is a model 29267-A1, type CRU-79/P, andthis model is manufactured by Bendix AviationCorporation. Other models are manufacturedby Clifton Precision, Robert Shaw ControlsCompany and ARO Corporation, but all are typeCRU-79/P. They are designed to regulate100-percent oxygen to the aircrew memberduring flight. Table 12-1 contains the leadingparticulars for the regulator.

The miniature regulator reduces and regulatessupply oxygen pressure to provide an adequateamount for breathing under a variety of condi-tions. It has a safety-pressure feature thatautomatically maintains a positive pressure in theaircrew members mask of 0.50 to 2.5 inches ofwater above the surrounding air pressure.(Inches of water is a means of measuring thecomparatively low pressure used in testing oxygenregulators.) This positive pressure is maintainedat all altitudes up to and including 34,000 feet.Above that altitude, the pressure-breathingfeature maintains a positive pressure in themask of up to 18.0 inches of water at altitudesbetween 34,000 and 50,000 feet, with the positivepressure increasing in proportion to the altitude.Miniature regulators can be used routinely up toapproximately 43,000 feet. However, due tohuman limitations, miniature regulators should

Figure 12-1.-Miniature oxygen breathing regulator model29267-A1.

Table 12-1.-Leading Particulars for Miniature OxygenBreathing-Regulator Type CR79/P

not be used above 43,000 feet except for very shortperiods.

Miniature regulators are designed for use withthe MBU-14 series oxygen mask as part of theoxygen system in all aircraft requiring 100-percentoxygen chest-mounted regulators. Refer to theNAVAIR 13-1-6.7 manual for personal configura-tions of the MBU-14 series oxygen mask.

12-1

MAINTENANCE

Maintenance of the type CRU-79/P regulatoris limited to inspection, testing, adjustment of thepressure breathing aneroid, and tightening ofloose screws. Ensure that antiseize tape is usedon pipe threads. This section contains only theprocedural steps necessary to meet theserequirements.

NOTE: Upon completion of anymaintenance action (for example, inspec-tion, adjustment, modifications, etc.), besure to complete the required maintenancedata collection system forms.

If the regulator fails any inspection or testingrequirements, it must be disposed of in accordancewith any local directives and replaced with a readyfor issue (RFI) component.

The miniature regulator will remain in serviceas long as it continues to function correctly anddoes not require other than authorizedadjustment.

Procedural steps outlined in this section arelisted under the inspection cycle in which they arerequired, and in the sequence in which theynormally occur.

DAILY/PREFLIGHT INSPECTION

The daily/preflight inspection is a visual typeinspection performed by the aircrew member towhom the regulator is issued, either daily or beforeeach flight. To perform this inspection, visuallyinspect the following:

WARNING

WHEN WORKING WITH OXYGEN,MAKE CERTAIN THAT CLOTHING,TUBING FITTINGS, AND EQUIP-MENT ARE FREE OF OIL, GREASE,FUEL, HYDRAULIC FLUID, OR ANYCOMBUSTIBLE MATERIALS. FIREOR EXPLOSION MAY RESULT WHENEVEN SLIGHT TRACES OF COM-BUSTIBLE MATERIAL COME INCONTACT WITH OXYGEN UNDERPRESSURE.

1. Inlet and outlet connections for security ofattachment. Make sure that all clamps, locknuts,fittings and screws are tight.

2. The regulator body for dents, scratches,corrosion, cracks, condition of the nameplate, orany other damage.

3. Perform a functional test as outlined in thenext inspection (special inspections).

If discrepancies are found or suspected, theregulator should be taken to the Aviator’s Equip-ment Branch for the required correctivemaintenance.

SPECIAL INSPECTIONS

Special inspections are required at specifiedintervals in addition to the daily/preflight orcalendar inspections. The interval for miniatureoxygen regulators is 30 days. This inspectionconsists of a visual inspection and a functionaltest, both performed by personnel of the Aviator’sEquipment Branch. To perform the specialinspection, proceed as follows:

1. Visually inspect the regulator as outlinedin the previous section (daily/preflight).

2. Functionally test the regulator by attachingthe mask, regulator, and delivery tube to a suitableoxygen supply source. Use a regulator-to-seat hosefor an attachment.

3. Turn on the supply source. There shouldbe a flow of oxygen through the mask.

4. Don the mask and breathe. There shouldbe a slight resistance on exhalation. This resistanceis due to the positive pressure feature of theregulator.

When you finish the special inspection, recordthe date and place of inspection in the’ ‘NOTES”section of the Aircrew Personal Protective Equip-ment History Card.

CALENDAR INSPECTION

The calendar inspection is performed on allminiature regulators upon issue prior to beinginstalled in an in-service personal oxygenconfiguration and must be performed on allminiature regulators in service at least every 90days.

The calendar inspection consists of a visualinspection and a bench test. All work must bedone in a clean, dust-free and oil-free area.

VISUAL INSPECTION

To visually inspect the miniature regulator,proceed as follows:

1. Disconnect the communication connectors.2. Loosen the hose clamp that holds the

regulator outlet to the mask delivery hose, andremove the regulator from the hose. Retain thehose clamp.

12-2

3. Loosen the locknut and remove theregulator-to-seat kit hose from the regulator inlet.

4. Inspect the regulator inlet and outlet forforeign objects, dirt, corrosion, dents, cracks, orother damage.

5. Inspect the regulator body for dents,cracks, corrosion, the condition of the nameplate,security of screws and fittings, and for otherobvious damage.

Miniature regulators that fail the visual

BENCH TEST

The bench test and all other tests mustbe performed using an Oxygen System Com-ponents Test Stand, Model 1172AS100. Referto chapter 11 of this training manual foridentification of test stand controls and in-dicators referred to in the bench test proceduresthat follow. Do not attempt to perform anybench test before becoming thoroughly familiarwith the test stand. Use a performance test

inspection or the bench test must be disposed of sheet when performing the “bench test. Seein accordance with any local directives. figure 12-2.

Figure 12-2.—Regulator Performance Test Sheet.

12-3

WARNING

BECAUSE OF POSSIBLE VACUUMPUMP EXPLOSION, ONLY WATER-PUMPED NITROGEN, TYPE 1, CLASS1, GRADE B, (FED. SPEC BB-N-411)WILL BE USED IN TESTING OXYGENREGULATORS. USE ONLY NITRO-GEN FROM GRAY CYLINDERSMARKED NITROGEN OIL FREE INWHITE LETTERS. TWO 3-INCH WIDEBLACK BANDS MARK THE TOPS OFTHESE CYLINDERS. OXYGEN TESTSTANDS CONTAIN A MERCURYMANOMETER. MERCURY IS ATOPIC METAL. AVOID BREATH-ING MERCURY VAPORS. AVOIDCONTACT WITH SKIN OR CLOTH-ING.

OVERLOAD TEST. To perform the overloadtest, proceed as follows:

1. Cap the regulator inlet and attach theregulator outlet to the short hose attached topiezometer (26) in the chamber. Ensure all teststand valves are in the secured position, then openthe N2 supply cylinder valve.

NOTE: Ensure the regulator outlet andpiezometer (26) are one inch apart.

2. Using the hose supplied with the test stand,connect LOW PRESS connection (19) to REF.TAP connection (21) in the chamber.

3. Ensure the FLOW SELECTOR valve (M)is in the REGULATOR position.

4. Adjust LOW PRESS. REGULATOR (N)so that regulated LOW PRESS. gauge (11)indicates 70 psig.

NOTE: When the in-system leakagerotameters are used, an inlet pressure of70 psig will normally be used, as this is thepressure used to calibrate the rotameters.

5. Place PRESS. SELECTOR valve (D) in theHg position.

6. Slowly open LEAKAGE CONTROL valve(E) until 1.85 inches in Hg is indicated on Hgmanometer (5). Maintain 1.85 inches of Hg for2 minutes. If no leakage is indicated on HIGHRANGE LEAKAGE rotameter (B), turn LEAK-AGE SELECTOR valve (F) to the LOW RANGEposition and check for leakage on the LOWRANGE LEAKAGE rotameter (7). The max-imum allowable leakage will be no more than theallowable leakage for each model shown on theperformance test sheet. If the leakage is excessive,

dispose of the regulator in accordance with yourlocal directives.

NOTE: A body leakage testis done on themodel 900-002-025-05 regulator only.Refer to the NAVAIR 13-1-6.4, DEMANDVALVE LEAKAGE TEST.

WARNING

NEVER BLOCK THE OUTLET OF THEMINIATURE REGULATOR WHILE APRESSURE IS APPLIED TO THEINLET. THIS WILL SERIOUSLYDAMAGE THE REGULATOR.

NOTE: If a high reading is encounteredduring this test, make sure the pressurebreathing aneroid is not screwed into theregulator housing too far before disposingof the regulator. Turn the pressure breath-ing aneroid counterclockwise out of theregulator housing and then recheck thereadings.

7. Disconnect the hose from LOW PRESSconnection (19) and REF TAP connection (21) inthe altitude chamber.

8. Uncap the regulator inlet and connect theregulator inlet to N2 input connection (18) in thealtitude chamber.

9. Ensure PRESS SELECTOR valve (D) isin the Hg position.

10. Turn on the vacuum pump.11. Turn INLET PRESS on/off valve (L) to

ON slowly.12. Using LOW PRESS REGULATOR (N),

apply 110 psig to the regulator inlet. The pressurewill be indicated on N2 INPUT PRESS gauge (27).

13. Open OUTPUT valve (C) to draw aflow through the regulator, then close valve(c ) .

14. Place PRESS SELECTOR valve (D) inH2O position. Observe the PRESS/SUCTIONmanometer (4) for 5 minutes. The pressure mustnot exceed 2.5 inches of H2O. After the 5 minuteperiod, read manometer (4) and enter the readingon the performance test stand. If the leakage isexcessive, dispose of the regulator.

15. Leave the positions of all controls andconnections unchanged.

SAFETY PRESSURE TEST. To perform thesafety pressure test, proceed as follows:

1. Adjust LOW PRESSURE REGULATOR(N) to 50 psig as indicated on N2 INPUT PRESSgauge (27).

12-4

CAUTION

OPEN FLUTTER DAMPENER VALVE(J) 1/4 TURN. IF THE REGULATORCAUSES THE FLUID IN PRESS/SUC-TION MANOMETER (4) TO FLUTTER,OPEN FLUTTER DAMPENER VALVE(J) SLOWLY UNTIL THE FLUTTER ISELIMINATED. IF AT ALTITUDEDESCEND TO SEA LEVEL PRIOR TOOPENING VALVE (J) AS THE PRESS/SUCTION MANOMETER CAN BEEASILY OVERLOOKED. WHENASCENDING TO ALTITUDE MAIN-TAIN AN OUTPUT FLOW OF 6.0INCHES OF H2O.

NOTE: When increasing flows the inletpressure must be adjusted to maintain thecorrect inlet pressure on N2 INPUTPRESS gauge (27).

2. With OUTPUT valve (C) closed, readPRESS/SUCTION manometer (4) and enterthe reading in the appropriate block on theperformance test sheet.

3. Adjust OUTPUT valve (C) to theequivalent of 100 lpm as indicated on the OUT-PUT manometer (1). Read the safety pressure asindicated on the PRESS/SUCTION manometer(4) and enter this figure on the performance testsheet. The safety pressure must not be less than0.50 nor greater than 2.5 inches in H2O for allflows.

4. Adjust low-pressure regulator (N) to 90 psigas indicated on the N2 INPUT PRESS gauge (27).

5. Repeat steps 2 and 3.6. Close the altitude chamber door.7. Ensure that REF PRESS SELECTOR

valve (O) is in the ALT. POSITION.

NOTE: A 6.0-inch flow in H2O must bedrawn with OUTPUT valve (C). OpenFLUTTER DAMPENER valve (J) 1/4turn.

8. If the altitude chamber is inadvertentlytaken above the test altitudes, open chamber bleedvalve (K) slowly and descend to the desiredaltitudes. Close valve (K).

9. Using VACUUM CONTROL valve (B),ascend to 34,000 feet as indicated on LOWRANGE ALTM. (13).

10. Repeat steps 1 through 5.

NOTE: If low safety pressure is en-countered, dispose of the regulator. If highsafety pressure is encountered at 34,000feet, before disposing of the regulatorensure that the pressure breathing has notcut-in before 35,000 feet giving a falseindication of high safety pressure.

11. Leave the position of all controls andconnections unchanged, and continue to thepressure breathing test.

PRESSURE BREATHING TEST. To per-form the pressure breathing test, proceed asfollows:

NOTE: If problems are encounteredduring this test, refer to pressure breathingtroubleshooting table 12-2 for adjustmentof the pressure breathing aneroid.

1. Open OUTPUT valve (C)and draw a flowof 6.0 inches in H2O through the regulator. UsingVACUUM CONTROL valve (B) ascend to 35,000feet as indicated on the LOW RANGE ALTM.(13).

Table 12-2.—Troubleshooting (Pressure Breathing Test)

12-5

2. Using LOW PRESS. REGULATOR (N),adjust the inlet pressure to 90 psig. Close OUT-PUT valve (C).

3. Read the PRESS/SUCTION manometer(4). The reading must be between 0.50 and 3.5in H2O. Enter this reading in the appropriateblock of the performance test sheet.

4. Adjust OUTPUT valve (C) to a flow of100 lpm and read the PRESS/SUCTIONmanometer (4). The reading must also be between0.50 and 3.5 in H2O. Enter this reading on thetest sheet also.

5. Increase the altitude to 43,000 feet, asshown on the HIGH RANGE ALTM. (12), andrepeat steps 1 through 3. The readings onPRESS/SUCTION manometer (4) must bebetween 9.2 and 12.5 in H2O.

6. Increase the altitude to 50,000 feet. Thereadings must be between 14.0 and 18.0 in H2Oat this altitude.

7. After the completion of this test, leaveOUTPUT valve (C) slightly open, and openCHAMBER BLEED valve (K) and return to sealevel.

8. Open the chamber door and close valve(C). Turn off the vacuum pump.

9. Turn ON/OFF valve (L) to OFF, andremove the regulator from the test stand.

10. Close the N2 supply cylinder and, usingLOW PRESS. REGULATOR (N) and SYSTEMBLEED valve (S), relieve all the pressure in thetest stand. Secure all the test stand valves.

11. If the aneroid should need adjusting,loosen the aneroid lockscrew using a .035 Allenwrench and adjust the aneroid assembly using re-taining pliers in accordance with the pressurebreathing test troubleshooting table 12-2.

NOTE: Remember we are discussing themodel 29267-A1 regulator only. For othermodels of the CRU-79/P miniatureregulator, you must refer to the NAVAIR13-1-6.4 manual.

After the completion of all the tests, you mustpurge the regulator with aviator’s breathingoxygen for 1 to 3 minutes at 90 psig to theregulator inlet.

WARNING

NEVER BLOCK THE OUTLET OF THEMINIATURE REGULATOR WHILEPRESSURE IS APPLIED TO THEINLET. THIS WILL SERIOUSLYDAMAGE THE REGULATOR.

After completion of the oxygen purge, place theregulator in a plastic bag for storage.

AIRCRAFT PANEL-MOUNTEDREGULATORS

The MD-1, CRU-52/A, CRU-54/A, CRU-55/A, CRU-57/A, MD2, and CRU-72/A shownin figures 12-3 and 12-4 are panel-mounted,automatic, positive pressure diluter demand-typeregulators, and they are used in conjunction withthe pressure breathing type oxygen mask. Theregulators provide 100-percent oxygen, or anair/oxygen mixture at the correct ratio, depending

Figure 12-3.—Aircraft panel mounted oxygen regulator,MD-1 (low pressure).

Figure 12-4.-Aircraft panel mounted oxygen regulator,MD-2 (high pressure).

12-6

on altitude, to the user on demand. The regulatorsincorporate an emergency pressure control lever.During normal operation, the lever is set in theNORMAL position. A TEST MASK position isprovided to test the oxygen supply function of theregulators at low altitudes and at ground level.When in the EMERGENCY position, theregulators deliver 100-percent oxygen to the userat a positive pressure. The EMERGENCYposition is used when normal oxygen is suspectedof being inadequate.

The regulators are supplied in two basicconfigurations: low pressure (50 to 500 psigoperating pressure range), and high pressure(50 to 2000 psig operating range). Referto table 12-3 for applicable models and partnumbers.

MAINTENANCE

When assigned to an AIMD or a depot-levelmaintenance activity, you may be involved inmaking repairs to these regulators. When the costof repair is more than approximately 75 percentof the cost of the regulator, it is considered beyondeconomical repair.

TURNAROUND/PREFLIGHT/POSTFLIGHT/TRANSFERINSPECTIONS

The turn around/preflight/postflight/transferinspections consist of a visual type inspectionperformed in conjunction with the aircraftinspection requirements for the aircraft in which

Table 12-3.-Leading Particulars

12-7

the regulators preinstalled. Refer to table 12-4for assistance in troubleshooting. To perform theinspection, visually inspect the following:

1. Electrical performance of panel light.2. Legibility of all markings.3. Plastic lighting plate for cracks and

discoloration.4. Low, or improper reading on regulator

pressure gauge.5. Emergency pressure control lever in

NORMAL position.6. Diluter control lever in 100-percent

OXYGEN position.7. Supply control lever in OFF position.8. Regulator and surrounding area for

freedom from dirt and hydrocarbons.9. Delivery hose and connector for cuts,

graying, kinking, hydrocarbons and generalcondition.

If discrepancies are found or suspected, notifymaintenance control.

If a regulator does not pass your inspectionand the defect cannot be repaired in the aircraft,remove it and put in a ready for issue (RFI)regulator. Forward the defective regulator to anaircraft intermediate maintenance activity that canfix it.

ACCEPTANCE/SPECIAL/DAILYINSPECTIONS

The acceptance/special/daily inspectionsconsist of a visual inspection followed bya functional test. These inspections and testsare performed in conjunction with the air-craft inspection requirements for the aircraftin which the regulators are installed. Theseinspections are performed at the organizationallevel by AMEs. However, you should knowwhat they are supposed to inspect. Refer totable 12-4 for assistance in troubleshooting.To perform the inspection, visually inspectthe regulators as you did in the preflightinspection.

Table 12-4.-Troublesbooting (Daily, Preflight, Special, Turnaround, Transfer and Acceptance Inspections)

12-8

To perform the functional test proceed asfollows:

1. Place the supply valve control lever in theON position.

2. Place the diluter control lever in NORMALOXYGEN position.

3. Using an oxygen mask and hose assembly,connect the hose to the quick disconnect. Whileat ground level, the regulator will not supplyoxygen from the supply system to the mask. Theemergency pressure control lever must be used inorder to check out the oxygen supply function ofthe regulator at low altitudes. (The emergencylever is spring loaded at the NORMAL position,and will return to NORMAL when released.)Place the mask to your face with the regulatorin test mask position and inhale. Proper regulatoroperation will be indicated by the flow indicatorassembly showing white during inhalation andblack during exhalation.

4. Hold the emergency pressure control leverin the TEST MASK position and observe the flowindicator. The flow indicator should be white,indicating a flow through the regulator.

Upon completion of the functional test, securethe regulator as follows:

1. Disconnect the mask from the supply hose.2. Ensure that the emergency pressure

control lever returns to its NORMAL position.3. Place the diluter control lever in the

100-percent position.4. Place the supply valve control lever in the

OFF position.

If any discrepancies are found or suspected,notify maintenance control. If repairs cannot bemade in the aircraft, replace the regulator andforward the defective regulator to AIMD forrepairs.

CALENDAR/PHASED/SDLMINSPECTIONS

You must remove the regulator to give it acalendar, phased or SDLM (standard depot-levelmaintenance) inspection. See applicable PlannedMaintenance System (PMS) publications forspecified intervals. In no case can the intervalexceed 231 days. Upon removing it from the air-craft, the regulators are visually inspected and sentto AIMD for bench testing.

Aircraft panel-mounted regulators that fail thebench test must be repaired. Source, Maintenanceand Recoverability (SM&R) codes define repair-ability of components and lowest level ofmaintenance authorized.

Service Life

Oxygen regulators remain in service for as longas they function correctly and do not requireexcessive repair (exceeds 75-percent of originalcost of regulator). All silicone rubber parts arereplaced whenever a regulator is disassembled forrepair.

Bench Test

Bench tests are performed on aircraft panel-mounted oxygen regulators prior to being placedin service, and during the phase/calendar orSDLM inspection cycle of the aircraft in whichinstalled. See applicable PMS publications forspecific intervals. The inspection interval must notexceed 231 days. The regulators are also subjectedto a bench test if malfunction is suspected, andafter repair or replacement of damaged parts.

Bench tests are performed using Oxygen Sys-tem Components Test Stand, Model 1172AS100,in accordance with NAVAIR 13-1-6.4. Becauseof the complexity of the 1172AS100 test stand,it is essential that the operator become thoroughlyfamiliar with the test stand prior to performingbench tests.

NOTE: Nitrogen supply cylinders used intesting oxygen components are 80 cubicfeet and contain a maximum pressure of2000 ± 200 psig. For tests requiringpressures of 1800 psig, use highest availablepressure, but in no case can this pressurebe less than 500 psig.

Inward Leakage Test

By applying 9.0 inches (H2O) of suction to theregulator outlet, you are testing the regulator tobe leaktight. If a leak is present, it could effectother tests covered in the chapter. It could alsoprevent the aircrewman from receiving 100-percentoxygen by allowing ambient air to enter theregulator.

To perform the inward leakage test, proceedas follows:

1. Ensure that all test stand valves are closed,then open N2 supply cylinder valve.

12-9

2. Place the regulator supply control valvelever in the OFF position, and the diluter controllever in the 100-percent OXYGEN position.

3. Ensure that the regulator emergencypressure control lever is in the NORMALposition.

4. Mount the adapter supplied with the teststand (NAVAIR Drawing No. 1172AS136), andconnect the regulator outlet to the N2 INPUTconnection in the altitude chamber.

5. Connect a line from the LOW PRESSconnection to REFERENCE TAP in the altitudechamber. Plug the rubber hose attached to thepiezometer by using the piezometer plug suppliedwith the test stand. Ensure that the LOWPRESSURE REGULATOR is not loaded. Thiswill prevent N2 supply cylinder pressure frompassing onto the INLET PRESSURE ON/OFFvalve which could damage the test item or injurethe test stand operator.

6. Turn the INLET PRESSURE ON/OFFvalve to the ON position. The vacuum vent mustbe opened one to two turns when you operate thevacuum pump. Turn the vacuum pump on.

7. Turn the PRESSURE SELECTOR valveto the H2O position, and fully open theLEAKAGE CONTROL valve.

8. Ensure that the LEAKAGE SELECTORvalve is in the HIGH RANGE position.

9. The leakage rotameter is calibrated withan applied pressure of 70 psig. The inward leakagetest requires that a suction of 9.0 in H2O beapplied to the regulator outlet and the rotameter.This pressure difference (9.0 in H2O vice 70 psig)creates a wide variance between actual leakage andindicated leakage. The maximum allowableleakage for the inward leakage test is 200 cubiccentimeters per minute, and is displayed as 740ccm on the high range leakage rotameter.

NOTE: Because of labeling on gauges, theabbreviation ccm is used in this text. Sincethe cubic centimeter has been replaced bythe milliliter, this abbreviation should beml/min instead of ccm. The properabbreviation may appear on later equip-ment and newer technical manuals.

Slowly open the OUTPUT valve until 9 incheso f H2O s u c t i o n i s i n d i c a t e d o n t h ePRESSURE/SUCTION manometer. Any leakagewill be displayed on the HIGH RANGELEAKAGE rotameter. The maximum allowableindicated leakage reading is 740 ccm (actual 200ccm). Record the indicated leakage on thePerformance Test Sheet.

10. Close the OUTPUT valve and theLEAKAGE CONTROL valve. Turn the vacuumpump OFF. Turn the INLET PRESSUREON/OFF valve to the OFF position.

Table 12-5A.—Troubleshooting (Inward Leakage Test)

12-10

11. Disconnect the line from the LOWPRESSURE connection and REF. TAP in thealtitude chamber. Disconnect the regulator outletfrom N2 INPUT connection, and remove the plugfrom the piezometer.

12. If excessive leakage is indicated, locate theprobable cause by using troubleshooting chart,table 12-5A.

Outlet Leakage Test

To perform an outlet leakage test, proceed asfollows:

1. Place the regulator supply valve controllever in the ON position.

2. Ensure that the diluter control lever is inthe 100-percent OXYGEN position.

3. Place the emergency pressure control leverin the NORMAL position.

4. Mount the regulator on a horizontal planein the test chamber. Connect the regulator inletto the N2 INPUT connection (18) inside thealtitude chamber.

5. By using the LOW PRESSURE REG-ULATOR, apply 150 psig to the regulator inlet.

6. Slowly turn the INLET PRESSUREON/OFF valve to ON.

7. Activate the emergency pressure controllever to allow a flow through the regulator, thenreturn the lever to its NORMAL position.

8. Draw a film of leak detection compound(MIL-L-25567) across the regulator outlet. Thefilm should not advance more than 1/2 inch in10 seconds. If the film advance is more thanallowable, repeat the test three or four times.(Distention could be caused by difference intemperature between inside and outside ofregulator.)

9. If the film advance continues to be morethan allowed, locate the probable cause by usingthe troubleshooting chart, table 12-5B.

10. Relieve pressure on the regulator by back-ing out on the LOW PRESSURE REGULATOR.

OXYGEN SUPPLY VALVE LEAKAGETEST.— If the supply pressure could not be shutoff, until a demand was placed on it, a pressurebuildup could be created. It could damage theregulator hose or mask and possibly injure thecrewmen. To perform the oxygen supply valveleakage test with the regulator still mounted in thechamber, proceed as follows:

1. Place the regulator oxygen supply valvelever in the OFF position.

Table 12-5B.—Troubleshooting (Outlet Leakage Test)

12-11

2. Place the emergency pressure control leverin the EMERGENCY position.

3. Using HIGH PRESSURE REGULATOR,apply pressure specified in table 12-6 to theregulator inlet. Slowly turn the INLETPRESSURE ON/OFF valve to ON.

4. Draw a film of leak detection compound(MIL-L-25567) across the regulator outlet fitting.As in the last test, see if there is any distentionof the film.

5. There is no allowable leakage. If leakageis noted , l ocate probable cause us ingtroubleshooting chart, table 12-7.

6. Place the emergency control lever in theNORMAL position.

OVERALL LEAKAGE TEST.— Test, bytrapping pressure in the regulator, for any leakageanywhere on or in the regulator. Perform theoverall leakage test first with diluter lever in its100-percent OXYGEN position, and then repeatit with the lever in the NORMAL OXYGENposition.

1. Place regulator oxygen supply valve leverin the ON position, and emergency pressurecontrol lever in the NORMAL position.

2. By using test stand HIGH PRESSUREREGULATOR, apply pressure specified in table12-8 to regulator inlet.

3. Turn INLET PRESSURE ON/OFF valveto OFF. Leave the regulator oxygen supply valvelever in the ON position.

4. Leakage will be indicated on the regulatorpressure gauge. Allowable leakage should notexceed 60 psig over a 2-minute period. Repeat thetest with the diluter lever turned to NORMALOXYGEN.

Table 12-6.—Inlet Pressure (Oxygen Supply Valve LeakageTest)

12-12

5. If allowable leakage is exceeded, locate theprobable cause by using the troubleshooting chart,table 12-9.

6. Turn the HIGH PRESSURE REGULA-TOR to VENT.

7. Bleed the regulator by placing the emer-gency pressure control lever in the EMERGENCYposition. Return the lever to NORMAL.

8. Bleed the test stand using the SYSTEMBLEED valve.

REGUI.ATOR PRESSURE GAUGE SCALEAND ERROR TEST.— This test ensures that thepressure gauge is operating properly and withintolerance. To perform the regulator pressuregauge scale and error test, proceed as follows:

1. Turn the INLET PRESSURE ON/OFFvalve to ON. The LOW PRESSURE REGULA-TOR can only be used when applying pressuresbelow the gauge guard setting (165 to 175 psig)to an item under test. For pressures above thegauge guard setting, the HIGH PRESSUREREGULATOR must be used.

2. Using LOW PRESSURE REGULATOR(N), slowly increase the pressure to each testpressure in 100 psig increments and below, asspecified in table 12-6. Record the regulatorpressure gauge readings twice, once before andonce after tapping regulator pressure gauge.

3. Check the tolerance by comparing theregulator pressure gauge reading with the teststand INPUT PRESSURE gauge.

4. Back out on the LOW PRESSUREREGULATOR.

5. Continue the test for 500 psig pressure byusing the HIGH PRESSURE REGULATOR.

6. Turn the HIGH PRESSURE REGULA-TOR to VENT.

7. Bleed the test standby using the SYSTEMBLEED valve. Bleed the regulator using theemergency pressure control lever.

OUTWARD LEAKAGE TEST.— In per-forming this test, the relief valve is not covered.The allowable leakage through this valve at 17.0inches H2O is included in the maximum allowableleakage of 120 ccm.

NOTE: This text uses the abbreviationslpm for liters per minute. Newer equipmentand technical manuals may use the correctabbreviation, which is L/min.

Table 12-7.-Troubleshooting (Oxygen Supply Valve Leakage Test)

Table 12-8.-Inlet Pressure (Overall Leakage Test) With the regulator still mounted in thechamber, proceed as follows:

1. Place the regulator supply valve controllever in the OFF position, and the diluter controllever in the NORMAL OXYGEN position.

2. Connect the regulator outlet to thepiezometer in the altitude chamber.

3. Connect a line from the LOW PRESSUREconnection to the REFERENCE TAP inside thechamber.

4. Turn the test stand INLET PRESSUREON/OFF valve to the OFF position.

Table 12-9.-Troubleshooting (Overall Leakage Test)

12-13

5. Adjust the LOW PRESSURE REGULA-TOR until 70 psig is indicated on theREGULATED LOW PRESSURE gauge.

6. Turn the PRESSURE SELECTOR valveto the H2O position, and slowly open theLEAKAGE CONTROL valve until 17.0 inchesof H2O is indicated on PRESSURE/SUCTIONmanometer. By adjusting the LEAKAGE CON-TROL, you maintain 17.0 inches of H2O indica-tion throughout this test.

7. If no leakage is indicated on the HIGHRANGE LEAKAGE rotameter, turn the LEAK-AGE SELECTOR valve to the low range posi-tion, and check for an indication of leakage onthe low RANGE LEAKAGE rotameter.Allowable leakage is 0.12 lpm (120 ccm).

8. Switch the LEAKAGE SELECTOR valveto HIGH position, and close the LEAKAGECONTROL valve.

9. Repeat steps 6, 7, and 8 with the dilutercontrol lever in the 100-percent OXYGENposition.

10. If leakage is excessive, locate its probablecause using troubleshooting chart, table 12-10.

SECOND STAGE RELIEF VALVE TEST.—To perform the second stage relief valve test,proceed as follows:

1. Turn the PRESSURE SELECTOR valveto the Hg position, and place the FLOWSELECTOR valve in the CONTROLLERposition.

2. Ensure the diluter control lever is in the100-percent OXYGEN position.

3. Using the VENT PRESSURE valve, slowlyapply 3 inches of mercury to the regulator outlet.The regulator relief valve should be venting atleast 45 lpm, as indicated on the vent flowmanometer.

4. Close the VENT PRESSURE valve andbleed the pressure down to 0 in Hq using VENTAMBIENT valve. Close the valve.

Table 12-10.—Troubleshooting (Outward Leakage Test)

12-14

5. Turn the FLOW SELECTOR valve to theREGULATOR position and close the VENTAMBIENT valve.

6. Slowly move the PRESSURE SELEC-TOR valve to the H2O position.

7. Turn the LEAKAGE SELECTOR valveto the LOW position.

8. Open the LEAKAGE CONTROL valve.Apply and maintain 17.0 inches of H2O toregulator outlet. Maximum allowable leakage is0.12 lpm (120 ccm).

9. Close the LEAKAGE CONTROL valve.10. Back out on the LOW PRESSURE

REGULATOR and bleed the pressure with theSYSTEM BLEED valve.

11. Turn the LEAKAGE SELECTOR valveto the HIGH RANGE position.

12. If excessive leakage is found, locate theprobable cause using the troubleshooting chart,table 12-10. If the relief valve does not vent, locatethe probable cause by using the troubleshootingchart, table 12-11.

FLOW SUCTION TEST.— This test deter-mines how much suction will be required by theuser to achieve or receive a given amount ofoxygen or air/oxygen mixture through theregulator. To perform the flow suction test,proceed as follows:

1. Disconnect the hose from the LOWPRESSURE connection and REFERENCE TAPconnection inside the altitude chamber.

2. Turn vacuum pump ON.3. Ensure that the PRESSURE SELECTOR

Valve is in the H2O position.

4. Ensure that the regulator diluter controllever is in the 100-percent OXYGEN position.

5. Ensure that the INLET PRESSUREON/OFF valve is ON.

6. Ensure that the regulator supply valvecontrol lever is in the ON position.

7. By using the LOW PRESSURE REGU-LATOR, set the inlet pressure at each inlet pres-sure specified on the Performance Test Sheet.

8. By using the OUTPUT valve, set flowsspecified in the Performance Test Sheet onthe OUTPUT manometer. Readings must berecorded with the regulator diluter control leverin both NORMAL and 100-percent OXYGENpositions for each outlet flow specified on thePerformance Test Sheet. Suction values will bedisplayed on PRESSURE/SUCTION manome-ter. With no suction on the regulator (OUTPUTvalve closed), maximum flow through regulatorshould not exceed 0.01 lpm. This will cause aslight rise in the PRESSURE/SUCTION ma-nometer reading. Record readings on thePerformance Test Sheet.

9. Close OUTPUT valve.10. If the regulator fails the flow suction test,

locate the probable cause by using thetroubleshooting chart in table 12-12.

Table 12-11.—Troubleshootig (Second Stage Relief Valve Test)

Table 12-12.—Troubleshooting (Flow Suction Test)

12-15

OXYGEN RATIO TEST.— This test deter-mines the amount of oxygen mixed with ambientair up to 32,000 feet where 100-percent oxygenwill be automatically delivered to the user. Toperform the oxygen ratio rest, proceed as follows:

1. Ensure that the regulator supply valvecontrol lever is in the ON position, and the dilutercontrol lever is in the NORMAL OXYGENposition.

2. By using the LOW PRESSURE REGULA-TOR, apply 150 psig to the regulator inlet. Slowlyopen the VACUUM CONTROL valve (B1) andobserve the PRESSURE/SUCTION manometer.If a rapid increase in pressure is indicated, closedown on VACUUM CONTROL valve (B1) untilpressure stabilizes. This rapid increase of pressureshown on PRESSURE/SUCTION manometer iscaused by too fast a rate of climb in the altitudechamber. Maintain 3.0 inches of H2O on theOUTPUT manometer with OUTPUT valve while“ascending to altitude.”

3. Using VACUUM CONTROL valve (B1),ascend to the first test altitude shown on thePerformance Test Sheet.

4. Set the output flows specified in thePerformance Test Sheet with OUTPUT valve, andstabilize altitude with INPUT valve.

5. Read all readings on the INPUT manome-ter, and record all readings on the PerformanceTest Sheet.

6. Continue the test for each specified altitudeand output flow shown on the Performance TestSheet.

7. Close OUTPUT valve and INPUT valve.Descend to 27,000 feet using CHAMBER BLEEDvalve.

8. If oxygen ratio test was satisfactory,proceed to make the safety pressure and pressurebreathing test. If indicated input flows are notwithin limits, an aneroid closure test must beperformed. The aneroid closure test is performedonly if regulator fails the oxygen ratio test.

ANEROID CLOSURE TEST.— The aneroidclosure test is preformed only if the regulator failsthe oxygen ratio test. To perform the aneroidclosure test, proceed as follows:

1. Descend to 25,000 feet by using theCHAMBER BLEED valve.

2. Ensure that the inlet pressure is as specifiedon the Performance Test Sheet.

3. Setup a flow of 5.0 inches of H2O on theOUTPUT FLOW manometer with OUTPUTvalve.

4. The aneroid closes between 28,000 and32,000 feet, as indicated by no further advancein altitude on the LOW RANGE altimeter.

5. Close the OUTPUT valve and descend tosea level by using the CHAMBER BLEED valve.

6. If the regulator fails aneroid closure testand/or oxygen ratio test, locate probable causeusing troubleshooting chart, table 12-13.

SAFETY PRESSURE AND PRESSUREBREATHING TEST.— This test determines if100-percent oxygen is being delivered to the userthrough the regulator between 30 and 50,000 feet.

Table 12-13.—Troubleshooting (Oxygen Ratio/Aneroid Closure Tests)

12-16

To perform the safety pressure and pressurebreathing test, proceed as follows:

1. By using the LOW PRESSURE REGULA-TOR, apply 150 psig to the regulator inlet. Ifchamber altitude is not at 30,000 feet, adjust thealtitude by using VACUUM CONTROL valve(B1) to increase or CHAMBER BLEED valve todecrease altitude.

2. Using the OUTPUT valve, draw flows of0, 40, and 85 lpm through the regulator. Deliverypressure must be within limits shown on RegulatorPerformance Test Sheet. Maintain 3.0 inches ofH2O on output manometer with OUTPUT valvewhile ascending to altitude. The reading for 0 lpmmust also be recorded at each test altitude.

3. Repeat step 2 for each altitude shown onthe Performance Test Sheet.

4. Close the OUTPUT valve and descend tosea level by using CHAMBER BLEED valve.

5. If the safety pressure breathing flows arenot within limits, locate the probable causeusing troubleshooting chart, table 12-14.

BLINKER ASSEMBLY TEST.— This testensures that the blinker operates correctly witha demand placed on the regulator. To performthe blinker assembly test, proceed as follows:

1. Ensure that diluter control lever is in theNORMAL OXYGEN position.

2. By using the LOW PRESSURE REGULA-TOR, apply 150 psig to the regulator inlet.

3. Using OUTPUT valve draw a 20 lpmthrough the regulator. The blinker must openfully.

4. Reduce output flow to 8 lpm and placethe diluter control lever in the 100-percentOXYGEN position. The blinker must remain fullyopen.

5. Close OUTPUT valve. The blinker shouldclose immediately.

6. Close the altitude chamber door. Ascendto altitude while maintaining 3.0 inches of H2Oon the OUTPUT manometer with the OUTPUTvalve.

7. By using the VACUUM CONTROL valve(B1) ascend in altitude until 17.0 inches of H2Ois indicated on the PRESSURE/SUCTIONmanometer.

8. Open OUTPUT valve and draw a flow of12 lpm through the regulator. The blinker shouldbe fully open. Close OUTPUT valve and theblinker should close immediately.

9. Descend to sea level using the CHAMBERBLEED valve.

10. Adjust or replace improperly functioningblinkers.

EMERGENCY PRESSURE TEST.— Deter-rnine how much pressure is supplied to the useron emergency pressure. To perform the emergencypressure test, proceed as follows:

1. Ensure the diluter control lever is in theNORMAL OXYGEN position.

2. By using the LOW PRESSURE REGULA-TOR, apply 150 psig to the inlet of the regulator.

3. Open the OUTPUT valve and draw a 10lpm flow through the regulator.

Table 12-14.—Troubleshooting (Safety Pressure/Pressure Breathing Test)

12-17

4. Place the emergency control lever in theEMERGENCY position. Pressure indicated onPRESSURE/SUCTION manometer should read2.0 to 4.0 inches of H2O .

5. Adjust the OUTPUT valve to draw 80lpm through the regulator.

6. Place the diluter control lever in the100-percent OXYGEN position. Pressure at outletof regulator, as indicated on PRESSURE/SUCTION manometer, should be no less than 1.0inches of H2O.

7. Close the OUTPUT valve. With zeroflow, outlet pressure should not exceed 5.5 inchesof H2O .

8. Adjust the output to 10 lpm. Hold theemergency pressure control lever in TEST MASKposition. The output flow indicated on thePRESSURE/SUCTION manometer should be6.0 to 16.0 inches of H2O.

9. Close the OUTPUT valve. With zero flow,outlet pressure should not exceed 17.5 inches ofH2O. Release the emergency pressure controllever. If the regulator fails, adjust the emergencypressure control lever stem to obtain 3.0 to 4.0inches of H2O at 10 lpm first, then compensatefor excessive pressure drop at 80 lpm flow withthe elastic stop nut.

10. If the emergency pressure flows are notwithin tolerance, locate the probable cause byusing the troubleshooting chart, table 12-15.

11. Close the N2 supply cylinder valve, byusing the LOW PRESSURE REGULATOR andSYSTEM BLEED valve, relieve all pressure in thetest stand. Secure all test stand valves.

12. Test stand operator and CDI must signthe Performance Test Sheet. The original, or a

copy of the Performance Test Sheet is forwardedto the operational custodian of the regulator.

LIQUID OXYGEN CONVERTERS

The liquid oxygen converter assembly dis-cussed in this chapter is a GCU-24/A, P/N10C-0016-10 (fig. 12-5) manufactured by EssexCryogenics, Inc. (FSCM 19062). Informationconcerning other types can be found in NAVAIR13-1-6.4. The converter assembly is designed tostore and convert liquid oxygen (LOX) intogaseous oxygen for the aircrewman during flight.Table 12-16 contains the leading particulars forthe converter assembly.

Oxygen in its liquid state (approximately–297 °F or –182 °C) is stored in a sphericalassembly consisting of inner and outer shellsseparated by an annular space. The annular spaceis evacuated to create a vacuum. This prevents thetransmittal of heat through the annular space. Thethermos bottle effect created retards heating andeventual conversion of LOX to gaseous oxygen.Valves, tubing, and fittings incorporated in theconverter assembly convert LOX to gas and directits flow at a controlled rate.

CONFIGURATION AND FUNCTION

The type GCU-24/A Liquid Oxygen Con-verter Assembly (P/N 10C-0016-10) consists ofa sphere assembly, buildup and vent valve, reliefvalve, pressure closing valve and associatedtubing and fittings. A capacitance-type probeassembly, which sends an electrical signal to a

Table 12-15.—Troubleshooting (Emergency Pressure Test)

12-18

Table 12-16.—Leading Particulars for Liquid Oxygen Con-verter Assembly, Type GCU-24/A, P/N 10C-0016-10

Figure 12-5.—Liquid oxygenGCU-24/A, P/N

converter assembly, type1OC-OO16-1O.

liquid oxygen quantity gauge located in the air-craft, is incorporated within the sphere assembly.The quantity gauge indicates the amount of LOX,in liters, contained in the converter.

Operation and performance characteristics ofthe GCU-24/A converter assembly (P/N10C-0016-10) are as follows:

1. The converter is filled by attaching theLOX servicing trailer filler valve to the filler portof the fill, buildup, and vent valve on theconverter. When attached, the servicing trailerfiller valve depresses the nosepiece and valvepoppet of the fill, buildup, and vent valve. Thisautomatically puts the converter into the fill mode(fig. 12-6). Figure 12-7 shows the converterinstalled in an aircraft.

2. With the poppet depressed, the fill and ventports of the valve are opened, and the buildupport is closed. This condition allows gas pressurebuilt up in the inner sphere to vent to theatmosphere. As pressure is vented, LOX in theservicing trailer (which is at a greater pressure-30psig), flows through the fill, buildup, and ventvalve and into the converter.

3. As the LOX level rises in the sphere,pressure created by vaporization of liquid due toheat, turbulence, etc., is vented to the atmosphere.The converter is considered full when LOX flowsin a steady stream from the overboard vent linequick disconnect.

4. When the converter is full and the servicingtrailer filler valve is disconnected, the nosepieceand poppet of the fill, buildup and vent valvereturn to the extended position (fig. 12-6). Thisautomatically puts the converter into the buildupand supply mode by closing the fill and vent portsof the vaIve, and opening the buildup port.

5. In the buildup and supply mode (fig. 12-6),LOX is forced out of the bottom of the innersphere and into the buildup coil by the weight ofthe liquid. As the LOX warms and vaporizesinto gaseous oxygen in the buildup coil, pressureis created. This pressure is controlled atapproximately 75 psig by the opening and closingaction of the pressure closing valve.

6. Gaseous oxygen travels from the buildupcoil through the supply quick disconnect and theheat exchanger to a shut-off valve in the aircraftcockpit.

7. Gaseous oxygen, under pressure, alsopasses through the gas and buildup ports of thefill, buildup and vent valve to the upper portionof the pressure closing valve, within which is abellows. This bellows holds the valve in the openposition. As pressure builds, the bellows, whichsenses the increase, contracts (at approximately75 psig), and closes the valve.

8. Without a demand being placed on theconverter, pressure continues to slowly rise. If

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Figure 12-6.-Buildup and supply mode (Converter Installed).

12-20

Figure 12-7.—Converter installed in an aircraft.

allowed to go unchecked, pressure in excess of12,000 psig could be generated. To prevent thispotentially hazardous situation, a relief valve isincorporated. The relief valve is set to relieveexcess pressure in the converter assembly atapproximately 110 psig.

9. As a demand is placed on the converterby the aircrewman, LOX is forced into thebuildup coil to replace consumed oxygen. As thisprocess is repeated, the LOX level in the converterdrops, increasing the void area at the top. As thesize of the void area increases, pressure decreases,and is sensed by the bellows in the pressure closingvalve. When pressure falls below approximately75 psig, the bellows expand, opening the valve.With the valve open, pressure from the buildupcoil passes through the valve and into the top ofthe converter. This pressure, coupled with thepressure created by vaporizing LOX contained inthe converter, again builds to approximately 75psig and closes the pressure closing valve. This

process is repeated as long as a demand is beingplaced on the converter.

10. A heat exchanger is incorporated into theaircraft tubing to further warm the gaseousoxygen to a breathable temperature.

11. An additional relief valve, set at approx-imately 115 psig, is installed in the aircraftoxygen plumbing to provide additional protectionagainst overpressurization of the converter andsupply lines of the system.

PERFORMANCE TESTING

To be sure the converter is functioning, a seriesof bench tests is made. These tests are madeusing the test stand and the test stand calibrationcorrection cards, shown in figure 11-6 in chapter11 of this manual.

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Figure 12-8.—Converter performance test sheet (Sheet 1 of 2).

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Figure 12-8.—Converter performance test sheet (Sheet 2 of 2).

PERFORMANCE TEST test stand. Refer to chapter 11 for calibrationSHEET PREPARATION

Preparation of the liquid oxygen converterPerformance Test Sheet (fig. 12-8), which isused for the performance test and for the benchtest described later, requires entering theappropriate indicated flows and pressures in thespaces provided. The indicated flows andpressures are extracted from the test stand calibra-tion correction cards (fig. 11-6 of chapter 11).

The test stand calibration correction cardscontain all actual flows and pressures required totest all known models of liquid oxygen converterspresently in service. Converting actual flows andpressures to indicated flows and pressures isnormally accomplished during calibration of the

intervals.

The Performance Test Sheet is prepared asshown in figure 12-8. The Performance Test Sheetshown is a sample, but may be reproduced forlocal use.

The following tests require the extraction ofappropriate indicated flows and/or pressures fromthe test stand calibration correction cards (figure11-6 of chapter 11).

Relief valve test

Converter leakage test

Fill and buildup time test

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. Flow test

. Converter charge

RELIEF VALVE

The relief valve vents at least 100 liters perminute (lpm) with an applied pressure of 100 to120 psig. The maximum allowable leakage with95 psig applied is 0.01 lpm. Make the followingentries on the performance test sheet:

1. Locate the indicated inches of water (inchof H2o) for 100 lpm on correction card 4. Enterindicated inches of H2O in the space provided onthe performance test sheet.

2. Locate the indicated psig for the actualpressures of 95, 100 and 120 psig on correctioncard number 2. Enter indicated psig in spaceprovided on performance test sheet.

3. Locate the indicated inches of H2O for theactual flow of 0.01 lpm on correction card number7. Enter the indicated in. H 2O in spaceprovided on performance test sheet.

CONVERTER LEAKAGE

The converter leakage test is performed withthe converter pressurized with gaseous oxygen to95 psig. Locate the indicated psig for the actual95 psig on correction card number 2. Enterindicated psig in space provided on performancetest sheet.

FILL AND BUILDUP TIME

The time required to fill the converter (10liters) should not exceed 10 minutes at a fillingpressure of 30 psig.

The time required for the filled converter tobuildup to a working pressure of 70 psig shouldnot exceed 5 minutes from time the servicingtrailer filler valve is disconnected from converter.Locate indicated psig for the actual 70 psigpressure on correction card number 2. Enterindicated psig in space provided on performancetest sheet.

FLOW

The converter can deliver gaseous oxygen ata flow rate of 120 lpm while maintaining a

pressure of 55 to 90 psig. Make the followingentries on the performance test sheet:

1. Locate the indicated inches of H2O for theactual flow of 120 lpm on correction card number4. Enter indicated inches of H2O in spaceprovided on performance test sheet.

2. Locate the indicated psig for actualpressures of 55 and 90 psig on correction cardnumber 2. Enter actual psig in spaces providedon performance test sheet.

CONVERTER CHARGE

Upon completing the bench test, the converteris emptied of LOX, purged with nitrogen, andpressurized with gaseous oxygen at 25 to 30 psig.This prevents moisture from entering theconverter during shipment/storage. Locate theindicated psig for the actual pressures of 25 to 30psig on correction card number 2. Enter indicatedpsig in spaces provided on the performance testsheet.

MAINTENANCE

This section contains the procedural steps forinspecting, testing, troubleshooting, disassembly,cleaning, repair, assembly and adjusting of theGCU-24/A liquid oxygen converter assembly(P/N 10C-0016-10).

Procedural steps outlined in this section arelisted under the inspection cycle in which they arerequired, and in the sequence in which theynormally occur.

ACCEPTANCE/TURNAROUND/DAILY/PREFLIGHT/POSTFLIGHTAND TRANSFER INSPECTIONS

The acceptance/turnaround/daily/preflight/postflight and transfer inspections consist of avisual inspection followed by a functional test.These inspections and tests are performed alongwith the aircraft inspection requirements for theaircraft in which the converter is installed. Inmaking the following checks, if you discover anydefects, refer to table 12-17 for troubleshootingassistance.

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Table 12-17.—Troubleshooting (Acceptance/Turnaround/Daily/Preflight/Postflight and Transfer Inspections)

VISUAL INSPECTION 7. Security of supply,quick-disconnects.

vent and electrical

Visually inspect the converter assembly and - 8. Excessive frosting of converter assembly.surrounding area for the following:

9. Ensure date on converter bench test decal1. Freedom from dirt and hydrocarbons.2. Correct installation and positioning of all

components, safety wire, and Glyptal dots.3.4.

valves5.

is current (within last 231 days).

Legibility of all markings.Cracks, dents or other damage toand electrical connections.Corrosion on converter assembly and functional test should also be performed by the

FUNCTIONAL TESTtubing,

In addition to the scheduled test, the

surrounding areas. AME whenever a component of the aircraft6. Obstructions in aircraft overboard vent oxygen system is removed/replaced. As a PR you

line. may be called upon to perform this test. To

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functionally test the converter assembly and air-craft oxygen system, proceed as follows:

1. Ensure all circuit breakers associated withthe LOX quantity indicating system are set.External electrical power must be applied to theaircraft to perform steps 2 and 3 below.

2. Depress oxygen test switch. Check thequantity gauge and low warning light for properoperation. Refer to the applicable aircraft Hand-book of Maintenance Instructions (HMI) todetermine at what quantity (indicated on quantitygauge) that the low warning light shouldilluminate.

3. Release test switch. Ensure gauge pointerreturns to position registered on gauge beforedepressing. When test is completed, disconnectelectrical power for aircraft.

4. Ensure oxygen shutoff valve is in the OFFposition.

5. Attach an oxygen mask, regulator andregulator-to-seat kit hose assembly to oxygensupply connection in aircraft.

6. Turn oxygen shutoff valve to the ON posi-tion. There should be a flow of oxygen throughthe mask.

7. Place the mask against your face andbreathe. There should be a slight resistance duringexhalation. This resistance is due to the positivepressure feature of the regulator.

8. Upon completing the functional test, turnthe oxygen shutoff valve to OFF. Disconnect theregulator-to-seat kit hose from the aircraft supplyconnection.

If discrepancies are found or suspected, notifymaintenance control.

Components of the aircraft oxygen system thatdo not pass inspection and cannot be repaired inthe aircraft are removed and replaced by readyfor issue (RFI) components.

CALENDAR INSPECTION

All liquid oxygen converters are given thecalendar inspection before they are placed in

Table 12-18.—Visual Inspection of Type GCU-24/A Liquid Oxygen Converter (P/N 10C-0016-10)

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service, and at intervals not exceeding 231 daysthereafter. This interval applies to all converters;aircraft-installed, shop spares, and those main-tained in a servicing pool.

The calendar inspection consists of a visualinspection followed by a bench test. All work isperformed in a clean, dust-free and oil-free area.Converter assemblies found to be damaged or outof adjustment are repaired by replacing oradjusting the discrepant part or parts. Afterrepair, repeat the bench test.

VISUAL INSPECTION

Visually inspect the converter assembly inaccordance with table 12-18.

Liquid oxygen converters failing the visualinspection or bench test are repaired, if the specificrepair is authorized. SM&R maintenance isauthorized to perform repairs. Further explana-tion is found in Naval Aviation MaintenanceProgram (NAMP), OPNAV 4790.2 (series).

SERVICE LIFE

Liquid oxygen converters can remain in serviceas long as they continue to function properly.

BENCH TEST

The bench test is performed using the LiquidOxygen Converter Test Stand P/N 59A120,31TB1995-1 or 31TB1995-4. Refer to chapter 11for identification of test stand controls andindicators referenced in bench test procedures. Donot attempt to perform any bench test withoutfirst becoming thoroughly familiar with the teststand. Use Performance Test Sheet (fig. 12-8)when performing the bench test.

The following tools and materials are requiredfor this test:

In the following descriptions, the tests are ar-ranged so they proceed from one test to the nextwith a minimum o f f l o w changes.Troubleshooting tables accompany many of thetests.

The first step in the bench test is to find thetare weight of the converter. Tare weight is theweight of the complete converter assembly less theweight of the LOX. Proceed as follows:

1. Ensure all LOX has been removed from theconverter.

2. Place the converter assembly on scaleshaving at least a 50-pound capacity. Recordweight in space provided on performance testsheet.

CONVERTER ASSEMBLY PURGE

As we mentioned before, the converter shouldbe purged before any test. This purging is the keyto a trouble-free operating converter. Only dry,oil-free nitrogen, Type I, Class 1, Grade A (FEDSPEC BB-N-411) is to be used for purging con-verters. While operating purging unit, you haveto wear protective gloves. The discharge fittingscan reach temperatures that will cause severeburns if grasped with bare hands.

Before starting to purge the unit, empty it ofLOX and allow it to warm to room temperature.Then proceed as follows:

1. Cap the converter quick-disconnect cou-pling assembly and attach a drain line to thequick-disconnect coupling assembly.

2. Ensure the purge unit power switch is OFF.Connect the purging unit electrical power cableto a suitable electrical power source.

3. Open the N2 supply cylinder valve and thepurge unit inlet valves.

4. Turn the purge unit power switch ON, andallow the unit to warm up approximately 10minutes.

5. Measure the outlet temperature of thepurge unit using a thermometer, GG-T-336, Type2, Class D or equivalent. Temperature should bebetween 200 °F (93 °C) and 250°F (121 °C) priorto connecting the purge unit to converter.

6. Connect the purging unit to the fill,buildup, and vent valve of converter.

7. Purge the converter assembly. Themaximum inlet pressure and temperature shouldbe 55 psig and 250 °F, respectively. The purge timefor 10-liter LOX converters which are at ambienttemperature is from 45 to 75 minutes.

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8. When purging is completed, turn the purgeunit power switch OFF, secure the N2 supplycylinder valve and the purge unit inlet valves.Disconnect the purge unit from the converter.

NOTE: Should the unit fail a test, the firststep of the repair action is to repurge theunit.

INSULATION RESISTANCE TEST(EMPTY)

To perform the insulation resistance test,proceed as follows:

1. Secure the empty converter in the rackprovided on the test stand countertop.

2. Using the test stand cable assembly,connect the upper terminals of the highcapacitance cable assembly to terminals A and Bof the liquid oxygen quantity gauge capacitancetype tester.

3. Turn the power switch ON and allow thetester to warmup 10 minutes prior to proceeding.

4. Turn the MEGOHMMETER RANGESELECTOR to its X-1 position.

5. Turn the FUNCTION SELECTOR knobto the A AND B position. Record the reading onthe meter in the space provided on thePerformance Test Sheet. Reading should not beless than 2.0 megohms.

6. Turn the FUNCTION SELECTOR knobto A TO GROUND and B TO GROUNDpositions respectively. Record the readings inspaces provided on the Performance Test Sheet.Readings should not be less than 1.0 megohm ineither position.

7. If insulation resistance readings are lessthan allowed, connect the cable assembly to thelower probe terminals, and repeat steps 5 and 6.

8. If readings are acceptable, replace the highcapacitance cable with the low capacitanceassembly. Repeat steps 5 and 6. If readings areacceptable, proceed to step 11.

9. If readings continue to be less thanacceptable, moisture may still be present in thesphere assembly. Purge the converter and repeatthe test.

10. Converter assemblies that fail the insula-tion resistance test, and cannot be corrected byreplacing the low or the high capacitance cableassembly or by purging, are condemned.

11. Leave all connections unchanged and startthe capacitance test (empty).

CAPACITANCE TEST (EMPTY)

To perform the capacitance test, proceed asfollows:

1. Turn the CAPACITANCE RANGESELECTOR knob to the X-10 position.

2. Turn the FUNCTION SELECTOR knobto its CAPACITANCE (UUF) position.

3. Record the meter reading in the spaceprovided on the Performance Test Sheet. Readingshould be 121.5 to 125.5 micro-microfarads(UUF).

4. If this reading is not within these limits,moisture may still be present in the sphere. Purgeconverter again and repeat the capacitance test.

5. Converter assemblies that fail thecapacitance test and cannot be corrected bypurging are condemned.

6. Turn the power switch off and disconnectthe test stand cable assembly.

RELIEF VALVE TEST

To follow this description, you will find ithelpful to refer back to figure 11-4 of the teststand in chapter 11. To perform the relief valvetest, proceed as follows:

1. Disconnect low and high capacitance cableassemblies from lower probe terminals.

2. Disconnect the buildup tube assembly fromthe buildup port of the fall, buildup and ventvalve, and from the pressure closing valve. Holdthe 45-degree elbows with open-end wrench toprevent turning while loosening tube nutconnections.

3. Cap 45-degree elbow in buildup port of fill,buildup and vent valve.

4. Using Test Stand Hose Assembly, P/N59A120-B5-14, connect test stand BELL JARBOTTOM COUPLING C-1 to the 45-degreeelbow on converter pressure closing valve.

5. Using the Test Stand Hose Assembly P/N59A120-B5-52, connect the converter quick-disconnect coupling to the test stand FLOW-METER CONNECTION, NIP-4.

6. Turn the FLOWMETER SELECTORvalve V-1 to the 0-150 lpm position. Open theTEST PRESSURE GAUGE-TO-BELL JARvalve, V-2.

7. Open the OXYGEN SUPPLY valve, V-6,slowly. Damage to test stand gauges could resultfrom rapid surges in pressure if this valve isopened too rapidly. Pressure applied will beindicated on TEST PRESSURE GAUGE, PG-1.

8. The relief valve relieves a minimum rate of100 lpm, as indicated on the FLOWMETER

12-28

INDICATOR GAUGE, PG-2, with a pressure of100 to 120 psig, as indicated on the TESTPRESSURE GAUGE, PG-1, applied to theconverter. Record these readings on the Per-formance Test Sheet.

9. Using the OXYGEN SUPPLY valve, V-6,and the SYSTEM BLEED valve, V-5, reduce thepressure applied to the converter to 95 psig asindicated on gauge PG-1.

10. Disconnect the test stand hose from theFLOWMETER CONNECTION, NIP-4 andreconnect it to the FLOWMETER CONNEC-TION, NIP-1.

11. Turn the FLOWMETER SELECTORvalve V-1 to the 0.0-0.25 lpm position.

120 While maintaining 95 psig to the converterwith valve V-6, check for leakage indicated on theFLOWMETER INDICATOR, PG-2. Maximumallowable leakage is 0.01 lpm. Record this readingon the Performance Test Sheet.

13. If leakage is excessive, or if the relief valvefails to vent at the required flow and pressure,locate the probable cause using TroubleshootingChart Relief Valve Test (Table 12-19).

14. Close OXYGEN SUPPLY valve, V-6.Bleed the test stand using SYSTEM BLEED valve,V-5. Close TEST PRESSURE GAUGE-TO-BELL JAR valve, V-4.

15. Disconnect both the test stand hoseassemblies from the converter and from the teststand.

16. Uncap the 45-degree elbow that youcapped in step 3, and reconnect the buildup tube,which you removed in step 2.

17. Reconnect the high and low capacitancecable assemblies, which you removed in step 1.At this time, ensure that all safety wired setscrewshave the proper Glyptal dots applied.

CONVERTER LEAKAGE TEST

To test the converter for leaks, proceed asfollows:

1. Using Test Stand Hose Assembly, P/N59A120-B5-47, connect the test stand BELL JARBOTTOM COUPLING C-1 to the converterquick-disconnect coupling.

2. Open the TEST PRESSURE GAUGE-TO-BELL JAR valve, V-2.

3. Using the OXYGEN SUPPLY valve, V-6,slowly apply 95 psig, as indicated on TESTPRESSURE GAUGE, PG-1, to the converter.

4. Maintain 95 psig and inspect for leakageat all connections using leak detection compound(MIL-L-25567). There should be no leakage. Ifany leakage is found, locate its probable causeusing the troubleshooting chart (table 12-20).

Table 12-19.-Troubleshooting (Relief Valve Test)

Table 12-20.-Troubleshooting (Converter Leakage Test)

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5. Close OXYGEN SUPPLY valve V-6. Bleedthe test stand using SYSTEM BLEED valve V-5.Close TEST PRESSURE GAUGE-TO-BELLJAR valve V-2.

6. Remove the converter assembly from teststand.

FILL AND BUILDUP TIME TEST

To perform the fill and buildup time test, itwill be necessary to take the converter to a LOXservicing area, or use a LOX servicing trailer inthe immediate area of the oxygen shop. Any othermethod is acceptable that meets requirements ofthe test, and does not violate safety precautions.Remember, LOX requires special precautions.

Once the converter is in a satisfactory loca-tion, proceed as follows:

1. Attach a vent drain line to the converterquick-disconnect coupling. This line should belong enough to route venting LOX away from allpersonnel.

2. Attach the pressure gauge/relief valve testfixtures to the supply quick-disconnect coupling(refer to NAVAIR 13-1-6.4).

3. Attach the servicing trailer filler valve tothe converter fill, buildup, and vent valve.

4. Note the time, and start filling theconverter. Maintain a filling pressure at 30 psig.

5. The converter is full when a steady streamof LOX flows from the drain line. When theconverter is full, note the time. The time requiredto fill the converter at 30 psig should be no longerthan 10 minutes. Record the fill time in theappropriate space on the Performance Test Sheet.

6. Note the time, and disconnect and securethe servicing trailer. The time noted at this pointis the beginning of the buildup time test.

7. Observe the pressure gauge on the quick-disconnect coupling. On the performance testsheet, record the time it takes the converterassembly to buildup to a working pressure of 70to 80 psig. This time should not exceed 5 minutes.

8. If discrepancies were noted in either partof the test, locate the probable cause using thetroubleshooting chart (table 12-21).

9. Remove the vent drain line and the pressuregauge/relief valve test fixture you installed in steps1 and 2.

CAPACITANCE TEST (FULL)

The capacitance test requires simultaneous useof the 50-pound scales and the quantity gaugecapacitance type tester incorporated in the teststand. Ensure the scales are positioned closeenough to the tester, then proceed as follows:

1. Place the full converter on the scales.2. Using the test stand cable assembly,

connect the upper terminals of the converter highand low capacitance cable assemblies to terminalsA and B, respectively, of the liquid oxygenquantity gauge capacitance type tester.

3. Turn the power ON and allow the testerto warm up 10 minutes before proceeding.

4. Turn the CAPACITANCE RANGESELECTOR knob to its 10X position.

5. Turn the FUNCTION SELECTOR knobto the CAPACITANCE (UUF) position.

6. Enter the total weight of the full converterin the space provided on the performance testsheet.

7. Subtract the tare weight of the converterfrom its total weight. Enter this figure on thePerformance Test Sheet. This is the weight ofLOX in the converter.

8. Using the formula given on the Perform-ance Test Sheet, 2.33 x W + 124.7 = C(max),calculate the capacitance maximum (C-max). Usethe weight of LOX for W. Enter the result of thecalculation in the space provided.

9. Use the formula 2.25 x W + 122.3= C(min) and calculate the capacitance minimum(C-tin) on the next line of the test sheet. Use theweight of LOX for W.

Table 12-21.—Troubleshooting (Fill and Buildup Time Test)

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10. Observe and record capacitance readingfrom test stand capacitance gauge in spaceprovided on Performance Test Sheet. Readingshould be between C(max) and C(min).

11. If the test is not within these limits andthe converter has not been purged in previoustests, there may be moisture in the sphere. Purgethe converter and refill it with LOX, then repeatsteps 1 through 11.

12. If the converter is still not within limits,condemn the converter.

13. Secure the tester and disconnect the cablesfrom the converter and tester. If the converterpasses capacitance test, carefully remove it fromthe scales and allow it to remain undisturbed for1 hour.

EVAPORATION LOSS TEST(BUILDUP AND SUPPLY MODE)

To perform the evaporation loss test inthe buildup and supply mode, proceed asfollows:

1. At the end of the 1 hour period, gentlyplace the converter on the scales and record itsweight and the start time in the spaces providedon section 8 of the Performance Test Sheet.

2. Place the converter assembly aside againand allow it to remain undisturbed for 24hours.

3. At the end of the 24-hour period, carefullyreplace the converter on the scales.

4. Record the time and weight in the spacesprovided on the Performance Test Sheet. The 24hour weight loss must be less than 3 pounds.There should not be a heavy coat of frost on thesphere.

5. If the weight loss was 3.0 pounds or less,and there was not excessive frosting of the sphereassembly, proceed to the flow test. If theloss was more than 3.0 pounds, proceed to theEVAPORATION LOSS TEST.

EVAPORATION LOSS TEST(VENTED MODE)

Maximum allowable loss of LOX in 24 hoursis 5.0 pounds. Minimum allowable loss is definedas the weight recorded during the buildup andsupply mode minus 0.5 pound (performed onlyif converter fails evaporation loss test in buildupand supply mode).

To perform the evaporation loss test in thevented mode, proceed as follows:

1. With the converter still on the scales,attach the test stand fill valve adapter (P/N59A120-D5-10) to the fill, buildup, and vent valveon the converter.

WARNING

VENTING A CONVERTER THAT IS INA BUILDUP AND SUPPLY MODECAUSES A BLAST OF LOX FROMTHE VENT PORT. ENSURE THATVENT BLAST IS DIRECTED AWAYFROM ALL PERSONNEL, AND THATADEQUATE CLOTHING AND FACIALPROTECTION ARE WORN.

2. Turn the knurled knob of the adapter inuntil it seats. This places the converter in thevented mode.

3. Record the time and weight in section 9 ofthe Performance Test Sheet.

4. Place the converter aside and allow it toremain undisturbed in the vented mode for 24hours.

5. At the end of the 24-hour period, carefullyreplace the converter on the scales.

6. Record the time and the converter weighton the Performance Test Sheet. Weight loss in 24hours should not exceed 5.0 pounds for this testto be satisfactory.

7. If the weight loss is too much, locate theprobable cause by using the troubleshooting chartin table 12-22.

Table 12-22.—Troubleshooting (Evaporation Loss Test)

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Table 12-23.-Troubkshooting (Flow Test)

8. Remove the fill valve adapter you installedin step 1.

FLOW TEST

To perform the flow test, proceed as follows:

1. Secure the converter in the rack on the teststand countertop.

2. Using the Test Stand Hose Assembly, P/N59A120-B5-12, connect the test standFLOWMETER CONNECTION, NIP-4, to theCONVERTER SUPPLY OUTLET CONNEC-TION, NIP-5.

3. Using the Test Stand Hose Assembly, P/N59A120-B5-47, connect the test stand SUPPLYTO CONVERTER CONNECTION, NIP-6, tothe converter quick-disconnect coupling.

4. Place the test stand FLOWMETERSELECTOR valve V-1 in the 0-150 1pm position.Open the TEST PRESSURE GAUGE BUILDUPAND FLOW valve V-10. You should not havea reading of over 70 psig on the test pressure gaugePG-1. If the test pressure gauge reads over 70 psig,vent the converter system pressure to 70 psig (referto NAVAIR 13-1-6.4).

5. Open the test stand CONVERTER SUP-PLY FLOW CONTROL valve, V-9, to give af low o f 120 1pm as ind icated on theFLOWMETER INDICATOR gauge, PG-2.Maintain the flow for a minimum of 15 minutes.

6. While maintaining a 120 1pm flow, theconverter should maintain pressures of 55 to 90psig as indicated on the TEST PRESSURE gauge,PG-1. Record the high and low pressures in theindicated blocks in section 10 of the PerformanceTest Sheet.

7. If the converter supply pressure is notwithin limits, locate probable cause using thetroubleshooting chart (table 12-23).

8. Continue flowing the converter until it iscompletely empty of LOX. Any means ofevacuating LOX from the converter is acceptable,provided all safety precautions are followed.

9. Disconnect the test stand hose assemblies,which you attached in steps 2 and 3. Close all teststand valves.

CONVERTER CHARGE

Upon completion of the bench test, theconverter is charged with gaseous oxygen to 25to 30 psig to prevent entry of moisture and othercontaminants during shipment/storage. To chargethe converter, proceed as follows:

1. Secure the converter in the rack on the teststand countertop, unless it is already there.

2. Using the Test Stand Hose Assembly, P/N59A120-B547, connect the test stand BELL JAR

Figure 12-19.—Bench test decal.

12-32

BOTTOM COUPLING, C-1, to the converterquick-disconnect coupling.

3. Open the TEST PRESSURE GAUGE-TO-BELL JAR valve, V-2.

4. Opening the OXYGEN SUPPLY valve,V-6, slowly charge the converter to 25 to 30 psig.Pressure will be indicated on the TESTPRESSURE gauge, PG-1.

5. Close the OXYGEN SUPPLY valve, V-6.Disconnect the hose assembly connected in step2, and bleed the test stand using SYSTEMBLEED valve, V-5. Secure all test stand valves.

6. At this point, enter the amount of theconverter charge in section 11 of the Performance

Test Sheet, and you and a CDI sign the sheet. Theoriginal, or a copy of the Performance Test Sheetis forwarded to the operational custodian of theconverter.

7. Mark the due date of the next bench teston the bench test decal (fig. 12-9). Due date is 231days from the last bench test date. Affix this decalto the converter in a position in which it will bevisible when the converter is installed in anaircraft.

8. Install dust covers or plugs in/on all opencouplings prior to shipping or storage of theconverter.

12-33

APPENDIX I

GLOSSARY

ABRASION—A fuzzy spot or area on cloth,usually caused by rubbing against an object.

ACC—Abbreviation for aircrew systemschange.

ACCORDLAN-FOLDS—Folding a canopyinto S-shaped layers of predetermined size.Accordian folding produces a packaged parachuteassembly in the desired finished shape.

ACID—A fundamental chemical classdistinguished by having reactive hydrogen radicals(pH below 7.0). Acids can be extremely corrosiveto metal and damaging to fabric.

ADAPTER, HARNESS—A rectangularmetal fitting with a fixed crossbar used primarilyas an anchoring point.

ADAPTER, HARNESS FRICTION—Arectangular metal fitting with a movable centerbar (friction grip). Facilitates quick adjustmentof a harness by the wearer.

AIRCREW MEMBER—An aircraft crewmember. Passengers are not considered aircrewmembers.

ALKALINE—A substance that is opposite toan acid, a base. Also, any substance that has theproperties of an alkali (metallic hydroxide).

ANEROID—A corrugated metal capsule usedin the automatic parachute ripcord release forsensing atmospheric pressure. The aneroid willinitiate operation of an actuator at a presetaltitude.

ANTI-SEIZE TAPE—A tape of any ofseveral thin plastic-film materials (such astetrafluoroethylene) characterized by a waxy, oilytexture, and used to prevent binding betweenmating surfaces of threaded parts when appliedto the male threaded portion.

APPROX—Abbreviation for approximately.

ASSEMBLY—A grouping of parts fittedtogether to form a complete unit.

ATMOSPHERIC PRESSURE—Pressure atsea level, expressed as 14.696 pounds per squareinch, absolute, or 29.92 inches mercury column(barometer). See also PSIA and IN. HG.

AUTOMATIC PARACHUTE RIPCORDRELEASE—A barometrically controlled devicethat mechanically or by explosive force actuatesthe parachute ripcord assembly, causing theparachute container to open at a preset altitude.

AWL—A pointed tool for piercing small holesin cloth, leather, wood, and other soft materials.

BACKSTITCH—A stitch made by insertingthe needle a stitch length to the right and bringingit up an equal distance to the left. Also, sewingback over a row of stitches.

BAG, SHOT—A bag filled with lead shotused to hold the canopy in place during packing.

BAG, DEPLOYMENT—A canvas enclosurefor the canopy and suspension lines. In use,the deployment bag controls release of suspensionlines and canopy, ensuring orderly opening.

BALL, CABLE RETAINING—A steel ballthat is swaged to the ripcord cable and securesthe ripcord handle to the cable.

BAND, LATERAL—Webbing inserted incanopy skirt and vent hems to reinforce edges anddistribute load.

BAND, POCKET—A piece of tape or lineattached at the skirt hem and across the radialseam, which causes the gores to be pulled outward

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at inflation, thus improving the openingcharacteristics of the canopy.

BAND, RETAINING—A rubber band usedto hold folded suspension lines in a container orfaked lines together.

B A R R E L , A U T O M A T I C P U C H U T ERIPCORD RELEASE—That part o f anautomatic parachute ripcord release that housesthe cartridge and piston or spring and piston.

BARTACK—A concentrated series of zig-zagstitches used to reinforce points of stress. Abartack should have 28 stitches per half-inch (perMIL-O-81900AS).

BEESWAX—A wax, generally with paraffin,that is applied cold or melted to thread to preventraveling or cloth unknotting and to make threadeasier to sew.

BIAS CONSTRUCTION—A type of canopyconstruction in which the canopy cloth is cut andsewn so that the centerline of each gore runs ata 45-degree angle to the warp and filling threadof the canopy cloth.

BINDING—A piece of tape or fabric foldedover and stitched to a raw edge of cloth to preventraveling or fraying.

BODKIN—A large-eyed, blunt needleinstrument for inserting thread, tape, ribbon, orline through a loop, hem, or channel. Used to feedsuspension lines through canopy radial seams orto stow suspension line bights in certain parachutecontainer assemblies.

BOLT—A package or roll of cloth of varyingwidths. Also, a measuring term for 40 yards ofmaterial.

BOTTOM, FALSE—Apiece of cloth sewn tothe inside of a pack to retain the frame. It alsoserves as a base for attaching suspension linehesitater loops.

BRAID—A narrow band of interlacedstrands.

BREATHING—The pulsating action of theparachute canopy when fully inflated.

BUNCHED STITCHING—Stitches too closeor more stitches per inch than required.

BURL—A knot or lump in thread or cloth.

BURNS, FRICTION—A hard spot on thesuspension line caused by two lines rubbingtogether at high speeds, generally off-color andbrittle.

C—Abbreviation for Celsius.

CABLE, ARMING, AUTOMATIC PARA-CHUTE RIPCORD RELEASE—A cable that,when attached to the ejection seat, lap belt, orother designated point, arms the automaticparachute ripcord release at seat/man separation.

CABLE, POWER, AUTOMATIC PARA-CHUTE RIPCORD RELEASE—A cable coveredby a housing, which transmits the force from theautomatic ripcord release assembly to the ripcordcable.

CABLE, RIPCORD—A flexible cable joiningthe locking pins and ripcord handle.

CANOPY—The main supporting surface ofa parachute that, when opened, reduces the rateof descent. It is usually made of nylon andincludes a framework of cords, called suspensionlines, from which the load is suspended.

CANOPY, CONICAL—A canopy con-structed in the shape of a cone. See alsoCANOPY.

CANOPY, EXTENDED SKIRT—A canopythat has a flat circular center or disk when spreadout. See also CANOPY.

CANOPY, FLAT CIRCULAR—A canopythat has the shape of a flat circle or disk whenspread out. See also CANOPY.

CANOPY, GUIDE SURFACE—A mush-room-shaped canopy in which alternate roofpanels are extended to provide guide surfaces. Seealso CANOPY.

CANOPY, HEM-RIGGED—A canopy thatthe suspension lines are attached to the skirt hemand do not pass over the drag-producing surface;for example, the 26-foot conical canopy. See alsoCANOPY.

CANOPY, RIBBON—A canopy composed ofconcentric cloth ribbons, supported by radialribbons and tapes. See also CANOPY.

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CANOPY, RINGSAIL—A canopy com-posed of concentric rings installed on aspherical surface. The slots that are contained inthe gores are in the form of a crescent. See alsoCANOPY.

CANOPY, RING SLOT—A canopy com-posed of concentric cloth strips with interveningair slots. The number of slots will vary with thediameter of the canopy. See also CANOPY.

CANVAS—A heavy, closely-woven cloth oflinen, cotton, or synthetic fiber.

CASING (SLEEVE)—The outer woven coverof the suspension line.

CAUTION—Indicates danger to equipment.The caution precedes the step or item to whichit refers.

CcM—Abbreviation for cubic centimeters perminute.

CDI—Abbreviation for collateral dutyinspector.

CHANNEL, CANOPY—The space or open-ing formed by the overlapping of cloth in makingof radial seams. The suspension lines pass throughthe channels and are retained in position. Thechannels aid in transmitting load from the linesto the cloth.

CHUTE—Abbreviated s lang form o fparachute.

CLAMP, DUAL HOUSING—A metal clamplocated on the outside of the end flap of back-and seat-type parachutes. The clamp secures theripcord and power cable to the container end flap.

CLEVIS—A U-shaped metal fitting with ahole in each end to receive a pin or bolt.

CLIP—A device that fastens, holds togetheror retains; for example, the clip that is tacked toa riser and holds the ripcord housing in place.

CLOTH, CANOPY—The cloth used inparachute canopies. It is woven to withstand theimpact of air pressure when the parachute opens.The canopy cloth is woven from nylon yarns,usually in a ripstop weave. See also CANOPY.(Ref. MIL-C-7020, Cloth, Nylon, Parachute.)

CLOTH, NYLON RIP-STOP—A type ofnylon cloth used in canopy manufacture. Theweave pattern of the nylon cloth consists ofreinforced ribs, in both the warp and the filling,forming a uniform pattern of squares. The clothis designed to keep hole damage to a minimumwhen rips or tears develop in the canopy.

CLOVERLEAF HANDLE—A r ipcordhandle that is used on chest- and integrated back-type parachutes. It is shaped in the form of acloverleaf.

CO2—Abbreviation for carbon dioxide.

COLLAR, VENT—A strip of nylon cloth.One edge is sewn to the vent hem of the canopyso that a collar or cylinder is formed above thetop of the parachute. The other edge is hemmedto form a channel for the insertion of a moldedrubber ring.

C O M B U S T I B L E M A T E R I A L / S U B -STANCE—Any material or substance capableof burning in the presence of oxygen. See alsoEXPLOSIVE MIXTURE, FLAMMABLEMATERIAL.

COML—Abbreviation for commercial. Refersto parts that are commercially available.

COMPONENT—Item of equipment makingup part of an assembly; for example, a ripcordhousing is a component part of a ripcordassembly.

CONE, LOCKING—A small, smooth, cone-shaped metal post sewn to the flaps of thecontainer or inside the vane-type pilot parachute.The cone has a horizontally drilled hole a shortdistance from the top to admit a temporarylocking pin or the ripcord pin. The pilot parachutelocking cone contains two holes. The flangecontains holes for securing purposes.

CONFIGURATION—The makeup, size,shape, and relative location of parts of an itemof equipment and its accessories. This includes thecomposition of the materials as well as markingdetails. The configuration of each equipment isspecified by Government drawings, militaryspecifications and modification instructions.

CONFLUENCE POINT—A coming orrunning together of two or more lines.

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CONTAINER—An assembly that enclosesand protects the canopy, suspension lines, andrisers until the parachute is opened. Sometimescalled the pack assembly.

CONTAINER, HARDSHELL—A containerthat has a rigid plastic or fiber body with clothend and side flaps, designed to withstand highwind-blast conditions; for example, the NES-8Bparachute container and certain MBEU parachutecontainers.

CONTRASTING COLOR—A color thatstands out from its background.

CONTROLLER DROGUE—A small para-chute that is used to extract the stabilizer drogueparachute.

CONVOLUTION—Used in this manual asthe protruding side or portion of a diaphragm.

CORE OVERLAP—During suspension linemanufacture, the insertion of an incoming coreyarn that runs parallel to a running out yarn,which results in two core yarn ends protrudingthrough the casing a distance of about 2 to 6inches. These ends are normally cut off duringfinal phase of parachute suspension linemanufacture.

CORDS, CLOSING—Made of type I nyloncord approximately 18 inches in length. They areused as an aid in the closing of the parachutecontainer.

CROSS BOX—A sewing pattern.

CROWN—A cloth panel used to cover thepeak of a vane-type pilot parachute. Also, theportion of the main canopy surface near the peak.

CUSHION, SEAT—A square, cloth-coveredpad designed to provide comfort and equippedwith a slot to provide passage for the harness legstraps.

CUTTER, PYROTECHNIC—A device thatis operated by an explosive charge and is used tocut line or webbing, etc.; for example, a static linecutter.

D-RING—A metal fitting shaped in the formof the letter D; for example, a D-ring on a harnessconnects to a chest-type parachute assembly by

means of snap fittings. Also, a slang term for theripcord handle.

DART—A short, tapered seam.

DELAYED RELEASE JUMP—A parachutejump in which the wearer purposely does not openthe parachute immediately upon safely clearingthe aircraft.

DIAMETER—The greatest straight distanceacross a circle. Specifically, the greatest distanceacross a flat canopy, from skirt to skirt, measuredwhen the canopy is lying flat. Used to designatethe size of a flat canopy.

DIAMETER, NOMINAL—The diameter ofa circle that has the same surface area as a givenparachute canopy. This measurement is used toallow comparison of all shapes (conical, spherical,etc.) of parachute canopies.

DIAMETER, PROJECTED—The greatestdistance between opposite points on the skirt hemwhen the canopy is inflated. The projecteddiameter is approximately two-thirds the diameterof a flat canopy.

DIP—A line or group of lines passing througha group of lines. Also, a group of suspension linesnot in proper continuity. See also TWIST.

DISPOSITION—Instructions on what is to bedone with or to an item.

DOUBLE-W—A sewing pattern.

DROP TEST—The release of a parachuteassembly with a dummy load from an airplane,tower, or ejection seat for testing purposes.

DRY LOCKER—A tower or compartment ofsuitable height that will satisfactorily air fullysuspended parachutes.

EJECTION SEAT—An emergency escapeseat for propelling an occupant out and awayfrom the aircraft by means of an explosive chargeor rocket motor.

EJECTOR BOARD—A small, rectangularboard with rounded edges and a grommet in oneend used on MBEU parachutes. It serves as a firmplace for the pilot parachute to spring from duringopening.

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ELASTOMER—Any of various elastic sub-stances resembling rubber.

EMERGENCY KIT, PAWCHUTE—Astandard soft pack, high-speed soft pack, specialkit or rigid seat survival kit containing a raft andsurvival equipment needed by an aircrewman incase of emergency.

END OUT (MISSING END)—A warp yarnmissing for a portion of, or the entire length of,cloth .

ENSURE—Make certain that necessary mea-sures are taken.

EXAMINE—To inspect closely, and to testthe condition of an item.

EXPLOSIVE MIXTURE—Any mixture of acombustible material or substance and oxygencapable of violent burning (detonation) eitherspontaneously or with the external application ofheat.

EYE—A small, steel-wire loop; for example,the loops attached to the parachute container, intowhich a hook on a container spring opening bandis fastened.

EYELET—A small metal reinforcement fora hole in cloth, similar to a grommet, exceptthinner and smaller, and having no washer. Theeyelet is used to reinforce lacing holes in smallcovers, etc.

in

F—Abbreviation for Fahrenheit.

FAKE—To fold a line, rope, cord, or hawsera back-and-forth fashion.

FASTENER, DIRECTIONAL—A snapfastener that can be engaged or released only inone direction.

FASTENER, NONDIRECTIONAL—A snapfastener that can be engaged or released byapplying pressure or pull from any angle.

FASTENER, SLIDE—A type of fastenermade of two lengths of tape with a series of metalor plastic scoops fastened to one side of each. Ametal slide is provided that causes the scoops tomesh or lock in place as the fastener is closed, orto separate as the fastener is opened. Colloquialusage ZIPPER.

FELT—A cloth made from wool, fur, hair,synthetic fiber, or a mixture of these with cotton.It is made by matting the fibers together underpressure and heat.

FERRULE—A cap or ring used to finish theend of a housing; for example, the finished endsof a ripcord housing.

FIBER—A natural or synthetic filament (asof wool, cotton, rayon, etc.) capable of beingspun into yarn.

FID—A small, flat hand tool of metalor wood used during the packing process tostraighten end flaps and to insert corner flaps intoa finished pack.

FILLING—Threads that are perpendicular toselvage edges, and extend across the width ofcloth .

FITTING ASSEMBLY, DISCONNECT—Areleasing device used on the LW-3B parachuteassembly, which detaches both the static lineand the ripcord assembly from the container sidepanel after either has effected opening of thecontainer.

FITTING, CANOPY QUICK-RELEASE—Adevice that connects the canopy and risersto the harness, permitting the aircrewman todisengage himself, on instant response, from thecanopy.

FITTING, OVERRIDE DISCONNECT—Adirectional fitting used on the NB-11, NES-12,and NES-16 parachute assemblies that connectsthe external pilot parachute and the pilotparachute.

FITTING, QUICK-RELEASE—A deviceused to connect and release on instant response.See a lso FITTING, CANOPY QUICK-RELEASE.

FITTING, SWAGE—A connection, adapter,or pin that is fastened to a cable by pressure. Itis applied by means of a machine that compressesthe fitting, causing it to tightly grip the cable orwire to which it is being attached.

FLAMMABLE MATERIAL—Any materialcapable of being easily ignited and of burning withextreme rapidity.

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FLAP, CORNER—One o f the smal l ,rectangular cloth tabs that are part of thecontainer side flaps and act as protection andreinforcement of the container corners when theparachute is packed.

FLAP, END—A cloth extension on the shortsides of the container base that folds over toenclose the canopy. One of the end flaps is usuallydesigned as the ripcord end flap.

FLAP, SIDE—A cloth extension on each ofthe long sides of the container base, which foldsover and encloses the canopy. Each side flap isdesignated according to the fittings it carries; forexample, locking cone side flaps or grommet sideflap.

FLARING—The process of opening orwidening; for example, the method of splitting,taping, and stitching the ends of webbing in orderto widen and prevent it from slipping through anadapter.

FLOAT, MULTIPLE—A place in clothwhere a series of floats extend 3/16 inch or more.

FLOAT, SINGLE—A place in cloth where afilling or warp yarn extends unbound over thepick(s) with which it should be interlaced.

FOLDER—A device used as an attachmentto a sewing machine to guide and fold cloth.

FRAME, CONTAINER—The frameworkused to stiffen and hold the container in shape.

FRAYED (SUSPENSION LINE)—A fuzzycondition in which short lengths or pieces ofthread or yarn protrude from surface ofsuspension line.

FREEZING POINT—Temperature at whicha given liquid substance will solidify or freezeupon removal of heat. Freezing point of water is32°F (0°C).

FULL—In reference to oxygen cylinders, afull oxygen cylinder is a cylinder that is pressurizedto its rated pressure. With respect to a high--pressure oxygen cylinder, 1800 psig is consideredfull.

FUNCTIONAL TEST—A test that puts anitem to use to determine if it operates properly.

GAPL—Abbreviation for Group AssemblyParts List. The GAPL, a section of the Illus-trated Parts Breakdown, shows how majorassemblies are dissembled into assemblies anddetail parts.

GORE—That portion of the canopy locatedbetween two adjacent radial seams and the ventand skirt hem. It consists of cloth sections sewntogether.

GROMMET—A metal eye and washer usedto reinforce a hole in material; for example,grommets on container side flaps.

H20—Abbreviation for water.

HANDLE, RIPCORD—The handle securedto the ripcord cable and retained in a pocketlocated on the harness or container. Pulling ofthe handle begins the process of parachuteopening. Often referred to as hand-pull or grip.

HARNESS—An arrangement of webbingstraps used to attach a parachute to theaircrewman. The harness serves as a sling tosupport the aircrewman during descent.

HARNESS, CHEST-TYPE—A harnessassembly used with attachable, chest-typeparachute.

HARNESS, MAIN SLING—The main load-carrying member of the harness. Formed by twolengths of webbing, it is routed from the shoulderadapters or D-rings down across the seat, up theside ending at the opposite adapters or D-rings.

HEAT EXCHANGER—Apparatus in whichheat is exchanged from one fluid to another.

HEAVY BAR OR PLACE—An area on clothwhere pick count varies from normal count. Seealso PICK.

HEM—A border or reinforced edge formedby folding cloth back and securing it, usually bysewing; for example, vent and skirt hem of aparachute canopy.

Hg—Abbreviation for mercury.

HOLE, CLOTH DAMAGE—Three or morewarp and/or filling threads broken at the samelocation.

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HOOK, PACKING—A special hook usedto draw suspension lines into place in hesitaterloops.

HOOK, TENSION—Hooks used to retain theconnector links during parts of the packingprocedure.

HOUSING, EXTENSIBLE RIPCORD—Aripcord and housing that can be extendedapproximately 4 inches to accommodate theaddition of a raft kit to the seat-type parachuteassembly.

HOUSING, RIPCORD—A flexible steel tubeencasing the ripcord cable used to protect againstaccidental release of damage and to serve as acable guide. Integrated ripcord assembly housingsare constructed of vinyl-coated flexible tubing.

IN.—Abbreviation for inches.

IND—Abbreviation for indicated.

IN. H20—Abbreviation for inches of watercolumn (27.68 in. H20 equals 1.0 psi equals 2.036in. Hg). See also IN. Hg.

IN. Hg—Abbreviation for inches of mercurycolumn. (0.07349 in. Hg equals 1.0 in. H2O) Seealso IN. H2O.

INNER CORE—Five to nine internal yarns(number depending on type) for suspension linesthat are covered by a woven sleeve or casing.

INSPECTION—A close examination fordamage, wear, and dirt. Also, regularly scheduledexamination of parachute assemblies. See alsoSERVICING PARACHUTES.

KEEPER—Small strip of tape or loop usedto retain an object; for example, riser and backpad keepers.

KIAS—Knots indicated air speed.

KICKPLATE—A platform on the NES-8Bparachute container that serves as a firm place forthe pilot parachute to spring from during opening.

KIT BAG, FLYER’S—A container made ofcanvas or nylon and reinforced with webbing,usually with a slide fastener opening. It is usedto carry the parachute and its accessories.

KNOT, BINDER—The simplest method ofjoining two threads or lines. The two ends areplaced side by side and a simple, overhand knotis then tied in both lines simultaneously. It willnot slip when drawn tightly. Also called a thumbknot.

KNOT, BOWLINE—A knot formed bymaking a small overhand loop a desired distancefrom the end of the line. The end of the line isthen passed through the loop from the undersideof the main part of the line and back through thesmall loop. When this knot is drawn tight, it willnot slip but still can be easily untied.

KNOT, CLOVE-HITCH—A knot formed bymaking one turn around a post, bringing the endacross the line, continuing around the post asecond time, and passing the end under the secondloop. Used to tie suspension lines to connectorlinks.

KNOT, HALF-HITCH—A knot formed bypassing a cord or line around an object, thenpassing the free end around the main part of thecord and bringing the free end up through the loopthus formed. It is used to finish the tying of thesuspension lines to the connector link and informing safety ties.

KNOT, LARK’S HEAD—A knot formedaround an attachment ring or bar by passing thefree ends of the line around the bar or though thering and then through a loop or bight in the line.This knot is used to attach pilot parachuteconnector straps.

KNOT, OVERHAND—A simple knot tied inthe end of a line by forming a loop and passingthe end over and down through the loop.

KNOT, SQUARE—A knot formed bypassingthe end of the cord in the left hand over and underthe end in the right hand, and then reversing theprocess by passing the end in the right hand overand under the one in the left hand.

KNOT, SURGEON’S—The surgeon’s knot issimilar to the square knot, except that the firstoverhand tie is wrapped twice around the cord orline.

LB—Abbreviation for pounds.

LIFT WEBS—The parts of parachute harnesswebbing or riser that extends from the connector

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links to the shoulder adapters, D-rings, or quick-release fitting.

LINE, ANTI-SQUID—A line attaching twosuspension line connector links to canopy ventlines on some parachute assemblies. The anti-squid lines are shorter than suspension lines andprevent the main canopy from squidding bybearing the load of the drogue parachute untilthe main canopy is fully opened. See alsoSQUIDDING.

LINE, DROGUE LINK—A line connectingthe withdrawal line to the drogue parachute onMBEU systems that do not employ a guillotine.The drogue link line contains a slide disconnectpin, which will separate the line and withdrawalline in case of manual parachute actuation.

LINE, SHORT ANTI-SQUID—A Martin-Baker patent improved anti-squid line, also calleda pull down vent line. See LINE, ANTI-SQUID.

LINE, STATIC—A line used to open aparachute assembly without the necessity ofpulling a ripcord manually. A static line isattached to the ripcord manually. A static line isattached to the ripcord and the aircraft or ejectionseat. When the line becomes taut, it withdrawsthe ripcord locking pins or deployment bag. Theparachute then opens.

LINE, SUSPENSION—Nylon cords thatconnect the canopy of the parachute to the harnessassembly.

LINE, TOGGLE—One or more parachutelines that run from a slot or orifice in a steerablecanopy to the harness, providing steerability.When such lines are under tension duringparachute opening or descent, they are classifiedas suspension lines.

LINE, VENT—Nylon cord that crosses thevent opening of a canopy.

LINE, WITHDIL%WAL—A line connectingthe stabilizer drogue on the ejection seat to thelocking pins and canopy vent on the NES-8B andMBEU parachute assemblies. The line opens thecontainer and withdraws the canopy duringnormal ejection operation.

LINE, CONNECTOR—A small, releasable,rectangular metal fitting used to connect the liftwebs and suspension lines.

LINK, CONNECTOR, WITHDRAWALLINE—Nylon webbing with loops sewn in bothends. The withdrawal line connector link attachesthe withdrawal line to the apex of the canopy andlarge loop in shortened anti-squid line.

LOCK, RIPCORD PIN—The ripcord pinlock is used in conjunction with the ripcord pinpull test. The lock is designed in such a manneras to allow initial movement of the ripcord pins,but does not permit them to totally disengage.

LOCKSTITCH—A common sewing-machinestitch formed when the thread in the needle goesthrough the material and connects with the bobbinthread. The needle and bobbin thread should lockin the center of the material thickness. (ReferenceFederal Standard 751, Type 301.)

LONG BAR—A long metallic or wooden barused in parachute packing and used as an aid inclosing a parachute container.

LOOP—A warp or filling thread pulled outto form a loop on a cloth surface.

LOOP, HESITATOR—One of a series ofwebbing or tape loops that holds suspension linesin an orderly position in the container when theparachute is packed, and that pays the lines outin sequence for orderly deployment of the canopyassembly.

L O O P , L O C K I N G — A l o o p s e w n t odeployment bag or canopy to allow full extensionof suspension lines before opening the canopy.

LOOP, RETAINING—Webbing or tape loopused to hold folded lines or excess webbing inposition.

LOOSE STITCHES—Thread that does not liesmoothly on the surface of the cloth.

LOX—Abbreviation for liquid oxygen.

LPM—Abbreviation for liters per minute.

LUMP—An internal imperfection of asuspension line that feels hard to the touch. It isusually caused by internal knots in core yams orcasings, or by slippage or displacement of one ormore inner core yams near an overlap.

MANUFACTURERS’ CODES—Identifica-tion codes for every manufacturer listed as

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a procurement source in accordance withcataloging handbooks H4-1 and H4-2, FederalSupply Codes for Manufacturers.

MARGIN—The space from the outer row ofstitching to the edge of the fold of cloth.

MILDEW—A damaging fungus or mold thatforms on cloth and leather. It is caused bydampness and the absence of fresh air andsunlight.

MIS-PICK—An extra or incorrectly posi-tioned filling thread.

MISSING PICK—A filling yarn (pick) whollyor partially missing.

MISSING STITCHES—A space betweenstitches in the same row in which there is nothread.

MM—Abbreviation for millimeters.

NAMEPLATE—A labe l at tached toequipment, giving data as to type, model number,date of manufacture, date placed in service, etc.The stenciled gore on a canopy is called thenameplate gore.

N E E D L E D A M A G E — W h e r e n e e d l epenetration has damaged threads in the cloth.

NOTE—An informative item. The note mayprecede or follow the step or item to which itrefers.

OVEREDGE—Stitching around the outeredge of cloth to prevent the edges from ravelingor fraying.

OVERFOLD—An excess of material causingedge of inner fold to double, wrinkle or pleat.

OVERLAP—To extend over and cover apieceof cloth.

OVERLAP, CORE—The overlapping of anincoming and outgoing suspension line inner coreline.

PACK—To put together compactly; to storeneatly; for example, the act of packing aparachute consists of stowing suspension lines andcanopy in the container assembly in such a way

as to ensure safe storage and proper opening ofthe parachute assembly.

PACK ASSEMBLY—A rigged and packedparachute. See also CONTAINER.

PACKING BOARD—A tool used to tensionsuspension lines with the anti-squid lines attachedto the connector links. Basically it consists of aboard and two large spools.

PACKING TRAY—The suspension linestowage assembly on the NES-8B parachuteassembly. It is a cloth-covered board withhesitater tubes attached. After stowage ofsuspension lines, the container is moved uparound the tray. The tray is then secured by bolts,which pass through the bottom of the container.

PAD, BACK—A pad attached to the insideof the parachute harness to provide comfort.

PALM, SEWING—A hand protector that isused when sewing.

PANEL, END SCOOP—A scoop-shapedcloth pocket attached to the bottom of the LW-3Bparachute assembly in place of an end flap.

PARACHUTE—A device that o f fersresistance to the air, thereby decreasing thevelocity of a descending body to permit landingat a suitable rate of descent.

PARACHUTE ASSEMBLY—A completeparachute, including the canopy assembly,container assembly, harness assembly, andriser/lift web assembly.

PARACHUTE, ATTACHED-TYPE—Aparachute assembly, such as T-10 or NES-15A,that has its container opening device attached tothe aircraft or ejection seat by a static line.

PARACHUTE, BACK-TYPE—A parachutethat is worn on the back to allow the wearerfreedom of movement; for example, the NB-6parachute assembly.

PARACHUTE, CARGO—A parachute usedto air drop materials such as food, water,explosives, clothing, weapons, and supplies.

PARACHUTE, CHEST-TYPE—A para-chute that is attached to D-rings on the chest-type

A I - 9

harness. It may be detached to permit morefreedom of movement.

PARACHUTE, DROGUE—An auxiliaryparachute used with any system that requires somemethod of deceleration or stabilization; forexample, an ejection seat.

PARACHUTE, FREE-TYPE—A parachuteassembly, such as NS-3, that is opened by manualor automatic pulling of a ripcord. No static lineis used with this type of parachute assembly.

PARACHUTE, PILOT—A small, spring-operated, cloth-covered auxiliary parachute thatis usually constructed on a steel wire frame andattached to the peak of the canopy. It acceleratesthe withdrawal of the canopy from the container.The pilot parachute is packed under tension andimmediately opens when released from thecontainer.

PARACHUTE, RESERVE—A chest-typeparachute attached to the harness of a trainingor test parachute in addition to the back type. Ithas no pilot parachute. It is used in case the mainparachute fails to open properly or sustains suchdamage as to cause an unsafe rate of descent.

PARACHUTE SEAT-TYPE—A free-typeparachute suspended at the rear of the wearerbetween the hips and knees. It has an attachedseat pad, together with the container, that servesas a cushion when the entire assembly is in placein the seat.

PARACHUTE, TRAINING—A combina-tion of two parachute assemblies. A main, back-type parachute and reserve, chest-type parachute,with a training harness assembly designed toaccommodate both parachutes. Its use is manda-tory on all premeditated student training jumps.

PARACHUTE, TROOP—A parachute usedby a paratrooper for a premeditated jump overa designated area.

PARACHUTIST, NAVAL—A person whohas successfully completed a prescribed course inparachute jump training.

PARAFFIN—Wax generally used with50-percent beeswax as a hot dip to prevent thefraying of cut ends of webbing, cord, and tape.See also BEESWAX.

PARARAFT—An emergency, one-man liferaft packed in a container, along with survivalequipment. The pararaft is secured to theparachute pack or seat pan.

PARATROOPER—A soldier trained andequipped to parachute into combat.

PEAK—The top center of the parachutecanopy, the point at which all vent lines cross.Also called apex or crown.

PERMEABILITY—The measured amount, incubic feet, of the flow of air through a square footof cloth in 1 minute under a specified pressure.

pH VALUE—An indication of the acidity oralkalinity of a solution. A reading of pH may bemade by the use of test strips.

PICK—A cloth filling thread, taken as a unitof fineness of cloth.

PILOT PARACHUTE FRAME—Wireframe or spring used in a type of pilot parachuteto initiate opening action of a parachute uponrelease from the container.

PIN, RIPCORD LOCKING—A small steelpin attached to a ripcord and passed through alocking cone to hold a container in a closedposition.

PIN, SLIDE DISCONNECT—A directionalfastener that connects the withdrawal line anddrogue link line on MBEU parachutes notdesigned for use with a guillotine. One portionconnects to the ejection seat and the other is ametal sleeve around the drogue link line. Depend-ing on the direction of pull, the lines will eitherremain attached or the slide disconnect pin willbe withdrawn, and the lines will separate.

PIN, TEMPORARY LOCKING—A metalpin inserted through the eye of the locking conesto hold the side flaps in place until the ripcordpin is inserted.

PLATE, ANCHOR—A narrow metal plateused on MBEU parachute assemblies. It isattached to the end of the ripcord housing andhas holes that fit over the container locking cones.When the ripcord pins are inserted in the lockingcones, the anchor plate is held in place, thusholding the ripcord housing in position.

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PLATE, LOCKING PINS—A temporarylocking pin attached to a thin, flat, rectangularmetal plate. The pin-plate arrangement is used totemporarily lock the pilot parachute while the sideflaps are being closed.

PLEAT—A fold sewn in cloth.

POCKET, DATA CARD—Small patchpocket sewn to specified parachute containers forrecord data card. (Record card used for drogueparachute assemblies only.)

P O C K E T , E L A S T I C S T O W A G E — Apocket, formed of elastic cloth, that encloses theexternal pilot parachute on the NB-11 parachuteassembly.

POCKET, RIB—A pocket made by sewinglengths of tape to a type of pilot parachute canopyto contain the four frame ribs.

POCKET, RIPCORD HANDLE—A smallpocket of cloth or elastic webbing sewn to theharness (or container assembly). It holds theripcord handle in position.

POCKETS, DEFLATION—Pockets sewn tothe canopy at the skirt hem. After landing inwater, they serve to anchor the canopy, causingthe canopy to deflate. This prevents the canopyfrom dragging the parachutist through water.

POROSITY OF A FABRIC—The measuredamount, in cubic feet, of the flow of air througha square foot of fabric in 1 minute under specifiedpressure. Also known as PERMEABILITY.

PREMATURE OPENING—Any accidentalopening of a parachute that occurs prior tointended deployment.

PRESSURE—The force exerted by liquid orgas per unit of area on the walls of a container.See also PSIG, PSIA, and ATMOSPHERICPRESSURE.

PRESSURE DROP—Loss in pressure, asfrom one end of a distribution line to the other,due to friction and other factors.

PRESSURE EXPLOSION—Explos ioncaused by rapid conversion of liquid oxygen togaseous oxygen in a confined space due toevaporation and warming.

PROTRUDING YARN (Core Casing orTread)—A condition in which either the inner coreyarns extend through the casing or where the yarnsor threads of the casing extend beyond the surfaceof the casing itself.

PSI—Abbreviation for pounds per squareinch. See also PSIA and PSIG.

PSIA—Abbreviation for pounds per squareinch, absolute. Absolute pressure is measuredfrom absolute zero (100-percent vacuum) ratherthan from normal, or atmospheric pressure. Itequals gauge pressure plus 14,696 pounds persquare inch. See a lso PSI , PSIG, andATMOSPHERIC PRESSURE.

PSIG—Abbreviation for pounds per squareinch, gauge. Indicates pressure above ambientpressure, as indicated on a pressure gauge ventedto the atmosphere. See also PSI and PSIA.

PULL UP CORDS—Nylon cords of varyinglengths used to pull up the sides and ends of thecontainer flaps over the container cover and topull the cones through the grommets. They arealso used to pull the suspension lines into placein some types of containers.

P U S H P I N — A s t r a i g h t p i n u s e d t otemporarily secure material while sewing.

PYRO BOX—The container used to storepyrotechnic devices such as flares and cartridgeswhile they are removed from the ammunitionstorage area.

PYROTECHNIC DEVICE—Any device thateither bums or explodes or uses burning orexploding to operate a system. Examples ofpyrotechnic devices are static line cutters, ballisticspreading guns, and automatic actuators.

QA—Abbreviation for quality assurance.

QUALIFIED PERSONNEL—Qualifiedpersonnel are defined as personnel who havesatisfactorily completed a prescribed course at aNavy training school, Fleet Readiness AviationMaintenance Personnel Training Program(FRAMP), Interservice/factory training, orformal or informal in-service training [refer toOPNAVINST 4790.2 (series)]. In addition, apractical demonstration of the skills acquired inany of the foregoing training situations, to the

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satisfaction of the work center supervisor/divisionofficer, is required before the designation“qualified” can be assigned.

R—Abbreviation for radius.

RATE OF DESCENT—The speed that aparachute descends through the air. The ratevaries according to atmospheric pressure, weightof load, movement of air (updraft and down-draft), and size, design, and condition ofcanopy.

RAVEL (UNRAVEL)—TO separate, untwistor unwind, leaving a frayed or ragged edge.Ravel is the preferred word to describe such acondition.

RECEIVER ASSEMBLY, AUTOMATICPARACHUTE RIPCORD RELEASE—Thatpart of the cartridge-actuated automatic ripcordrelease that houses the aneroid, sear, and hammer.

REF—Abbreviation for reference.

REFILL (In reference to oxygen cylinders)—To refill is to recharge a cylinder, regardless ofthe residual pressure remaining within thecylinder.

REINFORCEMENT—Any strengtheningmeasure that enhances the basic integrity of astructure, joint or assembly; for example, the tapeor webbing used to strengthen parts of a canopy,container, harness, etc., in a parachute assembly.See also WEBBING and REINFORCEMENT.

RELEASE ASSEMBLY, RIPCORD HOUS-ING, MANUAL—An assembly that releases theripcord housing at the top end flap when theparachute is at full suspension line stretch.

REPAIRS, MAJOR—Repairs requiringspecial equipment, personnel, or materialsnormally not available at intermediate or locallevels of maintenance.

REPAIRS, MINOR—Repairs that can beeffected at intermediate or local levels ofmaintenance.

RETAINING SLEEVE—A series of stowagetunnels.

RFI—Ready for issue.

RIG—To assemble and adjust; to equip. Forexample, the act of rigging a parachute assemblyconsists of assembling all component parts inpreparation for packing.

RING, VENT—A molded rubber ring inthe vent collar. It stretches when the airrushes into the canopy as the parachute begins toinflate.

RIPCORD—A locking device that secures thefolded parachute within the container and thateffects the release of the parachute. The ripcordconsists basically of locking pins, a flexiblecable and a handle. See also AUTOMATICPARACHUTE RIPCORD RELEASE; BALL,CABLE RETAINING; CABLE, RIPCORD;CLAMP, RIPCORD HOUSING; HANDLE,RIPCORD; HOUSING, EXTENSIBLE RIP-CORD; HOUSING, RIPCORD; IN, RIP-CORD LOCKING; POCKET, and RIPCORDHANDLE.

RIPCORD PIN RETENTION TIE—Athread of a predetermined value that is usuallysecured to a lead ripcord pin of a packedparachute. Its function is to retain a ripcord pinin its cone and prevent premature disengagementof the pin from the cone. USE ONLY ASAUTHORIZED.

RISER—The webbing that connects anintegrated torso suit or harness to the canopyassembly on parachutes. The riser is composedof two lift webs, and there are two risers on eachparachute assembly.

RUNOFF—Sewing not on a seam or cloth.

RUPTURE—One or more yarns of suspen-sion line casing being cut or severed, sometimesexposing the inner core. Occasionally, tears, cuts,or other forms of damage to the canopy aredefined as a rupture when caused by dynamic loadconditions.

SADDLE—That part of the main lift web ofthe harness that provides a seat or sling for thewearer.

SAFETY TIE—A low strength thread thatserves to indicate that an assembly has not beendamaged, tampered with, or opened since the lastregular inspection.

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SCRAP—To discard, with proper authori-zation, items, parts or materials that are obsoleteor no longer usable.

SDLM—Standard depot-level maintenance.Provides for a comprehensive inspection ofselected aircraft structures and materials, criticaldefect correction, preventive maintenance asrequired, modification and technical directivecompliance to ensure reliability and operationalavailability of the aircraft at minimum cost forthe established operating service period, and toprovide intermediate support during the totalservice life.

SDLM/CONVERSION—Standard depot-level rework concurrent with special rework, theaccomplishment of which alters the basic charac-teristics of the aircraft to such an extent as toeffect a change in any part of the modeldesignation (i.e., F-4B to F-4D). NAVAIRapproval required.

SDLM/CRASH DAMAGE—In addition toaccomplishing SDLM (standard depot-level main-tenance), repair and restoration to a serviceablecondition that part of the aircraft that hassustained damage resulting from an accident oran incident.

SDLM/MODIFICATION—Accomplishmentof standard depot-level rework concurrent witha modification that causes major work effortresulting from the installation of these technicaldirectives. NAVAIR approval required.

SEAM—A series of stitches joining two ormore pieces of cloth. For government work, thetype of seam is indicated by a symbol that givesthe class of seam, the number of stitching, andthe number of rows of stitching. (Reference Fed.Std. 751.)

SEAM, DIAGONAL—A French-fell seam ofthe canopy that joins two sections of a gore.Diagonal seams meet the centerline of the goreat angles of 450 and 135.

SEAM, ENGLISH-FELL—A seam in whichone piece of cloth is folded back upon itself, andthe other piece is a plain overlap.

SEAM, FOUR-NEEDLE FOUR-STITCH—A method of stitching that can be performed inone operation by a four-needle sewing machine.

It is used in sewing the vent hem, skirt hem, andradial seams of a canopy.

SEAM, FRENCH-FELL—A seam in whichthe cloth is folded back upon itself and stitched.

SEAM, OVERLAP—A seam in which thetwo pieces of cloth are joined by overlappingenough to accommodate one or more rows ofstitching.

SEAM, RADIAL—A seam, joining twogores, that extends radially from the vent to theskirt hem.

SEAM, TWO-NEEDLE TWO-STITCH—Aseam in one operation by a two-needle sewingmachine; for example, a diagonal seam.

SEAR—To melt or seal with heat; forexample, to sear the end of nylon webbing, oneheats the end until the nylon melts andfuses. This prevents raveling. Also, the catchthat holds the hammer of a firing mechanismcocked. The sear in an automatic parachuteripcord release is attached to the aneroid in thereceiver assembly.

SEAT PAN—A sponge-rubber-covered metalseat that is contoured for comfort to the user. Aseat pan is used with seat-type parachutes andback-type parachutes when a packaged life raftassembly is used. A high-speed seat pan hassections for support under the pilot’s thighs duringejection. This reduces leg strain caused by highacceleration loads.

SECTION—Each major part of a gore.Sections are bordered by radial seams, diagonalseams, or vent or skirt hems. In the 28-foot, flatcanopy, four sections are used in each gore(previously known as panel).

SECURITY—An item firmly, positively,and safely attached in the authorized manner.

SELVAGE—An edge of a woven fabric soformed as to prevent raveling, as compared to acut edge, which will ravel.

SELVAGE, BROKEN—Cut, broken, or tomselvage edge.

SELVAGE, STRINGY OR LOOPY—Ir-regular stringy or loopy selvage edge.

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SEPARATOR, SUSPENSION LINE—A toolused to aid in keeping suspension lines and canopyskirt in order while packing a parachute.

SERVICE LIFE—The time period duringwhich the item can be maintained in servicewithout replacement.

SERVICING PARACHUTES—Inspecting,cleaning, repairing, and repacking parachutes atperiodic (calendar) intervals. Periodic intervals forparachutes should correspond either to the aircraftcalendar inspection or to the phased maintenanceinspection cycle program, as directed byapplicable MRC or Special Inspection Card Deck.

SERVING—A method of wrapping orbinding the ends of a cord or a line so it will notravel. Sometimes referred to as “whipping.”

SEWING MACHINE—A machine with apower-driven needle, used for sewing andstitching.

SHEARS, PINKING—Shears with a saw-toothed inner edge on the blades for makingzigzag cut.

SHROUD LINE—Slang for suspension line.

SKIPPED STITCHES—Threads that are notinterlocked.

SKIRT, CANOPY—The lower edge of acanopy.

SLMIP—Suspension l ine mandatoryinspection point.

SLUB—An abruptly thickened place in clothcaused by manufacturer’s defect.

SM&R CODES—Abbreviation for source,maintenance, and recoverability codes. Comprisedof three parts; a two—position source code, a two—position maintenance code, and a one—positionrecoverability code.

SMASH—Abrasion damage that causesbroken warp and filling threads and weaveseparation.

SNAP, QUICK-CONNECTOR—A large,hook-shaped, spring-loaded snap used to attachthe chest-type parachute to the two D-rings on theharness.

SNAP, QUICK-EJECTOR—A harness snapthat attaches to the V-ring to secure two parts ofthe harness together. The ejector arm releases theV-ring when the finger-grip lever is pulledout ward.

SOCKET, AUTOMATIC PARACHUTERIPCORD RELEASE—The part o f theautomatic parachute ripcord release that engagesthe ball on the power cable. This socket is attachedto the piston by a rivet.

SPECIFIC GRAVITY—Density of fluidcompared to density of water.

SPEED LINK—Slang for connector link.

SPLICE—The joining of two strands for coreends by interweaving or mechanical joint.

SPREADER BAR—A type of tension hook,used to hold connector links in position duringparts of the packing procedure.

SPREADING GUN, BALLISTIC—A deviceattached to suspension lines just below the skirthem on the parachute assembly. Just before fullsuspension line stretch, the gun discharges and,by explosive force, spreads the skirt of the canopy.

SPRING, C O N T A I N E R O P E N I N GBANDS—Stretchable bands composed of a seriesof springs installed in a cloth case with a hookat each end. They are installed under tension onthe pack, to pull apart the end and side flaps afterthe ripcord is pulled. Also called pack openingband or bungee.

SQUIDDING—A state of incomplete canopyinflation in which the canopy has a squid- or pear-like shape.

STAND, CONTAINER—A rigid stand usedto hold some parachute containers, such as theMartin-Baker horseshoe container, during part ofthe packing procedure.

STATIC LINE CUTTER—A device used tocut the static line to free the parachutist andprevent entanglement.

STIFFENER, CONTAINER—A piece ofmetal or fiber glass or phenolic fiber placed in thecontainer to stiffen the flaps. These strips are alsoused for stiffening and shaping the bottoms ofseveral back-type containers.

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STITCH, BASEBALL—A stitch used inrepair and patching of fabrics. Refer to“Repair/Fabrication,” Chapter 4, of NAVAIR13-1-6.2

STITCH, BASTING—A long, loose stitchmade with single or double thread. Usedto temporarily hold two or more pieces ofmaterial.

STITCH, BOX—Rectangular stitch used toattach and reinforce.

STITCH, BUTTONHOLE—A reinforcedstitch made on the edge of a slit or hole. Eachindividual stitch forms a half-hitch. The distancefrom the edge, and the spacing of the stitches, isdetermined by the type of material used.

STITCH, OVERTHROW—A stitch used torepair weakened seams, to reinforce slidefasteners, and to join two pieces of materialtogether.

STITCH, ZIGZAG—A stitch made by asewing machine that stitches alternately on twoor more parallel lines; for example, it is used toreinforce and anchor the suspension lines to thecanopy. The number of stitches per inch isdetermined by counting the number of points onone side per linear inch.

STITCHES PER INCH—The number ofneedle penetrations where threads are interlaced,per linear inch.

STRIP BACK—Broken thread filament(s)wrapped around the remaining thread forming anenlarged area on cloth.

STRAP, CHEST—The harness webbing thatis secured across the chest with a snap and aV-ring to prevent the wearer from falling out ofthe harness.

STRAP, CROSS CONNECTOR—A shortlength of webbing sewn across the lift webassembly or attached between suspension lineconnector links. It prevents streaming of a canopyin the event one riser was not properly attachedto the harness.

STRAP, HORIZONTAL BACK—An adjust-able part of harness webbing extending across thesmall of the wearer’s back.

STRAP, LAP RESTRAINT—A strapattached to the integrated torso harness suit toretain the rigid seat survival kit to the wearer.Prior to ejection it serves as safety restraint forthe aircrewman.

STRAP, LEG—That part of the harnesswebbing that encircles the wearer’s leg. The legstraps are adjustable.

STRAP, PILOT PARACHUTE CONNEC-TOR—Tubular nylon webbing that joins the mainparachute and the pilot parachute.

STRAP, SHOULDER—The part of theharness webbing that crosses the wearer’s backat the shoulder blades.

STRAP, TENSION—A strap that attaches tothe peak of a canopy to keep the canopy andsuspension lines taut during parts of the packingprocedures.

STOWING—The act of putting away in aneat, orderly way. Stowing of suspension linesinvolves inserting the lines into the hesitater loopsor stowage channels in such a way as to ensureproper paying out of lines when the parachute isopened. Stowing of the canopy involves foldingand inserting the canopy into the container in sucha way as to ensure proper opening of the canopywhen the parachute is used.

SUPPORT FIXTURE—A rectangular pieceof metal used to aid in closing the LW-3Bpersonnel parachute assembly. The fixture isbolted to the container base and clamped to thepacking table.

SURVEY—A formal process by which aparachute or other accountable equipment iswithdrawn from service or removed from records.

SWAGE—To attach a device to a cable bymeans of pressure. A swaging machine compressesa fitting, causing it to grip tightly to the cable towhich it is being attached.

T-HANDLE—A handle in the shape of theletter T.

TAB, ANCHOR—A cloth loop attachedto a metal plate and used on some MBEU para-chute assemblies. It is placed over a lock-ing cone and is used to secure the withdrawal

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line slide disconnect pin in position prior tooperation.

TAB, END—An oval metal fitting securedto each flap of seat-type, Martin-Baker andchest-type parachute containers. The end tabsfit over the cones and secure the end flapsin a closed position until the locking pins arepulled.

TACK (HAND TACK)—To attach tempo-rarily prior to final sewing and to tie temporarilyas an aid in positioning. Also, to permanentlysecure portions of a parachute together; forexample, the attachment of a seat cushion to aparachute container assembly.

TACK, BUTTERFLY—The type of tackingused in securing the riser assembly to the NC-3container. See also TACK.

TAPE—A narrow woven ribbon of cotton,linen, nylon, or other material.

TAPE, FILAMENT—An adhesive tape withfiber cords in the backing. The cords are usuallyfiber glass, nylon, linen, or other high—strengthmaterial. This tape has high tensile strength alongthe lengthwise direction.

TAPE, HOOK—Strip of nylon tape withsmall nylon hooks on one side. Hook tape is usedwith pile tape as a fastener.

TAPE, PILE—A strip of nylon tape withsmall nylon loops on one side. Pile tape is usedwith hook tape as a fastener.

TAPE, SURGICAL—A white linen or cottontape with adhesive on one side. Commonly calledadhesive tape.

TEAR STRENGTH—The average force,expressed pounds, required to continue a teareither across the filling or warp of cloth.

TEMPLATE—A pattern or gauge commonlyin the form of a thin plate of cardboard, wood,or metal. It is used as a guide in the layout orcutting of flat work.

TENSILE STRENGTH—The greatest stresscloth can withstand along its length withoutrupturing, expressed as a number of pounds persquare inch (of cross section).

TERMINAL END FITTING—The end of theautomatic parachute ripcord release arming cablethat connects to the ejection seat, lap belt, or otherdesignated point. See also CABLE, ARMING,and AUTOMATIC PARACHUTE RIPCORDRELEASE.

THIN SPOT (Suspension Line)—A conditionwhereby the diameter of the suspension line asseen visually is less than other portions of thesuspension line. This condition is normally causedby broken inner cord yarn(s) or an improperoverlap.

THREAD, SEPARATION—A bunching ofthreads in cloth, leaving a hole or separation inthe cloth. A thread separation can run either withthe warp or filling of a cloth.

TIE, RIPCORD PIN RETAINING—A low-strength thread or cord used specifically to preventripcord pins from creeping and possibly causinginadvertent opening.

TIGHT STITCHES—Thread under excesstension, causing one sewing thread to lie on thesurface of the cloth or causing puckering of thecloth .

TOOL, PACK CLOSING—An aid to clos-ing the LW-3B parachute assembly container.It is used to align the grommets over lockingcones.

TORSO HARNESS SUIT—A combinationof webbing and a torso suit that includesthe parachute harness, lap belt, shoulder belt,and life vest attachment fittings. See alsoHARNESS.

TORQUE—A force or combination of forcesthat tend to produce a rotating or twisting motion.Torque is often expressed in inch-pounds orfoot-pounds. A torque wrench is used to applya measured torque.

TOTAL LIFE—Total life is the period of timecommencing with the date of manufacture thatan item may be retained in a packaged, out-of-service condition and remain acceptable forservice.

TUBE, GUIDE—A narrow tube used to guidethe vane-type pilot parachute grommet over itslocking cone.

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TWIST—Rotation of the suspension linecasing induced generally during final assembly ofthe canopy, suspension lines and connector links.

TWIST OF THREAD OR CORD—Thedirection (right or left) in which the strands ofthread or cord are wound around one another.If the thread unwinds when turning it to the left,it is right twist; if it tightens, it is left twist. Righttwist is also known as Z-twist. Left twist is alsoknown as S-twist.

TYP—Abbreviation for typical.

UNDERFOLD—Insufficient cloth foldedinside a seam. The raw edges of cloth will showwhen underfold is excessive.

UNEVEN STITCHING—Stitching wavy, ornumber or stitches varying.

UNTACK—To remove a tacking. See alsoTACKING.

V-RING—A metal fitting shaped in the formof a closed letter V. For example, V-rings, usedwith quick-ejector snap fittings, secure a harnessassembly on a wearer.

V-TAB—Webbing reinforcement at the pointwhere the suspension line enters the canopy.

VENT—The circular opening at the peak ortop of the canopy. As the parachute opens anddescends, some of the air in the canopy escapesthrough this vent, thus reducing the strain on thecanopy and steadying descent. It is about 18inches in diameter for personnel parachutes.

WARNING—Indicates danger to personnel.The warning precedes the step or item to whichit refers.

WARNING FLAG—A tag attached toan assembly, indicating that the assembly isnot operational. Often the flag is attached tosafety-pins on pyrotechnic devices to indicatenecessity of removal before operation. Also, it is

used to flag defective or incomplete equipmentto preclude use.

WARP—The threads that run parallel to theselvage edge of cloth; those that are crossed bythe filling threads.

WEAVE—To manufacture a web or cloth ona loom by interlacing the warp and filling yams.Also the particular pattern employed in weavingcloth. The cloth for parachute use is one up andone down (plain weave), two up and one down(twill weave) or ripcord.

WEAVE SEPARATION—Looseness ofweave caused by strain or poor weaving.

WEB (WEBBING)—A strong, narrow,closely-woven tape of synthetic, cotton, or linenfiber designed for bearing weight. For example,it is used in the manufacture of the parachuteharness.

WEBBING, ELASTIC—A webbing havingelastic threads to give it greater elasticity thanregular webbing. It is used in the fabrication orelastic ripcord pockets.

WEBBING, REINFORCEMENT—Shortlengths of webbing sewn to the skirt hem at thejunction points of the suspension lines and thecanopy.

WEBBING, TUBULAR—Strong synthetic ornatural fiber webbing woven in the form of a tube.

WET LOCKER—A tower or compartmentmaintained for hanging parachutes that are dampor have been immersed in water.

WHIPSTITCH—A stitch used to join twopiece of webbing and to reinforce weak seams.

WHISKER—A thread filament protrudingfrom cloth.

YOKE AND PLATE ASSEMBLY—Theremovable end of connector link.

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APPENDIX II

REFERENCES

CHAPTER ONE

Aircrew Survival Equipmentman 3 & 2, Vol 2, NAVEDTRA 10329, NavalEducation and Training Program Development Center, Pensacola, Florida,1983.1

Emergency Personnel and Drouge Parachute Systems Manual, NAVAIR13-1-6.2, Naval Air Systems Command, Washington, D.C., October 1988.

Cartridges and Cartridge Actuated Devices for Aircraft and Associated Equipment, NAVAIR 11-100-1.1, Naval Air Systems Command, Washington,D.C., January 1984.

Naval Aviation Maintenance Program (NAMP), OPNAVINST 4790.2 (Series),Office of Chief of Naval Operations, January, 1989.

CHAPTER TWO

Aircrew Survival Equipmentman 3 & 2, Vol 2, NAVEDTRA 10329, NavalEducation and Training Program Development Center, Pensacola, Florida,1983.1

Emergency Personnel and Drouge Parachute Systems Manual, NAVAIR13-1-6.2, Naval Air Systems Command, Washington, D.C., October, 1988.

Cartridges and Cartridge Actuated Devices for Aircraft and Associated Equipment, NAVAIR 11-100-1.1, Naval Air Systems Command, Washington,D.C., September 1984.

Naval Aviation Maintenance Program (NAMP), OPNAVINST 4190.2 (Series),Office of Chief of Naval Operations, January 1989.

CHAPTER THREE

Aircrew Survival Equipmentman 3 & 2, Vol 2, NAVEDTRA 10329, NavalEducation and Training Program Development Center, Pensacola, Florida,1983.1

1 Effective 1 September 1986, the Naval Education and Training Program Development Center(NETPDC) was officially changed to Naval Education and Training Program ManagementSupport Activity (NETPMSA).

AII-1

Emergency Personnel and Drouge Parachute Systems Manual, NAVAIR13-1-6.2, Naval Air Systems Command, Washington, D.C., October 1988.

CHAPTER FOUR

Aircrew Survival Equipmentman 3 & 2, Vol 1, NAVEDTRA 10328-1, NavalEducation and Training Program Management Support Activity,Pensacola, Florida, 1987.

Emergency Personnel and Drouge Parachute Systems Manual, NAVAIR13-1-6.2, Naval Air Systems Command, Washington, D.C., October 1988.

Rescue and Survival Equipment Manual, NAVAIR 13-1-6.5, Naval AirSystems Command, Washington, D.C., February 1988.

Aircrew Personal Protective Equipment Manual, NAVAIR 13-1-6.7, NavalAir Systems Command, Washington, D.C., January 1989.

NATOPS General Flight and Operational Instructions Manual, OPNAVINST3710.7 (Series), Office of Chief of Naval Operations, July 1987.

Naval Aviation Maintenance Program (NAMP), OPNAVINST 4790.2 (Series),Office of Chief of Naval Operations, January 1989.

CHAPTER FIVE

Aircrew Survival Equipmentman 3 & 2, Vol 1, NAVEDTRA 10328-1, NavalEducation and Training Program Management Support Activity,Pensacola, Florida, 1987.

Rescue and Survival Equipment Manual,Systems Command, Washington, D.C.,

CHAPTER SIX

NAVAIR 13-1-6.5, Naval AirFebruary 1988.

Aircrew Survival Equipmentman 3 & 2, Vol 2, NAVEDTRA 10329, NavalEducation and Training Program Development Center, Pensacola, Florida,1983. 2

lnflatable Survival Equipment Manual, NAVAIR 13-1-6.1, Naval Air SystemsCommand, Washington, D.C., January 1989.

CHAPTER SEVEN

Aircrew Survival Equipmentman 3 & 2, Vol 2, NAVEDTRA 10329, NavalEducation and Training Program Development Center, Pensacola, Florida,1983.2

2Effective 1 September 1986, the Naval Education and Training Program Development Center(NETPDC) was officially changed to Naval Education and Training Program ManagementSupport Activity (NETPMSA).

A I I - 2

Aviation Crew Systems Seat Survival Kits Manual, NAVAIR 13-1-6.3, NavalAir Systems Command, Washington, D.C., January 1989.

CHAPTER EIGHT

Aircrew Survival Equipmentman 3 & 2, Vol 1, NAVEDTRA 10328-1, NavalEducation and Training Program Management Support Activity,Pensacola, Florida, 1987.

CHAPTER NINE

Aircrew Surviva! Equipmentman 3 & 2, Vol 1, NAVEDTRA 10328-1, NavalEducation and Training Program Management Support Activity,Pensacola, Florida, 1987.

CHAPTER TEN

Aircrew Survival Equipmentman 3 & 2, Vol 1, NAVEDTRA 10328-1, NavalEducation and Training Program Management Support Activity,Pensacola, Florida, 1987.

CHAPTER ELEVEN

Aircrew Survival Equipmentman 3 & 2, VOl 2, NAVEDTRA 10329, NavalEducation and Training Program Development Center, Pensacola, Florida,1983.3

Oxygen Equipment Manual, NAVAIR 13-1-6.4, Naval Air Systems Command,Washington, D.C., December 1988.

CHAPTER TWELVE

Aircrew Survival Equipmentman 3 & 2, Vol 2, NAVEDTRA 10329, NavalEducation and Training Program Development Center, Pensacola, Florida,1983. 3

Oxygen Equipment Manual, NAVAIR 13-1-6.4, Naval Air Systems Command,Washington, D.C., December 1988.

3Effective 1 September 1986, the Naval Education and Training Program Development Center(NETPDC) was officially changed to Naval Education and Training Program ManagementSupport Activity (NETPMSA).

AII-3

INDEX

A

Acceptance/special/daily inspections, 12-8 to12-9

Adapters, harness hardware, 1-12Aircraft panel-mounted regulators, 12-6 to

12-18acceptance/special/daily inspections, 12-8

to 12-9calendar/phased/SDLM inspections, 12-9

to 12-18maintenance, 12-7turnaround/preflight/postflight/transfer

inspections, 12-7 to 12-8Aircrew personal protective equipment, 4-1 to

4-32anti-g garments, 4-12 to 4-15

CSU-15/P anti-g garment, 4-13 to4-14

fitting the CSU-15/P anti-ggarment, 4-13

inspections, 4-14installing the CSU-15/P anti-g

garment hose, 4-14maintenance, 4-15

helmets, 4-18helmet configuration buildup, 4-21inspections, 4-23

calendar inspection, 4-23functional check, 4-23visual inspection, 4-23

maintenance, 4-21 to 4-22addition of reflective tape, 4-22cleaning, 4-22

major helmet assemblies, 4-19 to4-20

major helmet components, 4-20 to4-21

sizing the PRK-37/P, 4-21SPH-3C helmet, 4-23 to 4-24

fitting, 4-24maintenance procedures, 4-24

Aircrew personal protective equipment—Continued

integrated torso harnesses, 4-15 to 4-18fitting, 4-16 to 4-17

inspections, 4-18lap belt shoulder adjustments, 4-17

sizing, 4-16

maintenance scheduling and records, 4-1to 4-3

maintenance documents, 4-1 to 4-3aircrew personal protective

equipment history card, 4-2

Aircrew Personal ProtectiveEquipment Manual, NAVAIR13-1-6.7, 4-3

history card-aviation crewsystems, 4-2

maintenance data collectionsystem forms, 4-2

shop process cards (SPC), 4-2modifications of flight equipment,

4-3

oxygen masks, 4-24 to 4-32attachment of bayonet and

mechanism, 4-28 to 4-31adjustment of bayonet

4-31

fitting, 4-29 to 4-30

maintenance, 4-31

receiver

receivers,

preflight/postflight inspection, 4-31to 4-32

calendar inspection, 4-31cleaning mask, 4-31 to 4-32

pressure-demand oxygen maskMBU-12/P, 4-24 to 4-28

combination inhalation/exhala-tion valve, 4-26

sizing, 4-26 to 4-28

INDEX-1

Aircrew personal protective equipment—Continued

types of flight clothing, 4-3 to 4-12antiexposure assemblies, 4-6 to 4-12

A/P22P-6(V)2 and A/P22P-6A(V)2 antiexposure assemblies,4-8 to 4-12

fire-resistant flyer’s gloves, GS/FRP-2,4-4 to 4-5

configuration, 4-4 to 4-5fitting, 4-5maintenance, 4-5

flyer’s boot, 4-5configuration, 4-5 to 4-6fitting, 4-6maintenance, 4-6

summer flyer’s coverall CWU-27/Pand blue flyer’s coverall CWU-73/P,4-3 to 4-4

configuration, 4-4fitting, 4-4maintenance, 4-4

SV-2 survival vest, 4-6configuration, 4-6fittings, 4-6

AN/PRC-63 radio set, 5-5 to 5-7AN/PRC-90 radio set, 5-7 to 5-10AN/PRT-5 transmitting set, 5-11 to 5-12Automatic opening devices, 2-1 to 2-15

automatic parachute actuators, 2-1 to 2-9arming and assembling the automatic

parachute ripcord release, 2-7 to2-8 .

automatic parachute ripcord releasetest set, 2-5 to 2-6

checkout of armed ripcord release,2-8 to 2-9

disarming, 2-3firing altitude check, 2-5function, 2-2inspection, 2-4 to 2-5maintenance, 2-3preparation for use, 2-2ripCord release test procedure, 2-6 to

2-7ballistic spreading gun assembly, 2-9 to

2-15ballistic spreading gun cartridge

replacement and pull-force check,2-12 to 2-15

description, 2-10 to 2-11identification and handling, 2-11

log entries, 2-11safety precautions, 2-11service life, 2-11

Automatic opening devices—Continuedballistic spreading gun assembly—

Continuedoperation, 2-11removal of ballistic spreading gun,

2-12Automatic parachute ripcord release assembly,

installation of, 3-10 to 3-11Awl, hand tool, 10-12

B

Ballistic spreading gun assembly, 2-9 to 2-15Ballistic spreading gun inspection, 1-28Beacon set radio, AN/URT-33A, 5-10 to 5-11Bell jar, 11-14 to 11-15Binder’s knot, 10-29Bowline knot, 10-29

C

Cable grip, 5-21 to 5-22Calendar inspection, 12-26 to 12-33

bench test, 12-27capacitance test (empty), 12-28capacitance test (full), 12-30 to 12-31converter assembly purge, 12-27 to 12-28converter charge, 12-32 to 12-33converter leakage test, 12-29 to 12-30evaporation loss test (buildup and supply

mode), 12-31evaporation loss test (vented mode), 12-31

to 12-32fill and buildup time test, 12-30flow test, 12-32insulation resistance test (empty), 12-28relief valve test, 12-28 to 12-29service life, 12-27visual inspection, 12-27

Calendar/phased/SDLM inspections, 12-9 to12-18

bench test, 12-9inward leakage test, 12-9 to 12-18service life, 12-9

Canopies, 1-6 to 1-10Canopy damage charts, parachutes, 1-21 to

1-22Carbon dioxide, 8-1 to 8-5

CO 2 recharge equipment, 8-1 to 8-2CO 2 supply cylinders, 8-2

INDEX-2

Carbon dioxide—Continuedinspecting C02 cylinders and recharging,

8-2 to 8-5maintenance for the C-O-TWO transfer

unit, 8-5maintenance of the Walter Kidde transfer

unit, 8-5Class 111 sewing machines, 9-18Clothing, types of flight, 4-3 to 4-12Clove hitch knot, 10-30Components of parachutes, 1-5 to 1-11Configuration and function, 12-18 to 12-21Connector link ties, installation of, 3-12 to

3-13Consew 99R and 99R-3 sewing machines, 9-34

to 9-39Containers, parachute, 1-10Converter supply connection, NIP-6, 11-15 to

11-16Converter test stands, liquid oxygen, 11-13 to

11-21CSU-15/P anti-g garment, 4-13 to 4-14Curtain fastener, 10-15CWU-27/P, summer flyer’s coverall and

CWU-73/P blue flyer’s coverall, 4-3 to 4-4

D

Daily/preflight inspection, 12-2 to 12-6bench test, 12-3 to 12-6calendar inspection, 12-2special inspections, 12-2visual inspection, 12-2 to 12-3

Demonstrating the use of rafts, 6-16 to 6-19boarding the raft, 6-18safety precautions in boarding rafts, 6-18

to 6-19Differential pressure gauge, DF-1, 11-15Distress light (SDU-5/E), 5-3Dye marker, 5-1

E

Engineering requirements for fabrics, 10-6 to10-9

External pilot parachute, 3-6 to 3-7

F

Fabrication and manufacture, 10-1 to 10-30hardware, 10-12 to 10-20

curtain fastener, 10-15glove fasteners, 10-13 to 10-14

hand installation, 10-14press installation, 10-14

grommets, 10-12 to 10-13grommet press installation 10-13grommet set installation, 10-13

interlocking slide fasteners, 10-15 to10-20

fabrication, 10-18 to 10-19interlocking slide fastener

construction, 10-16interlocking slide fastener

operation, 10-16 to 10-17interlocking slide fastener tools,

10-17interlocking slide fastener repair,

10-17 to 10-18installing an interlocking slide

fastener, 10-18procurement of slide fasteners,

10-19 to 10-20shortening an interlocking slide

fastener, 10-18slide fastener pressure foot,

10-18three-way locking fasteners, 10-14three-way locking snaps, 10-14 to

10-15seams and knots, 10-20 to 10-30

hand-sewn seams, 10-20 to 10-24hand sewing the running stitch,

10-22hand-sewn overthrow stitch,

10-22 to 10-23purposes and characteristics of

the basting stitch, 10-22sewing the baseball stitch, 10-23

to 10-24use of the hand-sewn hidden

stitch and the needle used,10-24

knots, 10-28 to 10-30binders knot, 10-29bowline, 10-29clove hitch, 10-30half hitch, 10-29 to 10-30overhand knot, 10-28

INDEX-3

Fabrication and manufacture—Continuedseams and knots—Continued

knots—Continuedsquare knot, 10-29surgeon’s knot, 10-29

machine-sewn seams, 10-24 to 10-28advantages and characteristics of

a machine-sewn seam, 10-25appropriate spacing of machine-

sewn seams, 10-27 to 10-28meanings and symbols of

machine-sewn basic stitches,10-25 to 10-26

uses of varying classes ofmachine-sewn seams andstitchings, 10-26 to 10-27

special hand tools, 10-9 to 10-12awl, 10-12foot-operated grommet press, 10-10hand press, 10-10knife, 10-10, 10-11measuring devices, 10-11 to 10-12sailmaker’s palm, 10-12shears, 10-9 to 10-10star punch, 10-12

textile materials, terms, and meanings,10-1 to 10-9

construction features and uses ofvarious textile materials, 10-2 to10-4

cotton, 10-3duck, 10-3leather, 10-4NOMEX fabric, 10-3nylon, 10-3rubber, 10-3vinyl, 10-4

difference between threads andcords, 10-4 to 10-5

cords, 10-5threads, 10-4 to 10-5

engineering requirements for fabrics,10-6 to 10-9

air permeability, 10-6elasticity (or elastic recovery),

10-7 to 10-8elongation, 10-7moisture regain, 10-8resistance to abrasion, 10-8resistance to chemicals, 10-8 to

10-9resistance to heat, 10-8resistance to mildew and insects,

10-8resistance to sunlight, 10-8

Fabrication and manufacture—Continuedtextile materials, terms, and meanings—

Continuedengineering requirements for fabrics—

Continuedstrength, 10-6weight, 10-8

fiber and filament, 10-1 to 10-2bias, 10-2cloth weight, 10-2filling, 10-2selvage and raw edges, 10-2staple, 10-1tensile strength, 10-2warp, 10-2weave, 10-2yarn, 10-1

storage of textile materials, 10-5to 10-6

webbings and tapes, 10-4tapes, 10-4webbings, 10-4

Fire-resistant flyer’s gloves, GS/FRP-2, 4-4 to4-5

Flight clothing, types of, 4-3 to 4-12Flyer’s boot, 4-5Forest penetrator and flotation collar, 5-15 to

5-17

G

Garments, anti-g, 4-12 to 4-15CSU-15/P anti-g garments, 4-13 to 4-14maintenance, 4-15

Gauges and indicators, 11-7 to 11-8General packet, 5-4Glossary, AI-1 to AI-17Glove fasteners, 10-13 to 10-14

hand installation, 10-14press installation, 10-14

Grommet press, foot-operated, 10-10Grommets, 10-12 to 10-13

grommet press installation, 10-13grommnet set installation, 10-13

GS/FRP-2, fire-resistant flyer’s gloves, 4-4 to4-5

H

Half hitch knot, 10-29 to 10-30Hand press, 10-10

INDEX 4

Hand-sewn seams, 10-20 to 10-24Hardware, 10-12 to 10-20

curtain fastener, 10-15glove fasteners, 10-13 to 10-14grommets, 10-12 to 10-13interlocking slide fasteners, 10-15 to 10-20three-way locking fasteners, 10-14three-way locking snaps, 10-14 to 10-15

Harness hardware, 1-11 to 1-13adapters, 1-12connector links, 1-13Koch release adapters, 1-13snaps, 1-12 to 1-13

Harness, parachute, 1-10Helicopter rescue devices, 5-12 to 5-24Helmets, 4-18 to 4-24

helmet configuration buildup, 4-21inspections, 4-23maintenance, 4-21 to 4-22major helmet assemblies, 4-19 to 4-20major helmet components, 4-20 to 4-21sizing the PRK-37/P, 4-21SPH-3C helmet, 4-23 to 4-24

Hydrostatic test of CO2 cylinders, 6-4 to 6-5Hypoxia, effects of, 11-2

I

Illumination signal kit, Mk 79, Mod 0 5-2Inflatable survival equipment, 6-1 to 6-35

demonstrating the use of rafts, 6-16 to6-19

boarding the raft, 6-18safety precautions in boarding rafts,

6-18 to 6-19inspections, 6-1 to 6-5

cleaning, 6-4determination of repairability, 6-2functional test, 6-2 to 6-3hydrostatic test of C02 cylinders,

6-4 to 6-5leakage testing, 6-3 to 6-4pull cable proof load test for

multiplace rafts, 6-3life preserver inspections, 6-28 to

6-35functional testing, 6-30inflation assembly inspection, 6-33 to6-35

battery replacement, LPU-23/P(series) and LPU-24/P (series),6-35

Inflatable survival equipment—Continuedlife preserver inspections—Continued

inflation assembly inspection—Continued

installation of cylinders: LPA-1/1A(series), LPA-2 (series),LPU-21/P (series), LPU-30/P,and LPP-1 (series), 6-34

installation of cylinders, LPU-23/P(series) and LPU-24/P (series),6-34 to 6-35

leakage test, 6-30 to 6-32test fixture, 6-30test procedure, 6-30 to 6-32

visual inspection, 6-32 to 6-33battery visual inspection,

LPU-23/P (series) andLPU-24/P (series), 6-32

battery voltage testing, LPU-23/P(series) and LPU-24/P (series),6-32 to 6-33

life preservers, 6-22 to 6-28LPP-1/1A life preserver assembly,

6-26LPU-21/P series life preserver

assembly, 6-22 to 6-24LPU-23/P series life preserver

assembly, 6-24 to 6-26LPU-24/P series life preserver

assembly, 6-26LPU-30/P life preserver assembly,

6-26 to 6-28LRU-12/A life raft assembly, 6-8 to 6-10LRU-13/A life raft assembly, 6-10 to

6-13equipment and survival items, 6-10packing procedures remote or local

pull, 6-10 to 6-13LRU-14 series life raft assembly, 6-13 to

6-15equipment and survival items, 6-14

to 6-15operation, 6-15

LRU-15/A life raft assembly, 6-15 to6-16

emergency repairs, 6-16equipment and survival items, 6-16

multiplace rafts, 6-5 to 6-8bulkheads, 6-6combination supply pocket and

bailer, 6-7inflatable seats, 6-6lifeline, 6-7righting handles, 6-7

INDEX-5

Inflatable survival equipment—Continuedmultiplace rafts—Continued

seam tapes and patches, 6-5 to 6-6supply pocket, 6-6 to 6-7topping-off valves, 6-7 to 6-8

one-man life rafts, 6-19 to 6-22LR-1 life raft assembly, 6-20 to 6-22

ballast bags, 6-21boarding handles, 6-21flotation tube, 6-20inspection, 6-22oral inflation tube, 6-20 to 6-21retaining line, 6-21sea anchor, 6-21sea anchor pocket, 6-21securing line, 6-21survival items, 6-21 to 6-22weathershield, 6-21

LRU-7/P life raft assembly, 6-19 to6-20

Inspection, daily/preflight, 12-2 to 12-6bench test, 12-3 to 12-6calendar inspections, 12-2special inspections, 12-2visual inspection, 12-2 to 12-3

Inspections, 7-3 to 7-9acceptance/phased/SDLM inspections,

7-4 to 7-8functional check, 7-7 to 7-8swaged ball pull test, 7-4 to 7-7visual inspection, 7-4

purging and charging emergency oxygensystems, 7-8 to 7-9

Inspections, personnel parachute, 1-14 to 1-16inspection schedules, 1-16parachute maintenance, 1-16reasons for inspecting parachutes, 1-14 to

1-16specifications, 1-16

Inspections, procedures for preliminary tests,1-24 to 1-30

Integrated torso harnesses, 4-15 to 4-18Interlocking slide fasteners, 10-15 to 10-20

K

Kit, seat survival, 7-1 to 7-9Knife, hand tool, 10-10 to 10-11Knots, 10-28 to 10-30

binder’s knot, 10-29bowline, 10-29clove hitch, 10-30half hitch, 10-29 to 10-30overhand know, 10-28

Knots—Continuedsquare knot, 10-29surgeon’s knot, 10-29

Koch release adapters, harness hardware, 1-13

L

Life preservers, 6-22 to 6-35Lifeline, rafts, 6-7Linear flow elements, 11-16Liquid oxygen converters, 12-18Liquid oxygen quantity gauge capacitor-type

tester, 11-16LPP-1/1A life preserver assembly, 6-26LPU-21/P series life preserver assembly, 6-22

to 6-24LPU-23/P series life preserver assembly, 6-24

to 6-26LPU-24/P series life preserver assembly, 6-26LPU-30/P life preserver assembly, 6-26 to

6-28LR-1 life raft assembly, 6-20 to 6-22LRU-7/P life raft assembly, 6-19 to 6-20LRU-12/A life raft assembly, 6-8 to 6-10LRU-13/A life raft assembly, 6-10 to 6-13

equipment and survival items, 6-10packing procedures remote or local pull,

6-10 to 6-13LRU-14 series life raft assembly, 6-13 to 6-15

equipment and survival items, 6-14 to6-15

operation, 6-15LRU-15/A life raft assembly, 6-15 to 6-16

emergency repairs, 6-16equipment and survival items, 6-16

M

Machine-sewn seams, 10-24 to 10-28Maintenance, 12-24 to 12-26

acceptance/turnaround/daily/preflight/postflight and transfer inspections,12-24

functional test, 12-25 to 12-26visual inspection, 12-25

Maintenance records and inspection parachute,1-16 to 1-22

Maintenance scheduling and records, 4-1 to4-3

maintenance documents, 4-1 to 4-3modifications of flight equipment, 4-3

Manometer preparation, 11-10Medical packet, 5-3

INDEX-6

Mirror, signaling, 5-1 to 5-2Mk 13, Mod 0 signal flare, 5-2 to 5-3Mk 79, Mod 0 illumination signal kit, 5-2Multiplace rafts, pull cable proof load test,

6-3

N

NAMP, Naval Aviation Maintenance Programforms, 1-22

NES-12 personnel parachute system, 3-1 to3-15

rigging, 3-4 to 3-15attachment of container assembly to

riser assembly, 3-12attachment of firing lanyard to

suspension line connector link,3-14 to 3-15

external pilot parachute, 3-6 to 3-7installation of automatic parachute

ripcord release assembly, 3-10 to3-11

installation of connector link ties,3-12 to 3-13

installation of release assemblylanyard and ripcord assembly, 3-13to 3-14

installation of spreading gun, 3-4 to3-6

preliminary procedures, 3-4stowage of firing lanyard into

extractor sleeve, 3-8 to 3-10straightening canopy gores with

spreader gun installed, 3-8suspension line continuity check

with spreading gun installed, 3-7 to3-8

Net, rescue, 5-17 to 5-18

0

One-man life rafts, 6-19 to 6-22LR-1 life raft assembly, 6-20 to 6-22LRU-7/P life raft assembly, 6-19 to 6-20

OPNAV 4790/38, preflight/daily/turnaround/postflight maintenance record, 1-17

OPNAV 4790/101, parachute configuration,inspection and history record, 1-17 to 1-27

Oscillating type sewing machines, 9-3 to 9-18

Overhand knot, 10-28Oxygen components test stands, 11-1 to 11-21

liquid oxygen converter test stands, 11-13to 11-21

cleaning, 11-21functions, 11-14 to 11-16

bell jar, 11-14 to 11-15converter supply connection,

NIP-6, 11-15 to 11-16differential pressure gauge,

DF-1, 11-15flow of oxygen, 11-16linear flow elements, 11-16liquid oxygen quantity gauge

capacitor-type tester, 11-16relief valve, RV-11, 11-15

maintenance, 11-16 to 11-21installation, 11-18test stand leakage tests, 11-18visual inspection, 11-18

periodic inspections, 11-21troubleshooting, 11-21

maintenance, 11-10 to 11-13manometer preparation, 11-10periodic inspections, 11-12 to 11-13

altitude chamber and suitsimulator tank inward leakagetest, 11-12

biweekly inspection, 11-13daily inspection, 11-12monthly inspection, 11-13weekly inspection, 11-12

pressure/leakage tests, 11-10leakage control valve(E) and

leakage on/off valve (G) tests,11-11

outward leakage test (regulatedhigh-pressure system), 11-11

outward leakage test (regulatedlow-pressure system), 11-11

outward leakage test (supplysystem), 11-11

suit simulator system leakagetests, 11-11 to 11-12

Vol-O-Flo calibration, 11-13Vol-O-Flo element cleaning, 11-13

oxygen, 11-1 to 11-3characteristics of oxygen, 11-2 to

11-3effects of hypoxia, 11-2types of oxygen, 11-3

INDEX-7

Oxygen components test stands—Continuedoxygen component test stand 1172AS100,

11-3 to 11-10check valve connections, 11-9control valves, 11-6 to 11-7

measuring control valves, 11-6to 11-7

nonmeasuring control valves,11-7

gauges and indicators, 11-7 to 11-8on/off valves, 11-4regulators, 11-7safety precautions, 11-10selector valves, 11-4shufoff valves, 11-7test stand connections, 11-8vacuum pump, 11-9 to 11-10Vol-O-Flo elements, 11-4 to 11-6

Oxygen masks, 4-24 to 4-32attachment of bayonet and receiver

mechanism, 4-28 to 4-31preflight/postflight inspection, 4-31 to

4-32pressure-demand oxygen mask MBU-12/P,

4-24 to 4-28Oxygen-related components, 12-1 to 12-33

aircraft panel-mounted regulators, 12-6 to12-18

acceptance/special/daily inspections,12-8 to 12-9

calendar/phased/SDLM inspections,12-9 to 12-18

bench test, 12-9inward leakage test, 12-9 to

12-18service life, 12-9

maintenance, 12-7turnaround/preflight/postflight/

transfer inspections, 12-7 to 12-8calendar inspection, 12-26 to 12-33

bench test, 12-27capacitance test (empty), 12-28capacitance test (full), 12-30 to 12-31converter assembly purge, 12-27 to

12-28converter charge, 12-32 to 12-33converter leakage text, 12-29 to 12-30evaporation loss test (buildup and

supply mode), 12-31evaporation loss test (vented mode),

12-31 to 12-32fill and buildup time test, 12-30flow test, 12-32insulation resistance test (empty),12-28

Oxygen related components—Continuedcalendar inspection—Continued

relief valve test, 12-28 to 12-29service life, 12-27visual inspection, 12-27

configuration and function, 12-18 to12-21

daily/preflight inspection, 12-2 to 12-6bench test, 12-3 to 12-6calendar inspection, 12-2special inspections, 12-2visual inspection, 12-2 to 12-3

liquid oxygen converters, 12-18maintenance, 12-24 to 12-26

acceptance/turnaround/daily/pre-flight/postflight and transferinspections, 12-24

functional test, 12-25 to 12-26visual inspection, 12-25

performance testing, 12-21 to 12-24converter charge, 12-24converter leakage, 12-24fill and buildup time, 12-24flow, 12-24performance test sheet preparation,

12-23 to 12-24relief valve, 12-24

P

Parachute actuators, automatic, 2-1 to 2-9Performance testing, 12-21 to 12-24

converter charge, 12-24converter leakage, 12-24fill and buildup time, 12-24flow, 12-24relief valve, 12-24

Personnel parachute familiarization, 1-1 to1-30

compliance with current directives, 1-30components of parachutes, 1-5 to 1-11

canopies, 1-6 to 1-10parachute containers, 1-10parachute harness, 1-10pilot chute, 1-5 to 1-6ripcords, 1-11suspension lines, 1-10

harness hardware, 1-11 to 1-13adapters, 1-12connector links, 1-13Koch release adapters, 1-13snaps, 1-12 to 1-13

INDEX-8

Personnel parachute familiarization—Continued

harness hardward—Continuedinspections, 1-22 to 1-24acceptance (original issue) calendar/

phased/conditional inspections,1-22 to 1-24

aircraft accident report inspec-tion, 1-23 to 1-24

calendar/phased, 1-23conditional inspection, 1-23original issue/acceptance, 1-23postcombat inspection, 1-23

daily inspection, 1-22special inspection, 1-22

parachute inspection and maintenancerecords, 1-16 to 1-22

canopy damage charts, 1-21 to 1-22Naval Aviation Maintenance Program

forms, 1-22parachute configuration, inspection

and history record (OPNAV4790/101), 1-17 to 1-21

cartridges and cartridge-actuateddevices, 1-19

configuration verification (a listof each item that has a servicelife), 1-19 to 1-20

initiation, 1-19miscellaneous history, 1-19procedures, 1-20 to 1-21technical directives, 1-19

preflight/daily/turnaround/postflightmaintenance record (OPNAV4790/38), 1-17

recording modifications, 1-22personnel parachute inspections, 1-14 to

1-16inspection schedules, 1-16parachute maintenance, 1-16reasons for inspecting parachutes,

1-14 to 1-16specifications, 1-16

procedures for preliminary tests andinspections, 1-24 to 1-30

ballistic spreading gun inspection,1-28

canopy inspection, 1-25 to 1-26connector link inspection, 1-27 to

1-28container assembly inspection, 1-29

to 1-30

Personnel parachute familiarization—Continued

procedures for preliminary tests andinspections—Continued

contamination inspection, 1-24 to1-25

acid and alkaline contamination,1-25

other contaminations, 1-25harness/riser assembly inspection

1-28harness/riser assembly inspection,

1-28cross-connector strap inspection,

1-29hardware inspection, 1-28 to

1-29inspecting for wear and physical

defects, 1-25pilot parachute inspection, 1-25replacement of parachute assemblies

and subassemblies, 1-24ripcord assembly inspection, 1-29

ripcord handle clip inspection,1-29

ripcord handle pocket inspection,1-29

ripcord pull test, 1-24service life checks, 1-24 .suspension and vent line inspection,

1-26 to 1-27transporting parachutes, 1-13 to 1-14

shipping-containers, 1-13 to 1-14storing, 1-14

Pneumatic rescue hand tool, 5-22 to 5-24Preservers, life, 6-22 to 6-35Pressure/leakage tests, 11-10Pull cable proof load test for multiplace

rafts, 6-3Purging and charging emergency oxygen

systems, 7-8 to 7-9

R

Rafts, multiplace, 6-5 to 6-8bulkheads, 6-6combination supply pocket and bailer,

6-7inflatable seats, 6-6lifeline, 6-7right handles, 6-7seam tapes and patches, 6-5 to 6-6supply pocket, 6-6 to 6-7topping-off valves, 6-7 to 6-8

INDEX-9

Rations, 5-4 Rescue and survival equipment—ContinuedReferences, AII-1 to AII-3Release assembly lanyard and ripcord

assembly, installation of, 3-13 to 3-14Relief valve, RV-11, 11-15Rescue and survival equipment, 5-1 to 5-24

canned drinking water, 5-4 to 5-5helicopter rescue devices, 5-12 to 5-24

cable grip, 5-21 to 5-22calendar inspection, 5-22cleaning, 5-22maintenance, 5-22

forest penetrator and flotation collar,5-15 to 5-17

cleaning, 5-16 to 5-17inspection, 5-16maintenance, 5-16

hoist quick-splice plate, 5-21calendar inspection, 5-21cleaning, 5-21maintenance, 5-21

pneumatic rescue hand tool, 5-22 to5-24

calendar inspection, 5-23 to 5-24cleaning, 5-24maintenance, 5-23

rescue harness, 5-18 to 5-20calendar inspection, 5-18 to 5-20cleaning, 5-20maintenance, 5-18preflight inspection, 5-18

rescue hook, 5-20 to 5-21calendar inspection, 5-21cleaning, 5-21maintenance, 5-20

rescue net, 5-17 to 5-18cleaning, 5-18inspection, 5-18maintenance, 5-18

rescue seat, 5-14, to 5-15cleaning, 5-15inspection, 5-15maintenance, 5-15

survivor’s sling, 5-13 to 5-14calendar inspections, 5-14maintenance, 5-14

individual aircrewman’s survival kit(SRU-31/P), 5-3 to 5-4

general packet, 5-4inspection, 5-4medical packet, 5-3

rations, 5-4signaling equipment and devices, 5-1 to

5-3distress light (SDU-5/E), 5-3

dye marker, 5-1Mk 13 Mod 0 signal flare, 5-2 to 5-3Mk 79, Mod 0 illumination signal

kit, 5-2signaling mirror, 5-1 to 5-2

survival radios and beacons, 5-5 to 5-12AN/PRC-63 radio set, 5-5 to 5-7

battery replacement, 5-7function and use of operating

controls, 5-6general principles of operation,

5-5 to 5-6inspections, 5-7

AN/PRC-90 radio set, 5-7 to 5-10batteries, 5-8operating procedure, 5-8 to 5-10

AN/PRT-5 transmitting set, 5-11 to5-12

AN/URT-33A beacon set radio, 5-10to 5-11

Rigging, parachute, 3-4 to 3-15Ripcord pull test, 1-24Ripcords, parachute, 1-11Rotary sewing machines, 9-18 to 9-39RSSK-8 series seat survival kit, 7-1 to 7-3

S

Safety precautions, 11-10Sailmaker’s palm, hand tool, 10-12SDU-5/E, distress light, 5-3Seams and knots, 10-20 to 10-30

hand-sewn seams, 10-20 to 10-24knots 10-28, to 10-30machine-sewn seams, 10-24 to 10-28

Seat, rescue, 5-14 to 5-15Seat survival kit, 7-1 to 7-9

inspections, 7-3 to 7-9acceptance/phased/SDLM inspections,

7-4 to 7-8functional check, 7-7 to 7-8swaged ball pull test, 7-4 to 7-7visual inspection, 7-4

purging and charging emergencyoxygen systems, 7-8 to 7-9

RSSK-8 series seat survival kit, 7-1 to 7-3Seats, inflatable, 6-6

INDEX-10

Sewing machines, 9-1 to 9-39oscillating type sewing machines, 9-3 to

9-18Singer sewing machine 7-33, 9-13 to

9-18lubrication, 9-14modification of presser foot for

webbing sewing, 9-17 to 9-18needles and thread, 9-14preparing the sewing, 9-17regulating the length of stitch,

9-17regulating the pressure on the

material, 9-17regulating the tension, 9-16 to

9-17removing the bobbin, 9-16removing the work, 9-17replacing the bobbin and

threading the shuttle, 9-16setting the needle, 9-15threading the machine, 9-15 to

9-16winding the bobbin, 9-16

Singer sewing machine 31-15, 9-3 to9-13

adjusting the feed dog, 9-8adjusting the thread take-up

spring, 9-8 to 9-13commencing to sew, 9-12lubrication, 9-4preparing for sewing, 9-12regulating the length of a stitch,

9-13regulating the pressure on the

material, 9-13regulating the tension, 9-12 to

9-13removing the bobbin case, 9-10removing work, 9-13replacing the bobbin case, 9-12replacing the needle, 9-8 to 9-9threading the bobbin case, 9-11

to 9-12threading the machine, 9-10timing the 31-15, 9-4 to 9-6timing the feed dog with the

needle, 9-6 to 9-7timing the needle with the shuttle,

9-6winding the bobbin, 9-10 to 9-11

rotary sewing machines, 9-18 to 9-39class 111 sewing machines, 9-18Consew 99R and 99R-3 sewing

machine, 9-34 to 9-39adjusting the bobbin thread

tension, 9-35adjustment of the thread take-up

spring, 9-39centering the needle in the throat

(needle) plate, 9-37preparing the machine for rope

stitching (model 99R-3 only),9-36 to 9-37

regulating the tension, 9-35regulating the pressure of the

presser foot, 9-35setting the needle bar at the

correct height, 9-37stitch regulator and reverse

sewing and tacking, 9-36straight and zigzag sewing, 9-36threading the 99R and 99R-3

machines, 9-34 to 9-35timing the feeding mechanism,

9-38 to 9-39timing the movement of the

needle bar frame, 9-39timing the sewing hook, 9-37 to

9-38to raise or lower the feed dog,

9-39to remove and replace and the

sewing hook, 9-38different models of the 111 W sewing

machine, 9-18 and 9-19111 W 150 sewing machine, 9-18

to 9-19111 W 151 sewing machine, 9-19111 W 152 sewing machine, 9-19111 W 153 sewing machine, 9-19111 W 154 sewing machine, 9-19111 W 155 sewing machine, 9-19

functional features, 9-19 to 9-26lubrication of the class 111

sewing machine, 9-22 to 9-23needles and thread, 9-23 to 9-24operation, 9-24preparing for sewing, 9-25removing the bobbin, 9-24removing the work, 9-25 to 9-26regulating the length of stitch,

9-25regulating the pressure on the

material, 9-25regulating the tension, 9-25

INDEX-11

Sewing machines—Continuedrotary sewing machines—Continued

functional features—Continuedreplacing the bobbin and

threading the bobbin case,9-25

setting the needle, 9-24threading the machine, 9-24timing the 111 W class sewing

machines, 9-21 to 9-22winding the bobbin, 9-25

Singer sewing machine 143 W 2 and3, 9-30 to 9-33

bobbin and bobbin case, 9-31needle and thread, 9-30raising or lowering the feed dog,

9-33regulating the length of the

stitch, 9-31regulating the width of the

zigzag, 9-31removing the work, 9-33setting and timing the needle bar

frame, 9-32setting the hook distance to orfrom needle, 9-32 to 9-33setting the needle, 9-30setting the needle bar, 9-31 to

9-32sewing techniques, 9-33threading the needle, 9-31timing sewing hook, 9-32

Singer sewing machine 211 W 151,9-26 to 9-30

adjustments, 9-27 to 9-30lubrication, 9-30needles, 9-26 to 9-27removing the air shaft connectionbelt, 9-30

Shears, hand tool, 10-9 to 10-10Signal flare, Mk13, Mod 0, 5-2 to 5-3Signaling mirror, 5-1 to 5-2Snaps, harness hardware, 1-12 to 1-13Snaps, three-way locking, 10-14 to 10-15Special inspections, 12-2Spreading gun, installation of, 3-4 to

3-6Square knot, 10-29SRU-31/P, individual aircrewman’s survival

kit, 5-3 to 5-4general packet, 5-4inspection, 5-4medical packet, 5-3

Star punch, hand tools, 10-12Summer flyer’s coverall CWU-27/P and blue

flyer’s coverall CWU-73/P, 4-3 to 4-4Surgeon’s knot, 10-29

Survival radios and beacons, 5-5 to 5-12AN/PRC-63 radio set, 5-5 to 5-7AN/PRC-90 radio set, 5-7 to 5-10AN/PRT-5 transmitting set, 5-11 to

5-12AN/URT-33A beacon set radio, 5-10 to5-11

Survivor’s sling, 5-13 to 5-14

Suspension line continuity check withspreading gun installed, 3-7 to 3-8

SV-2 survival vest, 4-6Swaged ball pull test, 7-4 to 7-7

T

Test stand 1172AS100 oxygen component,11-3 to 11-10

Test stand connections, 11-8Textile materials, terms, and meanings,

10-1 to 10-9construction features and uses of various

textile materials, 10-2 to 10-4difference between threads and cords,

10-4 to 10-5engineering requirements for fabrics,

10-6 to 10-9fiber and filament, 10-1 to 10-2storage of textile materials, 10-5 to

10-6webbings and tapes, 10-4

Three-way locking fasteners, 10-14Three-way locking snaps, 10-14 to 10-15Tools, special hand, 10-9 to 10-12

awl, 10-12foot-operated grommet press, 10-10hand press, 10-10knife, 10-10 to 10-11measuring devices, 10-11 to 10-12sailmaker’s palm, 10-12shears, 10-9 to 10-10star punch, 10-12

Transmitting set, AN/PRT-5, 5-11 to5-12

INDEX-12

Transporting parachutes, 1-13 to 1-14shipping containers, 1-13 to 1-14storing, 1-14

Turnaround/preflight/postflight/transferinspections, 12-7, to 12-8

V

Vacuum pump, 11-9 to 11-10Visual inspection, 7-4

Vol-O-Flo calibration, 11-13Vol-O-Flo element cleaning, 11-13Vol-O-Flo elements, 11-4 to 11-6

W

Water, canned drinking, 5-4 to 5-5Webbings and tapes, 10-4

I N D E X - 1 3

Assignment Questions

Information: The text pages that you are to study areprovided at the beginning of the assignment questions.

Assignment 1

Textbook Assignment: “Personnel Parachute Familiarization.” Pages 1-1through 1-30.

Learning Objective: Identifyprincipal events and personsrelated to the development of theparachute as the principal itemof an aviator’s personal survivalequipment.

1-1.

1-2.

1-3.

1-4.

The first man to be accreditedwith a successful parachute jumpfrom an aircraft was

1. Jodaki Kuparento2. Fausto Veranzio3. Albert Berrv4. Andre Garnerin

Who was the first man to make afree-fall parachute jump from anaircraft?

1. Floyd Smith2. Guy Hall.3 . Major Hoffman4. Leslie Irvin

In what year did it become amandatory requirement for allNavy aircrewmen to wearparachutes?

1. 19182. 19223. 19244. 1923

In what year was the PR rateestablished?

1. 19222. 19243. 19424. 1944

1-5.

1-6.

1-7.

1-8.

1-9.

How many major components make upa standard service parachute?

1. Three2. Four3. Five4. Six

What is the air permeability of1.1-ounce ripstop nylon?

1. 40 to 50 cubic feet persecond

2. 60 to 70 cubic feet perminute

3. 70 to 80 cubic feet persecond

4. 80 to 100 cubic feet perminute

How many sections are in eachgore of a 28-foot canopy?

1. Four2. Three3. Two4. One

The sections used in a parachuteCanopy are cut at a 45-degreeangle to the centerline of thegore. This is known as what typeof construction?

1. Off-center2. Bias3 . Filler4. Warp

Where can thebe found on a

1. Section D2. Section C3. Section A4. Section B

date of manufacture28-foot canopy?

of gore 28of gore 28of gore 28of gore 28

Learning Objective: Identifybasic criteria and associatedfunctions, operating charac-teristics, and methods ofparachute assembly.

1

1-10. What part of a parachute preventsruptures to the canopy duringopening shock?

1. Vent hem2. Skirt hem3. Vent4. Gore

1-11. What size nylon thread should beused for sewing diagonal seams?

1. Either B or E2. F3. FF4. A

1. 100 pounds2. 200 pounds3. 300 pounds4. 400 pounds

1-12. All machine stitching on aparachute canopy (except zigzag)should conform to (a) what typeand (b) what federal standard?

1. (a) 301 (b) 7502. (a) 301 (b) 7513. (a) 302 (b) 7504. (a) 302 (b) 751

1-13. The overall length of asuspension line on a 28-footcanopy iS

1. 14 ft 4 in2. 28 ft 8 in3. 56 ft 10 in4. 75 ft 4 in

1-14. What is the tensile strength oftype III nylon suspension line?

1. 110 pounds2. 220 pounds3. 550 pounds4. 600 pounds

1-15. Which of the following componentsis NOT housed in a parachutecontainer?

1. Harness2. Main canopy3. Suspension lines4. Pilot chute

1-16. Personnel parachute harnesswebbing has a tensile strength of

1. 4,000 to 5,000 pounds2. 6,000 to 7,000 pounds3. 6,000 to 8,000 pounds4. 4,000 to 5,000 pounds

1–17. How many types of parachuteharnesses are used in the Navy?

1. One2. Two3. Three4. Four

1-18. Ripcord pins are swagged in placeand tested at

1–19. Parachute harness fittings areusually made of which of thefollowing metals?

1. Cadmium plated steel2. Chrome plated steel3. Both 1 and 2 above4. Brass plated steel

1-20. What is the tensile strength of aV ring?

1. 1,000 pounds2. 1,500 pounds3. 2,000 pounds4. 2,500 pounds

1-21. How manv types of adapters areused with parachutes?

1. One2. Two3. Three4. Four

1-22. Integrated torso harnessesequipped with SEAWARS aredesigned to automatically releasethe parachute risers uponImmersion in

1. fresh water only2. seawater only3. either fresh water or

seawater

1-23. Several types of snaps used withparachutes include the plain-harness snap, quick-fit snap, andthe quick-connector snap.

1. True2. False

2

1-24. A PR must not only know andobserve the rules for handlingparachutes, but he/she must beprepared to instruct squadronpersonnel in the specific DO’sand DON’Ts of handling them.

1. True2. False

1-25. When placing an RFI parachuteassembly into a shippingcontainer, which of the followingprocedures should you perform?

1. Remove cartridges from allcartridge-actuated devices

2. Chain the parachutesuspension lines

3. Release all snap fasteners4. All of the above

1-26. What is the total amount ofnaphthalene flakes that should besprinkled throughout the para-chute assembly prior to sealingit into a shipping container?

1. 1/4 pound2. 3/8 pound3. 1/2 pound4. 5/8 pound

Learning Objective; Recognizetypes of and criteria forparachute inspections; identifyparachute assemblies to beinspected who inspects them, andhow inspections are performed.Identify forms, symbols,andprocedures used in inspectingparachute assemblies.

1-27. Changes and modifications to aparachute assembly can be issuedby Aircrew Systems Bulletins,Aircrew Systems Changes, orupdated material entered in whichof the following manuals?

1. NAVAIR 13-1-6.12. NAVAIR 13-1-6.23. NAVAIR 13-1-6.34. NAVAIR 11-100-1

1-28. After a parachute assembly isused in an emergency situation,what action is taken?

1. It is shipped to the NavalWeapons Center, China Lake,CA

2. It is shipped to the NavalAir Development Center,Warminster, PA

3. It is shipped to the NavalSafety Center, Norfolk, VA

4. It is disposed of locally

1-29. Periodic maintenance forparachutes fall under thedirection and control of the

1. shop supervisor2. quality assurance officer3. maintenance control officer4. maintenance officer

1-30. All parachute maintenance is doneby the lowest level activityequipped to satisfactorilyperform the work.

1. True2. False

1-31. Mission, time, equipment, trainedpersonnel, and operational needsare not the basic considerationsin determining which levelperforms maintenance on aparachute.

1. True2. False

1-32. Where do you record a 7-day or14-day inspection performed on aparachute?

1. OPNAV Form 4790/382. OPNAV 4790/1013. OPNAV 13484. OPNAV 1030/8

1-33. How many pages make up a Para-chute Configuration Inspectionand History Record?

1. One2. Two3. Three4. Four

3

1–34. Who is responsible for initiating 1-40.the Parachute ConfigurationInspection and History Record?

1. The manufacturer2. The controlling custodians3. The IMA placing the parachute

into service4. The squadron PR

1-35. All required entries on a Para-chute Configuration Inspectionand History Record must belegibly recorded using

1. a ball-point pen2. a typewriter3. either 1 or 2 above4. a felt-tip pen

1-36. Which copy of the parachuteConfiguration Inspection andHistory Record is filed with theaircraft logbook?

1. Hardback copy2. Pink copy3. Flimsy copy4. Yellow copy

1–37. Whenever a canopy is inspectedand found to need repairs, whatform is initiated?

1. A new Parachute Configura-tion Inspection and HistoryRecord

2. A canopy Damage Chart3. A multlcopy MAF4. A NAVAIR-2650

1–38. The daily Inspection Of a para-chute installed in an aircraftcan be performed by which of thefollowing persons?

1. A pilot2. A plane captain3. A line troubleshooter4. Line personnel or issue room

custodians found qualified bythe PR and AME shops

1-39. Only parachutes installed inair-craft are Subject to a special(7-day or 14–day) inspection.

1. True2. False

1-41.

1-42.

1-43.

1-44.

1-45.

a special inspection must includethe harness used for thatspecific parachute inspected.

1. True2. False

If any damage or contamination isfound or suspected while aninspection is being performed,who must the Inspector notify?

1. Line chief2. Duality assurance3. Work center supervisor4. Maintenance control

The original issue inspection ona parachute assembly is performed

1. every 14 days2. at each postcombat inspection3. at the time the assembly is

placed into service4. at each calendar/phased

inspection

A parachute has been used in anemergency situation. Whichinstruction gives you theprocedures to follow to providethe Naval Weapons Center withsufficient information toproperly evaluate the parachute?

1. NAVAIR 4790.22. OPNAV 3750.63. OPNAV 3710.74. NAVAIR 1348

To meet unusual situations orfacilitate workload schedulingshow long can a parachute repackbe delayed?

1. 7 days2. 10 days3. 14 days

Which of the following parts of aparachute assembly are requiredto be sent to the Naval WeaponsCenter (NWC) after use in anemergency?

1. Containers2. Harnesses3. Automatic parachute ripcord

release assemblies4. All of the above

4

1-46. What iS the maximum pull force ona ripcord pull test?

3.1. 22 pounds

25 pounds2. 27 pounds4. 36 pounds

1-47. What tool do you use to adjustthe Clip to meet the pull testrequirements?

1. A screwdriver2. Pliers3. A ball peen hammer4. A setting maul

1 –48. A pilot parachute in a parachuteassembly will become averaged 1month prior to the nextinspection cycle. What actionshould be taken?

1. 9.0 to 11.02. 7.0 to 8.53. 4.0 to 5.04. 0.0 to 3.01. The parachute must be

repacked 1 month early2. The parachute is taken out of

service3. The parachute remains in

service until the next repackcycle

4. The pilot parachute must bereplaced at the repack cycleprior to the expiration date

1. 5 pounds2. 10 pounds3. 15 pounds4. 20 pounds

1-49. What action do you take if acartridge becomes overaged priorto the next scheduled repackinspection?

1-51. When you test for acid and/oralkaline contamination, what isthe safe zone on pH test paper?

1. 0 to 5.02. 5.0 to 9.03. 9.0 to 14.04. 14.0 to 20.0

1–52. What is the full range of pH testpaper?

1. 0.0 to 8.52. 0.0 to 9.03. 0.0 to 10.04. 0.0 to 14.0

1–53. What reading would indicateexcess alkalinity?

1-54. When inspecting suspension linesduring an original issueinspection, how much tension isapplied to the lines?

1-55. When inspecting a parachuteharness, you see a stencil on thehorizontal backstrap that readsR-2–89. What does thisinformation indicate?1. The cartridge is replaced

prior to repack2. The cartridge life may be extended to govern the inspection cycle3. The parachute must be repacked on the date the cartridge expires

1. The harness is to be removed from service in February 19892. The harness was reworked February 19893. The harness is a replacement harness, replaced in February 19894. The harness is a regular size manufactured in February 1989

1-50. If an emergency use canopy failsto show a start of service date,what will be the service life ofthe canopy from the dae ofmanufacture?

1-56. If fewer than trree stitches arebroken or loose on a harnessassembly, what action, if any,should be taken?1. 15 years

2. 12 years3. 10 years4. 7 years

1. Repair it using 6 cord2. Repair it using 3 cord3. Repair it using FF4. None

5

1-57. How many stitches per inch areused to sew a parachute harness?

1. 12 to 142. 10 to 123. 6 to 84. 4 to 6

1-58. What method is used to removesand or dirt from canopy quick-release fittings?

1. High-pressure air (1500-1800psi)

2. Low-pressure air (50 psi)3. Toluene4. Dry cleaning solvent

1-59. On most parachute containers thatuse rubber retaining bands tohold the suspension lines, therubber bands must be replacedevery

1. repack2. other repack3. third repack4. fourth repack

1-60. When are local modificationspermitted on a parachuteassembly?

1. When directed by maintenancecontrol

2. When directed by themaintenance officer

3. When directed by the squadronCO

4. When approved by properauthority

6

Assignment 2

Textbook Assignment: “Automatic Opening Devices,” and “NES-12 Personnel ParachuteSystem.” Pages 2-1 through 2-15 and 3-1 through 3-15.

Learning Objective: Recognizedesign requirements and componentfunctions of the Model 7000automatic parachute ripcordrelease assembly, and identifyprocedures pertinent tomaintaining, inspecting, arming,and disarming it, includingsafety precautions to beobserved.

2-1. Working with an automaticparachute ripcord releaseassembly is the same as workingwith what loaded firearm?

1. .22-caliber pistol2. .38-caliber pistol3. .45-caliber pistol4. Shotgun

2-2. DELETED

2-3. While the firing mechanism isinstalled in a parachute, it islocked by which of the followingparts?

1. The arming pin2. The sear3. The aneroid mechanism4. The locking pin

2-4. Before the preset altitude hasbeen reached, the firingmechanism is prevented fromfiring by which component(s) ofthe release assembly?

1. The actuator stop2. The gear assembly lock3. The firing safety lock4. The aneroid and sear

mechanism

2-5. What action results from theforward movement of the pistonand its attached power cable?

1. The main powder charge in thecartridge explodes

2. The arming cable is pulledbelow the preset altitude

3. The aneroid sear releases thefiring mechanism

4. The locking pins are pulledand the parachute openingsequence begins

2-6. As the piston is forced forwardin the barrel, the power cabletravels what total number ofinches?

1. 2.5 inches2. 2.0 inches3. 3.5 inches4. 3.75 inches

2-7. If any defect is found whileinspecting a ripcord releaseassembly, what action should youtake?

1. Salvage any workable partsfrom the assembly

2. Affix a tag to the assemblydenoting “NOT FOR USE”

3. Remove and scrap the entireassembly

4. Return the assembly to itsmanufacturer

7

2-8. What manual gives you informationon the cartridge servicelife/total life?

1. NAVAIR 11-100-1.12. NAVAIR 11-37103. NAVAIR 11-13-1-6.94. NAVAIR 11-10-100

2-9. Maintenance on any automaticripcord release assembly inservice must be performed at whattimes?

1. Every other time itsparachute assembly isrepacked

2. Only at the original issueinspection

3. Every time its parachuteassembly is repacked

4. Every third time itsparachute assembly isrepacked

2-10. What is the first step inperforming the normal inspectionand maintenance on an automaticripcord release?

1. Remove the aneroid2. Disarm it3. Remove the power cable4. Remove the sear

2-11. All cover and power cablehousings and the receiver andbarrel assemblies have a serialnumber. If you find that aserial number for the coverhousing has the same serialnumber as the receiver assembly,you should report this finding onan Unsatisfactory MaterialCondition Report.

1. True2. False

2-12. When inspecting the leaf springsyou find that the tamper dot onthe retaining screw is missing.You must torque the screw to whatvalue?

1. 10 to 12 inch-pounds2. 12 to 14 inch-pounds3. 14 1/2 to 15 1/2 inch-pounds4. 15 to 16 inch-pounds

2-13. When you inspect the Teflongasket seal, in what positionshould the cup side be facing?

1. The piston2. Away from the piston3. The aneroid seal4. The aneroid detector

2-14. The automatic parachute ripcordrelease test set has a testchamber that can withstand avacuum equivalent to whataltitude?

1. 20,000 feet2. 30,000 feet3. 40,000 feet4. 50,000 feet

2-15. Before using the test set, youmust ensure it has what altimeterbarometric pressure reading?

1. 29.29 inches2. 29.87 inches3. 29.90 Inches4. 29.92 inches

2-16. To test the firing of theautomatic ripcord release, youmust use a dummy cartridge;failure to use this cartridge mayresult in damage to the

1. firing pin2. arming pin3. firewall4. gasket seal

2-17. If you were going to test aripcord release that is set tofire at 14,000±1,000 feet, youwould run the test chamber towhat altitude?

1. 15,000 feet2. 16,000 feet3. 18,000 feet4. 25,000 feet

2-18. By using the descent toggle, thetest chamber will simulate adescent of how many feet persecond?

1. 100 to 1502. 150 to 2003. 175 to 2004. 200 to 250

8

2-19.

2-20.

2-21.

2-22.

2-23.

2-24.

When you test the Model 7000actuator, how many firing checksare made?

1. One2. Two3. Three4. Four

What color lacquer is used forthe tamper dot on the lockingscrew?

1. Red2. Green3. White4. Orange

Learning Objective: Recognizedesign requirements and componentfunctions of the ballisticspreading gun, and identifyprocedures pertinent tomaintaining, inspecting, andchanging the cartridges.

The spreader gun consists of howmany slugs, pistons, andretainers?

1. 72. 143. 214. 28

How is the cartridge installed ina spreader gun?

1. Threaded into the breech2. Loaded into the barrel

assembly3. Loaded into a piston4. Threaded into a piston

What prevents accidental firingof the cartridge during handling?

1. A safety lanyard2. A safety cable3. A safety pin4. A safety lock

What holds the two lines and loopin the channels of each slug?

1. A rubber band2. A safety tie3. A rock washer4. A cover plate

2-25.

2-26.

2-27.

When the cartridge fires, theslugs are propelld outward howmany degrees?

1. 3602. 1803. 904. 45

At a high-speed ejection, thespreading action of the slugsforms what size diameter mouth atthe skirt hem?

1. 10 feet2. 8 feet3. 6 feet4. 4 feet

At a low-speed ejection, thespreading action of the slugsforms what size diameter mouth atthe skirt hem?

1. 10 feet2. 8 feet3. 6 feet4. 4 feet

2-28. After the firing pin iswithdrawn, the firing lanyardexerts how many pounds of tensionon the fail-safe assembly sleeve?

1. 15 to 24 pounds2. 24 to 35 pounds3. 25 to 38 pounds4. 30 to 45 pounds

2-29. If the date the sealed containerwas opened is not available, theinstalled life of the cartridgeis computed from the date ofmanufacture as determined fromthe lot number.

1. True2. False

2-30. The spreader gun cartridge istreated as what class ammunition?

1. A2. B3. C4. D

2-31. The lanyard retaining pin must beremoved when replacing the upperretaining cord.

True2. False1.

9

2-32.

2-33.

2-34.

2-35.

2-36.

2-37.

If you have to remove a damagedor defective spreading gun, whichof the following steps apply?

1. Slip all the suspension linesand attached loops from underthe plates

2. Disconnect the retaining cordfrom the vent lines

3. Both 1 and 2 above4. Cut the retaining cord at the

apex

When performing a firing pinrelease test, the pull force mustbe in what range?

1. 15 to 20 pounds2. 25 to 38 pounds3. 30 to 48 pounds4. 35 to 50 pounds

What is used to clean thecartridge chamber and threads ofa spreading gun?

1. Denatured alcohol2. Dry-cleaning solvent3. WD-404. Warm, soapy water

What is used to mark informationon a spreading gun cartridge?

1. Red marking fluid2. Green marking ink3. White marking fluid4. Black marking ink

When a cartridge is properlyinstalled into the chamber, thebase of the cartridge should bein what approximate position inrelation to the edge of thechamber?

1. Two threads above the topedge

2. Even with the top edge3. TwO threads below the bottom

edge4. Even with the bottom edge

What is the torque value of thecartridge when it is placed intothe

1.2.3.4.

chamber?

97±12 inch-pounds70±10 inch-pounds54±8 inch-pounds84±12 inch-pounds

2-38.

2-39.

2-40.

2-41.

2-42.

Learning Objective: Recognizecomponent functions and operatingcharacteristics of the NES-12personnel parachute system.

When an aircrew member ejectsfrom an aircraft, what causes theexternal pilot parachute to open?

1. The spreading gun2. The automatic ripcord release3. A static line4. The external pilot chute

release assembly

At speeds up to 90 knots, thetristage pilot chute does which,if any, of the following?

1. Inflates fully2. Reduces to 18 inches3. Reduces to 24 inches4. None of the above

At speeds between 90 and 250knots, the tristage pilot chutedoes which of the following?

1. It reduces in size to 18inches

2. It reduces in size to 24inches

3. It reduces in size to 30inches

4. It inverts

The suspension lines are pulledfrom the container by which ofthe following parachutecomponents?

1. External pilot chute2. Spreading gun3. Internal pilot chute4. Main canopy

If the spreading gun fails tofire, what permits the canopy toopen?

1. The slugs separate from thegun at full suspension linestretch

2. The slugs have breakawaycover plates

3. The override disconnectreleases the slugs

10

2-43. The NES-12 prsonnel parachutesystem utilizes what type ofcanopy?

1. 26-foot2. 26-foot modified3. 20-foot modified4. 32-foot

2-44. The shoulder restraint system forthe NES-12 is located on which ofthe following parachuteassemblies?

1. Riser assembly2. Container assembly3. Harness assembly

Learning Objective: Identifyprocedures for inspecting,rigging, and packing the NES-12parachute assembly.

2-45. When a step iS followed by “(QA)”in the rigging and packingprocedure, all work stops untila quality assurance inspectorperforms the requirements listedat the end of the applicableprocedures.

1. True2. False

2-46. How do you obtain a completeNES-12 parachute assembly toplace into service?

1. Order the complete assembly2. Order each part separately3. Order a container and use

spare parts to assemble acomplete NES-12

2-47. If you are in the process ofrepacking a parachute and it istime to secure, what action mustyou take to complete therepacking procedures?

1. Complete the repack beforeyou secure

2. Secure and restart theprocedure the next day fromstep one

3. Either 1 or 2 above,depending upon thecircumstances

4. Lay a covering over theassembly and start at thatstep the next day

2-48. To attach the internal pilotparachute to the NES-12 assembly,you must use what type ofknot(s)?

1. Bowline2. Square3. Clove hitch and a half hitch4. Larks head

2-49. When positioning the spreadinggun for installation onto aparachute canopy, it is placedbetween which of the followingsuspension lines?

1. 1 through 14 and 15 through28

2. 1 through 28 and 14 through15

3. 21 through 7 and 28 through 84. 7 through 14 and 28 through

21

2-50. To route the retaining cordthrough the main canopy, what, ifanything, is used?

1. Type I suspension line2. Type II suspension line3. Type III suspension line4. Nothing

2-51. When positioning the spreadinggun at the skirt hem, the gunshould be rotated so that whichlabeled slug is facing up?

1. 28-12. 14-133. 12-134. 1-28

2-52. What torque value is used tosecure the slug plates to thespreading gun?

1. 5±1/2 pound-inches2. 7±1/4 pound-inches3. 10±1 pound-inches4. 6±1/2 pound-inches

2-53. What tool is used to push thesear into the barrel of theoverride disconnect?

1. A temporary locking pin2. A bodkin3. A straight slot screwdriver4. A jewelers wrench

11

2-54.

2-55.

2-56.

2-57.

2-58.

The tacking that holds theoverride disconnect to the pilotparachute connector strap istacked how far above the knotsecuring the connector strap tothe vent lines?

1. 5±1/2 inches2. 4±1/2 inches3. 3±1/4 inches4. 2±1 inches

What type of thread/cord is usedto tack the override disconnectto the pilot chute connectorcord?

1. E thread2. FF thread3. 3-cord4. 6-cord

To stow the firing lanyard intothe stowage sleeve, you must usewhat tool(s)?

1. A packing hook2. Type I nylon line and a

bodkin3. Rubber bands4. Type III nylon line and a

screwdriver

What size of thread is used totack the second lanyard bight tothe stowage sleeve?

1. A nylon thread2. E nylon thread3. F nylon thread4. FF nylon thread

Which of the following manualswould you use to ensure you areinstalling the proper armingcable and time-delay cartridge?

1. NAVAIR 13-1-6.52. NAVAIR 13-1-6.43. NAVAIR 13-1-6.34. NAVAIR 13-1-6.2

2-59.

2-60

2-61.

2-62

2-63.

The breakcords used to secure thelift web protector flaps over therisers are constructed from

1. three-strand cord2. four-strand cord3. FF thread4. E thread

What type of knots are used tosecure the breakcords?

1. Lark’s head2. Surgeon’s knot and a square

knot3. Two half-hitches4. Two half-hitches and a

clove-hitch

The connector link ties areconstructed from (a) how manylengths and (b) what type cord?

1. (a) Two 12-inch(b) 100-pound nylon cord

2. (a) Two 14-inch(b) Type I cotton cord

3. (a) Two 24-inch(b) 150-pound nylon cord

4. (a) TWO 16-inch(b) Type III cotton cord

The loop used in the connectorlink ties is tied with what typeknot(s)?

1. Overhand knot2. Lark’s head knot3. Bowline and overhand knot4. Lark’s head and overhand knot

When you install the releaselanyard and ripcord assemblies,YOU must ensure that thebaseplate clamp is in whatposition?

1. To the right of the hex nutlocking pin

2. Over the locking pin prior toinstalling the hex nut

3. To the left of the hex nutlocking pin

4. Over the hex nut prior toinstalling the locking pin

12

2-64. When routing the firing lanyardthrough the lanyard guidegrommet, where is the 36-inchmark on the lanyard placed?

1. Under the bar on theconnector link

2. Over the bar on the connectorlink

3. Under the cross-connectorstrap

4. Over the cross-connectorstrap

2-65. When routing the firing lanyardthrough the suspension lines, itis routed between what lines?

1. 1 and 282. 14 and 153. 7 and 84. 16 and 15

13

Assignment 3

Textbook Assignment: “Aircrew Personal Protective Equipment,” Pages 4-1 through4-32.

3-1.

3-2.

3-3.

3-4.

3-5.

Learning Objective: Maintain,repair, and make authorizedmodification to flight clothing?

What is/are the primaryfunction(s) of flight clothing?

1. Protection2. Comfort3. Appearance4. All of the above

What factor decides thedifference between protection andcomfort?

1. Aircraft design2. Operational condition3. Size of the aircrew member4. Type of material

Material that is used in themanufacture of flight clothing iSdesigned to

1. lengthen service life2. provide comfort3. improve survival chances4. provide a nice appearance

Planned maintenance for flightclothing is performed at whatlevel of maintenance

1. O level2. I level3. Depot level4. The level set forth in the

OPNAVINST 4790.2

Flight clothing maintenance isdivided into how many categories?

1. One2. Two3. Three

3-6.

3-7.

3-8.

3-9.

3-10.

When you clean a helmet. whattype of maintenance is beingperformed?

1. Calendar2. Corrective3. Phase4. Preventive

Who schedules preventivemaintenance for all aircrewPersonal protective equipmentwithin a squadron?

1. Maintenance/material controlofficer

2. Production control officer3. Shop chief4. Quality assurance

What is used to make entries on amaintenance document?

1. A blue pen2. A black pen3. A typewriter4. Any of the above

When signing a maintenancedocument you are required toperform which of the followingactions?

1. Print your name2. Use your initials only3. Sign your full name4. Any of the above

What document is used to enterthe equipment assigned to anaircrew member?

1. DD 13482. Aircrew Personal Protective

History Card3. NAVAIR 13484. Form 4790/2E

4. Four

14

3–11. The Aircrew Personal ProtectiveEquipment History Card is dividedinto how many sections?

1. One2. Two3. Three4. Four 1. 300° to 400°F

2. 500° to 600°F3. 700° to 800°F4. 800° to 900°F

3-12. When you are working withpersonal protective equipment,which of the following NAVAIRmanuals is most helpful?

1. 13-1-6.72. 1-1–6.53. 17–1–6.44 . 13-1-6.2

3-13. Who is the only authority thatcan authorize modification tosurvival equipment?

1. NMPC2. OPNAV3. COMFAIR4. NAVAIRSYSCOM

3–14. What field activity hascognizance over most life supportand survival equipment?

1. NWC, China Lake, Ca2. NAVAIRDEVCEN, Warminster, PA3. NAEC, Lakehurst, NJ4. NAEC, San Diego, CA

3-15. The field activity withcognizance over all survivalradios and URT-33 emergencybeacons is

1. NADEP, Pensacola2. NADEP, Jacksonville3. NAEC, Lakehurst4. NASC, Pensacola

3-16. If you are requested to sew agroup of patches on a flightjacket, you would be allowed tosew up to how many square inchesof patches?

1. 150 square inches2 100 square inches3. 50 square inches4. There is no limit

3-17. The CWU–27/P and CWU-73/P summerflying coveralls are made from anAramid cloth. This material willnot support combustion, but willbegin to char at whattemperature?

3-18. The CWU-27/P and CWU-73/Pcoveralls can be washed and driedin up to which of the followingtemperatures before damage orshrinkage occurs?

1. 100°F water and 120°F dryingtemperature

2. 120°F water and 160°F dryingtemperature

3. 110°F water and 140°F dryingtemperature

4. 140°F water and 180°F dryingtemperature

3-19. The GS/FRP-2 flyer’s gloves areavailable in how many sizes?

1. 62. 73. 84. 9

3-20. After laundering a pair ofGS/FRP-2 flyer’s gloves, theproper way to remove excess wateris to

1. squeeze them out2. wring them out3. place the gloves in a dryer4. drip dry them

3-21. Flyer’s boots come in which ofthe following size ranges?

1. 6 regular through 16 wide2. 5 1/2 narrow through 15 1/2

narrow3. 4 narrow through 14 1/2 extra

wide4. 5 1/2 wide through 13 regular

15

3-22.

3-23.

3-24.

3-25.

3-26.

The SV-2B survival vest providesmaximum storage for survivalequipment. In addition, itprovides for integration of whichof the following items?

1. A life preserver2. Anti-g coveralls3. A chest-mounted oxygen

regulator4. All of the above

3-27.

3-28.

Learning Objective: Identifyrequirements for wearing anti-exposure suits.

Antiexposure suits must be wornin what maximum watertemperature?

1. 32°F or below2. 40°F or below3. 50°F or below4. 65°F or below

What maximum air temperaturerequires that antiexposure suitsbe worn?

1 . 32°F or below2. 40°F or below3. 45°F or below4. 50°F or below

The antiexposure assembliesshould be sized to aircrewmembers by using their

1. suit size2. height, weight, and chest

measurements3. chest and height measurements4. torso measurement.

The CWU-23/P liner is supplied inhow many sizes?

1. 82. 103. 124. 14

The CWU–62/P antiexposurecoverall is supplied in how manysizes?

1. 92. 103. 114. 12

If neck seal trimming isnecessary, trimming incrementsshould not be more than

1. one-eighth inch at a time2. one-quarter inch at a time3. one–half inch at a time4. one inch at a time

3-29.

3-30.

3-31.Learning Objective: Identifythe characteristics of theA/P22P-6(V)2 and A/P22P-6A(V)2antiexposure assemblies.

SRU–25/P rubber socksselected based on the aircrewmembers boot size

1. True2. False

When attachingThe A/P22P series antiexposureassemblies are designed to be a

3-32. the rubber socks

1. quick-donning type2. continuous wear type3. both 1 and 2 above

to the antiexposure assembly, howmany stitches per inch are used?

1. 2 to 62. 3 to 53. 5 to 74. 8 to 10What is the only difference

between the A/P22P-6(V)2 and theA/P22P-6A(V)2 antiexposureassemblies? Learning Objective: Maintain,

repair, and place anti-g garmentsinto service.1. The type of coveralls

2. The type of material3. The type of gloves4. The type of liner

16

3-33. How many G’s can an averageaircrew member withstand withoutthe aid of an anti-g garment?

1. 4.5 to 5.52. 6.0 to 7.03. 6.5 to 7.54. 10.0 to 12.0

1. 2 psi2. 3 psi3. 4 psi4. 5 psi

3-34. DELETED

1. 1.0 psig2. 2.0 psig3. 3.0 psig4. 4.0 psig

3-35. Which of the following g forceswould have the most harmfuleffect on your body?

1. 2 g’s for 1 minute2. 3 g’s far 1 minute3. 6 g’s for 3 minutes4. 12 g’s for 1 second

3-36. The CSU-15/P anti-g garment isavailable in how many sizes?

1. 42. 63. 84. 10

3-37. A preflight inspection on ananti-g garment is performed bythe aircrew member before eachflight. The interval betweenpreflight inspections must notexceed how many days?

1. 22. 73. 104. 14

3-38. A calendar inspection on theCSU-15/p anti–g garment isperformed every

3-39. When perfoming the leakage teston a CSU-15/P anti-g garment, thebladder is inflated to

3-40. The anti-g suit bladder beingtested should not lose more thanhow many psi in 30 seconds?

3-41. Anti-g coveralls should becleaned by

1. machine washing2. dry cleaning3. hand-washing in cold water4. hand-washing in hot water

3-42. The proper procedure for dryingthe anti-g garment is to

1. dry them in direct sunlight2. hang them on a wooden hanger

in a dry, ventilated area3. tumble dry on gentle cycle4. wring them dry by hang

Learning Objective: Inspect,maintain, and fit integratedtorso harnesses.

3-43. The MA-2 torso harness integratesthe aircrew member’s

1. lap belt and seat pan only2. parachute harness and lap

belt only3. parachute harness, lap belt,

and shoulder harness4. lap belt and shoulder harness

only

1. 180 days2. 91 days3. 60 days4. 30 days

3-44. The MA-2 torso harness isavailable in how many sizes?

1. 102. 123. 144. 16

17

3-45. Where is the gated D-ringattached to the MA-2 torsoharness?

1. Left and right shoulders2. Right shoulder3. Left shoulder4. Cross-connector strap

3–46. Which of the following activitieswould you consult to determine ifa custom made torso harness isnecessary?

1 AIMD2. NETPMSA3. NAVAIRDEVCEN4. Physiology unit

3-47. When fitting the MA-2 torsoharness, the ideal location forthe male kock fittings should be

1. in the hollow below thecollar bone when the aircrewmember is standing

2. in the hollow below thecollar bone when the aircrewmember is sitting

3. in the hollow below theCOllar bone when the aircrewmember is sitting or standing

4. two inches below the collarbone

3-48. How many types of inspections areperformed on the MA-2 torsoharness?

1. One2. Two3. Three4. Four

1. 102. 123. 154. 173-49. The calendar inspection must be

done how often?3-54.

1. Once a month2. Every 210 days3. Every 61 days4. Each time the aircrew

member s personal protectiveequipment is inspected

3-50. What is the service life of theMA-2 torso harness?

1. 12 years from the date placedin service

2. 10 years from the date placedin service

3. 15 years from the date placedin service

4. 12 years from the date Ofmanufacture

3-51. Where can you find the placed inService date on a torso harness?

1. On the left leg strap2. On the right leg strap3. In the center of the lap belt

strap4. In the center of the back

strap

3-52. Which manual would you use tofind detailed information on theMa-2 torso harness?

1. NAVAIR 13-1-6.32. NAVAIR 13-1-6.23. NAVAIR 13–1-6.54. NAVAIR 13-1-6.7

Learning Objective: Inspect,maintain, and fit protectivehelmets for aircrew members.

3—53. How many different configurationscan be made from the basicPRK-37/p helmet shell?

Which of the following helmets isused in the S-3A aircraft?

1. HGU-43/P2. HGU-49/P3. HGU-46/P4. HGU-47(V)3/P

3-55. What is the designation of thesingle lens visor assembly?

1. AVG-82. PRU-36/P3. EEK–3/P4. EEK-4A/P

18

3-56.

3-57.

The PRK-37/P helmet shells areavailable in how many sizes?

1. Three2. Four3. Five4. Six

Which of the following isrecommended to clean the shelland edge roll of a helmet?

1. Ammonia and water2. Brillo pad3. Mild detergent and water4. Canopy polish

What percentage of a helmet mustbe covered with reflective tape?

1. 75 percent80 percent

3. 90 percent4. 100 percent

What colors are recommended for

3-58.

2.

3-59.

2.

use when taping a helmet?

1. Green and redWhite and red

3. Blue and white4. White and orange

The SPH–3C helmet is Supplhow many sizes?

1. Two2. Three3. Four4. Six

3-60. ied in

3-61. Liners for the SPH-3C helmet are

3-62.

provided in which of thefollowing sizes?

1. 1/4 and 3/4 inch2. 1/2, 3/8, and 15/16 inch3. 1/4, 1/2, and 5/8 inch4. 1/2 and 3/4 inch

What percentage of visible lightis transmitted in the neutralvisor of a SPH-3C helmetassembly?

1. 3 to 5 percent2. 8 to 16 percent

20 to 30 percent3.4. 85 percent or greater

3-63.

3-64.

3-65.

3-66.

3-67.

3-68.

How often are protective helmetssubjected to a calendarinspection?

1. Every 210 days2. Every 180 days3. Every 120 days4. Every 90 days

Learning Objective: Inspect,maintain, and fit the pressure-demand oxygen mask.

The MBU-12/P oxygen mask willcontinue to function at a depthof

1. 10 feet underwater2. 12 feet underwater3. 16 feet underwater4. 20 feet underwater

How many different configurationscan be made from the MBU-12/Poxygen mask?

1. S i x2. Five3. Four4. Two

Which of the following manualswill give complete information ona MBU-12/P oxygen mask configura-tion buildup?

1. NAVAIR 13-1-6.42. NAVAIR 13-1–6.73. NAVAIR 00-80T-1014. NAVAIR 13-1-6.1

When fitting the mask to anaviator, how far are the bayonetfittings inserted into thereceiver assembly?

1. Until it is snug2. To the first locking position3. To the third locking position4. To the second locking

position

After adjusting the straps on thebayonet fittings you should tackthem in place with

1. two turns of E thread2. one turn of E thread3. two turns of A thread4. one turn of FF thread

19

3-69. How often is a calendar inspec-tion conducted on an oxygen mask?

1. 180 days2. 90 days3. 30 days4. 60 days

3-70. The preferred solution forcleaning the oxygen mask is amixture of 1/4 to 1/2 ounce ofcleaning compound added to

3-71. To clean the inhalation/exhalation valve, you should use

1. Clorox and distilled water2. benzalkonium chloride and

distilled water3. isopropyl alcohol and

distilled water4. either 2 or 3 above

1. 1 pint of water2. 1 gallon of water3. 2 gallons of water4. 1 quart of water

20

Assignment 4

Textbook Assignment: “Rescue and Survival Equipment.” Pages 5-1 through 5-22.

Learning Objective: Inspect,maintain, and advise aircrewmembers on the use of rescueequipment and survival items.

How far can the dye marker beseen from an altitude of 3,000feet?

1. 3 miles2. 5 miles3. 8 miles4. 10 miles4-1. Survival items may be carried

which of the following places?

1. Life rafts2. Droppable kits3. On the aircrewman4. All of the above

The signaling mirror can producea light the equivalent of howmany candlepower?

1. 6,000,0002. 8,000,0003. 10,000,0004. 11,000,000

4-2. Which of the following manualscovers survival items?

1. NAVAIR 13-1-6.72. NAVAIR 13-1-6.53. NAVAIR 13-1-6.24. NAVAIR 13-1-6.1

4-6.

4-7.

4-8.

4-9.

4-10.

4-11.

On a bright sunny day, theflashes from a signal mirror canbe seen form a distance of

4-3. DELETED1. 10 miles2. 20 miles3. 40 miles4. 50 miles

The Mk 79 Mod 0 signal kit issupplied with what total numvberof Mk 80 Cartridges?

1. 72. 83. 104. 124-4. How long does it take to exhaust

a sea dye marker?

When fired, each cartridge flarehas a minimum duration of1. 1 hour

2. 10 to 15 minutes3. 20 to 30 minutes4. 40 to 50 minutes

1. 4 seconds2. 4 1/2 seconds3. 5 seconds4. 5 1/2 seconds4-5. The dye marker ceases to be a

good target after being dispersedfor approximately what period oftime?

How many feet will the Md 80,signal flare travel when it islaunched?

1. 1 hour2. 2 hours3. 45 minutes4. 30 minutes

1. 1002. 1503. 2004. 250

21

4-12. The Mk 13, Mod 0 signal flare 4-18.will burn for approximately whatmaximum period of time?

1. 10 seconds2. 20 seconds3. 30 seconds4. 40 seconds

4-13. The lot number of the flare 4-19.should be checked each time theflare is inspected. The lotnumbers of flares that are notserviceable can be found in whichof the following publications?

1. NAVAIR 13–1–6.52. Cut-rent aircrew equipment

bulletins3. NAVAIR 11-15-74. Current revisions to the

NAVAIR 13-1–6.7

4-14. Which of the following distresssignals is commonly called astrobe light?

1. SL–5/E2. LT-653. SLT-73/E4. SDU–5/E

4-15. You are required to inspect theSDU-5/E distress light a minimumof how often?

1. Every 30 days2. Every 60 days3. Every 90 days4. Every 120 days

4-16. The SDU-5/E distress light isrequired to flash how many timesper minute for a 2–minuteduration?

1. 50 ± 102. 40 ± 53. 30 ± 104. 20 ± 5

4–17. The SRU-31/P survival kitconsists of two parts. Whatperson/activity is responsiblefor the medical items in packetnumber one?

1. The squadron supply officer2. The local medical department.3. The squadron PR4. The aircrew member

4-20.

4–21.

4–22.

4–23.

The eye ointment that is carriedin the SRU-31/P survival kit hasan expiration date Of

1. 7 years2 years2.

3. 3 years4. 5 years

What is the purpose Of therations that are carried byaircrew personnel?

1. To provide subsistence2. To alleviate thirst3. To provide nourishment4. To provide quick energy, only

An emergency drinking water cancontains what total amount ofwater?

1. 6 ounces2. 8 ounces3. 10 ounces4. 12 ounces

The shelf life and the servicelife of canned water isindefinite, as long as the canspass what test?

1. Slap test2. Leakage test3. Pressure test

Learning Objective: Test andmaintain survival radios.

The AN/PRC-63 radio set has howmany modes of operations?

1. One2. Two3. Three4. Four

Which of the following modes ofoperation is NOT used in theoperation of the AN/PRC–63?

1. Beacon2. Voice transmission3. Voice reception4. Automatic SOS

22

4-24.

4-25.

4-26.

4-27.

4-28.

4-29.

What feature of the AN/PRC-63radio will let the aircrewmember know that his radio isputting out a signal?

1. A beacon cotnfidence tone2. A toggle switch3. A micro-transceiver4. A red light

The AN/PRC-63 radio has a voicecommunication range of up toapproximately what distance?

1. 10 miles2. 25 miles3. 50 miles4. 75 miles

A search aircraft flying at10,000 feet can locate atransmitting beacon up toapproximately what distance?

1. 25 miles2. 50 miles3. 70 miles4. 80 miles

The lanyard attached to thedeployment device on theAN/PRC-63 radio must be able towithstand a pull of what minimumamount?

1. 20 pounds2. 25 pounds3. 50 pounds4. 110 pounds

When transmitting on theAN/PRC-63 radio, where shouldthe

1.

radio be held?

Next to the mouth and at a43° angleTwo inches from the mouth ata 45° angleNext to the mouth and uprightOne to two inches from the

2.

3.4.

mouth and upright

To increase the receiving soundon your AN/PRC-63, what shouldyou do?

1. Turn the volume controlclockwise

2. Turn the volumecounterclockwise

3. Turn the beacon selector to“loud”

4. Turn the beacon selector to“loudest”

4-30.

4-31.

4-32.

4-33.

4-34.

4-35.

Which of the following units isused to test the operation of theAN/PRC-63?

1. AN/PRC-63T2. AN/PRC-36T3. AN/PRC-904. AN/PRM-32

Which of the following pubica-tions would you use to findinformation on the testingprocedures for the AN/PRC-90radio?

1. NAVAIR 13-1-6.52. NAVAIR 13-1-6.73. NAVAIR 16-30PRC90-24. NAVAIR 16-30PRC63-1

What is the shelf/service life ofthe Mallory battery used in theAN/PRC-63 radio?

1. 36 months from the date ofmanufacture

2. 24 months from the date ofmanufacture

3. 36 months from the dateplaced in service

4. 24 months from the dateplaced in service

Under ideal conditions, theAN/PRC-90 radio has a maximumvoice range of how many nauticalmiles?

1. 1002. 753. 604. 50

The tone (code signal) on theAN/PRC-90 radio has a maximumrange of how many nautical miles?

1. 502. 803. 904. 100

The shelf life of a battery isbased on storage temperature.What is this temperature?

1. 40°F2. 50°F3. 60°F4. 70°F

23

4-41.Learning Objective: Identifyspecifications and performancecapabilities of survival radios.

For information on search andrescue procedures at sea youwould refer to what publication?

1. OPNAV 4790.22. NAVAIR 80T-1013. NWP 19-14. OPNAV 3710.7

4-36. To place the AN/PRC-90 radio ona guard channel beacon operation,you would set the function to

4-42.1. MCW-137.02. BCN-243.03. ABC-252.04. CBA-243.0

A survivor should never touch arescue device until it hastouched the ground or water forwhat reason?

4-37. Which of the folowing radios isstrictly a beacon radio set?

1. The divice must be stopped first2. The device has to be grounded to prevent electrical shock3. This will ensure the device will not release unexpectly4. The survivor must be sure the helicopter is on the proper wind line

1. AN/PRC-32A2. AN/PRC-633. AN/URT-33A4. AN/URT-63

4-38. What is the storage life of abattery used in the AN/URT-33A? 4-43. The survivor's sling is

constructed with what typefilling?

1. 12 months at 60°F2. 18 months at 90°F3. 24 months at 70°F4. 36 months at 70°F

1. Kapok2. Styrofoam3. Foam rubber4. Polyurethane4-39. When the AN/PRT-5 is activated,

it will send out signals on whichof the following frequencies? 4-44. The survivor's sling is

identified by what color(s)?1. 83.64 MHz2. 843.6 and 234.0 MHz3. 2.430 MHz4. 8.364 and 243.0 MHz

1. Red2. Orange and white3. Yellow4. Red and white

4-40. At 77°F the battery pack for theAN/PRT-5 is designed to givecontinuous operation for

4-45. The rescue sling is designed tocarry how many people at onetime?

1. 48 hours2. 60 hours3. 72 hours4. 96 hours

1. One2. Two3. Three

4-46.Learning Objective: Identify theconstruction and characteristicsof helicopter rescue equipmentsuch as the survivors sling andthe rescue seat.

The calendar inspection on therescue sling is performed atinterviews not to exceed how many days?

1. 60 days2. 90 days3. 120 days4. 225 days

24

4–47. When testing the survivor’s slingon a webbing tester what load isapplied to the sling?

1. 300 pounds2. 500 pounds3. 600 pounds4. 1,000 pounds

4–48. The rescue seat has (a) whattotal number of prongs and (b)the prongs are how many degreesapart?

1. (a) 2 (b) 1800

2. (a) 3 (b) 120°3. (a) 4 (b) 90°

4–49. If the rescue seat has beenimmersed in salt watery it mustbe cleaned with

1. solvent2. gasoline3. mild soap and water4. a special chemical mixture

Learning Objective: Identify theoperational characteristics ofthe forest penetrator and rescuenet.

4–50. The forest penetrator iS acompact rescue device that haswhat approximate weight?

1. 10 pounds2. 20 pounds3. 30 pounds4. 37 pounds

1. 10 1/2 pounds2. 12 pounds3. 21 1/2 pounds4. 25 pounds

4–51. How long are the safety strapsthe forest penetrator?

1 . 4 feet 9 1/4 inches2. 5 feet 9 inches3. 6 feet4. 8 feet

4–52. With the flotation collarinstalled, how far above thesurface of the water will theforest penetrator float?

4-53. The forest penetrator is designedto accommodate up to how manysurvivors at a time?

1. One2. Two3. Three4. Four

4-54. All forest penetrators aresubjected to a calendarinspection every

1. 60 days2. 90 days3. 181 days4. 223 days

4–55. When you perform a calendarinspection on the forestpenetrator, you must compare themarkings on it and the markingson the flotation collar. Whatmanual would you use to ensurethey are the applicable markings?

1. NAVAIR 13-1-6.52. NAVAIR 13-1-6.72. NAVAIR 00-8OT-1014. NAVAIR NWP-19–1

4-56. How many pounds does the rescuenet weigh?

4-57. How long is the sea anchorretaining line on the rescue net?

1. 10 feet2. 12 feet3. 15 feet4. 20 feet

4-58. During moderate seas the seaanchor should be attached to therescue net so that it will extendhow far?

1. 20 feet.2. 15 feet3. 10 feet4. 5 feet

1. 5 inches2. 2 inches3. 6 inches4. 4 inches

Learning Objective: Conductperiod inspections and test ofrescue harnesses, rescue hooks,and cattle cutters.

25

4-59. A calendar inspection is per-formed on the rescue harness aminimum of how often?

4-66. The hoist quick-splice plate is used under which of the followingconditions?

1. Every 60 days2. Every 90 days3. Every 210 days4. Every 225 days

1. When the hoist cable is cut or broken2. When time is a factor3. When no other means is available for rescue4. All of the above4-60. The service life of the rescue

harness is 7 years from the dateit was placed into service, butit is NOT to extend beyond whatlength of time from the date offabrication?

4-67. The cable grip is an emergencycondition device that is capableof supporting what maximumweight?

1. 8 1/2 years2. 9 years3. 10 years4. 12 years

1. 1,000 pounds2. 1,500 pounds3. 2,000 pounds4. 2,500 pounds

4-61. If a service date cannot be determined, the rescue harnessmust be removed from service whatmaximum number of years from thedate of manufacture?

4-68. The pneumatic rescue hand tooloperates on a nitrogen gascylinder with a pressure of

1. 1,000 psi2. 2,000 psi3. 3,000 psi4. 3,500 psi

1. 52. 73. 8 1/24. 10 4-69. The hand tool can cut stainless

steel cable of what maximumdiameter?4-62. When you clean the rescue

harness, the water must not exceed what temperature? 1. 1/8 inch

2. 1/4 inch3. 5/8 inch4. 7/32 inch

1. 90°F2. 100°F3. 120°F4. 150°F 4-70. To pass the trigger force test,

the hand tool trigger force must be in what range?4-63. The large rescue hook will

support how much weight?

1. 1,500 pounds2. 2,000 pounds3. 2,500 pounds4. 3,000 pounds

1. 2 and 5 pounds2. 5 and 20 pounds3. 20 and 25 pounds4. 25 and 27 pounds

4-71.4-64. The smaller rescue hook supports

what maximum weight?

After clenaing the hand tool, youshould lightly coat the cuttingedge of the blade with what?

1. 500 pounds2. 1,000 pounds3. 2,500 pounds4. 2,000 pounds

1. Light weight oil2. Bearing grease3. Pneumatic grease4. Heavy weight oil

4-65. The ring will support whatmaximum weight?

1. 500 pounds2. 1,000 pounds3. 1,500 pounds4. 2,000 pounds

26

Assignment 5

Textbook Assignment: “Inflatable Survival Equipment.” Pages 6-1 through 6-35.

5-5.Learning Objective: Recognizelife raft construction materialsdesign features, stowagelocations, and configurations;identify inflation procedures;and describe repair requirementsfor life rafts.

5-1.

5-6.

5-2.

All inflatable survival equipmentis subjected to periodic mainte-nance under the direction of the

1. maintenance/material controlofficer

2. maintenance chief3. work center supervisor4. quality assurance officer

To meet unusual situations, thecalendar inspections on inflat-able equipment may be extended upto what maximum number of days?

1. 5 days2. 7 days3. 10 days4. 14 days

For aircraft that are in phase

5-7.

5-3.maintenance, the time extendedfor periodic maintenance can beextended to plus or minus whatpercent of the time cycle’?

1. 52. 103. 154. 20

5-4. Life rafts installed in thefuselage require a dailyinspection. This inspection canbe performed by which of thefollowing persons?

1. The plane captain (designatedand instructed}

2. The aircrew member(designated and instructed)

3. The PR4. All of the above

DELETED

How oftenperformed

1. Every2. Every3. Every4. Every

is a functional teston a life raft?

inspectionother inspectionthird inspectionfourth inspection

When you are performing afunctional test, the life raftshould inflate to its designedshape in less than what maximumamount of time?

1. 1 minute2. 2 minutes3. 3 minutes4. 30 seconds

When applying a5-8.load test,force must

1. 252. 303. 504. 75

pull cable proofhow many pounds ofbe applied?

5-9. Which of the folcan be inflatedinflation tube?

1. LR-12. LRU-12/A3. LRU-13/A4. LRU-15/A

lowing life raftsby using an oral

27

5-10. Before you test the pressure in aflotation compartment during aleakage test, you must wait aminimum of how many hours afterthe final pressure adjustment iSmade?

1. 822.

3. 244. 4

5-11. To clean a life raft you woulduse a cleaning compound mixedwith water. This mixture shouldconsist of one part of compoundto how many parts of water?

1. Six2. Five3. Three4. Four

5-12. CO2 cylinders for multiplace liferafts are subjected to a hydro-static test a minimum of howoften?

1. Yearly2. Every 2 years3. Every 3 years4. Every 5 years

5-13. When installing an inflationvalve onto a CO2 cylinder thatwill be used on a multiplace liferaft, you would torque it to howmany inch-pounds?

1. 400±402. 600±603. 800±804. 900±90

5–14. What is the hydrostatic testinterval, if any, for an LR–1life raft cylinder?

1. None2 . 2 years3 . 5 years4. 4 years

5—15. CNO has established that liferafts Will carry enough equipmentfor an aircrew member to becapable of surviving for howlong?

5-16. When repairing a loose or missingseam tape, you must overlap theseam tape on other seams at leasthow many inches?

1. 12. 23. 34. 4

5-17. What is recommended to remove orloosen damaged tape on a liferaft?

1. Cleaning compound2. Toluene3. Gasoline4. M.E.K.

5—18. How many coats of toluene areapplied to an area that you aregoing to repair?

1. One2. Two3. Three4. Four

5-19. How many coats of cement areapplied to the raft when you makea repair?

1. One2. Two3. Three4. Four

5-20. When applying cement to a patch,how long should you wait betweenthe first and the last coat?

1. 10 minutes2. 15 minutes3. 20 minutes4. 25 minutes

5-21. How long must you wait beforeapplying talcum powder to thepatch area?

1. 12 hours2. 24 hours3. 36 hours4. 48 hours

5-22. You must scallop the edge of apatch that is larger than whatmaximum size?

1. 12 hours2. 24 hours3. 72 hours4. 96 hours

1. 6 inches2 inches2.

3. 3 inches4. 5 inches

28

5-23. 5-29.

5-24.

5-30.

5-25.

Righting handles are provided onall life rafts EXCEPT which ofthe following?

1. LRU-12/A2. LRU-13/A3. LRU-14 series4. LRU-15/A

Topping-off valves on multiplacelife rafts are used in conjunc-tion with the

1. oral Inflation tube2. hand pump3. CO2 manifold4. internal bulkheads

The LRU–13/A life raft isdesigned to hold what maximumnumber of people?

1. 132. 73. 54. 4

Life rafts that are stowedinboard on aircraft are securedto the aircraft by which of thefollowing methods?

1. A painter line2. A life line3. A securing line4. A mooring line

What is the static breakingstrength of the line used tosecure a life raft to anaircraft?

1. 10 to 20 Pounds20 to 40 pounds2.

3. 30 to 50 pounds4. 30 to 150 pounds

The LRU-14 series raft isdesigned to hold what maximumnumber of aircrew members?

1. 142. 123. 7

5-31.

5-26.

5-32.

5-27.

5-28.

5-33.

4. 4

What unique design feature doesthe LRU-15/A raft have over othermultiplace rafts?

1. It carries an outboard motor2. It is always right side up

after it’s inflated3. It has a punctureproof

flotation tube4. It can be used as a sailboat

If an LRU–14 series life raftfails to inflate with CO2, theaircrew member should be taughtto use the hand pump to inflatewhich part of the lifefirst?

1. The floor2. The main flotation3. The spray tube4. The seat

How long is the retaina LR-1 life raft?

1. 8 feet2. 6 1/2 feet3 . 5 feet4. 4 feet

raft

tube

ing line on

DELETED

Learning Objective: Recognizetypes, operating principles,design features, and maintenancerequirements of life preservers,:and identify the components,their purposes, capabilities,configurations, and lifesavingapplicatlons.

The LPU-21/P series lifepreserver is intended for use inaircraft that are equipped withejection seats.

1. True2. False

29

5-34. What is the weight of theLPU-21/P series life preserverwithout survival equipment?

1. 5.0 pounds2. 4.5 pounds3. 3 pounds4. 4 pounds

5-35. When properly inflated, theLPU-21/P series life preserverprovides the wearer with aminimum buoyancy of

1. 40 pounds2 . 60 pounds3 . 65 pounds4. 70 pounds

5-36. The LPU-21/P series lifepreserver has how many flotationchambers?

1. One2. Two3. Three4. Four

5-37. The webbing belt on the LPU-21/Pseries life preserver providesfor waist size adjustment in whatrange?

1. 28 to 34 inches2. 30 to 42 inches3. 40 to 46 inches4. 30 to 44 inches

1. 212. 293. 324. 39

5-38. Which of the following aircrewmembers would wear an LPU-25/Pseries life preserver?

1. A P-3 PPC2. An H-46 crew chief3. An F-14 pilot4. A C-130 flight engineer

5-39. Which of the following is theprimary means of inflating anLPU-23/P series life preserver?

1. The FLU-8A/P automaticinflation device

2. Pulling the beaded handles3. Firing the SEAWARS system4. Actuating the explosives

primer

5—40. How many times can the FLU-8A/Pinflator be used before it mustbe replaced?

1. One2. Two3. Three4. Four

5-41 . Which of the following lifepreservers would be used by apassenger on a cargo-typeaircraft?

1. LPU-21/P2. LPU-24/P3. LPA-24. LPP-1A

5-42. What is the only differencebetween the LPP-1 and the LPP-1Alife preservers?

1. The size2. The inflation assembly3. The shape4. The automatic inflation

device

5-43. The LPP-1/1A life preserversprovide a minimum of how manypounds of buoyancy to the user?

5-44. The LPP-1/1A adjusts to fit waistsizes in what range?

1. 28 to 40 inches2. 28 to 42 inches3. 30 to 46 inches4. 30 to 52 inches

5-45. The CO2 cylinder used with theLPP-1A has a charge of how manygrams?

1. 25 to 282. 26 to 29

28 to 313.4. 30 to 33

5-46. The protective cover used withthe LPU-30/P life preserver issupplied in how many sizes?

1. One2. Two3. Three4. Four

30

5-47. 5-53.

2

5-48.

How is the LPU-30/P lifepreserver inflated?

1. By pulling the inflationlanyard

2. By using an FLU-8A/P assembly3. By pulling the beaded handles

Life preservers that areinstalled in an aircraft aresubject to a special inspectionThis inspection must NOT exceedhow many days?

1. 142. 303. 1804. 231

Personnel issue life preserversare on a calendar/phase inspec-

5-54.

5-49.5-55.

tion cycle of how

1. 302. 603. 904. 181

A functional testlife preservers aoften?

1. Every 90 days

many days?

5-50. iS performed onminimum of how 5-56.

5-51.

2. Every 180 days3. Every third inspection4. Every fourth inspection

When performing a functional teston a life preserver, it shouldinflate fully to its designedshape in less than what maximumnumber of seconds?

1. 302. 403. 604. 90

If it is necessary to readjustthe pressure in a life preserverwhen you are doing a leak test,how many minutes should you waitafter the air supply has beenshut 0ff?

1. 32. 103. 154. 20

After the life preserver pressurehas stabilized, how many hoursmust you wait before the pressureis recorded?

1. 12.3. 34. 4

What is the maximum allowablepressure drop in an LPU-30/P lifepreserver after a period of 4hours?

1. 0.1 psi2. 0.2 psi3. 0.3 psi4. 0.4 psi

To perform the visual inspection,you would inflate the lifepreserver to how many psi?

1. 12 . 2

33.4. 4

What indication do you look forto ensure that the automaticinflation feature of a LPU-23/Plife preserver is in tact?

1. The silver indicator will bevisible

2. The firing check port will beopen

3. The silver indicator will notbe visible

4. The firing check port will beclosed

What is the service life of theFLU-8/P series automatic inflatorfrom the date of manufacture?

1. 12 months2. 24 months3. 48 months4. 66 months

DELETED

5-57.

5-52.

5-58.

31

5-59.

5—60.

5-61.

5-62.

5-63.

When performing a battery voltagetest on an LPU–24/P series lifepreserver, you would use a needletype voltage multimeter?

1. True2. False

How long should you wait for theFLU-8A/P circuit to stabilizebefore you take the voltagereadings?

1. 10 seconds2. 15 seconds3. 20 seconds4. 25 seconds

What would a reading of -12indicate when performing abattery voltage test?

1. The battery is installedbackwards

2. The battery is dead3. Both batteries are dead4. The voltage meter is on the

wrong setting

How many times do you operate thebeaded inflation handles toensure the piercing pin movesproperly?

1. Two or three2. Three or four3. Five or six4. Eight

How much pressure is applied tothe actuating lanyard of aLPP–1/1A series life preserverwhen you perform an initiationlanyard pull test?

1. 10 pounds2. 15 pounds3. 20 pounds4. 25 pounds

5-64.

5-65.

5-66.

5—67.

What is used to clean the threadson a CO2 cylinder?

1. A wire brush2. A thread chaser die3. A jeweler’s file4. A soft cloth

To ensure a firm cylinder seat,the cylinder must have a minimumof how many threads?

1. 52. 63. 74. 8

Before you replace a CO2

cylinder, you must ensure that itis no less than how many grams ofits minimum stamped weight?

1. 12. 23 . 34. 4

How much force is used to torquethe sensor plug cap on anFLU-8A/P?

1. 5 inch-pounds2. 6 inch-pounds3. 7 inch-pounds4. 8 inch-pounds

32

Assignment 6

Textbook Assignments: “Seat Survival Kit,” pages 7-1 through 7-9; and “CarbonDioxide,” pages 8-1 through 8-5.

Learning Objective: Identify,inspect, and maintain the RSSK-8seat survival kit.

6-1.

6-2.

6-3.

6-4.

6-5.

Which portion of the RSSK-8container houses the emergencyoxygen supply?

1. The seat cushion2. The upper container3. The survival kit unit4. The lower container

The release handle is located onwhich area of the RSSK-8?

1. The rear left side2. The forward left side3. The forward right side4. The rear right side

Oxygen from the emergency oxygensystem is prevented from flowinginto the aircraft O2 system bythe

1. aircraft O2 pressure2. poppet valve3. check valve in the O2 mask4. check valve in the O2 line

If the automatic actuationlanyard falls to actuate theemergency oxygen system, theaircrew member can operate itmanually by pulling the

1. yellow “O” ring2. green knob3. green ring4. yellow release handle

A hard landing would warrantwhich of the followinginspections on a seat kit?

1. A conditional2. An SDLM3. A turnaround4. A postflight

6-6.

6-7.

6-8.

6-9.

6-10.

Which of the following activitiesis responsible for doing a 7- or14-day inspection on a survivalkit installed in an aircraft?

1. QA division2. Aircraft division3. Aviator’s equipment branch

When performing a daily inspec-tion on an RSSK-8, you discoverthe seal decal is torn. Whataction, if any, would you take?

1. Notify maintenance control2. Replace the torn decal3. Notify QA4. None

On the RSSK-8 survival kit,similar parts from kits made bydifferent manufacturers areinterchangeable.

1. True2. False

What is the maximum time that canelapse between phase inspectionson a seat kit?

1. 91 days2. 182 days3. 225 days4. 231 days

To perform the swaged ball pulltest, the swaged ball shouldwithstand a pull force of howmany pounds?

1. 502. 1003. 1504. 200

33

6-11.

6-12.

6-13.

6-14.

6-15.

6-16.

When performing the swaged ballpull test, you must ensure thatthe links and clevis are notpulled from the housing more thanwhat maximum distance?

1. 1/2 in2. 1 in3. 1 1/2 in4. 2 in

What is the ideal temperature inan oxygen shop when a functionaltest is performed on a seat kit?

1. 65°F2. 70°F3. 72°F4. 75°F

To perform a functional test on aseat kit, the O2 system shouldhave a pressure reading of howmany psi?

1. 1,200 to 1,4002. 1,400 to 1,6003. l,600 to 1,8004. 1,800 to 2,000

When you test the manualemergency oxygen release handle,what should be the disengagementforce for the handle?

1. 5 to 20 pounds2. 10 to 30 pounds3. 20 to 40 pounds4. 30 to 50 pounds

When testing the relief valve onthe RSSK-8 emergency O2 system,at what pressure range should thevalve unseat?

1. 10 to 302. 70 to 903. 90 to ll04. 120 to 140

psipsipsipsi

The relief valve should reset ata minimum of how many psi?

1. 302. 903. ll04. 120

6-17.

6-18.

6-19.

6-20.

6-21.

6-22.

6-23.

Purging the emergency O2 systemis required when the system meetswhich of the following criteria?

1. Falls below 5 psi2. Falls below 15 psi3. Has remained empty for less

than 2 hours4. Has remained empty for more

than 2 hours

To release pressure in the oxygenbottle before purging, thepressure should be releasedthrough the filler valve.

1. True2. False

To purge an oxygen system, youshould use nitrogen that isheated to a temperature range ofhow many degrees?

1. 180° to 200°F2. 220° to 230°F3. 230° to 266°F4. 260° to 276°F

When chargingfilling stageleast

1. 5 minutes2. 2 minutes3. 3 minutes4. 4 minutes

an O2 system, eachshould take at

A cooling period of how long isrequired between each fillingstage?

1. 1 minute2. 2 minutes3. 3 minutes4. 4 minutes

If a seat kit is to be stored, apressure of how many psi shouldremain in the O2 system?

1. 2002. 5003. 9004. 1,200

When recharging a seat kit, howmany psi of oxygen is suppliedbetween stages 3 and 4?

1. 1002. 2003. 3004. 400

34

6-24.

6-25.

6-26.

6-27.

6-28.

6-29.

6-30.

Learning Objective: Inspect andrecharge CO2 cylinders.

What color, if any, is CO2?

1. Pale gray2. Dark gray3. Pale blue4. Colorless

A standard supply cylinder willcontain how many pounds of CO2?

1. 102. 403. 504. 80

In its gaseous form, CO2 is howmany times heavier than air?

1. 1.502. 1 .533. 1.604. 1.63

At a temperature of 72°F, CO2 gascan be converted into a liquid byapplying a pressure of how manypsi?

1. 4002. 5003. 6004. 700

Depending on temperature andpressure, CO2 can take on howmany different forms?

1. One2. Two3. Three4. Four

In its dry ice form, CO2 has whattemperature?

1. -32°F2. -40°F3. -90°F4. -110°F

What effect does 3 percent of CO2

in the atmosphere have on thehuman body?

1. It causes distorted vision2. It causes panting3. It causes unconsciousness4. It doubles a person’s

breathing effort

6-31.

6-32.

6-33.

6-34.

6-35.

6-36.

If a person breathed air that had10 percent CO2 what would be theeffect on the human body?

1. It would cause blurred vision2. It would cause panting3. It would cause

unconsciousness4. It would cause marked

distress

If a person has been overcome byCO2, which of the following firstaid techniques should be used?

1. Giving artificialresuscitation

2. Administering oxygen3. Keeping them warm4. All of the above

A CO2 recharge unit will pump CO2

in which of the following forms?

1. Liquid or gas2. Liquid only3. Gas only4. Liquid, gas, or solid

A standard CO2 supply cylinderwill contain approximately howmany pounds of liquid CO2 at atemperature of 70°F?

1. 122. 283. 384. 50

The warmer the supply cylinder,the more efficient will be thetransfer operation.

1. True2. False

Why is it a recommended procedureto invert the CO2 supply cylinderwhen recharging?

1. It will prevent the hosefitting from freezing shut

2. The CO2 will remain cooler,allowing it to transferfaster

3. It allows the syphon tube toaccept the gas

4. It allows the syphon tube toaccept the liquid

35

6-37. A hydrostatic test on a CO2

supply cylinder is good for whatmaximum period of time?

1. 5 years2. 7 years3. 3 years4. 4 years

6-38. DELETED 2

6-39. CO2 cylinders must be paintedwhat color?

1. Green2. Black3. Gray4. White

6-40. All markings on a CO2 cylindermust be what color?

1. White2. Gray3. Yellow4. Black 1. 0.25 lb

2. 0.50 lb3. 0.75 lb4. 1.00 lb

6-41. Information on a CO2 cylindermust include which of thefollowing?

1. Tare weight2. Gross weight3. CO2 weight4. All of the above

6-42. If a CO2 cylinder has a dentexceeding 1/16 inch in depth,what should you do?

2.1. Declare it RFI and use it

Reject it and return it tosupply

3. Declare it useful until thenext hydrostatic test date

4. Return it to the IMA forfurther inspection

6-43. What action would you take if aCO2 cylinder showed evidence thatit had been in a fire?

1. Refurbish it2. Recharge and return it as RFI3. Return it to supply4. Forward it to NAEC for

disposition

6-44. To properly record the weight ofa CO2 cylinder, you must use ascale that is graduated in

1. 1/100 lb2. 1/1000 lb3. 1/100 oz4. 1/1000 oz

6–45 . What is the TARE weight of a CO2

cylinder?

1. Empty weight with the valveand cable assembly

2. Empty weight of the cylinderonly

3. Full weight with the valveand cable assembly

4. Full weight of the cylinderonly

6-46. What is the weight of the CO2

charge for an LR-1 life raftcylinder?

6-47. If the cylinder being rechargedceases to gain weight, one of thereasons may be the CO2 in thesupply cylinder is less than whatminimum weight?

1. 20 lb2. 15 lb3. 10 lb4. 5 lb

Learning Objective: Recognizehow a CO2 transfer pump iSmaintained.

6-48. How often should the oil bechecked in the CO2 transfer pump?

1. Daily2. Weekly3. Biweekly4. Monthly

36

6-49. How often should the idler shaftin the CO2 transfer pump belubricated?

1. Weekly2. Monthly3. Every 6 months4. Yearly

6-50. What lubricant should be used onthe idler shaft?

1. Heavy duty cup grease2. 10-10 oil3. 1O-30 oil4. Light cup grease

6-51. The piston rod should belubricated with

6-52. How often, if ever, is thecommutator lubricated on a CO2

transfer unit?

1. Monthly2. Every 6 months3. Yearly4. Never

6-53. How often, if ever, should thecrankcase be serviced?

1. Yearly2. Every 2 years3. Every 3 years4. N e v e r

1. SAE 40 oil2. Vaseline3. light cup grease4. heavy cup grease

37

Assignment 7

Textbook Assignment: “Sewing Machines.” Pages 9-1 through 9–39.

7-1.

7-2.

7–.3.

7–4.

7-5.

Learning Objective: Identifytypes, operating characteristics,components, and functions ofsewing machines used by the PR.

Sewing machines are classified ashow many basic types?

1. One2. Two3. Three4. Four

Which of the following parts of asewing machine forms the stitch?

1. Rotary hook2. Oscillating shuttle3. Both 1 and 2 above4. Thread take-up lever

Which of the following types ofstitches is most commonly usedand made by sewing machines?

1. Lock stitch2. Chain stitch3. Compound stitch4. Either 2 or 3 above,

depending on the model ofmachine

Sewing machines have how manybasic parts?

1. One2. Two3. Three4. Four

Material that is being sewn on asewing machine is held in posi-tion byparts?

1. The2. The3. The4. The

which of the following

needle barpressure footfeed dogspressure bar

7-6.

7-7.

7-8.

7–9.

7-10.

7-11.

Which of the following machinesis classified as an oscillatingmachine?

1. 211 w 1552. 111 w 1513. 111 w 1554. 31-15

What is the recommended stitchesper minute for the 31-15 machine?

1. 1,5002. 2,0003. 2,2004. 1,800

What is the stitch range of the31-15 machine?

1. 5-32 spi2. 7-32 Spi3. 3-15 spi4. 4–22 spi

The 31–15 sewing machine can sewcanvas up to a maximum of howmany ounces?

1. 62 . 23. 84. 4

A sewing machine that is inconstant use should be oiled howoften?

1. Once a day2. Twice a day3. Everytime the bobbin is

changed4. Every hour

What type oil is recommended foroiling a sewing machine?

1. 10W mineral2. 20W castor base3. 3-in-14. SAE 30

38

7-12.

7-13.

7-14.

7-15.

7-16.

How much oil is used on each 7-17.oiling point on a 13-15 machine?

1. One drop2. Two drops3. Three drops4. Until the oil wick is

saturated

What is the proper class andvariety of the needle used in the31-15 machine?

1. 7 x 172. 16 x 873. 31 x 154. 87 x 16

A properly timed needle bar on a31-15 sewing machine will havethe needle bar located so thatthe point of the shuttle will behow far above the eye of theneedle on its upstroke?

1. 1/16 in2. 1/32 in3. 1/4 in4. 1/2 in

Prior to making any adjustmentson a sewing machine, a good ruleto follow is to do which of thefollowing?

1. Set the stitch length to 0spi

2. Check the troubleshootingchart

3. Set the stitch length to 8spi

4. Remove the belt from theclutch pulley

When the point of the needlereaches the material, the feeddogs should be at what position?

1. On the down stroke and evenwith the throat plate

2. One full tooth above thethroat plate

3. On the up stroke and evenwith the throat plate

4. One full tooth below thethroat plate

7-18.

7-19.

7-20.

7-21.

When adjusting the feed eccentricon the 31-15, the stitchregulator should be set at itslowest position. This is done sothe machine will do which of thefollowing?

1. Form its shortest stitch2. Prevent any loose movement in

the feed eccentric3. Form its longest stitch4. Prevent the needle from

hitting the throat plate

What is the recommended settingof the feed dogs for lightweightmaterial?

1. One full tooth above thethroat plate

2. Slightly more than oneabove the throat plate

3. Even with the throat p4. Slightly less than one

above the throat plate

When selecting a needle to

tooth

latetooth

beused on cloth, which of thefollowing type points would youselect?

1. A diamond-shaped point2. A sharp round point3. A triangle point4. A half-round point

Why shouldn’t a cutting pointneedle be used when sewing canopyfabric?

1. It will break the top thread2. It will break the bobbin

thread3. It will cut the warp and

filler threads4. It will not make a lock

stitch

What, if anything, is the purposeof the grooves on both sides of a16 x 87 sewing machine needle?

1. They prevent the hook fromstriking the needle

2. They tell the class andvariety of the needle

3. They serve no purpose4. They allow the thread to fall

back into the needle when itenters the material

39

7-22.

7-23.

7-24.

7-25.

7-26.

7-27.

7-28.

What determines the size of aneedle?

1. Diameter of the needle2. Needle eye size3. Both 1 and 2 above4. Thread groove size

What determines the correct sizeof needle to be used on aproject?

1. The type of thread2. The size of thread3. The material4. All of the

What size needyou were goingof nylon using

1. 182. 203. 214. 24

to be sewnabove

le would you use ifto sew five pliestype “E” thread?

What size needle should you useto sew elastic webbing?

1. 18202.

3. 224. 24

When the bobbin is properlythreaded into the bobbin case,the bobbin will turn clockwisewhen the free end of the threadis pulled.

1. True2. False

What should you do to prevent theneedle thread from fouling whenyou start to sew?

1. Backstitch 1/4 in2. Backstitch 1/2 in3. Hold both threads until you

have made two or threestitches

4. Overstitch 1 in

When regulating the tension onthe needle thread, you mustremember that the

1. needle bar must be all theway down

2. presser foot must be up3. needle bar must be all the

way up4. presser foot must be down

7-29.

7-30.

7-31.

7-32.

7-33.

7–34.

A properly formed stitch willhave the threads locking in whof the following positions?

1. In the bottom ply of mater2. In the center of the

thickness of material3. In the top ply of material

What is used to regulate thepressure on the material?

1. The pressure-regulatingthumbscrew

ich

ial

2. The pressure-regulating hexnut

3. The pressure-regulatingspring

4. The pressure-regulating disc

If the thread take-up spring isnot correctly set, you shouldloosen the setscrew in the arm ofthe machine and turn the tensionadjusting stud in which directionto lessen the movement of thespring?

1. To the right2. To the left3. Toward the front4. Toward the rear

The class 7-33 sewing machine isintended for what type of work?

1. Sewing light to medium canvas2. Sewing light canvas only3. Sewing medium canvas4. Sewing heavy canvas

What is the difference betweenthe 7-31 and the 7-35 machines?

1. The 7-23 has a clutch on thebalance wheel

2. The 7-31 makes a zigzagstitch

3. The 7-31 has a clutch on thebalance wheel

4. The 7–35 is a heavy weightmachine and the 7-31 is amedium weight machine

To remove the bobbin from the7–33 sewing machine, you must usethe bobbin case release spring.

1. True2. False

40

7-35.

7-36.

7-37.

7-38.

7-39.

7-40.

When replacing the bobbin in the7-33 sewing machine, you shouldleave about how many inches ofthread hanging free from theshuttle?

1. 2 1/22. 23. 34. 4

The class 111 sewing machines arecapable of sewing up to how manystitches per minute?

1.2.3.4.

Whiwou

2,0002,2003,0003,500

ch of the following machinesld you use for binding heavy

materials?

1. 31-152. 111 W 1543. 31-TB4. 111 W 150

Which of the following parts of aclass 111 sewing machine re-engages the needle with the hookdriving assembly after clearing athread jam?

1. Needle-deflecting hook washer2. Rotary hook assembly3. Rotary hook saddle4. Safety-clutch lock stud

What is the first step in timinga 111 W series sewing machine?

1.2.3.4.

Set the eccentric on 0 psiSet the needle barLine up the timing marksLoosen the needle bar pinchscrew

class 111 W 151 sewingThemachine has what type of feedingaction?

1. Needle drop and alternatingpresser foot

2. Needle drop3. Compound feed only4. Vibrating drop

7-41.

7-42.

7-43.

7-44.

7-45.

7-46.

7-47.

To set a needle bar that has notiming marks, you must first setthe feed eccentric to how manystitches per inch?

1. 022.

3. 64. 8

The eye of the needle should behow far below the sewing hookwhen it is set properly?

1. 1/8 in2. 1/16 in3. 3/32 in4. 5/16 in

When centering the feedingaction, what is the distancebetween the needle bar and thepressure bar?

1. 1/16 in2. 7/32 in3. 3/32 in4. 17/32 in

The 111 W 152 sewingalternating pressersof how many inches?

1. 1/22. 2/33. 3/84. 5/16

machine haswith a lift

The 111 W 154 sewing machine hasa presser foot lift of how manyinches?

1.2.3.4.

On awhatbobb

1.2.3.4.

The

1/22/33/817/32

111 W class sewing machine,would indicate that thein case needs oil?

The oil wickThe green felt padThe black felt padThe oil reservoir

needle that is used in arotary sewing machine has howmany parts?

1. 52. 63. 74. 8

41

7-48. How is the bobbin thread tension

7-49.

7-50.

7-51.

7-52.

7-53.

7-54.

regulated on a rotary type sewingmachine?

1. A thumb screw on the machineface

2. A small screw on the outsideof the bobbin case

3. An adjusting nut on thebobbin case

4. A small screw on the feedeccentric

What feature on the 211 W 151sewing machine prevents damage tothe sewing hook?

1. An automatic safety gib2. A hook gib3. A safety pulley4. A safety clutch

What is the maximum speed of the211 W 151 sewing machine?

1. 3,000 rpm2. 3,500 rpm3. 3,800 rpm4. 4,000 rpm

What needle is used in the 211 W151 machine?

1. 135 x 172. 135 x 73. Either 1 or 2 above,

depending on the lift4. 16 x 87

With 1/4 inch clearance under thepresser foot, what needle is usedon a 211 W 151 sewing machine?

1. 135 x 222. 16 X 873. 135 x 74. 1.35 x 17

What needle would you use with aclearance of 3/8 inch?

1. 1.35 x 222. 16 x 873. 135 x 74. 135 x 17

When setting the needle into a211 w 151, which direction shouldthe long thread groove face?

1. Right2. Aft3. Forward4. Left

7-55.

7–56.

7-57.

7-58.

7-59.

7-60.

7-61.

When setting the relativeposition of the presser andneedle bar on a 211 W 151machine, how much clearance mustbe maintained?

1. 3/4 in2. 17/32 in3. 3/16 in4. 3/32 in

A properly set feed dog on a211 W 151 machine will show afull tooth above the throat platewhen the feed dog is at itslowest position.

1. True2. False

The hook saddle on a 211 W 151machine is lubricated by which ofthe following methods?

1. A felt pad2. An oiling wick3. An oil reservoir4. A wool pad

Which of the following sewingmachines makes a zigzag stitch?

1. 142 W 1512. 143 W 23. 142 W 154. 111 w 143

What is the maximum throw of the143 W 3 needle bar?

1. 9/16 in2. 7/16 in3. 5/16 in4. 3/16 in

What is the maximum throw of theneedle bar on a class 143 W 2sewing machine?

1. 3/8 in2. 5/16 in3. 1/4 in4. 3/16 in

Which direction does the longthread groove face on the 143 W 3sewing machine?

1. Forward2. Aft3. Left4. Right

42

7-62. What type of stitch is formed by 7-63. What will happen if you turn thea model 99R-3 sewing machine? zigzag regulating knob clockwise

1.as far as it will go on a model

302 99R sewing machine?2. 3043. 306 1. It will make a wider stitch4. 308 2. It will make a straight

stitch3. It will sew backwards4. It will make a narrow stitch

43

Assignment 8

Textbook Assignment: “Fabrication and Manufacture.” Pages 10–1 through 10-30.

Learning Objective: Use correctterminology when discussing yarnsand fabrics.

8-1.

8-2.

8-3.

8-4.

8–5.

What is the basic unit used inthe fabrication of textile yarnsand fabrics?

1. Staples2. Fiber3. Yarn4. Fillers

What is the edge of materialcalled that has a woven finish toprevent raveling?

1. The material edge2. The manufactured edge3. The selvage edge4. The finished edge

Threads that run lengthwise andparallel to the selvage edge arecalled what?

1. Warp thread2. Filling thread3. Locking thread4. Basic thread

Which of the following is anothername used for filling threads?

1. Woof2. Pick3. Weft4. All of the above

Bias cuts are made at what angleto the filling threads?

1. 180°2.3. 90°4. 45°

8-6.

8-7.

8-8.

8-9.

8-10.

8-11.

Why iS a bias cut used tomanufacture a parachute?

1. To save material2. To prevent tearing be

two sections3. To provide elasticity4. All of the above

What name is given to therequired to break material

1. Breaking strength2. Tensile strength3. Warp strength4. Filler strength

tween

force?

What determines the weight ofcloth?

1. Ounces per running yard2. Ounces per square foot3. Ounces per square yard4. Ounces per running foot

The definition of cloth is anymaterial that is over how manyinches from selvage edge toselvage edge?

1. 102. 123. 144. 18

Which of the following is a basicweave?

1. Plain2. Twill3. Both 1 or 2 above4. Warp

Which type of weave gives thesmoothest finish and iS theeasiest to manufacture?

1. Twill2. Plain3. Warp4. Filling

25°

44

8-12.

8-13.

8-14.

8-15.

8-16.

8-17.

8-18.

Heat is less damaging to cottonthan it is to synthetic fibers.

1. True2. False

At approximately 700°F, Nomexfabric will begin to do which ofthe following’?

1. Burn2. Melt3. Char4. Disintegrate

Webbings arethat is lessfrom selvageedge?

1. 62. 83. 104. 12

defined as materialthan how many inchesedge to selvage

Textile tapes can weigh up to howmany ounces per square yard?

1. 32. 103. 154. 20

Depending on the project, eright- or left-twist threadbe used on a sewing machine

1. True2. False

8-19.

8-20.

8-21.

ither can

8-22.

Learning Objective: Discusscharacteristics? specifications,and care of fabrics.

An ideal storage area for textilematerial would be dry and out ofdirect sunlight, with atemperature of how many degrees?

1. 50°F2. 60°F3. 70°F4. 80°F

Exposure to which of thefollowing elements would causethe most serious damage to nylonmaterial?

1. Mildew2. Direct sunlight3. Fresh water4. Salt water

8-23.

8-24.

Which of the following factorsis/are affected by the airpermeability in a parachuteassembly?

1. Opening time2. Opening force3. Stability4. All of the above

A length of nylon cord, which is100 feet long and has anelongation of 10%, can bestretched to what maximumdistance without breaking?

1. 110 ft2. 120 ft3. 130 ft4. 140 ft

What does the term “moistureregain” mean when referring tofibers?

1. The percentage of staticelectricity it absorbs fromthe air

2. The percentage of moisture itabsorbs from the air

3. The percentage of staticelectricity it repels

4. The percentage of moisture itrepels

Military specifications forparachute materials require that,after 50 hours of exposure tosunlight, parachute fabricsshould not lose more than whatpercent of its original strength?

1. 10%20%2.

25%3.4. 50%

What percentage can nylon bestretched without being damaged?

1. 5 to 25%2. 10 to 20%3. 15 to 30%4. 18 to 40%

What is the percentage ofelasticity in nylon?

1. 70%2. 75%3. 80%4. 100%

45

8-25.

8-26.

8-27.

8-28.

8-29.

8-30.

8-31.

Nylon has what percent ofmoisture regain?

1. 2.52. 3.23. 4.24. 5.5

What is the melting point ofnylon material?

1. 382°F2. 482°F3. 540°F4. 600°F

Learning Objective: Identify anddiscuss special hand tools,grommets, and fasteners.

When installing the chuck and dieinto a grommet press, the chuckis the upper tool and the die isthe lower.

1. True2. False

A properly set chuck and die willhave a clearance of how manyinches?

1. 1/82. 1/323. 1/24. 3/4

A carpenter’s square has armmeasurements of how many inches?

1. 12 and 242. 14 and 243. 16 and 244. 18 and 24

Which of the following tools isbest suited for making holes inmaterial that will use snaps orspeedy rivets as

1. A hand press2. An awl3. A star punch4. A hot iron

fasteners?

Which of the following sizes ofgrommets is the smallest?

1. 12. 23. 34. 4

8-32.

8-33.

8-34.

8-35.

8-36.

8-37.

8-38.

When setting a grommet, thecollar size must match the punchsize.

1. True2. False

When using a grommet set toinstall a grommet, what shouldyou use to strike the punch?

1. A ballpeen hammer2. A rawhide mallet3. A setting maul4. A hand press

What is the most common typefastener used on clothing?

1. Velcro2. Three-way locking3. Glove fastener4. Curtain fastener

Which of the following typefasteners would you use if youneeded extra security?

1. Segma Dot2. Durable Dot3. Glove4. Three-way locking

Three-way locking snaps aresupplied in how many sizes?

1. One2. Two3. Three4. Four

Curtain type fasteners areavailable in how many sizes?

1. One2. Two3. Three4. Four

Which of the following methods isused to clean grease and dirtfrom a slide fastener?

1. MEK2. Toluene3. Soap and water4. Stoddard solvent

46

8-39.

8-40.

8-41.

8-42.

8-43.

8-44.

After cleaning a slide fastener,which of the following lubricantsshould you use to lubricate it?

1. Oil2. Graphite3. Either 1 or 2 above,

depending on the material4. Silicone gel

What action should you take ifyou discover that the bead on aslide fastener is torn?

1. Replace the complete slidefastener

2. Replace the bead3. Replace only the broken side4. Repair- the bead

To shorten an interlocking slidefastener, the chain should be howmuch shorter than the opening inthe material?

1. 1/2 in2. 3/4 in3. 1 in4. 1 1/2 in

Slide fasteners are available inhow many types?

1. One2. Two3. Three4. Four

Slide fasteners are supplied inhow many sizes?

1. Six2. Five3. Three4. Four

What grade of slide fastener ismade from brass?

1. I2. II3. III4. IV

Learning Objective: Identifyhand-sewn seams and stitches.

8-45.

8-46.

8-47.

8-48 .

8-49.

8-50.

Why should you use yellow beeswaxon hand sewing thread?

1. It contains no oil2. To prevent fraying and

untwisting3. Both 1 and 2 above4. To keep the thread from

weakening

Which of the following stitchesis used to temporarily hold aseam together?

1. Overthrow stitch2. Baseball stitch3. Running stitch4. Basting stitch

Which of the following stitchesshould you use if a sewingmachine is not available?

1. Baseball stitch2. Overthrow stitch3. Running stitch4. Lock stitch 301

Which of the following stitchesis used to sew an eyelet onto aparachute container?

1. Baseball stitch2. Overthrow stitch3. Running stitch4. Eyelet stitch

Which hand stitch should you usewhen a neat appearance isnecessary to the seam?

1. Hidden stitch2. Lock stitch3. Baseball stitch4. Basting stitch

What type of needle is used tomake a hidden stitch?

1. 1 1/2-inch curved2. 2-inch straight3. 1 1/2-inch straight4. 2 1/2-inch curved

Learning Objective: Identify anddiscuss machine-sewn stitches andseams.

47

8-51. Machine-sewn seams have which ofthe following advantages overhand-sewn seams?

1. Uniformity of tension2. Speed3. appearance4. All of the above

8-52. Which of the following stitchesis a U.S. standard lock stitch?

1. 3012. 3023. 3034. 304

8-53. There are how many classes ofseams?

1. One2. Two3. Three4. Four

8-54. What type of seam would you makeif you laid one piece of materialon top of another and ran a rowof stitches down one side? 2.

1. A lapped seam2. A superimposed seam3. A bound seam4. A edge finishing seam

8–55. If your thread should break whilesewing a seam, you should startsewing again

1. 1/2 inch behind the break2. 1/8 inch behind the break3. 3/4 inch behind the break4. 1 inch behind the break

Learning Objective: Select thecorrect knot for variousapplications in survivalequipment work.

8-56. What is the simplest knot used tojoin two cords together?

1. Bowline knot2. Overhand knot3. Square knot4. Binders knot

8-57. Which of the following knots isthe most common used to join twocords together?

1. Binders2. Square3. Surgeons4. Half-hitch

8-58. What knot would you use for asafety tie on ripcord pins?

1. OverhandSquare

3. Half-hitch4. Bowline

8–59. Which of the following knots isused to secure the parachutesuspension lines to the connectorlinks?

1. Clove hitch2. Sheepshank3. Bowline4. Binder

48

Assignment 9

Textbook Assignment: “Oxygen Components Test Stands.” Pages 11-1 through 11-21.

9-1.

9-2.

9-3.

9-4.

9-5.

Learning Objective: Recognizethe properties of oxygen, itsdensity and state according totemperature/pressure conditions,and the adverse effects caused byoxygen deficiency.

At what minimum altitude is itnecessary to use a positivepressure breathing regulator?

1. 18,000 ft2. 20,000 ft3. 25,000 ft4. 35,0O0 ft

A demand (inhalation) regulatorCANNOT supply enough oxygen forthe user above what maximumaltitude?

1. 32,000 ft2. 33,000 ft3. 35,000 ft4. 43,000 ft

What term is used to describe thecondition when the body receivesan insufficient amount of oxygento function properly?

1. Anoxia2. Aphyxia3. Hypoxia4. Suffocation

Which of the following termsrefers to a complete lack ofoxygen to the body?

1. Anoxia2. Asphyxia3. Hypoxia4. Suffocation

The atmosphere contains aboutwhat percentage of oxygen byvolume?

1. 10%2. 21%

33%3.4. 23%

9-6.

9-7.

9-8.

9-9.

9-10.

9-11.

Combustion is a form of rapidoxidation. Which of thefollowing examples represents}slow oxidation?

1. Rusting iron2. Paint turning brittle3. Alcohol turning into vinegar4. All of the above

The atmosphere contains aboutwhat percentage of nitrogen byvolume?

1. 21%2. 23%3. 33%4. 78%

What is the weight of 2 gallonsof liquid oxygen?

1. 17.00 lb2. 19.08 lb3. 21.00 lb4. 21.08 lb

Liquid oxygen changes to gaseousoxygen at an expansion ratio of

1. 520 to 12. 682 to 13. 862 to 14. 986 to 1

With an applied pressure of 750psi, at what temperature willoxygen begin to take on itsliquid form?

1. -147°F2. -182°F3. -280°F4. -297°F

Oxygen procured by the Navy andtested at a temperature of 70°Fmust have a purity of 99.5% and awater content of no more than howmany milligrams per liter?

1. 0.012. 0.023. 0.034. 0.04

49

Learning Objective: Recognizethe systems and the operation ofthe 1172AS1OO test stand.

9-12.

9-13.

9-14.

9-15.

9-16.

9-17.

What is used as the pressuresource on the 1172ASI00 teststand?

1. Oxygen2. Helium3. Nitrogen4. Argon

The 1172AS1O0 test stand canevaluate items under test ataltitudes of up to how many feet?

1. 50,0002. 75,0003. 100,0004. 150,000

How many on-off valves areincorporated into this teststand?

1. One2. Two3. Three4. Four

The reference pressure selectorvalve has how many operatingpositions?

1. One2. Two3. Three4. FOur

Which of the following valvesindicates inches of watersuction?

1. Reference pressure-selectorvalve

2. Pressure-selector valve3. Leakage-selector valve4. Flow–selector valve

What is the principle ofoperation of a Vol-O-Flo element?

1. Flow pressure2. Flow suction3. Flow restriction4. Flow detection

9-18.

9-19.

9-20.

9-21.

9-22.

9-23.

Where are the Vol-O-FlO elementsinstalled on the 1172AS100 teststand?

1. On control valves andselector valves

2. Between certain controlvalves and their indicatingmanometers

3. On certain on-off valves andcontrol valves

4. Between selector valves andtheir indicating manometers

How many Vol-O-Flo elements areincorporated into the 1172AS100test stand?

1. One2. Two3. Three4. Four

Which of the following valvesallows ambient air pressure intothe chamber through the inputVol-O-Flo element?

1. System bleed valve2. Chamber bleed valve3. Output valve4. Input valve

Which of the following valves hasa manometer?

1. Flutter dampener2. Chamber bleed3. Output4. System bleed

Why is the vent ambient valveconsidered an economizer valve?

1. It conserves ambient air2. It is used at sea level3. It is a nonmeasuring valve4. It conserves nitrogen

The proper way to use the shut-off valve is to open it fully,then turn it back how far?

1. 1/8 turn2. 1/4 turn3. 1/2 turn4. 3/4 turn

50

9-24.

9-25.

9-26.

9-27.

9-28.

9-29.

9-30.

The high pressure regulator ofthe 1172AS1OO test stand suppliesgas to a system from a minimumpsig to the maximum psig of thesupply cylinder used. The gas isregulated at what minimum psig?

1. 1002 1503. 2004. 250

What is the range of the inputpressure gauge?

1. 0 to 160 psi2. 0 to 200 psi3. 0 to 2,000 psi4. 0 to 3,000 psi

What is the range of theregulated low-pressure gauge?

1. 0 to 160 psi2. 0 to 200 psi3. 0 to 2,000 psi4. 0 to 3,000 psi

What is the range of thepressure/suction manometer?

1. -3.5 to +20.0) in H2O2. -5.5 to +20.0 in H2O3. -9.5 to +22.0 in H2O4. -12.0 to +26.0 in H2O

What is the range of therange leakage rotameter?

1. 20 to 200 ccm2. 20 to 2,000 psig3. 200 to 2,000 ccm4. 200 to 2,000 psig

high

Which of the following formulasis correct?

1. 10 ccm = 1 LPM2. 100 ccm = 1 LPM3. 1,000 ccm = 1 LPM4. 10,000 ccm = 1 LPM

The overboard leakage rotameteris calibrated at 14.7 psig withan ambient air temperature of howmany degrees?

1. 60°F2. 70°F3. 75°F4. 80°F

9-31.

9-32.

9-33.

9-34.

9-35.

9-36.

The vacuum pump supplied with the1172AS100 test stand has thecapability of evacuating thechamber at a rate of 22.5 cubicfeet per minute at an altitude ofhow

1.2.3.4.

Howthefor

many feet?

43,60045,60051,60054,600

many prongs are required onelectrical connection plugthe vacuum pump on the

1172AS100 test stand?

1. Two only2. Two or three3. Three only4. Four

Learning Objective: Identify themaintenance procedures on the1172AS100 test stand.

What is the specific gravity ofthe fluid that is used to fillthe pressure suction manometer?

1. 1.02. 1.33. 1.74. 1.9

When mixing manometer fluid, theratio should be 1 part of merianD-2930 to how many parts ofdistilled water?

1. 0.12. 1.03. 10.04. 100.0

What color manometer fluid isused in themanometer?

1. Green2. Red3. Yellow4. Blue

What is the

pressure suction

gauge guard cutoffpressure for the regulated low-pressure gauge?

1. 100±5 psig2. 145±5 psig3. 150±5 psig4. 170±5 psig

51

9-37. When performing the altitudechamber and suit simulator tankinward leakage test, you mustascend to 52,000 feet andstabilize for 2 minutes. What isthe allowable altitude drop in 20minutes?

1. 1,000 ft2. 2,000 ft3. 3,000 ft4. 4,000 ft

9-38. How often are pressure leakagetests performed on the 1172AS100test stand?

1. Daily2. Weekly3. Biweekly4. Monthly

Learning Objective: Identify theoperating characteristics andmaintenance requirements of the59A120 liquid oxygen convertertest stand.

9-39. Which of the following teststands is used to test LOXconverters?

1. OTS 5652. LQTS 5653. 1172AS1004. 59A120

9-40. The bell jar assembly on theliquid oxygen converter teststand is used to test items thathave more than one area ofpossible leakage.

1. True2. False

9-41. When it is operating properly,the relief valve on the bell jarassembly has a range of how manypsig?

1. 3 to 52. 5 to 153. 10 to 154. 15 to 30

9-42. The relief valve on the bell jarassembly is leaktight at how manypsi?

1. 52. 23. 34. 4

9-43. At what pressure does the reliefvalve on the bell jar start torelieve pressure?

1. 5 psi2. 10 psi3. 15 psi4. 20 psi

9-44. The converter section of the teststand is protected by the reliefvalve (RV-11). This valve is setto relieve pressure at how manypsig?

1. 152. 503. 1004. 110

9-45. The differential pressure gauge(DF-1) has a range of how manyinches of water pressure?

1. -10 to +502. -50 to +1003. 0 to 1004. 0 to 150

9-46. How many linear flow elements areincorporated into the 59A120 teststand?

1. Five2. Six3. Three4. Four

9-47. What is the range of the supplypressure gauge on the 59A120 teststand?

1. 0 to 1,000 psig2. 0 to 2,000 psig3. 0 to 3,000 psig4. 0 to 4,000 psig

9-48. The adjustable regulator (R-1) ispreset to deliver how muchpressure to the test standthrough the oxygen supply valve?

1. 90 psig2. 160 psig3. 180 psig4. 300 psig

52

9-49.

9-50.

9-51.

9-52.

9-53.

9-54.

Which of the following pressuregauges indicates the pressureapplied to the item under test?

1. PG-12. PG-23. PG-34. PG-4

Relief valve V-4 preventsexcessive pressure buildup in thetest stand. At what pressure isthis valve leaktight?

1. 90 psig2. 120 psig3. 140 psig4. 160 psig

Relief valve V-4 is set torelieve pressure at how manypsig?

1. 902. 1203. 1604. 180

Linear flow element NIP-3measures flOW rates of how manyliters per minute?

1. 0-00.25 LPM2. 0-1.0 LPM3. 0-50 LPM4. 0-150 LPM

The 59A120 test stand iscalibrated by the on-sitemetrology calibration team aminimum of how often?

1. Once a month2. Every 6 months3. Yearly4. Every other year

When setting the oxygen pressureregulator, a minimum of how muchpressure is applied to theregulator?

1. 300 psig2. 1,000 psig3. 1,800 psig4. 2,000 psig

How much pressure is set on thepressure regulator (R-1)?

1. 110 psig2. 120 psig3. 160 psig4. 180 psig

9-56. When testing the 59A120 teststand for overall leaking, therelief valve (RV–11) should beset to unseat at how many psig?

1. 1102. 1203. 1304. 140

9-57. When performing the overallleakage test, any leaking in thesystem is indicated by a drop inpressure on the test pressuregauge (PG-1). This pressure dropshould not be more than how much?

1. 5 psig in 5 min2. 5 psig in 10 min3. 10 psig in 15 min4. 10 psig in 10 min

9-58. When the bell jar assembly istested for leakage, the pressuredrop indicated on thedifferential pressure gaugeshould not be more than 2 inchesof H2O in how many minutes?

1. 52. 103. 124. 15

9-59. What should youexternal partstand?

1. Soap and2. a soft li3. Windex4. Loxitt

use to clean thes of the 59A120 test

waternt-free cloth

9-60. How often are periodicinspections performed on theliquid oxygen converter teststand?

1. Every 20 hours2. Every 80 hours3. Weekly4. Monthly

9–61 . Which manual would you use tofind information on thereplacement of the system bleedvalve on the 59A120 test stand?

1. NAVAIR 13-1-6.42. NAVAIR 13-1-6.13. NAVAIR 15-17CB-024. NAVAIR 17-1513BC-20

9-55.

53

Assignment 10

Textbook Assignment: “Oxygen-Related Components.” Pages 12–1 through 12–33.

10-1.

10-2.

10-3.

10-4.

10-5.

Learning Objective: Identify,maintain, and perform mainte–nance on the CRU-79/P chest-mounted oxygen regulator.

The CRU-79/P regulator has asafety pressure of how manyinches of water above thesurrounding air pressure?

1. 0.5 to 2.02. 0.50 to 2.53. 0.5 to 5.24. 0.50 to 2.0

Inches of water is a means ofmeasuring the comparatively highpressure used in testing oxygenregulators.

1. True2. False

Safety pressure is maintained bythe CRU–79/p regulator up to andincluding what altitude?

1. 50,000 ft2. 43,000 ft3. 34,000 ft4. 25,000 ft

The CRU-79/P regulator has apressure-breathing feature thatwill maintain a pressure of upto 18.0 inches of water betweenwhat minimum altitudes?

1. 0 to 25,000 ft2 25,000 to 34,000 ft3. 34,000 to 50,000 ft4. 50,000 to 60,000 ft

DELETED

10-6.

10-7.

10-8.

10–9.

10-10.

What is the proper procedure tofollow if a CRU–79/P regulatorfails any inspection or testrequirement?

1. It is repaired at thesquadron level

2. It is repaired at the IMAlevel

3. It is repaired at depotlevel

4. It is disposed of inaccordance with localdirectives

A special inspection is per–formed on CRU-79/P regulators atintervals of how many days?

1. 102. 213. 304. 90

CRU79/P regulators are sub–jected to a calendar inspectionat intervals of at least howmany days?

1. 302. 903. 1204. 220

Which of the following teststands is used to test theCRU-79/P regulator?

1. 59A1202. 31TB1995–13. OTS 5834. 1172AS100

When you perform the overloadtest on a CRU-79/P regulator,how many inches of mercury iSmaintained on the mercurymanometer?

1. 1.02. 1.853. 1.304. 1.38

54

10-11. When you perform the safetypressure test on the CRU-79/Pregulator, the safety pressurereading will be indicated bywhich of the followingmeasurements?

1. Liter per minute2. Inches in water3. Pounds per square inch4. Inches of mercury

10-12. which of the following situa-tions would be the probablecause for a CRU-79/P regulatorto start pressure breathingbelow 35,000 feet?

1. A defective or damagedaneroid assembly

2. The aneroid assembly is toofar into the regulatorhousing

3. The aneroid assembly iS toofar out of the regulatorhousing

4. The aneroid sensingdiaphragm is installedbackwards

10-13. The outlet port of the miniatureregulator should never beblocked while pressure isapplied to the inlet.

1. True2. False

Learning Objective: Identify,maintaing and perform mainte-nance on aircraft panel-mountedoxygen regulators.

10-14. The panel-mounted regulatorsincorporate an emergencypressure control lever. Whichof the following is NOT asetting for this lever?

1. Emergency2. 100-percent3. Test mask4. Normal

10-15. The low-pressure, panel-mountedregulators have an operatingpressure range of how many psig?

1. 50 to 2002. 50 to 4003. 50 to 5004. 50 to 2,000

10-16. A panel-mounted regulator isconsidered beyond economicalrepair when the repair cost ismore than what percentage of thereplacement cost of theregulator?

1. 40%2. 50%3. 60%4. 75%

10-17. A discrepancyCRU-72/A regul

found on aator during a

transfer inspection should bereported to which of thefollowing work centers?

1. Material control2. Maintenance control3. Quality assurance4. Line division

10-18. Which of the following mainte-nance activities has the repaircapabilities for the panel-mounted regulator?

1. Organizational only2. Intermediate only3. Depot only4. Intermediate and depot

10-19. An acceptance inspection on aCRU-55/A regulator consists of avisual inspection followed bywhich of the following tests?

1. Outward leak test2. Inward leak test3. Functional test4. Safety pressure test

10-20. To receive oxygen at sea levelwith an MD-2 regulator, theemergency pressure control levermust be placed in what position?

1. Normal2. Test mask3. Emergency

10-21. When you perform a function teston an MD-2 regulator, which ofthe following indicators wouldshow that the regulator isoperating properly?

1. The low-pressure gauge2. The high-pressure gauge3. The emergency control lever4. The flow indicator

55

10-22.

10-23.

10-24.

10-25.

10-26.

Panel-mounted regulators are 10-27.inspected in accordance with theplanned maintenance system(PMS). This inspection CANNOTexceed what maximum number ofdays?

1. 912. 1803. 2204. 231

How often, if ever, should thesilicone rubber parts bereplaced on a MD-1 oxygenregulator?

1. Each time the regulator isdisassembled

2. Each time the regulator isinspected

3. Each time a function test isperformed

4. Never

Which of the following oxygensystems test stand is used tobench test a panel-mountedregulator?

1. 59A1202. 31TB1995-13. 117AS1004. OTS 565

Nitrogen supply cylinders usedin testing oxygen regulatorscontain a maximum pressure ofhow many psig?

1. 2,500 ±2002. 2,000 ±2003. 1,500 ±2004. 2,500 ±110

When you perform an inwardleakage test on a panel-mountedregulator. What is the maximumallowable leakage in cubiccentimeters per minute?

1. 1002002.

3. 3004. 400

10-28.

10-29.

10-30.

10-31.

To perform the outlet leakagetest on an MD-1 regulator, youmust apply a film of leakdetection compound over theregulator outlet. The filmshould not advance more thanwhat minimal distance, if any,to be allowable?

1. 1 inch in 15 seconds2. 3/4 inch in 20 seconds3. 1/2 inch in 10 seconds4. None

What is theif any, fortest?

1. 90 psig2. 60 psig3. 80 ccm4. None

What is theif any, fortest?

allowable leakage,the overall leakage

in 1 minutein 2 minutes

allowable leakage,the outward leakage

1. 0.12 ccm2. 120 lpm3. 0.12 lpm4. None

When you perform the secondStage relief valve test on apanel–mounted regulator, 3inches of mercury is applied tothe regulator outlet through thevent pressure valve on the teststand. The relief valve shouldvent at how many liters perminute?

1. 10252.

3. 304. 45

When you perform the flowsuction test on a panel–mountedregulator, the maximum flowthrough the regulator, with nosuction applied, is how manylpm?

1. 0.012. 0.023. 0.054. 0.10

56

10-32. What is the proper procedure tofollow if a panel-mountedregulator fails the oxygen ratiotest?

1. Dispose of it according tolocal directives

2. Perform an aneroid closuretest

3. Perform an emergencypressure test

4. Replace the venturi assembly

10-33. When you perform the aneroidclosure test, the aneroid shouldclose within what range?

1. 22,000 and 25,000 feet2. 25,000 and 28,000 feet3. 28,000 and 32,000 feet4. 32,000 and 43,000 feet

10–34. The blinker assembly testensures that the blinkeroperates correctly with a demandplaced on the regulator. When aflow of 12 lpm is drawn throughthe regulator, with 17.0 inchesof H2O indicated on thepressure/suction manometer, theblinker should be in whatposition?

1. Fully closed2. Half closed3. One quarter open4. Fully open

1. 502. 603. 754. 110

Learning Objective: Identify,maintain, and perform mainte-nance on liquid oxygenconverters.

10-35. Liquid oxygen (LOX) is stored atapproximately what temperature? 1. 110

2. 1153. 1254. 130

1. -282°F2. -297°F3. -282°C4. -297°F

10-36. The quantity gauge used on a LOXconverter indicates the amountof LOX in what units?

1. Pounds2. Gallons3. Liters4. Kilos

10-37. When you fill a LOX converterwith the use of a servicingtrailer, the converter isconsidered full when whatcondition exists?

1. The servicing trailerquantity gauge indicatesfull

2. The converter capacitanceprobe indicates full

3. The servicing trailer stopsdelivering LOX

4. A steady stream of LOX flowsfrom the overboard vent

10-38. At what approximate pressuredoes the LOX converter pressureclosing valve function?

1. 60 psig2. 75 psig3. 100 psig4. 110 psig

10-39. A relief valve is incorporatedinto LOX systems to preventexcessive pressure buildup. Onmost LOX systems this reliefvalve is set to open atapproximately how many psig?

10-40. Additional protection againstover pressurization of a LOXconverter installed in anaircraft is a relief valveinstalled in the aircraft oxygenplumbing. This relief valve isset at approximately how manypsig?

10-41. When performing the relief valvetest, a pressure of 100 to 120psig is applied to the reliefvalve. The relief valve shouldvent a minimum of how manyliters per minute?

1. 502. 1003. 1504. 200

57

10-42.

10-43.

10-44.

10-45.

10-46.

The converter leakage test isperformed with the converterpressurized to how many psig?

1. 552. 653. 954. 110

The time required to fill a10-liter LOX converter at afilling pressure of 30 psigshould NOT exceed what maximumnumber of minutes?

1. 52. 103. 154. 30

A LOX converter should maintaina pressure of 55 to 90 psigwhile delivering a flow of howmany liters per minute?

1. 502. 1003. 1204. 200

To prevent moisture fromentering the converter duringshipment or storage, theconverter should be pressurizedwith gaseous oxygen to a maximumpressure of how many psig?

1. 10 to 152. 15 to 253. 25 to 304. 30 to 40

Liquid oxygen converters aresubject to a calendar inspectiona minimum of every 231 days.This interval applies to whichof the following typeconverters?

1. Aircraft–installed2. Shop spares3. Servicing pool4. All of the above

10-47.

10-48.

When performing a bench test ona liquid oxygen converter, thefirst step is to find theconverter’s tare weight. TOensure this is done properly,you must use a scale that has acapacity of at least how manypounds?

1. 502. 203. 304. 40

When you measure the outlettemperature of the purging unit,the temperature should bebetween how many degreesFahrenheit?

1. 100 and 1252. 125 and 1503. 150 and 2004. 200 and 250

10-49. What is the purging time for a10-liter LOX converter?

1. 30 to 40 minutes2. 45 to 75 minutes3. 75 to 83 minutes4. 85 to 90 minutes

10-50. When you purge a LOX converter,what should be the maximum inletpressure and temperature?

1. 60 psig and 250°F2. 55 psig and 200°F3. 55 psig and 250°F4. 65 psig and 200°F

10-51. When you perform an insulationresistance test on an emptyconverter , the megohmmeter rangeselector on the test stand isset on what position?

1. Zero2. X-13. X-104. X-100

10–52. When you perform the capacitancetest on an empty converter, thereading on the test stand shouldbe between how many micro–microfarads/

1. 90.3 to 111.5 (UUF)2. 110.5 to 121.5 (UUF)3. 150.0 to 250.0 (UUF)4. 121.5 to 125.5 (UUF)

58

10-53. When you perform the reliefvalve test on a LOX converter,the relief valve relieves aminimum of how many liters perminute with a pressure of 120psig applied to the converter?

1. 502. 703. 1004. 110

10-54. When you perform the fill andbuildup time test on aconverter, the filling pressureis maintained at how many psig?

1. 302. 503. 604. 70

l0-55. What is the maximum time itshould take to fill a LOXconverter, if the proper fillingpressure is maintained?

1. 10 minutes2. 15 minutes3. 20 minutes4. 25 minutes

1. 5 lb2. 2 lb3. 3 lb4. 4 lb

10-56. After you have completed thefill test, you should perform apressure buildup test. What isthe required time to buildup aworking pressure of 70 to 80psig?

1. 1 minute2. 5 minutes3. 10 minutes4. 15 minutes

10-57. When you perform the capacitancetest on a full LOX converter,the capacitance range selectorknob is set at which of thefollowing positions?

1. Full2. 1x3. 10X4. 100X

10-58. After a period of 24 hours, theevaporation loss should NOTexceed how many pounds of liquidoxygen when the converter is inthe buildup and supply mode?

1. 1 lb2. 2 lb3. 3 lb4. 4 lb

10-59. When performing the evaporationloss test with the converter inthe vented mode, the loss shouldnot exceed how many pounds in 24hours?

10-60. When performing the flow test ona liquid oxygen converter, youshould apply a flow of 120 lpm.With this flow maintained, theconverter should maintainpressures of how many psig?

1. 40 to 552. 55 to 903. 90 to 1104. 110 to 115

59