USAARL REPORT NO. 84-6

IN-FLIGHT EVALUATION OF TWO MOLECULAR SIEVEOXYGEN CONCENTRATION SYSTEMS IN U.S. ARMY

AICRF (JUN-IN AND JU-2 161

ByWilliam A. Chaffin, Jr.

Bruce F. HlottFrancis S. Knox III

BIOMEDICAL APPLICATIONS RESEARCH DIVISION

~~rm) ~~March 1084 ~ MY118

VlI 1I 1II

U.S. ARMY AEROMEDICAL RESEARCH LABORATORYFORT RUCKER, ALABAMA 36362

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USAARL Report No. 84-6 ________(_ _ ______._._._

4. TITLE (•nd Subliele) S. TYPE OP REPORT & PERIOO COVEREDIn-Flight Evaluation of Two Molecular Sieve

Oxygen Concentration Systems in U.S. Army Aircraft Final ReportJUH-H and JU-21G) . PERFORMING ORG. REPORT NUMBER

7. AUTHO4R() S. CONTRACT OR GRANT NUMBER(*)

William Chaffin, Jr.Bruce F. HiottFrancis S. Knox III9. PERFORMING OROANIZATION N NAIR AND ADDRESS 10. PRORAM ELEMEN T, PROJECT, TASK

SGRD-UAB*CB NUMBERUS Amy Aeromedical Research LaboratoryFort Rucker, Alabama 36362 .. 6777A E162777ARZ AF 114I0. CONTROLLINO OPICE NEAMr AND ADDRESS 12, REPORT OATE

US Amy Medical Research and Development Command March 1984Furt Derlck ,. NUMBER OF PAGES"Frederick, Maryland 21701 . 3814. MO'IITORINO AGENCY NAME & AOORESS(It dilfleraf how Controllind Office) 1S. SECURITY CL %SS. (4-l Oda report)

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Approved fer public release; distribution unlimited.

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II. SUPPLEMENTARY NOTES -- - •

% PTISc .El1),f IC UB 5l

3 4T.lt$4 oat t OL----

It. KEY WORDS (Continue on reverse old* it necessay and Identlify by' block numiber) .

• olecular sieve Oxygen Concentrators ____r___

eolite Pressure Differential Distvibt.Os/Pressure Swing • - - etbl,..o0-

25I ArACT (vCra -immmve HobH now.ea d idelty by block nombee) 1,-) z t spIvlar

See back of form. .

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20. ABSTRACT:

-- The logistical problems associated with using high pressure gaseous oxygensystems have encouraged the development of molecular sieve oxygen concentrationsystems for use on board aircraft. This report summarizes the in-flight staticperformance characteristics of two such oxygen concentrators installed in aJU-21G fixed-wing, twin-engine turbopropeller aircraft and a JUH-lH turbine-powered helicopter. Flight profiles consisting of five separate flights ataltitudes of 1,524, 3,048, 4,572, 6,096, and 7,620 meters (5,000, 10,000, 15,000,20,000, and 25,000 feet) were flown in the JU-21G and five separate flights at

" * altitudes of 1,524, 3,048 and 4,572 meters were flown in the JUH-1H. Oxygenconcentration at flows of 15, 25, 35, and 70 liters per minute were recorded ateach altitude. These flows were chosen to represent normal breathing require-ments for one- and two-man crews. In all cases, the concentrators met or ex-ceeded the requirements of MIL-R-83178. The use of engine bleed air to drivethe oxygen concentrators produced no noticeable effect on aircraft performance,

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UNCLASSI FIED*SCCUMITY CLASSIFICATION OF THIS PAOE(Whn Daes FPneevd)

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Lt.,.. . ., :•- ,'2 •:•,._.,-.-._.: ._ 5•".. . .,. .." .". ;"".. ... ' ,_ : .,' ' - t • • -''--" " ' _. .-.

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Disclaimer

The views, opinions, and/or findings contained in this report are those ofthe author(s) and should not be construed as an official Department of theArmy position, policy, or decision, unless so designated by other officialdocumentation. Citation of trade names in this report does not constitutean official Department of the Army endorsement or approval of the use of suchcommercial items.

Reviewed:

Direc orBiomedical Applications Research

Division Released for Publication:

J. . LaMOTHE,eh.D. DUDLEY RICELTC, MS Colonel, C, SFSChairman, Scientific Review Commanding

Commi ttee

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ACKNOWLEDGEMENT

The authors take this opportunity to acknowledge with thanks the manyvaluable contributions by LTC Philip Taylor and SFC Richard Weber during thedata collection, data analysis, and writing/editorial phases of this project.

TABLE OF CONTENTS

PAGE NO.

List of Illustrations .......... ....................... 2

List of Tables ............ .......................... 3

Introduction ............... .......................... 4

Apparatus ............. ............................. 6

Procedure ............. ............................. 11

Results .............. .............................. 11

Discussion .............. ............................ 26

Conclusions ........ ............................ .. 27

References Cited ............ ......................... 30

Appendix A - Equipment and Manufacturer List ..... ........... 31

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LIST OF ILLUSTRATIONS

FIGUR PAGE NO.

1. M1olecular Sieve Block Diagram................ 5

2. JU-21G Research Aircraft .......... ................. 7

3. JU4H- 1 >-search Aircraft ........ ................... 8

4. Oxygen Concentrators ........ ...................... 9

5. re-. Stand ........ ........................ .l.O... 10

• 6. Oxygen Concentration vs. Altitude in JU-21G(Bendix Unit, Minimum Power) ...................... 12

m %7. Oxygen Concentration vs. AIltitude in JU-21G(Bendix Unit, :laximum Power) ...................... 13

8. Oxygen Concentration vs. Altitude in JU-21G(Garrett Unit, Miinimum Power) .................. ..... 14

9. Oxygen Concentration vs. Altitude in JU-21G(Garrett Unit, Maximum Power) .................. ..... 15

10. Oxygen Concentration vs. Altitude in JUH-lH(Bendix Unit) ......... ....... ..... ....... ..... 16

11. Oxygen Concentration vs. Altitude in JUH-lH(Garrett Unit) .. ...... ....... ..... ......... .... 17

12. Oxygen Concentration vs. Altitude in J'1-21G(Garrett Unit, Hinimum Power). Supplemental Data. . . . 23

13. Oxygen Concentration vs. A\ltitude in J'J-21G(Garrett Unit, Maximum Power). Supplemental Data. . . . 29

672

"ii'•

ILIST OF TABLES

TABLE PAGF NO.

1. Oxygen Concentration and System Condition UnderStatic Flow (Bendix/JU-21G) ................... ..... 18

2. Oxygen Concentration and System Condition UnderStatic Flow (Garrett/JU-21G) .... .............. .... 20

3. Oxygen Concentration and System Condition UnderStatic Flow (Bendix/JUH-1H) ................... ..... 22

4. Oxygen Concentration and System Condition UnderStatic Flow (Garrett/JUH-lH) ...... ... .............. 23

5. Oxygen Concentration and System Condition UnderStatic Flow (Garrett/JU-21G). Supplemental Data . . .. 24

ed

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,*II

INTRODUCTION

In 1947, with the formation of the US Air Force as a separate branch ofservice, US Army aviation relinquished most of its high-altituwle capabil-

4 ities, requirements, and aircraft, resulting in a role of reduced importancefor oxygen delivery systems in the Army aviation environment. Today, however,there are increased mission requirements, both training and operational, whichdictate routine flights in certain aircraft to altitudes as high as 7,620meters (25,000 feet) in an unpressurized cabin. As a result, oxygen systemsare again a critical part of US Army aircraft life support systems. Cur-

4,• rently, US Army aviation oxygen needs are satisfied only partially bycontinuous flow and diluter demand gaseous oxygen systems due to space,

P weight, and logistical limits. Additionally, the effectiveness of thesesystems is compromised by several factors. The amount of oxygen availableduring a given flight is limited by the number of high-pressure cylinderscarried on board the aircraft. Carrying extra cylinders results in a weightand space penalty which reduces operational aircraft cipability. Gaseoussystems require frequent refilling which prolongs aircraft turnaround time.

-There also are high risk safety hazards associated with the storage, servicing,and use of high pressure gaseous oxygen systems; and logistical servicingfacilities are not normally available at remote locations.

The logistical problems associated with using high pressure gaseous oxygensystems have encouraged the development of molecular sieve oxygen concentra-tion systems for use on board aircraft. The US Army, Navy, and Air Forceare studying the applicability of these systems for use on high performance

4 jet aircraft, turbopropeller aircraft, and turbine-powered helicopters(Ernsting et al., 1980; Knox et al., 1981; Miller et al., 1980; and PettyjohnI et al., 1977).

A typical concentrator contains two can'iisters or "beds" filled with a

synthetic zeolite molecular sieve material of five Angstrom pore size.These two beds are pressurized alternately with bleed air diverted from thecompressor stage of the turbine engine. During pressurization, oxygen in thebleed air is separated from nitrogen and then vented through the output port.Nitrogen is trapped in the zeolite molecular sieve material. The bed then isdepressurized to the atmosphere as a nitrogen exhaust purge which completesthe unit's "pressure swing cycle." During this phase of the cycle, some ofthe concentrated oxygen from the pressurized bed is bled in the reverse di-rection through the depressurized bed to assist in the nitrogen purge. Thus,when one bed is ccncentrating oxygen, the other is being purged of nitrogen.A rotary valve directs the flow of bleed air and also controls the flow ofoxygen-enriched air and nitrogen purge. The valve is actuated by a 28-volt DCmotor that is powered by the aircraft electrical system. A block diagram ofthis process is shown as Figure 1. This report summarizes the in-fliCht static

performance characteristics of two such oxygen concentrators installed in a

4

1'• MOLECULAR SIEVE BED

,•e• ALUEEL

:

ENGINE BLEED NITROEN I ROIFIOE ENRICHEDAll IiLET POROE'EXIAUST )0\UEIFICE OUTPUT

i REGULATOR

f•.i MOLECULAR SIEVE BED

MOLECULAR SIEVE BLOCK DIAGRAM

FIGURE 1. Molecular Sieve Block Diagram

5

JU-21G fixed-wing, twin-engine, turbopropeller aircraft (Figure 2) and a JUH-lH

turbine-powered helicopter (Figure 3). Such an effort is a necessary firststep for evaluation of candidate systems within the range of physiological re-quirements.

METHOD

APPARATUS

Two oxygen concentrators were tested, one manufactured by the Garrett% Corporation* and the other by the Bendix Corporation* (Figure 4). Each unit

occupies approximately one cubic foot and operates by basically the samemethod.

In the JU-21G, instrumentation for n-flight testing and data collectionwas installed in a specially-built test stand (Figure 5). Bleed air from theright engine at 15 to 55 pounds per square inch gauge (psig) was fed intothe test stand through a 15.78mm (5/8-inch) internal diameter (ID) oxygen line.A 4.5-liter plenum chamber was installed to facilitate instrumentation anddampen pressure fluctuations caused by the pressure swing of the molecularsieve concentrator. Inlet bleed air pressure was measured by a Validynedifferential pressure transducer* and a Harris sight gauge.* Temperature wasmeasured with a Cole-Palmer digital thermometer* before the air was directedfrom the plenum chamber through the oxygen concentrator. The oxygen-enrichedair (product gas) exited the concentrator and passed into a second 4.5-literplenum chamber where the outlet pressure and temperature again were monitoredand recorded using another Validyne differential pressure transducer, Harrissight gauge, and Cole-Palmer digital thermometer. Upon exiting the outletplenum, the product gas was fed through a 9.5mm (3/8-inch) ID oxygen line toa Technology, Incorporated mass flow meter.* A shutoff valve, in conjunctionwith a Fischer-Porter rotameter*, was used to set various flows. Oxygen con-centration was measured using a fast response Beckman OM-14 oxygen analyzer*equipped with an altitude sensor. A Wallace and Tiernan barometer* was usedto measure ambient barometric pressures. Standard aircraft instrumentation wasused for torque, engine temperature, airspeed, and altitude measurements.Calibration of instrumentation was maintained on a flight-by-flight basis atboth ground level and at the various sampling altitudes.

The same instrumentation package was used for testing in the JUH-lH withthe only difference being a slight modification of the test stand to allow forproper securing of the stand to the helicopter's cargo attachment points.

*Indicates product manufacturer listed in Appendix A.

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FIGURE 2. JU-21G Research Aircraft.

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PROCEDURE

In the JU-21G, five separate flights at altitudes of 1,524, 3,048, 4,572,6,096, and 7,620 meters (5,000, 10,000 15,000, 20,000, and 25,000 feet) wereconducted with each oxygen concentration unit. Four different flows of 15,25, 35, and 70 liters per minute were chosen to represent normal breathingrequirements for one- and two-man crews. Data were recorded for each flow atall altitudes and at both minimum and maximum engine power settings. Minimum

... power was defined as the power required to fly at 130 knots indicated airspeed(IAS) while maximum power was defined as 208 knots IAS with Interstage TurbineTemperature -(ITT) not to exceed 7050 C. At these power settings, the inletbleed air pressures at the oxygen concentrator were consistently in the rangeof 28 to 55 psig and oxygen-enriched air outlet pressure ranged from 22 to 28psig, which is well within the limits of the low pressure oxygen regulatorsdesigned for use with molecular sieve oxygen concentration units. In theJUH-lH, five separate flights at altitudes of 1,524, 3,048, and 4,572 meters(5,000, 10,000, and 15,000 feet) were conducted with each oxygen concentrationunit. Flow rates were the same as in the JU-21G, and the engine power settingwas constant over the entire flight test period.

RESULTS

Oxygen concentrations and other system considerations for the JU-21Gflights are shown for the Bendix unit in Table I and for the Garrett unit inTable 2. Oxygen concentration and system data for the JUH-lH flights areshown in Table 3 for the Bendix unit and in Table 4 for the Garrett unit.Generally, with both units, oxygen concentration decreased with increasedflow and increased with higher altitude. In the JU-21G, oxygen concentrationgenerally decreased with the higher engine power setting. However, with theBendix unit, this condition was reversed in some instances. In all cases, asshown in Figures 6 through 11, oxygen concentration met or exceeded the re-quirements (indicated by the stippled area) of MIIL-R-83178.

Data first recorded upon reaching a new altitude (low flows, Figures 6-9)often showed overlap where it was supposed there should be none. A carefulreview of data collection procedures revealed that it usually took 4 to 6minutes for the system to stabilize and be repeatable. In order to test theworking hypothesis that the initial readings in Figures 6 through 9 were takenprior to system equilibrium, data were recorded during three additional flightsin the JU-21G at each altitude, allowing more time between flow changes andaltitude changes for the system to stabilize. The data for the Garrett unitIs presented in Table 5 and Figures 12 and 13 for these additional flights.Two low-altitude flights were made with the Bendix unit when the aircraft

11

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ALTITUOD (Thousands)

FIGURE 6. Oxygen concentration vs. altit,,de in JU-21G(Bendix unit, minimum power). Stippled area indicatesoxygen requirements of )((L-R-83178. Bars indicatestandard deviation at each data point.

12

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Mete0 s 2 4 6 8 10

Foe t 1 o 1 '5 2,0 25 30 35

ALTITUDE IThousands)

FIGURE 7. Oxygen concentration vs. altitude in .J-2 .I

(Bendix unit, maximum power). Stippled area indicatesoxygen requirements of 'IIL-R-93178. Bars indicatestandard deviation at each data poinL.

13

2S 1PM

35 1PM

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ALTITUDE (Theousnds)

FIGURE B. Oxygen concentration vs. altitude in JU-21G(Garrett unit, minimum power). Stippled area indicatesoxygen requirements of tlIL-R-83178. Bars indicatestandard deviation at each data point.

14

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ALTITUDE (Theuunsahs

FIGURE 9. Oxygen concentration vs. altitude in JU-21G(Garrett unit, maximum power). Stippled area indicatesoxygen requirements of 'IIL-R-83178. Bars indicatestandard deviation at each data point.

15

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ALTITUDE (Thousands)

FIGURE 10. Oxygen concentration vs. altitude in JUH-1lH (Bendix unit).Stippled area indicates oxygen requirements of 1IIL-R-83178. Barsindicate standard deviation at each data point.

16

100

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ALTITUDE (Thousandsl

FIGURE 11. Oxygen concentration vs. altitude in JUH-1H (Garrett unit).Stippled area indicates oxygen requirements of !IIL-R-83178. Barsindicate standard deviation at each data point.

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suffered a lightning strike. The aircraft main electrical inverters malfunc-tioned and the motor in the Bendix On-Board Oxygen Generating System (OBOGS)unit would not operate in the laboratory after the flight. The unit is beingrepaired. No additional data for the Bendix unit is reported.

Other aircraft flight parameters which were recorded, but not included inthis report were engine torque and ITT or exhaust gas temperature. There wasno noticeable difference in the instrumentation readings nor could the pilots"feel" when the concentrators were being driven by bleed air.

DISCUSSION

4raStatic testing of the molecular sieve concept of onboard oxygen concen-tration systems for the Army aircraft is a necessary first step to insure theirphysiological adequacy. Although each unit met or exceeded the requirementsof MIL-R-83178, the results obtained in the JUH-lH helicopter differed fromthose obtained in the JU-21G fixed-wing aircraft. A comparison of theseresults shows that the Garrett unit performed similarly in both aircraft whenthe JU-21G was at maximum power. The Bendix unit, however, in some instances,produced a lower oxygen concentration in the JUH-lH than in the JU-21G. Acomparison of these data with the data in Table I of Ernsting et al. (1980)reveals that operation of these units in flight produces oxygen concentrationsslightly hiqher with the Garrett unit and slightly lower with the Bendix unitthan the respective values obtained during tests in the hypobaric chamber.

The oxygen concentration process of the molecular sieve depends on manyfactors including flow, inlet temperature, inlet pressure, and the pressuredifferential across the molecular sieve bed. Additionally, although the causehas not been definitely determined, the resistance of the nitrogen exhaustpurge hose seems to be a factor and attention should be directed to the designof an exhaust port to maximize oxygen concentration. The differences inoxygen concentration reported here and those reported by Ernsting are probablya result of differences in all of these factors. One notable difference intest procedures was our use of heated engine bleed air instead of unheatedlaboratory instrument air as used in Ernsting's hypobaric chamber tests. Bothunits have internal pressure regulators which limit the inlet pressure tobetween 25 and 28 psig. This effectively eliminates the effect of bleed airpressure changes that might result from differing engine power settings sinceeven minimum engine power settings produce bleed air pressurp in excess of 25psig.

The use of engine bleed air to drive the oxygen concentrators produced nonoticeable effect on aircraft performance.

During the upcoming toxicology phase of this project, in which testswill be conducted to determine whether or not any harmful substances from

26

bleed air exhaust are passed through the molecular sieve, the noted varia-bles will be studied more closely and an attempt will be made to optimizethem for maximum oxygen production.

The results in Table 5 and Figures 12 and 13 confirm the hypothesis thatsome early readings were taken prior to system equilibrium. This means thatthe first set of data is slightly more conservative in stating oxygen outputat low flows and at the lower altitudes.

The primary objective of the study was to assess the physiological ade--quacy-of these molecular sieve oxygen concentration units in order to qualify

hem for human use so that dynamic-human interface can be studied in flight.- The results obtained indicate that both units generate enough oxygen to sup-

port two human subjects in a dynamic breathing study. There is a possibilitythat two aviators under high workload conditions (e.g. Night NOE with NVG)would require minute volumes greater than these systems can produce.

CONCLUSIONS

Oxygen production by each of the molecular sieve oxygen concentratorsstudied met or exceeded the requ-rements of t1IL-R-83178 at all flows andaltitudes. Both units have showo themselves capable of producing the oxygenrequired at normal minute volumes for a one- or two-man crew on the JUH-1H andJU-21G aircraft. However, in cases .4here no air mix is allowed and the aviatorsare under high stress, it would be possible for two aviators to attempt to overbreathe the system. Prior to initial human interface studies, however, it willbe necessary to complete product gas toxicology tests to insure that contami-nants from aircraft engine bleed Jir are not passed through the concentratorsin harmful amounts.

27

"MU

2df 4 6 1 10

Feet I' A0 h5 A0 h5 A

ALTITUDE IThsusandsl

FIGURE 12. Garrett Minimum Power - JIJ-21G. (Supplemental Data)

1 28

101 - -

SISLPU

S

7OL

2 MILl 13113

r � 2 4 6 S 10

ALTITUOf (Thousandsl

FIGURE 13. Garrett "laximum Power - JU-21G. (Supplemental Data)

29

PI

REFERENCES CITED

Ernsting, J., Armstrong, R. N., Hlott, B. F., and Holden, R. D. 1980.A phyeiologioal evaluation of two types of molecular sieve generationesyetem. Preprints of the scientific program, Aerospace MedicalAssociation, 1980 Annual Scientific Meeting; Anaheim, CA. pp. 131-132.

Knox, F. S., Hiott, B. F., Alexander, J., Jr., and Biggs, F. 1981. Evalua-tion of onboard oxygen eyeteme for U.S. Army aircraft. Preprints of theScientific Program, Aerospace Medical Association, 1981 Annual Scientific

Meeting; San Antonio, TX. pp. 195-196.

Miller, R. L., Ikels, K. G., Lamb, M. J., Brooks, E. J., and Ferguson, R. H.1980. Molecular sieve generation of aviator'a oxygen: Performance ofa prototype under simulated flight conditions. Aviation, Space andEnvironmental Medicine 51(7) :665-673

Pettyjohn, F. S., McNeil, R. J., Akers, L. A., Rice, G. P., and Piper, C. F.1977. Aeromedioal evaluation of the Army molecular ?ieve oxygen genera-tion (6.$SOG) systems. Fort Rucker, AL: U.S. Army Aeromedical ResearchLaboratory. USAARL Report 77-10.

Department of Defense. 1974. General Specificatione for Regulator, Oxygen,Diluter Demand, and Automatic Pressure Breathing. Washington, DC,: Dept.of Defense. MIL-R-83178.

.30

I

APPENDIX A

EQUIPMENT AND MANUFACTURER LIST

31

EQUIPMENT AND MANUFACTURER LIST

Molecular Sieve Oxygen Generator4odel 2202490-1 -1Serial #49-RlAiResearch Mfg Co. of CaliforniaGarrett Corporation'K . Validyne Differential Pressure

- .Transducer1914 Londelius StreetNorthridge, California 91324

Technology Incorporated, MassFlow Meter

Dayton, Ohio 45431

Harris Pressure GaugeMlelbourne, Florida 32901

Wallace and Tiernan BarometerBelleville, New Jersey 07109

Molecular Sieve Oxygen ConcentratorModel 99251-3261009-0105Serial #90801 5E

*Bendix Instruments and Life SupportDivision

Davenport, Iowa 52802

Beckman OM-14 Oxygen Analyzer2500 Harbor BoulevardFullerton, California 92634

Cole-Palmer Digital ThermometerChicago, Illinois 60648

Fischer-Porter RotameterWarminister, Pennsylvania 18974

*Now known as Clifton Precision

32

*1'a

INITIAL DISTRIBUTION

Commander Naval Air Development CenterUS Army Natick R & D Laboratories Tech Info DivATTN: Tech Librarian Technical Support DepartmentNatick, MA 01760 Warminster, PA 18974

Commander CommanderUS Army Research Institute of Naval Air Development Center

Environmental Medicine ATTN: Code 6022 (Mr. Brindle)-Natick, MA 01760 Warminster, PA 18974

US Navy Dr. E. HendlerNaval Sub Med Rsch Lab Code 6003Med Library, Naval Submarine Base Naval Air Development CenterBox 900 Warminster, PA 18974Groton, CT 06340

DirectorUS Army Avionics R & D Activity Army Audiology & Speech CenterATTN: DAVAA-0 Walter Reed Army Medical CenterFort Monmouth, NJ 07703 Forest Glen Section, Bldg 156

Washington, DC 20012Cdr/DirUS Army Combat Surveillance & Director

Target Acquisition Lab Walter Reed Army InstituteATTN: DELCS-D of ResearchFort Monmouth, NJ 07703 Washington, DC 20012

US Army R & D Technical CommanderSupport Activity US Army Institute of

Fort Monmouth, NJ 07703 Dental ResearchWalter Reed Army Medical Center

Commander Washington, DA 2001210th Medical LaboratoryATTN: DEHE (Audiologist) Uniformed Services UniversityAPO New York 09180 of the Health Sciences

4301 Jones Bridge RoadChief Bethesda, MD 20014Benet Weapons LaboratoryLCWSL, USA ARRADCOM Commanding OfficerATTN: DRDAR-LCB-TL Naval Medical R & D CommandWatervliet Arsenal National Naval Medical CenterWatervliet, NY 12189 Bethesda, MD 20014

Commander Under Secretary of Defense forNaval Air Development Center Research and EngineeringBiophysics Lab (ATTN: George Kydd) ATTN: Mil Asst for MedicalCode 60BI and Life SciencesWarminster, PA 18974 Washington, DC 20301

Human Factors Engr Div Director of Professional ServicesAcft & Crew Systems Tech Dir Office of The Surgeon GeneralNaval Air Development Center Department of the Air ForceWarminster, PA 18974 Washington, DC 20314

33

Naval Air Systems Command CommanderTech Library Air 950D US Army Med Rsch InstituteRm 278, Jefferson Plaza II of Chemical DefenseDepartment of the Navy Aberdeen Proving Ground, MDWashington, DC 20361 21010

US Navy Technical LibraryNaval Research Lab Library Chemical Systems LaboratoryCode 1433 Aberdeen Proving Ground, MD 21010Washington, DC 20375

CommanderUS Navy US Army Medical R & D CommandNaval-Research Lab Library ATTN: SGRD-RMS (Mrs. Madigan)Shock & Vibration Info Ctr Fort jetrickCode 8404 Frederick, MD 21701Washington, DC 20375

CommanderHarry Diamond Laboratories US Army Med Rsch InstituteScientific & Technical of Infectious Diseases

Information Offices Fort Detrick2800 Powder Mill Road Frederick, MD 21701Adelphi, MD 20783

CommanderDirector US Army Med BioengineeringUS Army Human Engineering R & D Laboratory

Laboratory Fort DetrickATTN: Tech Library Frederick, MD 21701Aberdeen Proving Ground, MD

21005 Dir of Biol & Med Sciences Div

Office of Naval ResearchUS Army Material Systems 800 N. Quincy Street

Analysis Agency Arlington, VA 22217ATTN: Reports DistAberdeen Proving Ground, MD Defense Technical

21005 Information Center

Cameron Station, VA 22314US Army Ordnance Center

and School US Army Materiel Development &Library, Bldg 3071 Readiness CommandATTN: ATSL-DOSL ATTN: DRCSGAberdeen Proving Ground, MD 5001 Eisenhower Avenue

21005 Alexandria, VA 22333

DirectorBallistics Research Lab US Army Foreign Science &ATTN: DRDAR-TSB-C (STINFO) Technology CenterAberdeen Proving Ground, MD ATThn: DRXST-IS

2100s 220 7th Street, NECharlottesville, VA 22901

US Army Environmental Hygiene

Agency Library, Bldg E2100Aberdeen Proving Ground, MD

21010

34

Coommande r Commander

US Army Transportation School US Army Aeromedical Center

ATTN: ATSP-TD-ST rt Rucker, AL 36362

Fort Eustis, VA 23604Commander

Commander US Army Avn Center &

US Army Airmobility Laboratory Fort Rucker

ATT: Library ATTN: ATZQ-CDR

Fort Eustis, VA 23604 Ft Rucker, AL 36362

US Army Training and Director

Doctrine Command Directorate of Combat

ATTN: ATCD Developments

Fort Monroe, VA 23651 Bldg 507Ft Rucaer, AL 36362

CommanderUS Army Training and Director

Doctrine Command Directorate of Training

ATTN: Surgeon Development

Fort Monroe, VA 23651 Bldg 502Ft Rucker, AL 36362

US Army Research andTechnology Laboratory Chief

Structures Laboratory Library Army Research Institute

NASA Langley Research Center Field Unit

Mail Stop 266 Ft Rucker, AL 36362

Hampton, VA 23665Commander

US Navy US Army Safety Center

Naval Aerospace Medical Ft Rucker, AL 36362

Institute LibraryBldg 1953, Code 102 CommanderPensacola, FL 32508 US Army Aviation Center

& Fort Rucker

US Air Force ATTN: ATZQ-T-ATL

Armament Development and Ft Rucker, AL 36362

Test CenterEglin Air Force Base, FL 32542 Commander

US Army Aircraft

Colonel Stanley C. Knapp Development Test Activity

US Central Command ATTN: STEBG-MP-QA

CCSG MacDill AFB, FL 33608 Cairns AAFFt Rucker, AL 36362

Redstone Scientific InformationCenter President

DRDMI-TBD US Army Aviation Board

US Army Missile R & D Command Cairns AAF

Redstone Arsenal, AL 35809 Ft Rucker, AL 36362

Air University Library Canadian Army Liaison Officer

(AUL/LSE) Bldg 602

Maxwell AFB, AL 36112 Ft Rucker, AL 36362

35

INetherlands Army Liaison Office CommanderBldg 602 US Army Aviation Systems Command (Prov)

* Ft Rucker, AL 36362 ATTN: SGRD-UAX-AL (Maj Lacy)Bldg 105

German Army Liaison Office 4300 Goodfellow BoulevardBldg 602 St Louis, MO 63166Ft Rucker, AL 36362

CommanderBritish Army Liaison Office US Army Aviation Systems Command (Prov)Bldg 602 ATTN: DRDAV-E-tRucker,_AL 36362 4300 Goodfellow Blvd

St Louis, MO 63166French Army Liaison Office .. .Bldg 602 ComanderFt Rucker, AL 36362 US Army Aviation Systems Command (Prov)

ATTN: LibraryUS Army Research and 4300 Goodfellow Blvd

Technology Labs St Louis, MO 63166Propulsion Laboratory MS 77-5NASA Lewis Research Center Commanding OfficerCleveland, OH 44135 Naval Biodynamics Laboratory

PO Box 24907Human Engineering Division Michoud StationAir Force Aerospace Medical New Orleans, LA 70129

Research LaboratoryATTN: Technical Librarian Federal Aviation AdministrationWright Patterson AFB, OH Civil Aeromedical Institute

45433 ATTN: LibraryBox 25082

US Air Force Institute of Oklahoma City, OK 73125Technology (AFIT/LDE)

Bldg 640, Area B US Army Field Artillery SchoolWright-Patterson AFB, OH 45433 ATTN: Library

Snow Hall, Room 14John A. Dellinger, MS, ATP Fort Sill, OK 73503Univ of Ill - Willard AirportSavoy, IL 61874 Commander

US Army Academy of Health SciencesHenry L. Taylor ATTN: LibraryDirector Ft Sam Houston. TX 78234Institute of AviationUniv of Ill - Willard Airport CommanderSavoy, IL 61874 US Army Health Services Command

ATTN: Library4 Commander Ft Sam Houston, TX 78234

US Army Troop Support andAviation Material Readiness Cmd Commander

ATTN: DRSTS-W US Army Institute ofSt Louis, MO 63102 Surgical Research

Ft Sam Houston, TX 78234

36

-*i1 _•i. . al • ... 1 r: r: . i- • . a. c.c r c .-r • lt i f .- ' a .v .. wr.• . . _- 4 • • 1..- .- . I o

US Air Force CommanderAerospace Medical Division Letterman Army Institute of RschSchool of Aerospace Medicine ATTN: Med Rsch LibraryAeromedical Library/TSK-4 Presidio of San FranciscoBrooks AFB, TX 78235 CA 94129

US Army Sixth US ArmyDugway Proving Ground ATTN: SMATechnical Library Presidio of San FranciscoBldg 5330 CA 94129

. . Dugway, UT 84022 Director

Dr. Diane Damos -Naval Biosciences LaboratoryPsychology Department Naval Supply Center, Bldg 844Arizona State University Oakland, CA 94625Tempe, AZ 85287

US Army Yuma Proving GroundTechnical LibraryYuma, AZ 85364

US Army White Sands Missile Range

Technical Library Division

White Sands Missile RangeNew Mexico, 88002

US Air ForceFlight Test CenterTechnical Library, Stop 238Edwards AFB, CA 93523

US Army Aviation EngineeringFlight Activity

ATTN: DAVTE-M (Tech Lib)Edwards AFB, CA 93523

US NavyNaval Weapons CenterTech Library DivisionCode 2333China Lake, CA 93555

US Army Combat DevelopmentsExperimental Command

Technical LibraryHq, USACDECBox 22Ft Ord, CA 93941

Aeromechanics LaboratoryUS Army Rsch & Tech LabsAmes Research Center, M/S 215-1Moffett Field, CA 94035

37

504

Col G. Stebbing National Defenc HeadquartersDAO-AMLOUS B 101 Colonel By 'riveBox 36, US Embassy Ottowa, Ontario CanadaFPO New York 09510 KIA OK2

ATTN: DPMStaff Officez, Aerospace MedicineRAF StaffBritish Embassy3100 Massachusetts Ave, NWWashington. DA 20008

D-p'rrtment of DefenceR.A.N. Rsch LaboratoryP.O. Box 706Darlinghurst, N.S.W. 2010Australia

Canadian Society of Avn Medc/o Acad of Med, TorontoATTN: Ms Carmen King288 Bloor Street WestToronto, OntarioM55 IV8

Canadian Air Line Pilot's AssnMAJ J. Soutendam (Ret)1300 Steeles Ave EastBrampton, Ontario, CanadaL6T IA2

Canadian Forces Med Ln OffCanadian Defence Ln Staff2450 Massachusetts Ave, NWWashington, DC 20008

Commanding Officer404 Maritime Training SquadronCanadian Forces Base GreenwoodGreenwood, N.S. BOP 1NO CanadaATIN: Aeromed Tng Unit

Officer CommandingSchool of Operational and

Aerospace MedicineDCIEMPO Box 20001133 Sheppard Avenue WestDownsview, Ontario, CanadaM3M 3B9

38

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