NASA Technical Memorandum 84549

ACEE PROGRAM RATIONALE AND IMPLEMENTATION

NASA-TM-84549 19850002600

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WILLIAM S. AIKEN) JR,) AND RICHARD H. PETERSEN

AUGUST 1982

NI\S/\National Aeronautics andSpace Administration

Langley Research centerHampton. Virginia 23665

LIBRARY COpyOCT D 1982

.LANGLEY RESEARCH CENTEFtLIBRARY, NASA .

Jit..11etOtlL VIRGflll;S

https://ntrs.nasa.gov/search.jsp?R=19850002600 2019-02-15T19:58:56+00:00Z

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1

INTRODUCTION

NASA'sAircraftEnergyEfficiency(ACEE)Programwas

begunin 1076followingayearofplanning.Thispaper

verybrieflyreviewstherationalefor this intensiveNASA

effort,butlooksattheissuesbehindtheACEEProgram,

aswellasits implementation,fromtheperspective

availablein 1981.

THEAIRCRAFTENERGYEFFICIENCYPROGRAM --

2

A principalreasonforconcernforair transportfuelefficiency,ofcourse,is everybody'scriticaldependencetodayonair transportation.

In the UnitedStates,our dependenceonair travelincreasedsubstantiallyoverthe pastfiveyearsandair transportnowaccountsforten timesasmanydomesticpassengermilesasits nearestpublictransportationrival--thebussystem.

Butin 1980airlinepassengermilesdeclinedsharply.

2

WE HAVE BECOMEDEPENDENT ON AIR TRAVEL

81822/82

BUS", RAIL"-

- -------------------------------------::::~~~-=.-=-'7-=:--.:.:.: -----------.-0_. _,, ._.__ ----_._-_.---._ .. _._._-- ._----

240

220

200

180

160

DOMESTIC 140

PASSENGER120MILES

( BILLIONS) 100

80

60

40

YEAR

Thereasonbehindthisdeclinewasthe largeincreaseinairlines'operatingcostsandticketpricesthataccompaniedtherisein fuelcoststothedollar-per-gallonleveltheyearbefore.Thecurrentdominantinfluenceof fuelcostondirectoperatingcostisclearlyillustratedbythisfigure.Fuelis nowabout60_oofthetotalandstillclimbing.

3

B3A12181

• ELEMENTSOF AIRLINE DIRECTOPERATING COST

2.00- FUELn

1.80-m

1.60-

1.40-IJ.l._I

"_ 1.20-

_u__1.00-_u_O.80m-- ,,,/_//.,,.._.7z - ,CREWIJ.l

0.60- MAINTENANCE- (Directand

0.40- Indirect)

- /_,,,,OTHER0.20-

0 I I I I i I I I I I I I1970 1972 1974 1976 1978 1980

CALENDARYEAR

Another, perhapsevenmorecritical, issueis our airtransport industry's increasinglyimportantimpactonthe balanceof U.S. trade, It has longbeenthe leadingindustrial contributorof positivetradebalancestopartiallyoffsetour importof autos,oil andother productsand, in 1980,produceda 6-billion-dollarsurplus.

5

Until1977our industryconsistentlycapturedabout95percentoftheworldmarket.Butthecompetitionfromabroadis nowcomingonstrong. Ontheaverage,overthethreeandone-halfyearsendingin mid-1981,Airbus Industriescapturedover20percentoftotaltrans-portsalesandfirmlytookoversecondplacebehindBoeing.Thesegainsreflectenlightenedandsub-stantialhelpfromtheEuropeangovernmentsinvolved.

5

BIBll9181

THEAIRBUSHASIMPACTEDU.S.SALESIO0

,... 0 BOEING,DOUGLAS,LOCKHEED .....G AIRBUS

I

I

I

75 --II

PERCENTOFTOTALSALES

UNITS 50ORDERED

29

, 2.5 20

•_. • II 13• .._.:.,2,;..

.'.':'-.'2."

.to'." .'.°

1971-1977 1978 1979 1980 1981(TO7111

Andtheworstnewsofall istheoutlookfor futurefuel costs.Theseareforecasts,compiledbytheAirTransportAssociation,thatprojectthree-dollar-per-gallonfuelbythe endofthis decade.Clearly,if wewanttobothkeepour airlineshealthyandkeepadominantshareoftheair transportmarket,wemustproducefuel-efficienttransportaircraft.

J |p i

6

........... - ...... FUEL PRICE FORECAST............B3.......5/81

• l* CURRENTJFORECASTS

¢00 • P&WA--BOEING (SPREAD)

3.50 a IWA

z , McDONNELLDOUGLAS /AVERAGE....,°'3.00 * LOCKHEED

"_o_2.50 _yu-,2.00

ACTUAL ..-o 1.50 /r'_ //e_tt//

1.00INTERNATIONAL[_./,

0.50,,_---_-------.____,__, _._j j . j "DOMESTICu" ' . i , , , l l58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90

YEAR

7

Thus,whenonelooksbacksix yearsto theformulationof theACEEProgrambya NASATaskForceanda numberofsupportinggroups,the Program'srationale,as it wasstatedinthis early1976viewgraph,still appearsvalid.

7

B1A.EVOLUTIONOF THE AIRCRAFT ENERGYEFFICIENCY 2/76

(ACEE) PROGRAM

MOSS/GOLDWATERREQUESTFORAIRCRAFTFUELCONSERVATION NASATASKTECHNOLOGYPLAN(JAN.1975) (WITHFAA,DOD)

PRELIMINARYAFCTPLANS. REVIEWSBY GOVT./INDUSTRY

GROUPS, JSENATECOMMITTEEHEARING

NASAFORMULATIONTO: PRESERVEU.S. INDUSTRY'S

OFACEEPROGRAM COMPETITIVEADVANTAGEIN WORLDTRANSPORTAIRCRAFTMARKETSTHROUGHTECHNOLOGYFORFUELEFFICIENCY

8

Thecontentandtiming of the initially approvedACEEProgramis shownhere. Thereweresixseparateeffortsstartedandall but onewereplannedwith future phasesthat wereto bedependenton theoutcomeofthe earlier efforts.Thus, the programplanwasinherently dynamicandchangeswereindeedmadeasthe precedingeffortandexternaleventsdictated.

ACEEINITIALLY APPROVED PROGRAM

804022J82

ENGINECOMPONENT

IMPROVEMENT

ENERGYEFFICIENT

ENGINE

ADVANCEDTURBOPROPS

ENERGYEFFICIENT

TRANSPORT

LAMINARFLOW

CONTROL

COMPOSITEPRIMARYAIRCRAFT

STRUCTURES

BIll AERO. ACTIVE CONTROL.

_CONCEPTS [VAL. FLIGHT CONTROL •

• CONCEPTS EVALUATIONS.

IIYSTEM DESIGN. TEST.

• VALIDATOR A1c MODIFICATION. FLiGHTTEST_

9

Theactualtiming andfundingofall ofthe six separateprogramsnowcomprisingthe ACEEeffort is shownhere. Thedollartotalson the rightincludebudgetsfor the nextfour yearsin termsof FY-81dollars. Theprogramtotal is almosta half-billion dollarsevenwithout majoradd-ons.

Thetopthree programsaretheengineprogramsbeingimplementedbyNASA'sLewisResearchCenter. TheEngineComponentImprovementprogramis essentiallycomplete,havingdevelopedselectedimprovedcomponentsin current enginedesignsand,with diagnostictesting,identifiedcausesofshort andlongterm engineperformancedeterior-ation. TheEnergyEfficientEngineProgramis alsonearingcompletionwith just onefundingyear left. Here,twonewdesignsarebeingtakento groundtestsofprototypeengines. TheAdvancedTurbopropProgramis just beginningits secondphasewhich includesgroundtestof largescaleprop-fanstructures.

Thefirst of threeACEEairframeprogramsis the EnergyEfficiencyTransport(EEl)Programthat embodiesselectedadvancesin activecontrolsandaerodynamicsandis nearlycomplete.Thesecondairframeeffort is the CompositePrimaryAircraft Structures (CPAS)Program,wheresecondarystructuresdevelopmentandwingstudiesarecomplete,mediumprimarystructuresdevelopmentis nearlycomplete,anda"largestructureskeytechnologyeffort" is just beginning. Andthefinal ACEEeffort,well into its subsystem- developmentphase,isdemonstrationof the commercialviability of LaminarFlowControl.

AIRCRAFT ENERGY EFFICIENCY PROGRAM

904019181

1976 7T 19n 1978

ASCAL YEAR

1979 1980 1981 1982 1983 1984 1985

BUDGETTOTALS(FY 81$)

ENERGYEFFICIENT

ENGINE$2lIIM

TURBOPROPS $4OM

ENERGYEFACIENT

TRANSPORT

$78M

LAMINARFLOW

CONTROLS47M

10

Someof the selectedadvancesin activecontrolsandwingaerodynamicsthatarepartof theEnergyEfficientTransportprogramareindicatedhere.Earlyeffortsin this programledto introductionoverayearagoof anactivesystemformaneuverandgust-loadcontrolon the L-I011-500topermitag-footwingspanextension.In operation,this combinationhasso-farconsistentlyproducedmorethanthe expectedthreepercentfuel savings.ThemoreFecentEETactivecontrolseffortshavebeendirectedtowardrelaxedstaticstability.Th.eEEl"aerodynamicseffortshavefilledcriticalgapsin NASAwindtunnel researchonhigh-aspect-ratiosuper-criticalwingconfigurationsandtakenwingletdevelopmentbeyondthewindtunnel.

EET

ADVANCED TECHNOLOGY FEATURES HIC

HIGH ASPECT RATIO LOW SWEEP, WINGLETS 1/80SUPERCRITICAL WING

it

/i

I

PROPULSION/AIR FRAM E //

INTEGRATION /'

f ./"-7. RELAXED: ' STATIC

STABILITY

DIGITAL AVIONICS i /

i '

"\

ADVANCED LONG DUCTDESIGN NACELLE MANEUVER/GUSTCONVENTIONAL , LOADS CONTROLDESIGN HIGH LIFT \

DEVICES

11

In fact, theEElprogramfundedflighttestsofwingletsontheAir Force'sKC-135indicatingpotentialfuelsavingsof70/o.

KC-135 WINGLET FLIGHT DEMONSTRATION

12

AndEETflight testsofwingletsonthe DouglasDC-IOshowadesirablefuel savingsbenefitpotentialon this aircraft, butalsothe needforsomedesignchanges.

-

13

TheACEECPASeffortonsecondarystructureshasinvolveddevelopmentof selectedcompositecontrolsurfaces--theupperaft rudderon Dou{jlasDC-10,inboardaileronsfor the LockheedL-1011,andelevatorsfor Boeing's727.Thesesecondarystruc-tureseffortsnowinvolveonlyflight servicefor maintenanceevaluationandhavealreadyspurredcommitmentof thecontrolsurfaceson twonewtransportsto,all-compositeconstruction.

TheCPASProgram'sdevelopmentof "mediumprimary"tail-surfacestructuresincludesdevelopmenLofcompositeverticalstabilizersfor theDouglasDC-10andLockheedL-1011andacompositehorizontalstabilizerfor Boeing's737.A numberofthesestructureshavebeenfabricatedandfull-scaletestsarewellunderway.Whilethiseffortappearstohavepreparedtheindustrytousecompositesin correspondingnew-airplanestructure,preparationforwingandfuselageapplicationshasbarelybegunwithsmallCPAScontractstocloseselectedkeydesign-technologygaps.TheCPASProgramplanincludesaproposedcomposite-wing-structuredevelopmentphase,

•beginningin 1983.

ACEE COMPOSITECOMPONENTS_ FI_6/78

SECONDARYSTRUCTURES PRIMARYSTRUCTURES! | i

DC-10RUDDER

L-1011

L-1011 VERT!CALFIN

HORIZONTALTAIL

727

DC-10VERTICALFIN

14

Finally,theACEELaminarFlowControl(LFC)Programnowinvolvesmajorwindtunnelandflight teststoevaluatepotentiallypracticalsystemsfor maintainingthe surface"boundarylayer"ofair overthewingsina smooth,laminarstatethroughsuction.Thisprogramincludesaplannedthird, integrated-systern-flight-testphasetodemonstratereadinessof this technologyfor industryexploitation.

14

WHATISLAMINARFLOWCONTROL? _,, 5/80

• .... NORMALSURFACELAYER ............ "

THICKANDTURBULENTWITH-HIGHDRAG

SUCTION-STABILIZEDSURFACELAYER

THINANDLAMINARWITHLOWDRAG

BENEFIT:MINIMUM20%FUELSAVINGOVERFUTURETURBULENTTRANSPORTS

15

Thecurrentoutlookforbenefitsandtechnologyreadinessof thethreeACEEEngineProgramsisshownhere.Enginecomponentimprovements,developedin theEClprogramarealreadybeingincorporatedinlDnewproductioncopiesofthreecurrentenginedesignsandtheprojected5%fuel-savingsbenefitwill apparentlybeachieved.EnergyEfficientEnginetechnologyreadinessfordevelopmentis projectedatabout1984with expectedfuel savingsin the15-20percentrange.AdvancedTurboproptechnologyreadinessis expect-edlatethisdecadewithprojectedfuel savingsovercurrenttransportsnowin the30'-40percentrange.Achievingthisis dependenton NASAimplementationof athirddemon-strationphaseof thisproject

i=

• j J i

15

E1A

ACEEPROPULSIONPROJECTS 1/8oPROJECTEDFUELSAVINGS& TECHNOLOGYREADINESSDATES

40m

•MEORANGEMISSION . ADVANCED• SAVINGSRELATIVE TURBOPROP

30-- TOCURRENT (ATP)ENGINES

FUEL

SAVINGS,20-- _ EI_ERGYEFFICIENTENGINE% _ (E_')

10n

(__ ENGINECOMPONENTIMPROVEMENT(EC])

o ' I I I1980 1985 1990 1995

TECHNOLOGYREADINESSDATE

16

Thecurrentoutlookfor benefitpotentialfromACEEairframetechnologiesis summarizedhere. TheEETandCPASprogramshavealreadyassuredapplicationsof activewing loadalleviationandcompositesecondarystructure for aboutfivepercentfuelsavingspotential.Bythe endof this decade,it appearstheindustrywill bereadywith advancedsupercriticalwings,winglets,activestabilityaugmentation,andcompositeprimarystructure, includingwingstructure if theCPASplanisimplemented,for totalsavingsin the20percentrange.Andbythe late1090's,LaminarFlowControlreadinesswill bringwith it fuel savingspotentialovercurrent aircraftof 40percentor more.

"i

o

16ACEEAIRFRAMETECHNOLOGIES 2/82

PROJECTEDFUELSAVINGSTECHNOLOGYREADINESSDATE

LAMINARFLOWCONTROL40 - • SAVINGSRELATIVETO i

CURRENTAIRCRAR"

30-

FUELSAVINGS, SUPERCRITICALWING]WlNGLETS

% ACTIVESTABILITY

AUGMENTATION20- COMPOS_PRIMARYSTRUCTURE

10- _2__ .__ ACTIVEw_Nr,LOADALLEWAT_ONS COMPOSITESECONDARYSTRUCTURE

0 I I I I I1980 1985 1990 1995 2000

TECHNOLOGYREADINESSDATES

17

CONCLUDINGREMARKS

It mustbeemphasizedthatthebenefitpotentialsandtechnologyreadinessdatesprojeotedheredependoncompletionoftheongoingandplannedACEEeffortsonschedule.TherealizationoffuelsavingbenefitsfromACEEProgramtechnologiesdependsalsoontherateandmannerinwhichtheycanbeimplementedbytheairtransportindustryaftertechnologyreadinessisachieved.Theirimplementationwillclearlybeasrapidastheindustry'smarketopportunitiesandeconomicswillallow.Thebenefitfromtheircombinedimplementationona singlenewaircraftwouldnotbethesumofthebenefitpotentialscitedabovebutcouldeasilyexceedthe50%potentialthatwascitedwhentheACEEProgramwasinitiated.

•1. Report No. 2. GovernmentAccessionNo. 3. Recipient'sCatalogNo.

NASATM-84549"4. Title and Subtitle 5. Report Date

ACEEPROGRAMRATIONALEANDIMPLEMENTATION August 19826. PerformingOrganizationCode

534-01-13-067. Author(s} 8. Performing Organization Report No.

• William S. Aiken, Jr., and Richard H. Petersen10. Work Unit No.

9. PerformingOrganizationName andAddress

NASA LangleyResearchCenter '11.Contract or Grant No.

Hampton,VA 2366513. Type of Report' and PeriodCovered

12. SponsoringAgency Name and Address Technical MemorandumNationalAeronauticsand SpaceAdministration 14.SponsoringAgency Code'Washington,DC 20546

15. SupplementaryNotes• Director, Aeronautical SystemsDivision, NASAOffice of Aeronautics and SpaceTechnol(gy• *Deputy Director, NASALangley ResearchCenterPresentedat theACEEProjectOral StatusReviews,DrydenFlightResearchCenter,Edwards_Cal!.fornia_September14_ 1981 ..

16. Abstract

It must be emphasizedthatthe benefitpotentialsand technologyreadinessdatesprojectedheredependon completionof theongoingand plannedACEEeffortsonschedule.The realizationof fuelsavingbenefitsfromACEE Programtechnologiesdependsalsoon the rateand mannerin whichtheycan be implementedby the airtransportindustryaftertechnologyreadinessis achieved.Theirimplementationw_ll clearlybeas rapidas the industry'smarketopportunitiesand economicswillallo_.The benefitfromtheircombinedimplementationon a singlenew aircraftwouldnotbe the sum of the benefitpotentialscitedabovebut couldeasilyexceedthe 50%potentialthatwas citedwhen the_ACEEProgramwas initiated.

i7. Key Words (Suggested by Authoris)) 18. Distribution Statement '

AircraftFuelEfficiency,Composites,Active Controls, Supercritical Wings, FC_DI__Winglets, Laminar Flow Control

Subject Category Ol

19. Security Qa=if. (of thisreport) 20. SecurityCla_if. (of this _ge) 21. No. of Pages 22. Dice

Unclassified Unclassified 34

Available:NASA'sIndustrialApplicationsCenters

3 1176 00021 0121l '