REPORTDOCUMENTATIONPAGEFormApprovedOMBNo.0704-0188Thepublicreportingburdenforthiscollectionofinformationisestimatedtoaverage1hourperresponse,includingthetimeforreviewinginstructions,searchingexistingdatasources,gatheringandmaintainingthedataneeded,andcompletingandreviewingthecollectionofinformation.Sendcommentsregardingthisburdenestimateoranyotheraspectofthiscollectionofinformation,includingsuggestionsforreducingthisburden,toDepartmentofDefense,WashingtonHeadquartersServices,DirectorateforinformationonOperationsandReports(0704-0188),1215JeffersonDavisHighway,Suite1204,Arlington,VA22202-4302.Respondentsshouldbeawarethatnotwithstandinganyotherprovisionoflaw,nopersonshallbesubjecttoanypenaltyforfailingtocomplywithacollectionofinformationifitdoesnotdisplayacurrentlyvalidOMBcontrolnumber.PLEASEDONOTRETURNYOURFORMTOTHEABOVEADDRESS.1.REPORTDATE(DD-MM-YYYY)10-04-20082.REPORTTYPEFINAL3.DATESCOVERED(From-To)4.TITLEANDSUBTITLETestOperationsProcedure(TOP)7-3-057Pitot-StaticSystemCalibrations5a.CONTRACTNUMBER5b.GRANTNUMBER5c.PROGRAMELEMENTNUMBER6.AUTHORS5d.PROJECTNUMBER5e.TASKNUMBER5f.WORKUNITNUMBER7.PERFORMINGORGANIZATIONNAME(S)ANDADDRESS(ES)U.S.ArmyAviationTechnicalTestCenter(TEDT-AC-CO)Building30601,PetersStreet,CairnsArmyAirfieldFortRucker,AL36362-52768.PERFORMINGORGANIZATIONREPORTNUMBERTOP7-3-0579.SPONSORING/MONITORINGAGENCYNAME(S)ANDADDRESS(ES)TestBusinessManagementDivision(TEDT-TMB)USArmyDevelopmentTestCommand314LongsCornerRoadAberdeenProvingGround,MD21005-505510.SPONSOR/MONITORSACRONYM(S)U.S.ArmyAviationTechnicalTestCenter11.SPONSOR/MONITORSREPORTNUMBER(S)Sameasitem812.DISTRIBUTION/AVAILABILITYSTATEMENTApprovedforpublicrelease,distributionunlimited.13.SUPPLEMENTARYNOTESDefenseTechnicalInformationCenter(DTIC),ADNo.:14.ABSTRACTThisTestOperationsProcedure(TOP)describesthetestrequirements,objectives,responsibilities,andtechniques/methodologiesrequiredtoperformpitot-staticsystemcalibrations.ThisTOPisusedforrotary-wingandfixed-wingaircraft.TheTOPwillfacilitatetestplanning,execution,anddatacollectionusingtwotechniques(trailingdeviceandpace)andtheequipmentrequiredtocompletepitot-staticsystemcalibrations.VariationsinplatformrequirementsarediscussedwithinthisTOP.Theseguidelines,alongwithplatformspecificcapabilitiesandrequirements,willenablethetestertodevelopacomprehensivetestingstrategy.15.SUBJECTTERMSRotary-WingAircraftFixedWingAircraftAirspeedCalibrationPitot-StaticCalibration16.SECURITYCLASSIFICATIONOF:17.LIMITATIONOFABSTRACTSAR18.NUMBEROFPAGES2619a.NAMEOFRESPONSIBLEPERSONa.REPORTUnclB.ABSTRACTUnclC.THISPAGEUncl19b.TELEPHONENUMBER(includeareacode)StandardForm298(Rev.8-98)PrescribedbyANSIStd.Z39-18

USARMYDEVELOPMENTALTESTCOMMANDTESTOPERATIONSPROCEDURE

*TestOperationsProcedure(TOP)7-3-05710April2007DTICADNo.:

PITOT-STATICSYSTEMCALIBRATIONSPageParagraph1.SCOPE......................................................................................11.1Introduction..............................................................................11.2TrailingDeviceMethodologyTheory......................................11.3PaceMethodologyTheory.......................................................12.FACILITIESANDINSTRUMENTATION............................32.1Facilities...................................................................................32.2Instrumentation.........................................................................53REQUIREDTESTCONDITIONS..........................................73.1TrailingDeviceTestPlanning..................................................73.2PaceTestPlanning...................................................................74.TESTPROCEDURES..............................................................94.1General.....................................................................................94.2TrailingDeviceTechnique.......................................................94.3PaceTechnique.........................................................................125.DATAREQUIRED..................................................................156.PRESENTATIONOFDATA..................................................17

APPENDIXA.TRAILINGDEVICEFIGURES..............................................A-1B.SAFETY/RISKMANAGEMENT...........................................B-1C.EXAMPLEAIRSPEEDCALIBRATIONDATACARDS.........................................................................C-1D.DATAREDUCTION...............................................................D-1E.EXAMPLEDATAPRESENTATION....................................E-1F.GLOSSARY.............................................................................F-1G.REFERENCES.........................................................................G-1

Approvedforpublicrelease;distributionunlimited.

TOP7-3-05710April2008

1.SCOPE.

1.1Introduction.

Thispitot-staticTestOperationsProcedure(TOP)isusedforrotary-wingandfixed-wingaircraft.TheTOPwillincludetwotechniques(trailingdeviceandpace)andtheequipmentrequiredtocompletepitot-staticsystemcalibrations.ThisTOPwillfacilitatetestplanning,execution,anddatacollection.VariationsinplatformrequirementsarediscussedwithinthisTOP.Theseguidelines,alongwithplatformspecificcapabilitiesandrequirements,willenablethetestertodevelopacomprehensivetestingstrategy.

1.2TrailingDeviceMethodologyTheory.

ThetrailingdevicemethoddiscussedinthisTOPisrestrictedtorotary-wingaircraft.Thismethodrequiresacalibratedpitot-staticsource(trailingdevice)tobesuspendedbelowtheaircraftonacable.Theaircraftbeingcalibratedwillperformaspeedsweepunderpreplannedconditions.Possibleconditionsinclude:levelflight,climbs,descents,externalconfigurationchanges,andchangesinsideslip.Thecalibratedpitot-staticdataarethencompareddirectlytotheaircraftpitot-staticdatacollected.Theairspeedandaltimeterpositionerrorcorrectionsforagivenflightconditionaredeterminedbysubtractingthesourceairspeedandaltitudefromtheairspeedandaltitudeindicatedbytheaircraftpitot-staticsystem.Thetrailingdeviceshouldbesuspendedoutsidethedownwashoftheaircraft(minimumof11/2to2rotordiameters).Thepressuresfromthetrailingdevicearetransmittedthroughtubestothehelicopterwheretheyareconvertedtoaccuratepressurealtitudesandcalibratedairspeedsbysensitive,calibratedinstruments.Sincethepressuresfromthesourcearetransmittedthroughtubestothehelicopterforconversiontoairspeedsandaltitudes,noerrorisintroducedbytrailingthesourcebelowthehelicopter.

1.3PaceMethodologyTheory.

ThepacemethoddiscussedinthisTOPcanbeusedforbothrotary-wingandfixed-wingaircraft.Thismethodrequiresasecondaircraftwithacalibratedpitot-staticsystemtoflyincloseformationwiththeaircraftundertest.Theaircraftbeingcalibratedwillperformaspeedsweepunderthepreplannedconditionsastheformationlead.Theflightformationwillbecloseenoughtoaccuratelyperceiveposition,rateofclosure,orseparation,butoutsidetheflowfield(downwashandvortices)oftheaircraftundertest.Bothaircraftareflownatthesamealtitudesothatbothairspeedandaltitudedatacanbecollected.Theconditionsflownmaybelimitedbythecapabilitiesofthedifferentaircraft.Thecalibratedpitot-staticdataarecompareddirectlytothetestaircraftpitot-staticdatacollected.Theairspeedandaltimeterpositionerrorcorrectionsforagivenflightconditionaredeterminedbysubtractingthecalibratedairspeedandaltitudefromtheairspeedandaltitudeindicatedbythetestaircraftpitot-staticsystem.

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2.FACILITIESANDINSTRUMENTATION.

2.1Facilities.

2.1.1TrailingDeviceEquipment.

Thetrailingdevicecalibrationsystemconsistsofthefollowingcomponents:

a.TrailingDevice.AtypicaltrailingdeviceisshowninfigureA-1(AppendixA).Thecableattachmentbracketandpivotpinarelocatedsothat,whenthedeviceissuspendedbythepivotpin,thedevicehangshorizontallyorslightlynosedown.Thepivotpingoesthroughtheeyeletofthecable.Thedevicehasfourfinsattheextremerear,oriented45degreesfromthevertical,sothatnofinisdirectlybehindthecableattachmentbracket.Thepitotandstaticportsareconnectedbysurgicaltubingtothesemirigidtubingofthecableandtubingassembly.Itisimportantthatthesurgicaltubingberoutedbehindthepivotanduptothesemirigidtubing.Thetrailingdevicecalibrationisdeterminedthroughwindtunneltesting.Thetrailingdeviceshouldbestoredbetweenusesinaprotectivecasetopreventnicksandscrapes.

b.CableandTubingAssembly.

Thecableis3/16-in.,7-by19-twistedstrand,4,200-lbtensilestrengthstainlesssteelcable.Ateachend,thecableisloopedaroundaneyeletandsecuredwithtwofittings.Theeyeletcenter-to-eyeletcenterlengthisdeterminedasafunctionoftherotordiameter.Thecableshouldbenoshorterthan11/2to2timestherotordiameter.Cablesshorterthanthislengthwillcausethetrailingdevicetoremainwithinthedownwashoftherotor,contributingtopositionerrorofthetrailingdeviceandaerodynamicinstability.Cableslongerthanthelengthidentifiedleadtoagreaterchanceofinstabilityatlowerairspeeds.

Thepitotandstaticlinesare3/16-in.outsidediametersemirigidtubing.Thetubingissecuredtothecableandisinatriangularconfiguration.Thecableformstheleadingedgewiththetwotubessidebysidebehindthecable.Thetop6to8feetofthecableandtubingassemblymaybewrappedwithaprotectivematerialsuchaselectricaltapetominimizedamagecausedbychaffingagainsttheaircraft.

c.Attachment/ReleaseSystem.

Theattachmentsystemisdependentontheaircraftandtheonboardsystems.Theattachmentsystemmustsecurelyholdthetrailingdevice,cable,andtubingtotheaircraftthroughouttheflight.Thekeycomponentoftheattachmentsystemistheslipfitting.Polyflowtubingisinstalledovertheslipfittings.Ifthecableisreleased,theslipfittingwillreleasethetubing.

Thereleasesystemisdependentontheaircraftandtheonboardsystems.Thereleasesystemmustbeabletojettisonthetubing,cable,andtrailingdevicereliablyandrapidly.

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Examplesofpreviousattachment/releasesystems:

(1)OntheOH-58D,AH-64D,andAH-6M,theattachment/releasesystemusedwastheweaponspylon.Theassemblywasmountedtoaheavyplatethatwasjettisonedbythewingstoresjettison(FiguresA-2andA-3).

(2)OntheHH-60G,theattachment/releasesystemusedwasthecargohook.Theslipfittingswerelocatedonthehook.Thereleasesystemwasthatofthecargohook.

(3)OntheCH-47D,theattachment/releasesystemusedrequiredamanualrelease.Frameworkwasmountedtothecentercargoholethatcontainedahandlevertoreleasetheassembly(FiguresA-4andA-5).

d.SensitiveAirspeedandAltimeterIndicators.

Thesensitiveairspeedindicatorsshouldhave1-ktdivisionsfromzeroto100ktand2-ktdivisionsabove100kt.Thisallowsreadingtothenearestone-halfknotfromzeroto100ktandtothenearestknotabove100kt.Sensitivealtimetersshouldhave20-ftdivisions.Thisallowsreadingtothenearest10ft.

e.GroundHandlingEquipment.

Thelaunch/recoverypersonshouldwearhearingandeyeprotectiontopreventinjuryfromdownwashandnoise.Therecoverypersonshouldwearheavyrubberglovestopreventinjuryfromthepossibilityofstaticelectricaldischarge.

2.1.2PaceEquipment.

Thepacecalibrationsystemconsistsofaspeciallyoutfittedandcalibratedpaceaircraft.Thesepaceaircraftgenerallyhavespeciallydesigned,separatepitot/staticsystemswhichhavebeencalibratedwiththemostprecisemethodsavailable.Thesensitiveairspeedandaltimeterindicatorsshouldbeheldtothestandardsdiscussedforthetrailingdeviceindicators(seeparagraph2.1.1d).

2.2Instrumentation.

2.2.1IndicatorSensitivityandCalibration.

Allairspeedandaltitudeindicatorsbeingusedforthecalibrationeffortshouldreceiveacalibrationtoattaintheinstrumentcorrectionsneededfordatareduction.Theinstrumentcalibrationwillidentifythedeltabetweentheairspeed/altitudecalibrationinputsetpointandtheairspeed/altitudeindicated.Whenperforminghysteresiscalibrations,theindicatorsmustbeputonashakerortappedconstantlytosettleout.

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Sensitiveairspeedindicatorsshouldhave1-ktdivisionsfromzeroto100ktand2-ktdivisionsabove100kt.Thisallowsreadingtothenearestone-halfknotfromzeroto100ktandtothenearestknotabove100kt.Thecalibrationshouldbeaccomplishedin5-ktincrementsincreasingfrom20kttothemaximumallowableairspeed.Hysteresisshouldbecheckedbyreducingairspeedsfromthemaximum.Allowablehysterisisis1ktbelow100ktand2ktabove100kt.

Sensitivealtimetersshouldhave20-ftdivisions.Thisallowsreadingtothenearest10feet.Startingatsealevel,increaseindicatedaltitudeto5,000ftin500-ftincrements.Recordinputandobservedaltitudesateachincrement.Increasealtitudeto15,000feetin1,000-ftincrements.Reduceinputaltitudestoppingatthesamepointsgatheredgoingup;recordinputandoutputaltitudesateachincrement.Allowablehysteresisis20feet.SeeFederalAviationRegulationsFARPart43AppendixE-AltimeterSystemTestandInspectionforgeneralmethodsandprocedures1*.

2.2.2LeakChecks.

Ensurethepitot-staticleakcheckequipmentcalibrationrangeiswithinthepressurerangesoftheindicatorsbeingcalibrated.

Allowableleakratesforacompletetrailingdevicesysteminstalledonanaircraftare2.0kt/minat100ktaftertappingtheairspeedindicatorand20fpmat1,000feetaboveambientaftertappingthealtimeter.

2.2.3AirspeedSystemDynamicResponseandPitot/StaticBalance.

Ifclimbanddescentperformancedataaretobecollected,thenthepitot/staticsystemneedstobebalanced.Tocheckthebalance,attachafixturetothetrailingdevicethatventsthepitotandstaticportstogether.Applyapressurechangetosimulate3,000feetperminuteclimbrate.Airspeedshouldnotchangemorethan15ktatthepointofprimarymeasurement,inthiscasethetrailingdeviceairspeedindicator.Adjustthebalancebyaddingvolumetothepitotorstaticsideasnecessary.Thelocation,size,andconfigurationoftheballastwillaffectthedynamicresponsethroughoutthesystem.Note:15ktatzeroairspeedisapressuredifferentialequivalenttoabout1knoterrorat100kt.Thesameconsiderationsholdtrueforanair-data/noseboominstallation.

Addinginstrumentationtransducers(thusvolume)totheprimaryaircraftpitot/staticsystemcanaffectthebalanceofthesystemundertest.Performabalancetestbeforeandafteramodificationifclimbanddescentdataaretobecollected.Inthiscase,theobjectistomaintaintheoriginalaircraftsystembalanceattheprimaryairspeedinstrumentregardlessofitsvalue.

*SuperscriptnumberscorrespondtothoseinAppendixG,References.

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3.REQUIREDTESTCONDITIONS.

3.1TrailingDeviceTestPlanning.

Alargenumberofdatapointscanbeobtainedinarelativelyshorttimebyusingthetrailingdevicemethodofpitot-staticsystemcalibration.Datacanbeobtainedduringlevel,climbing,anddescendingflight.

Thetrailingdeviceisasensitiveinstrumentandmustbehandledandstoredwiththegreatestcare.Duringlaunchandretrieval,thedevicemustnotbeallowedtotouchtheground;evensmallnicksorscratchescanchangeitscalibration.Thetrailingdevice,cableandtubingassembly,andindicatorsmustalwaysbestoredintheboxesprovidedandmustnotbesubjectedtoadamp,dusty,corrosive,orotherwisehostileenvironment.

Calibrationsheetsshouldbeobtainedforthetrailingdeviceandeachindicator,andthecalibrationsmustmeettheacceptancerequirements.

Oncethetrailingdeviceisinstalled,ensurethatboththetrailingdeviceandaircraftsystem(s)undertestpassapitot-staticleakcheck.Thecableshouldbenoshorterthan11/2to2timestherotordiameterofthetestaircraft.

Takespecialcaretoensurethatthecompletereleasesystemfunctionsproperlyandthatthecableandtubingassemblycannotjamorhangupwiththecablebeingpulledinanydirection.

Schedulethetestaircraftandthechaseaircraftfortesting.Ifpossible,useachaseaircraftsimilarinperformancetothetestaircraft.Schedulearadiofrequencythatwillallowlaunchandretrievalpersonneltousehandheldradiostotalkwithcrewsofthetestandchaseaircrafttoenhancesafety.Ensurethetestaircrafthasout-of-groundeffecthoverperformanceavailableduringlaunchandretrievalofthetrailingdevice.Thetrailingdevicemustbelaunchedandrecoveredatalocationclearofbuildingsandotheraircraft.Schedulethetestaircraftcrew,chaseaircraftcrew,andgroundcrewforapreflightbriefingtodelineatedutiesduringtheflight.

3.2PaceTestPlanning.

Alargenumberofdatapointscanbeobtainedinarelativelyshorttimebyusingthepacemethodofpitot-staticsystemcalibration.Datacanbeobtainedduringlevel,climbing,anddescendingflight.

Schedulethetestaircraft,paceaircraft,andchaseaircraftfortesting.Thetestaircraftandpaceaircraftmusthavesimilarperformancefortheflightregimesbeingcalibrated.Ifpossible,useachaseaircraftsimilarinperformancecapabilities.Schedulearadiofrequencyforcommunicationbetweenthethreeaircraft.Schedulethetestaircraftcrew,paceaircraftcrew,andchaseaircraftcrewforapreflightbriefingtodelineatedutiesduringtheflight.

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4.TESTPROCEDURES.

4.1General.

Thecalibrationofpitot-staticpressuresystemscanbeaccomplishedbydeterminingtheerrorsineachsystemindependentlyorsimultaneously.Theproceduresdiscussedinthissectioncouldbeusedtocollectdataoneachsystemundertest.Eachtechniquehasparticularsafetyconsiderations.RisksforeachtechniquehavebeenidentifiedinappendixB.

4.2TrailingDeviceTechnique.

4.2.1PreflightBriefing.

Thepreflightbriefingshouldhavethetestaircraftcrew,chaseaircraftcrew,andthelaunchandrecoverygroundcrewinattendance.Thepreflightbriefwillcoverthedutiesofeachcrewduringtheflight.Thesubjectsshouldincludebutarenotlimitedtothefollowing:

a.Radiofrequenciestobeusedduringlaunch,recovery,andin-flight.

b.Launchandrecoveryprocedurestoincluderadiocommunicationsandpersonnelresponsibilities.Thetrailingdevicemustbelaunchedandrecoveredatalocationclearofbuildingsandotheraircraft.Minimizetheriskofaccidentandinjury.Thetrailingdeviceshouldnottouchthegroundandshouldbeheldbythelaunch/recoverypersonduringliftoffandlanding.

c.Briefthecrewofthechaseaircrafttoassistinlaunchandrecoveryeffort.

d.In-flighttestingprocedurestoincluderadiocommunications,conditionstobetested,anddatapointorder.

e.Briefthecrewofthechaseaircrafttomonitormotionandpositionofthetrailingdevicerelativetotestaircraftthroughouttheflight.

f.Briefthecrewofthechaseaircrafttopositionthechaseaircraftforbestsurveillanceofthetestaircraft,cableandtubingassembly,andtrailingdeviceconsistentwithsafetyofthechaseaircraft.

4.2.2PreflightInspection.

Thecompletesystemmustbethoroughlyinspectedbeforeuse.Thepreflightinspectionincludes:

a.Checktrailingdevicenosefornicksandscrapes(evensmallnicksnearthestaticportscanchangethecalibrationofthedevice.)

b.Checkpitotandstaticportsareclearofanyobstructions.

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c.Checkthefinsforproperalignment(straight).

d.Ensureallfastenersofthedevicesegmentsaretightandsecuredwithadhesive/sealant.

e.Inspectcableforfraying,especiallyattheends.

f.Checkcableeyeletsandfittingsareinplaceandundamaged.

g.Verifylacingissnugandattheproperspacing.

h.Checkthepneumaticlinesnearthereleasemechanismandnearthedevicedonotkinkwhenthecableandtubingassemblyispulledafttothein-flightposition.

i.Checkthatthereleasemechanismcanreleasethecablewiththecablepulledatanyanglewithsubstantialforce(i.e.,thecablewillnothang-upwhenthereleasemechanismisactivated).

j.Verifytheairspeedandaltimeterindicators/instrumentationhavecurrentcalibrations.

k.Verifythepitot-staticsystem(s)tobecalibratedandthetrailingdevicesystemhavebeenleakchecked.

4.2.3LaunchProcedures.

Usethefollowingprocedurestolaunchthetrailingdevice:

a.Thecableandtubingassemblywillbestretchedonthegroundtothefrontoftheaircraft(directlyoffthenoseorto45degreesoffthenose)withinthepilotsview.Thelaunchpersonnelshouldbeholdingthetrailingdevicebeforetheaircraftliftsofftheground.

b.Verifycommunicationswiththechaseaircraftandspotterbeforelift-off.Thelaunchandrecoverypersonnelrelyonthespottertoaborttheprocedureifunsafecircumstancesarise.Thespottershouldremainincommunicationwiththetestaircraftwhileobservingthelaunchandrecoverypersonnel.

c.Atlift-off,thetestaircraftwillslowlyascendverticallyasthelaunchpersonnelwalktowardtheaircraft.Thelaunchpersonnelwillcarrythetrailingdevicebeneaththeaircraftandallowtheaircrafttoliftthetrailingdeviceclearofhis/hergrasp.

d.Thespotterwilluseradiocommunicationwiththetestaircrafttocallouttheheightofthedevice.

e.Oncethetrailingdevicehasbeenreleased,theaircraftwillcontinuetoascendverticallytoasafehoverheight.Atthesafehoverheight,allowthecabletountwistandthetrailingdevicetostopspinningbeforetransitioningtoforwardflight.

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f.Aftertransitiontoforwardfight,followthejoin-upprocedurediscussedinthebrieftojoin-upwiththechaseaircraft.

4.2.4In-FlightProcedures.

Usethefollowingprocedurestoobtaindata:

a.Setaltimetersto29.92in.-Hg.

b.Stabilizethetestaircraftandtrailingdeviceatthedesiredtestpoint.

c.Withtheaircraftandtrailingdevicestabilizedatthedesiredtestpoint:

(1)Operateinstrumentationrequiredtorecorddata.

(2)Ifusingananaloggauge,tapindicatortominimizetheeffectsoffriction,backlash,andhysteresis.

(3)Readandrecordindicationsofallpitot-staticinstrumentsasquicklyaspracticable.

d.Thechaseaircraftwillmaintainobservationofthetrailingdevicefromthelaunchthroughrecovery,informingthetestaircraftofchangesintrailingdevicestability.

4.2.5RecoveryProcedures.

Usethefollowingprocedurestorecover:

a.Verifyrecoverypersonnelandspotterareinplaceandpreparedforrecovery.Therecoverypersonnelshouldbewearingtheprotectivegearandhavethegroundinghookready.Thespottershouldhaveradiocommunicationswiththetestarticle.

b.Bringtheaircrafttoahighhoverwiththespottercallingoutthetrailingdeviceheight.

c.Thespotterwillmarshaltheaircraftovertheretrievalpersonnel.

d.Slowlydescendverticallyuntiltheretrievalpersonnelcatchesthetrailingdevicewiththegroundinghooktodissipatethestaticelectricityfromthetrailingdeviceandcable.

e.Whentheretrievalpersonhascontrolofthetrailingdevice,theaircraftwillcontinuetodescendslowly.Theretrievalpersonwillwalkawayfromtheaircraft,keepingthecableandtubingassemblyfrombeingdraggedandclearoftheaircraft.

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4.3PaceTechnique.

4.3.1PreflightBriefing.

Thepreflightbriefingshouldhavethetestaircraftcrew,chaseaircraftcrew,andpaceaircraftcrewinattendance.Thepreflightbriefwillcoverthedutiesofeachcrewduringtheflight.Thesubjectsshouldincludebutarenotlimitedtothefollowing:

a.Radiofrequenciestobeusedduringlaunch,recovery,andin-flight.

b.Launchandrendezvousprocedures.

c.Formationprocedures.

d.In-flighttestingprocedurestoincluderadiocommunications,conditionstobetested,anddatapointorder.

e.Briefthecrewofthechaseaircrafttomonitormotionandpositionchangesbetweenthepaceaircraftandthetestaircraft.

f.Briefthecrewofthechaseaircrafttopositionthechaseaircraftforbestsurveillanceoftheaircraftrelativepositions.

4.3.2PreflightInspection.

Thecompletesystemmustbethoroughlyinspectedbeforeuse.Thepreflightinspectionincludes:

a.Checkpitotandstaticportsareclearofanyobstructions.

b.Verifytheairspeedandaltimeterindicators/instrumentationhavecurrentcalibrations.

c.Verifythetestandpacepitot-staticsystemshavebeenleakchecked.

4.3.3In-FlightProcedures.

Usethefollowingprocedurestoobtaindata:

a.Setaltimeterintestandpaceaircraftto29.92in.-Hg.

b.Stabilizetheleadaircraftatthedesiredtestpoint.Communicatetothesecondaircraftwhenapproachingstable.

c.Whentheleadaircraftcallsapproachingstable,thesecondaircraftshouldtightentheformationtothebriefedseparation(formationseparationdistancesbetweendatapointscanbeincreasedtoreducepilotworkload).

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d.Theleadaircraftwillcommunicatewhenstable.Thesecondaircraftwillcommunicatewhentostartthedatacollectionafteritisstablewiththeproperseparationandwithoutaclosure/separationratefromtheleadaircraft(boththetestaircraftandthepaceaircraftshouldbeatthesamealtitude).

e.Withbothaircraftstabilizedatthedesiredtestpoint:

(1)Operateinstrumentationrequiredtorecorddata.

(2)Ifusingananaloggauge,tapindicatortominimizetheeffectsoffriction,backlash,andhysteresis.

(3)Readandrecordindicationsofallpitot-staticinstrumentsasquicklyaspracticable.

5.DATAREQUIRED.

Arepresentativeflightdatacardforacquiringpitot-staticdatausingacalibratedpitot-staticsystemispresentedinAppendixC.Thedatacardispresentedasanexampletoillustratethedataacquisitionprocedure.Thedatacardusedinagivencalibrationmaydifferindetailsfromthisexample.Thedatatobecollectedin-flightincludeairspeedandaltitudeofboththecalibratedsystemandsystemundertest.Outsideairtemperature,sideslipangle,aircraftconfiguration,andflightregimedataarealsorequiredtocompletethedatacollection.Caremustbetakentoensurethatoperatorsmanualairspeedlimits,presentedintermsofshipsystemairspeed,arenotexceeded.Whenusingmultiplepositionerrorcorrections,aminimumoftwooverlappointsshouldbeusedtoensurecorrelation.Anexampleofmultiplepositionerrorcorrectionswouldbetheuseofatrailingdevicetocalibrateairspeedsfrom40to120ktandthepacemethodusedtocalibratefrom110to170kt.Asecondexamplewouldbeifthepaceaircrafthadmultiplepositionerrorcorrectionsformultipleconfigurationstobeused(landinggearup/down,flapsup/down,etc.).ThedatareductionprocedureispresentedinAppendixD.

6.PRESENTATIONOFDATA.

Datashouldbepresentedinsuchawayastoidentifythedifferencebetweenindicatedairspeedandcalibratedairspeedforeachconfigurationandpitot-staticsystembeingcalibrated.ResultscanbepresentedintheformatfoundinFigureE-1(AppendixE).Theplotidentifiestheconditionsthatthedatawereflown,theconfiguration,andtheindividualpitot-staticsystem.Calibrationplotssimilartotheexamplewouldneedtobeproducedforeachsystemcalibrated.Theexampleplotisthecalibrationforaircraftpitot-staticsystem.Ifanon-standardpitot-staticsystem(instrumentedboommountedontheaircraftfortestpurposes)isbeingcalibratedandreportedon,precautionsneedtobemadetoensurethecalibrationinformationfromthenon-standardinstallationisnotusedforthestandardsystemoperatormanualcorrections.ANOTFORHANDBOOKUSEnoteshouldbeplacedonanynon-standardinstallationplots.

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APPENDIXA.TRAILINGDEVICEFIGURES.

FigureA-1.TrailingDevice

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Breakawaypoint,pitotandstaticlinesslideovercoppertubing.

FigureA-2.AH-64WeaponsPylonMount

FigureA-3.AH-64WeaponsPylonMount(bottom)

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Breakawaypoint,pitotandstaticlinesslideovercoppertubing

ReleasePin

CableEyelet

FigureA-4.CH-47DAttachment/ReleaseSystem(bottomoftheaircraft)

Safetywirereleasehandle

Pitotandstaticlinestoindicators

FigureA-5.CH-47DAttachment/ReleaseSystem(Cabin)

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APPENDIXB.SAFETY/RISKMANAGEMENT.

1.1GeneralThehighestlevelofconcernforsafetyshouldbemaintainedthroughoutthetestprogram.Humanandmaterielresourcesshouldbeprotectedandconservedbytheearlyidentification,evaluation,andcorrectionofanysystemhazardsthatmayappearduringtheconductofthesetests.Hazardsidentifiedduringthesafetytestingshouldbeclassifiedastoseverityandprobabilityinaccordancewith(IAW)MIL-STD-882D2.Thehazardsidentifiedinthissectionarethetypicalhazardsinperformingthesetests.Eachcalibrationperformedshouldbeevaluatedforthepossibilityofadditionalhazards.Thetestteamshouldincorporateagradualbuildupinalltestmaneuversandshouldevaluatetrendstopreventexceedingaircraft-ortest-imposedlimits.Specificvariablesaffectingsafetyarediscussedinthissection.1.2Training/CurrencyThecrewwillconsistoftwoqualifiedandcurrentexperimentaltestpilots.Additionalcrewshouldbeminimizedinaccordancewithaircraft,safety,ordatacollectionrequirements.1.3AircraftThetestdirector(TD)willinspectthetestaircrafttoensureingress/egressroutesarenotimpairedbyequipmentinstallation.Allcrewmemberswillperformegressdrillsbeforethestartofthetest.Aqualityassuranceinspectorwillinspectallnonstandarditemsinstalledonthetestaircraftbeforestartofthetest.1.4RisksIdentifiedforUseoftheTrailingDevice1.4.1InjurytoGroundCrewDuringLaunchandRecoveryoftheTrailingPitot-StaticDeviceDuringlaunchandrecovery,thepitot-staticdeviceapparatusishandledbygroundpersonneltoensurethatthepitot-staticdevicedoesnotcontacttheground.Groundpersonnelcouldbestruckbythepitot-staticdeviceduringrecoveryorcouldbecomeentangledinthecablingduringlaunchorrecoveryoperations.Inaddition,groundpersonnelcouldbeinjuredbyahighvoltagedischargefromthepitot-staticdevice(duetostaticelectricalbuildup)duringrecovery.Suggestedactionstakentomitigatetherisk.(a)Abriefingofproceduresshouldbeconductedbeforeflight.(b)Thegroundcrewshouldwearflighthelmetsandgloves.(c)Thepersondesignatedtoretrievethepitot-staticdeviceduringrecoveryshouldwearheavyrubberglovestoprotectfromstaticelectricityandshoulduseagroundedhooktodischargethestaticelectricity.(d)Anobserveronthegroundshouldbeinradiocontactwiththeflightcrewduringlaunchandrecoveryoperations.

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1.4.2DamagetoAircraftduetoContactwiththeTrailingPitot-StaticDeviceAssemblyDuringIn-FlightOperationsEachuseofthetrailingdevicemustbeconsideredanewdevelopment.Smalldifferencesinattachmentandhandlinghavecausedlargedifferencesinthestabilityofthetrailingdevice.Theonsetofuncontrolledmotionofthetrailingdevice,cable,andtubingassemblyisoftenrapidandoccurswithlittlewarning.Theresultsofthisuncontrolledmotioncanbeserious.Ifthetrailingdeviceseparatesfromthecable,thecablecanbecomeentangledinthemainortailrotor.Thetrailingdevicealsocandeveloposcillationsgreatenoughtocausecontactwiththeaircraft.Thetrailingdeviceissensitivetoturbulencewhereuncontrolledmotionofthetrailingdeviceandcableassemblycouldoccurwithoutanypriorindication.Suggestedactionstakentomitigatetherisk.(a)Avisualchaseishighlysuggested.Thechaseaircraftshouldbepositionedsuchthatitwouldnotbestruckbythetrailingdeviceorbecomeentangledwiththecableandtubingassemblyshouldthetrailingdevicehappentodisintegrateorseparatefromthecableorifthetrailingdeviceandcableandtubingassemblyarejettisoned.Thechaseaircraftshouldnotbepositionedbehindorbelowthetestaircraft.(b)Thechaseaircraftshouldmaintainapositionthatallowsthebestobservationofthetestaircraft,cableandtubingassembly,andtrailingdeviceinaccordancewiththesafetyrequirementsabove.(c)Thecableandtubingassemblyshouldbewatchedcloselybythechaseflightcrewtodetecttheonsetofwhippingmotions.Whippingofthecableandtubingassemblyisusuallyapreludetotrailingdeviceinstability.(d)Thetrailingdeviceshouldbewatchedcloselytodetecttheonsetofanyrolling,pitching,verticaloscillation,orforeandaftoscillations.Attheonsetofanyofthesemotions,thechaseaircraftcrewshouldadvisethetestaircraftcrewimmediately.(e)Thetestaircraftshouldnotengageinanymaneuveringflightwhentowingthetrailingdevice.(f)Theflightcrewshouldthoroughlybrieftheemergencyprocedurestoincludecrewcoordinationdutiesassociatedwiththemalfunctionofthetrailingdeviceassemblybeforeflight.(g)Testingshouldbeconductedonlyinsmoothairconditions.1.4.3DamagetoAircraftduetoContactoftheTrailingPitot-StaticDeviceAssemblywithanObstacleDuringTransitionfromLaunchandRecoveryWhenthetrailingdeviceislaunchedorrecovered,theaircraftwillascend/descendvertically.Theaircraftwilltransitionbetweenahighhoverandforwardflightorbetweenforwardflightandahighhoverasthesituationrequires.Thepotentialexistsforaninadvertentcontactofthetrailingdevicewithanobstacleduringthesetransitionswhenflyingneartheground.Suggestedactionstakentomitigatetherisk.

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(a)Avisualchaseishighlysuggested.Thechaseaircraftshouldmaintainapositionthatallowsthebestobservationofthetestaircraft,cableandtubingassembly,andtrailingdevice.(b)Theflightcrewshouldthoroughlybrieftheemergencyprocedurestoincludecrewcoordinationdutiesassociatedwiththemalfunctionofthetrailingdeviceassemblybeforeflight.1.5RiskIdentifiedforUseofPace1.5.1MidairCollisionwithPaceAircraftPaceoperationswillplacetwoaircraftincloseproximity.Thepotentialexistsforinadvertentcontactbetweenaircraft,resultinginlossofthetestaircraftorpaceaircraftand/orinjuriestothecrewduetothepossibilityofoneorbothaircraftbeingunabletorecover.Suggestedactionstakentomitigatetherisk.(a)Athoroughbriefingoftheflightmaneuvers,abreakawaybriefing,andcommunicationproceduresshouldbeconductedwithallcrewspresentbeforeeachflight.(b)Paceaircraftshouldbeflownbyaqualifiedandcurrentpilottrainedtoperformpaceprocedures.(c)Two-waycommunicationbetweenaircraftshouldbemaintainedatalltimes.

B-3

SETALTIMETERTO29.92!!!!!Chase:xxxFltNo:xxDate:x/x/20xxPage1of1Freq:xxx.x,xxx.xEvtPtStartTimeTrailingShipDevicektftktftOATPtConfiguration1TestCondition1HouseKeepingLevelFlight5000ftBoomAltitude240ktBoomAirspeed350ktBoomAirspeed460ktBoomAirspeed570ktBoomAirspeed680ktBoomAirspeed790ktBoomAirspeed8100ktBoomAirspeed9110ktBoomAirspeed10120ktBoomAirspeed11115ktBoomAirspeed12105ktBoomAirspeed1395ktBoomAirspeed1485ktBoomAirspeed1575ktBoomAirspeed1665ktBoomAirspeed1755ktBoomAirspeed1845ktBoomAirspeedTOP7-3-05710April2008

APPENDIXC.EXAMPLEAIRSPEEDCALIBRATIONDATACARDS.

C-1

DataReferenceCalibratedPitot-StaticSourcePitot-StaticSourceUnderTestPositionError(1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)Pt1Evt2Vind3Vic4Vic5Vpc6Vcal7VindVicVicVpcTOP7-3-05710April2008

APPENDIXD.DATAREDUCTION.

Arepresentativetableforreducingpitot-staticdataacquiredusingacalibratedsystemispresentedintableD-1.Thisformispresentedasanexampletoillustratethedatareductionprocedure.Theformusedforreducingdatafromagivencalibrationmaydifferindetailsfromthisexample.Theexampletableissetupforasinglecalibratedsourceandasinglesourceundertest.Theprocessremainsthesameformultiplesources.TheoryanddefinitionsaredetailedintheU.S.NavalTestPilotSchool-FlightTestManualNo.1063.Theatmosphericconstantsdefinewithinthissectionpertaintothe1962U.S.StandardAtmosphere4.

TableD-1.Pitot-StaticSystemCalibrationDataReductionProcess

NOTES:1PtPoint(fromthetestdatacard)2EvtEvent(fromthetestdatacard)3Vindindicatedairspeed4Vicinstrumentcorrectionairspeeddelta5Vicinstrumentcorrectedairspeed6Vpcpositioncorrectionairspeeddelta7Vcalcalibratedairspeed

Step1

Transcribereadingsfromthedatacardtothedatareductiontablecolumns(1),(2),(3),and(8).

Step2

Calculateinstrumentcorrectedairspeedforallpitot-staticsystemsforeachtestpointasfollowsandenterinViccolumns(5)and(10):Vic(5)=Vind(3)+Vic(4)Vic(10)=Vind(8)+Vic(9)

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Theinstrumentcorrectionisdeterminedfromaninstrumentcalibrationbeforeorduringthepitot-staticleakcheck.Note:someinstrumentationsystemsprovideVicdatadirectlynegatingStep2.

Step3

CalculatecalibratedairspeedofthecalibratedsystemforeachtestpointasfollowsandenterintheVcalcolumn(7):

Vcal(7)=Vic(5)+Vpc(6)

Step4

CalculatepositionerrorforthesystemundertestforeachtestpointasfollowsandenterinVpccolumn(11):

Vpc(11)=Vcal(7)-Vic(10)

Step5

Oncethepositionerrorhasbeenevaluatedforeachdatapointofthesystemundertest,thetrendlinescanbedeterminedandanequationforthetrendlinescanbecalculatedforfutureuse.FortheexampledatafigureE-1,theequationsare:

Vpc=11.44348-0.11145*Vic+0.0000965026*Vic2(ExampleOnly)Vcal=12.13316+0.871*Vic+0.00017927*Vic2(ExampleOnly)

Step6

Calculatethepressuredifferencebetweenthesystemcalibratedairspeedandthesysteminstrumentcorrectedairspeed.Theequationsareasfollows:

qc=Passl*(((-1)/2*(Vcal/assl)2+1.0)(/(-1))1)qci=Passl*(((-1)/2*(Vic/assl)2+1.0)(/(-1))1)P=qc-qci

Where:qc=calibratedimpactpressure(in.-Hg)qci=instrumentcorrectedimpactpressure(in.-Hg)Passl=ambientpressurestandarddaysealevel=29.92125in.-Hg=1.4assl=speedofsoundstandarddaysealevel=661.4786ktP=pressuredifference(in.-Hg)

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Step7

Calculatethecalibratedpressurealtitude.Theequationisasfollows:

Exp=R*hssl*gc/gsslHpcal=Tssl/hssl*(1.0-((PaP)/Passl)Exp)

Where:Exp=exponentR=engineeringgasconstant=96.0340ft-lbf/lbm-Khssl=standarddaytemperaturelapserate=0.0019812K/ftgc=gravitationalconstant(lbm/slug)~32.17(lbm/slug)gssl=gravitationalconstantstandarddaysealevel=32.17(lbm/slug)Hpcal=calibratedpressurealtitude(ft)Tssl=airtemperaturestandarddaysealevel=288.15KPs=instrumentcorrectedstaticpressure(in.-Hg)P=pressuredifference(in.-Hg)Passl=ambientpressurestandarddaysealevel=29.92125in.-Hg

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VCAL=+IND+IND=PositionError(kt)CallibratedAirspeed(kt)LineofZeroErrorTOP7-3-05710April2008

APPENDIXE.EXAMPLEDATAPRESENTATION.

FigureE-1ShipAirspeedCalibrationUH-60USAS/NXX-XXXXX

Avg

AvgCG

Avg

Avg

Avg

Symbol

Gross

Location

Density

OAT

Rotor

Calibration

Weight

Altitude

Speed

Method

(lb)

(FS)

(ft)

(degC)

(%)

16,80020,470

352.2350.7

6,9008,970

12.09.0

100100

TrailingDevicePace

Notes:1.Configuration:Clean,DoorsClosed,WindowsClosed,ALQ-144Removed2.Condition:LevelFlight;BallCentered10

5

0

-5

140

130

120

110

100

90

80

70

60

50

40

3030405060708090100110120130140InstrumentCorrectedAirspeed(kt)E-1

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APPENDIXF.GLOSSARY.

hsslstandarddaytemperaturelapserateasslspeedofsoundstandarddaysealevelAvgaverage

CGcenterofgravity

EvteventExpexponent

FSfuselagestationFTMflighttestmanual

gcgravitationalconstantgsslgravitationalconstantstandarddaysealevel

Hpcalcalibratedpressurealtitude

IAWinaccordancewith

MIL-STDmilitarystandard

OAToutsideairtemperature

PsinstrumentcorrectedstaticpressurePasslambientpressurestandarddaysealevelPtpointPpressuredifference

qccalibrateddynamicpressureqciinstrumentcorrecteddynamicpressure

Rengineeringgasconstant

TDtestdirectorTOPTestOperationsProceduresTsslairtemperaturestandarddaysealevel

VindindicatedairspeedVicinstrumentcorrectedairspeedVcalcalibratedairspeedVpcpositioncorrectionairspeeddelta

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APPENDIXG.REFERENCES.

1.FederalRegulation,FAR,FederalAviationRegulation,20August2007.

2.MilitaryStandard,MIL-STD-882D,DepartmentofDefense,StandardPracticeforSystemSafety,10February2000.

3.FlightTestManual,USNTPS-FTM-No.106,RotaryWingPerformance,USNTPS,NAWC,31December1995.

4.Report,USStandardAtmosphere,preparedundersponsorshipoftheNationalAeronauticsandSpaceAdministration,UnitedStatesAirForce,andtheUnitedStatesWeatherBureau,1962.

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Comments,recommendedchangesoranypertinentdatawhichmaybeofuseinimprovingthispublicationshouldbeforwardedtothefollowingaddress:TestBusinessManagementDivision(TEDT-TMB),USArmyDevelopmentalTestCommand,314LongsCornerRoad,AberdeenProvingGround,MD21005-5055.Phone(410)278-1486,DSN298-1486.Technicalinformationmaybeobtainedfromthepreparingactivity:FlightTestDirectorate(TEDT-AC-FT)USArmyAviationTechnicalTestCenter,Building30137,CairnsArmyAirfield,FortRucker,AL36362-5276.Phone:(334)255-8149,DSN:558-8149.AdditionalcopiesareavailablefromtheDefenseTechnicalInformationCenter,8725JohnJ.KingmanRoad,STE0944,FortBelvoir,VA22060-6218.Thisdocumentisidentifiedbytheaccessionnumber(ADNo.)printedonthefirstpage.