s .’} SECURITY INFORMATION?

-J RESEARCHMEMORANDUM-

CONTROLCHARACTERISTICSOF TRAILING-EDGESPOILERSON

UNTAPEREDBLUNTTRAILING-EDGEWINGSOF ASPECT

RATIO 2.7 WITH0° AND45° SWEEPBACKAT

MACHNUMBERSOF 1.41 AND 1.96

By Carl R. Jacobsen

LangleyAeronautical Laboratory

&‘Langley Field, Va.

.s

mumarto&&rd ‘Per=n!sImOMt&dkglaw. ‘

NATIONALADVISORY COMMITTEEFOR AERONAUTICS

* WASHINGTON

3(% 7//;7*.t December 3, 1952#w

! AWEU#WML. ..

1s NACAw L52J28

. NATIONALADVISORYCOMMITTEEFOR

RESEARCHMEMORANDUM.

TECHLIBRARYKAFB,NM -+—

Illlllllllllllllllllll!l!lll“--Olywi “-—AERONAUTICS

CONTROLCHARACTERISTICSOFTRA~G-EME SPOILERSON

, UN’JMPEREDBLUNTTRAILING-EIX3EWINGSOFASPECT

RATIO2.7WJZ’H00-AND47 SWEEPEACKAT

MACHNUMBERSOF 1.41AND1.96

By CarlR.Jacobsen

SUMMARY

An investigateionhasbeenmadeintheLangley9- by 12-tichsuper-sonicblowdowntunneltodeterminethecontrolcharacteristicsof full-spantrailing-edge.spoilersontworelatedfull-blmrtwings(trailing-

. edgethicknessequaltomaximumwingthickness)ofaspectratio2.7with0°and450sweepbackatMachnumbersof 1.41and1.96. A wingsimilarhplanformto theunsweptwhg, butlargerandhavinga partiallyblunt.trailingedge,wasalsotestedwitha pivotedfull-spantrailing-edgespoilerwhichbecamedetachedfromthesurfaceofthewingat thehigherprojections.Alsoincludedaretheresultsobtainedfora spoilerlocatedatthe70-percent-chordlineof thetwofull-bluntwings.TheresultswereobtainedatReynoldsniunbersrangingfrom1.3 x 106to2.3X 106.

Theresultsof theinvestigationshowedthatthetrailing-edgespoilercausedlargerchangesinlift,rollingmoment,andpitchingmomentthanthespoilerlocatedat the70-percent-chordHne. Theeffectoftheverticalgapbetweenthepivotedspoilerandthesurfaceofthewingatthetrailingedgewasto reducesharplytherateofchange.oftheMft incre~ntandrolMngmomentwithfurtherprojection.Fromlateral-controlconsiderations(rollingmoment,wingtwistingmoment,andprobablehingemoment),thetrailing-edgespoilerontheunsweptpartiallybluntwingcomparedfavorablywitha 25-percent-chordtrailing-edgeflap.

INTRODUCTION

Previousexperimentalinvestigationsat supersonicspeedshaveshowntherolling-momenteffectivenessof spoilerstobe comparabletotherolling-momenteffectivenessof flap-typecontrols(refs.1 and2).

* Spoilers,therefore,,a~earpromisingsincetheymightalsobe expectedto causelesswingtwistingmoment(ref.2) andhavelowerhingemoments

*

(ref. 3) thanflap-typecontrob.Reference”-lhasshoynspoilereffec-tivenessto increasewithrearwardchordwisemovementofthe-spoiler,indicatingthatthemaximumeffectivenessmightoccuratthetrailingedge.Forstructuralreasons,trailtig-edgespoilersappearpracticalforuseonlyonblunttrailing-edgewings.Theresultsofreferences4and5 tidicatethata partiallyblunttrailing-edgewingmightbe usedatMachnumbersoftheorderof 1.0or2.0withlittlepenaltyinthewingaerodynamiccharacteristics.CalcuhtionshavefurtherindicatedthatathigherMachnumbersthewingtrailingedgemaybe thickenedconsiderablywithlittleorno increaseindrag.

In ordertaobtaininformationconcerningthecontrolcharacter-isticsof spoilersonwingswithfull-blunttrailingedgesat super-sonicspeeds,taninvestigationhasbeenmadeof spoilerslocatedat thetrailingedgeoftwountaperedwingsof aspectratio2.7with0° and450sweepback.Becausethesefull-bluntwingswereexpectedtohaveexcessivedragatthetestMachnumbers,a trailing-edgespoilerwasalsotestedona winghavingthesameplanformasthe.unsweptwinganda ratiooftrailing-edgethicknesstomaximumthickessofone-third.Thespoileronthispartiallybluntwingwaspivotedaboutthe85-percent-chordstationandbecamedetachedfromthesurfaceofthewingatpro-jectionsabove2.4percentofthechord,thusallowingairflowbetweenthespoilerandthewing.Forcomparisonpurposes,datawerealsoobtainedforthetwofull-blmtwingswithspoilerslocatedatthe70-percent.chordline. —

TheinvestigationwasmadeatMachnumbersof 1.41and1.96 andatReynoldsnumibersrangingfrom1.3X 106to2.3X 106. Datawereobtainedwhichwereapplicabletopositiveandnegativespoilerprojec-tionsatanglesofattackupto25°.

CL

CD

cm

COEFFICIENTSANDSYMBOLS -—

liftcoefficient,Lift/qs

tiagcoefficient,Drag/qS

pitching-momentcoefficient,

Pitchingmomentakmut0.255qs;

.—

.

.

—

.-

.

...

----

NACARM L52J28

czgroBB

cl

cngross

3

grossrolling-momentcoefficient,-

Rollingmomentofthesemispanmodel2qSb

rolling-momentcoefficientdueto controlprojection,%ross - (C,*O.J;=O

grossyawing-momentcoefficient,

Yawingmomentof thesemispanmodel2qSb

yawing-momentcoefficientduecngross- (cngo..)g=o

incrementsinlift,drag,andcoefficientsdueto spoiler

basepressurecoefficient

free-streamdynamicpressure,

semispanwingarea,sq in.

wingchord,in.

meanaerodynamicchord,in.

wingspan,twicedistantfromtowingtip,in.

to controlprojection,

pitching-momentpro~ection

lb/sqIn.

wingrootchord

spoilerprojectionmeasuredfromwingsurfaceinaplanenormalto chordline,positivewhenlocatedonuppersurface,in.

angleofattack,deg

Reynoldsnumberbasedon &

--nAQImmmIA& NACARM L52J28

MODEIS ..–P-

Thethreesemispan-wingmodelsof solidsteelwhichweretested(designatedA, B, andC andseeninfigs.1 and2)haduntaperedplanformswithaspectratiosof2.7andsymmetrical,6-percent-thick,flat-sidedsectionswithleading-edgewedgeswhich-extended-tothekO-percent-chordstation.WingA wasunsweptandhada full-blunttrailingedge(fig.1). WingB wassweptback4.50but,otherwise,wasidenticaltowingA. Thespoilerslocatedatthetrailtigedgeandat the~-percent-chordlineofwingsA andB extendedfromthewing-fuselageintersec-tionat0.16~/2tothewingtip. Control”projectIons“weresimulatedby progressivelymachiningthe0.028-inch-thickbrassspoilersfromaninitialprojectionof6 percentofthechord.downtoeachdesiredheight.Pressureorificestomeasurethebasepress~eofwingA werelocatedat23,47,71>and95percentoftheexposedsemispan.

.

WingC (figs.2 and3)wassimilartowingA butwaslargerandhadthetrailingedgebeveledtoa 2-percent-chordthiclmess.Thetrailing- .—

edgespoilerforwingC pivotedextendedfromthewing-fuselage

aboutthe85-percent-chordstationandjunctureat 0.llb/2tothewingtip. 6

TUNNEL J... — ●---

TheLangley9- by 12-inchsupersonicblowdowntunnel.inwhichthepresenttestsweremadeutilizesthecompressedairoftheLangley19-footpressuretunnel.Theairentersatanabsolutepressureof

about2~ atmospheres.3 To insure condensation-freeflow,theairis

passedthrougha silica-geldryer,andthenthroughbanksoffinnedelectricalheaters.Thecriteriafortheamountofdryingandheating

—

necessaryforcondensation-freeflowwereobtainedfronireference6. .

ThetwotestsectionMachnumbersareprovidedby interchangeablenozzleblocks.Thefree-streamMachnumbershavebeencalibratedat 1.41t 0.02~d 1.96 * 0.02. Thecorrespondingstatic-pressurevariationswereaboutt2.Opercentat .M= 1.41 andi2.2percentat M = 1.96. ThedeviationinstreamangleforthetunnelclearconditionwasiO.250at M = 1.4.1andti.20°at M = 1.96. Theresultsofthetunnelcalibrationtests(ref.7)wereusedindeterminingthedynamicpressureswhichwereused .__.._inreducingthedata. —

TheaveragedynamicpressureandReynoldsnumberateachMachnumberforthethreemodelsareasfollows:

NACARM LZJ28 5

Mach Reynoldsnumberfor-number (lb/s:in.)

WingsA andB wingc

1.41 12.o 1.6X 106 2.3 x 106~.96 10.5 1.3 1.9

ThetestReynoldsnunberdecreasedabout2 percentduringthecourseofeachrunbecauseof thedecreasingpressureoftheinletair.

TESTTECHNIQUE

Thesemispanmodelsusedinthisinvestigationwerecantileveredfroma strain-gagebalancewhichmountsflushwiththetunnelwallandrotateswiththemodelthroughtheangle-of-attackrange.A testbodywasattachedtoeachof thewingsandloadsweremeasuredonthewing-bodycombinations.Thetestbodyconsistedofa half-bodyofrevolutionanda 0.25-inchshimwhichwasusedtoraisethehalf-tidyofrevolutionoffthetumnelwallandthusminimizetheeffects.ofthetunnel-wallboundarylayerontheflowoveritssurface(ref.8). Becauseof thebalancedeflectionunderload,a gapofabout0.010inchwasmaintainedbetweenthetestbodyandthetunnelwallundera no-loadcondition.Therolling-andyawing-nmmentaxeswerelocatedat theelectricalcenterof thebalance(seefigs.1 and2).

Allthreewingmodelswereoriginallytestedbothwithandwithouttransitionstrips.Becauseoftestdifficulties,theonlyfinaldataobtainedwerethosewithouttransitionstripsforthefull-bluntwings,A andB, andthosewithtransitionstripsforw~ C. The transition-fixeddataforwingC wereobtainedwitha 0.033cbandof Carborundumgrainshavingmaximumdimensionsof about0.004inchwiththeforwardedgeof thebandlocated0.065cbehindthewingleadingedge.Theinvestigationwasmadeat anglesofattackwhichvariedfrom-26°to2’j0andat spoilerprojectionswhichvariedfromO to 10percentof thewingchord.Completedataforallwingandsmilerconfi ations,however,wereobtainedonlyat anglesofattackfrom-@ to8%nd at spoilerprojectionsfromO-to6 percentof thewingchord.Theangle-of-attackrangeat.M = 1.41 wasnecessarilymorelimitedthanat M . 1.96becauseoftunnelblockageandshock-interferenceeffects. 1

6 NACARM L52J28

ACCURACY

No tarecorrectionshavebeenappliedtoanyofthedatapresented.Froma generalconsiderationofbalance-calibrationaccuracyandrepeata-bilityof data,theaccuracyof themeasurementofforcesandmoments,intermsof coefficients,arebelievedtobe aboutas follows:

CL . . . . . . . . . . . . . . . . . . . . . . . . r. . . . . to.go5c1 . . . . . . . . . . . .*. . . . . . . . . . . . , . . . . ~ocoolCD . . . . . . . . . . . . . . . . . . . .. . ,..~... . . ● to.oolcm . . . . . . . . . . . . . . . . . . . . . . .*.* , . . .

—io.oo2

Cn . . . . . . . . . . . . . . . . . . . ● . . . . . ● ., . .io.0002

Theangle-of-attackvaluesarebelievedtobe accurat6withiniO.0~,baseduponthelimitationsofthemechanicalangle-of-attacksystemandthecalibrationchartsfromwhichtheactualvalueswereobtained.

RESUE1’SANDDISCUSSION —h

Variationsofthelift,rolling-moment,andpitching-momentcoeffi-cientsofthesemispanmodelswithprojectionof spoilers locatedatthetrailingedgeofthethreewingsarepresentedinfiguresk to 6 forvariousanglesofattack.Theseforceandmomentmeasurementsarepre-sentedprimarilyto showsamplesofthebasicdataas.themeasurementsincludeloadsona somewhatarbitrarytestbodyandare,therefore,notdirectlyapplicabletoconfigurationsincludtigmoreconventionalbodyarrangements.It isbelieved,however,thattheuseofa differentbodyarrangementwouldnotqualitativelyaffectthedata.Therangeoftestvariablesforthetwowings,A a~dB, withthe70-percent-chord-stationspoilers(notpresented)wasessentiallythesameasthatforthetrailing-edgespoilers.BasepressuremeasurementsobtainedalongthetrailingedgeofwingA (unsweptfull-bluntwing)bothwithandwithouta 6-percent-chord-heightspoilerarepresentedinfigure7.

Becausethemodelsaresymmetricalthedataobtainedinthenegativeangle-of-attackrangewerealsoapplicabletonegativespoilerprojec-tionsatpositiveanglesofattack.Thedatacontainedinfigures4 to7 are,therefore,presentedatrepresentativepositiveanglesofattackinfigures8.and9..Comparableforcedataforthespoilerlocatedatthe~-percent-chordlineof thetwofull-bluntwings,A andB, alongwithcompleteincremental-dragandyawing-momentdataarealsoincludedinthesefigures.Forthefewverylimitedcasesinwhichdatawereobtainedforthewingsbothwithandwithouttransitionstrips,thedataindicatedthattheattempttofixthetransitionhadlittleeffecton theincrementalloadscausedby theprojectedspoil-er.Thetrailing-edgespoiler-base-dragand~- W3WiW&@ncrementsdueto spoiler

--

.

..-

NACARM L52J28 7“

.projectionobtainedon theunsweptfull-bluntwingby integrationofthebasepressurescontainedinfigure7 areincludedwiththedragdatainfigure8.

UnsweptWings

Liftandrollingmoment.-Allspoilersonthetwounsweptwingsproducedsubstantialliftincrements(fig.8(a))androllingmoments(fig.8(b))throughouttheangle~of-attackrange.Usuallytheliftincrementsandrollingmomentsdecreasedforupper-surfaceprojectionsandincreasedforlower-surfaceprojectionsastheangleofattackwasincreased,thusindicatinglittlechangeintheliftincrementandtherollingmomentfordifferentiallyprojectedspoilerswithincreasingangleof attack.Theliftincrementsandrolling-~menteffectivenessofthepivotedspoileron thepartiallyblmt wingat M = 1.41 wereslightlylessthemthoseof thetrailing-edgespoileron thefull-bluntwingforprojectionsbelowthatatwhicha verticalgapoccurredbetweenthepivotedspoilerandthesurfaceof thewing(~= tO.024).At angles

=, ofattackof4°,8°,and14°,andat M= 1.96,theliftincrementsandrolling-momenteffectivenessof thepivotedspoileronthepartiallybluntwingwereessentiallythesameas thoseofthetrailing-edgespoileronthefull-bluntwingatprojectionsbelowthatforwhichtheverticalgapoccurred.Beyondthisprojectionthesevaluesweresub- “stantialdylessthanwhattheywereforthetrailing-edgespoileronthefull-bluntwtig. Thespoileron thepartiallybluntwingwaspro-jectedup to 10percent,buttherewaspracticallyno differencebetweentheliftincrementsandrollingnmmentsat 6 and10percentprojection(seefig.6). Consequently,thedatafrom6 to 10percentprojectionwereomittedfromthesefigures.

Forequalspoilerprojectionson thefull-bluntwtigs,thetrailing-edgespoilerinmostcaseshadabouttwicetheeffecton liftincrementandrollingmomentasthespoileratthe70-percent-chordwisestation.Thepivotedspoileralsohadmoreeffectpriorto theoccurrenceoftheverticalgapandinseveralcasesithadmoreeffectupto 6 percentprojectionthanthespoilerat the~-percent-chordwisestation.

A generalillustrationof theeffectofa smilerontheflowoverawing,baseduponthepressure-distributionmeasurementsofreference1,ispresentedinfigure10. Thedashedareasaheadof andbehindthespoilerindicateapproximatedead-airregions.Thesedead-airregionsareusuallyaccompaniedby a flowcompressionaheadofanda flowexpan-sionbehindthespoiler.Generally,themagnitudeofthenegativeloadingresultingfromthecompressionexceededthemagnitudeof thepositiveloadingresultingfromtheexpansion.Fromfigure10,itcan.be seenthatthedifferencespreviouslynotedbetweentheeffectsofthe

*

8’ ‘“” NACARML72J28

trailing-edgespoilerandthespoileratthe70-percent-chordwisestation.

onthefull-bluntwingweredirectlyrelatedtotheabsenceofanyloadingbehindthetrailing-edgespoilerto offsetthelargeloadingaheadof it. .-

Pitchingmoment.-Thepitching-momentincrementswereverylargeforthetrailing-edgespoilersas comparedwiththecorrespondingvaluesforthespoilerat the70-percent-chordstation.Theselargeincrementsinpitchingmomentforthetrailing-edgespoilermigh~beundesirablebecauseof theassociatedhigh-wingtwistingmoments.Itmaybe seenfromfigure10thatthedifferencesin~itching-momentincrementduetospoilerchordwiselocationweredirectlyrelatedtothedecreaseinloadingbehindthespoileras itwasmovedbacktothetrailingedge.Thepitching-momentincrementsof thepivotedspoileronthe.part~l~bluntwing,wingC, werelessthanat M = 1.41 anda%outthesameatM . 1.96 asforthetrailing-edgespoileronthefull-bluntwing,wingA, atprojectionsbelowthatforwhichtheverticalgapoccurred

(betweenthepivotedspoilerandthesurfaceofthewing $ = io.024.)Beyondthispointthepitching-momentincrementschangedonlyslightlyinmuchthesamemannerasdidtheliftincrementsandrollingmoments. ●

Forthetrailing-edgespoilers,thepitching-momentincrementsusuallydecreasedforupper-surfacespoiler.projectio~sandincreasedforlower-surfaceprojectionsastheangleofattackwasincreaaed.

..-

Thevariationoftheseincrementsathighprojectionsforthefull-bluntwingwaslargeenoughthat,fordifferentiallyprojectedspoilersonoppositewings,anappreciablelongitudinal.changeti...tr~at.m_odera!e_tohighanglesofattackmightresult.Somewhatsmallertrim~~s “-arealsoindicatedforthe70-percent-chord-stationspoiler.trimchangesaremorepronouncedata Machnumberof 1.41andathighanglesofattackbecauseofreversalsinpitching~ment ofthelower-.

.-

surfacespoiler..—.—.—

Dragandyawingmoment.-Generally,thedragincrementsandyawingmomentsf,orthepivotedspoiler(figs.8(d).~.d8(e))_wereconsiderabQ‘lessthantheywerefor.thespoilersonthe.full-bluntwing.‘Thesevaluescomparemorerealistically,however,whenitisrealizedthat -—

thefrontalareaofthepartiallybluntwing(wingC) wasnotincreaseduntilafterthespoilerwaspro~ectedabovetheboat~iledsec-

—

(

—

)

— —tion ~= 5.02 .

Theincrementaldragandyawingmomentsdecreasedforanupper-surfaceprojectionandincreasedfora lower-surfaceprojectionas theangleofattackwasincreased.Thebasemag ofthespoileronthefull-

—

bluntwingat.zeroangleofattackrangedfrom10and~ percentof the ““~ .-totaldragincrementatMachnumbersof 1.41and1.96, respectively, to .*abouttwice that at 8° angle of attack. Thesepercentagesillustrate,

●

NACARM L72J28 9

.

.

aswouldbe expectedfromshock-expansiontheory,thatmoredragwascausedby thecompressionoftheflowaheadofthespilerthanby theexpansionoftheflowbehindit. Theincrementinwingbasedragdueto spoilerprojectionwasinsignificantthroughouttheangle-of-attackrangeatbothMachnumbers.

4Y SweptbackWing

Forthe.trailing-edgespoiler,thevaluesof liftincrement,rolling-moment,andpitching-momentincrement(figs.9(a),9(b),and9(c),respectively),ingeneral,decreasedforan upper-surfaceprojec-tionandremainedfairlyconstantor increasedslightlyfora lower-surfaceprojectionwithincreasingangleofattack.Forthistrailing-edgespoiler,thelift,rolling-moment,andpitching-momenttrendsforupper-andlower-surfacespoilerswereaboutthesameforthesweptwingas theywerefortheunsweptwing. Thespoiler,however,usuallyhadslightlylesseffecton lift,rollingmoment,andpitchingmomentforthesweptwingthanfortheunsweptwing.Forthe70-percent-chord-stationspoilerprojectedfromtheuppersurface,thevaluesof liftincrementandrollingmomentweregenerallyhalfor lessthanwhattheywereforthetrailing-edgespoiler.Forlower-surfaceprojections,how-ever,reversalsinliftincrementandrollingnmmentwereobtainedwithsmalls~ilerprojectionsatmoderateanglesof attackandwithallsmilerprojectionsathighanglesof attack.Reversalsb pitching-momentincrementcausedby theprojected70-percent-chord-stationspoilerwereobtainedwithbothupper-andlower-surfaceprojectionsat smallanglesof attack.Thesepitching-momentreversalsforupper-surfacespoilerprojectionsgraduallydisappearedwithincreastigangleof attackuntiltherewereno reversalsatanglesofattackabove80. Forthesweptwing,them-percent-chord-stationspoilersonthelowersurfaceordifferentiallyprojectedw-percent-chord-stationspoilersonoppositewingsdonotprovidenearlyas satisfactorylift,rolling-moment;andpitching-momentchangesas theydofortheunsweptwing.

Forthetrailtig-edgespoiler,thedragincrementsandyawingmoments(figs.9(d)and9(e),respectively)decreasedforanupper-surfaceprojectionandincreasedfora lower-surfaceprojectionas theangleof attackwasincreased.Generally,thesetrendsweresimilartothosefortheunsweptwing,buttheamountofvariationwithspoiler ‘projectionwaslessinmagnitudefordragandslightlygreaterinmagni-tudeforyawingmoment.Forthe70-percent-chord-stationspoiler,how-ever,thevariationsof dragincrementandyawingmomentwithangleofattackwere,ingeneral,somewhatdifferentfromthosefortheunsweptwing.

NACARM L52J28

ComparisonofSpoilerDataWithFlapData

Thefollowingtableillustratestheeffectofspoilersandflapsontheaerodynamiccharacteristicsof twowingsatanangleofattackof o“:

rPartiallybluntPartiallybluntReference9Reference1

Control

FlapSpoilerFlapSpoiler

h/c 6>deg

5*7-0.04

6.3-ok

0.041o.oo~ -0.02200.0025.041 .00* -.0240 .0134.031 .0043 -.0174 .0041.031 .0043 -.0067 .0244

Includedinthetablearevaluesobtainedfora full-s~n.25-mercent-chord,trailing-edgeflaponthepartiallybluntwing~f{he”m;esentinvestigationat M = 1.96 (unpu~lished)-andonan&sweptw“tiRhaving

-.

—.

anaspectratioof2.5,a taperratioof0.625,and6-Per~enth=xagona~airfoilsectionsat M = 1.90 (ref.9). Also includedarevaluesforthetrailing-edgespoileronthepartiallybluntwingofthepresentinvestigationat M = 1.96 andvaluesobtainedat M = l.~ fr~ refer-ence1 by usingthe55-,65-,and75-percent--chord-stat~onspoilerdatato inte~latefora 70-percent-chord-stationspoiler.(Thesamewingwasusedinbothrefs.1 and9.) Theforceandmcmentcoefficientsobtainedfromreferences1 and9 whichwerebasedonexposedwingareaanda pitching-momentaxislocatedatO.% havebeenalteredto conformtothedefinitionsgiveninthepresentpaper.Thesecoefficients,how-ever,shouldnotbe directlycomparedwiththecoefficientsobtainedinthepresentinvestigationforthe~-percent-chord-stationspoiiers,primarilybecausethemeasurementswereobtainedfroma wingmountedinthepresenceofa bodyandnotfroma wing-bodycombinationaswasdoneherein.Also,a smallgapexistedbetweenthewingand.bodyfortheinvestigationsofreferencesI and9 inadditionto thewingair-foilsectionbeingdifferentfromtheairfoilsectionoftheunsweptfull-bluntwingofthepresentinvestigation.Itcanbe seenfromthetablethat,forequalliftincrementsandrollingmoment(LCL,C!Z),thespoilerscausedconsiderablymoredragthandidthefla-ps~It iSinterestingtonotethatforthepartial-bluntwingthepitching-momentincrements(and,consequently,thewingtwistingmoments)forthetrailing-edgespoilerareonlyslightlyhigherthanfortheflap.Thiswouldindicate onepossibleadvantageofusingspoilers,inthatthehingenmmentswouldbe expectedtobe lowerfqr thespoilerthanfortheflap. It shouldbe pointedoutthat,forequalrolling-momenteffectiveness(C2= O.00~

i, the~itching-momentincrementsforthe

trailing-edgespoileront e unsweptfull-hltitwingarehigherthan ‘“forthepartiallybluntwing(-0.0330ascomparedwith-0.0240).The

e

—

,—

.

NACARM L5QJ28 11

data,however,indicatethesevaluestobemorenearlyeqml atanglesof attackgreaterthanOO. Consequently,thissmilershouldalsocom-parefavorablywitha flapsincethevariationofpitching-momentincre-mentwithflapdeflectionwasaboutindependentofangleofattack.Thetableshowsthepitchingmomentforthe~-percent-chord-staticmspoilertobe lowerthanfortheflapwhichwouldindicatea disttnctadvantageovertheflap;however,aswaspointedout,thisspoilerwasnotaseffectiveasthetrailing-edgespoiler.

Itwillbenotedinthetablethatabout6°flapdeflectionarerequiredtoproducethesameeffectivenessasa spoilerprojected4 per-centof thewingchord.Thisresultwouldihdicateonepossibledis-advantageinusingspoiler,inthatflapdeflectionsinexcessof 6°arelmowntobe practical,whereasspoilerprojectionsinexcessofthethicknessofthewingmayinvolvestructuralproblems.

CONCLUDINGREMARK3

An investigationhasbeenmadeintheLangley9-by l$?-inchsuper-sonicblowdowntunneltodeterminethecontrolcharacteristicsof full-spantrailing-edgespoilersonseveralblunttrailing-edgewingsofaspectratio2.7atMachnumbersof 1.41and1.96.Theresdtsshowedthatthespoilerwasmoreeffectivewhenlocatedat thetrailingedgeofan uusweptor450sweptbackwingthanwhenlocatedatthe70-percent-chordline.Thespoiler,whenlocatedatthe~-percent-chordlineoftheunsweptwing,waseffectiveinproducingrollingmoment;butwhenlocatedatthe70-percent-chordlineofthesweptwing,thespoilerwasnotnearlyas effectiveandtendedtoreverseforlower-surfacepro~ec-tionswithincreasingangleofattack.

Theeffectoftheverticalgapbetweenthepivotedspoilerandthesurfaceofthewingatthetrailingedgewastoreducesharplytherateofchangeoftheliftincrementandrolltngmomentwithprojectionabovea gapof about2 percentchord.

Fromlateral-controlconsiderations(rolltigmoment,wingtwisting?mment,andprobablehingemoments),thetrailing-edgespoileron theunsweptpartiallybluntwingcomparedfavorablywitha 25-percent-chordtrailing-edgeflap.

LangleyAeronauticalLaboratory,NationalAdvisoryCommitteeforAeronautics,

LangleyField,Va.

12 NACARM&G2J28

REFERENCES ● “

1.Conner,D.William,andMitchell,MeadeH.,Jr.: EffectsofSpoiler.

onAirfoilPressureDistributionandEffectsofSizeandLocationofSpoilersontheAerodynamicCharacteristicsofa TaperedUnsweptWingofAspectRatio2.5ata MachNumberof 1.90.NACARM L~120,1951.

2.Hammond,AlexanderD.: Lateral-ControlI&estigati&ofl?lap-TypeandSpoiler-T~eControlson a WingWithQuarter+hord-LineSweep-backof 60°,AspectRatio2,TaperRatio0.6,andNACA6~006Air-foilSection.Transonic-BumpMethod.NACARM LmE09,1950.

3. Fikes, JosephE.: HingeMomentandOtherAerodynamicCharacteristics—

atTransonicSpeedsof a Quarter-SpanSpoilerbackWingofAspectRatio3. NACARM L5f2A03,

4.ChapmanjDeanR.: ReductionofProfileDragatby theUseofAirfoilSectionsHavinga BluntRMA9H11,1949.

5.Cleary,JosephW.,andStevens,GeorgeL.: The

ona Tapered45°Swept-1952.

—SupersonicVelocitiesTrailingEdge.I?ACA .—

EffectsatTransonic .SpeedsofThickeningtheTrailingEdgeofa WingWitha 4-Percent--ThickCircular-ArcAirfoil.NACARMA51Jll,1951.

6.Burgess,WarrenC.;Jr.,andSeashore,FerrisL.: Criterionsfor—

Condensation-FreeFlowinSupersonicTunnels.NACATN25M,1951. -

7.May,ElleryB.,Jr.: InvestigationoftheEffectso?Leading-EdgeChord-EtiensionsontheAerodynamicandControlCharacteristicsofTwoSweptbackWingsatMachNumbersof1.41, 1.62, and1.96. NACARML~L06a, 1971.

8. Conner,D. William: AerodynamicCharacteristics of TwoAll-Movable ..—WingsTested in the Presenceof a Fuselageat a MachNmuherof 1.9.NACARM-04, 1948.

9. Mitchell,MeadeTrailing-EdgeofanUnswept

H.,Jr.: EffectsofVaryingtheSizeandLocationofFlap-me ControlsontheAerodynamicCharacteristics_Wingat a MachNumberof 1.9. NACA~ L50F08,1950.

.

.

, ,

‘“”~ ,..------d

I ,,m ti2.-

Sutlm Edlu.

I

Figure1.-De~silsofaemispan-wingnmdelsAlldimensionssreti

withtrai~ng-edgespoilers.inches.

—

I/

—

—

.Am

,7

h

I’t

?i

I i

--—- ? .0

— a.sm >:;

A.

Pr=

s‘?K!

Figure2.-Iletailsof semispan-wingmdel with pivoted trailing-edgespoiler. All dimensionsare in Inches.

1.!,

;, ‘!‘]1,

.1

‘i;,1

,~!,,,,

,,.

‘1,

I

.

I ●

.

Figure3.-Photographof semispen-wimgnmdel with pivoted traiking-edgespoilerdeflected. All diniensionsare in inches.

I

I

I

.

16

/.0

.8

.6

.4

,2

0c~

:2

-.4

-.6

:8

- /.0

Figureh..

.02 .04 .06h/c

=1. IU; R-1.6X

Aerodynamic

(43)n 16.01013.990 11.99d 10.00A 8.o2A 6.0

z8 9:;6o .06V-1.94

!!2.:3.9*0-3:!00-10.07W-L?.M

n

NACARM L52J28

o .02 .04 .06

.

.

.

/?/c~06 M= 1.96;R.lm3xlo6

(a) Lift..

characteristicsof anunsweptsemispanwingwitha trailing-edgespoiler. —. .. .

— ..-—...- .

NACAw L52J283s

.

.

*

./0

.08

.06

.(24

.02%gross

o ●02 .04 .06h/c

M= 1.41;R-1.6X 1($

(d:g)

n

(b) Grossrollingmoment.

Figure4,-Continued.

o .02 .04 .06h/c

M= 1.96;R-1.3x11+

NACARM L52JZ$

.

.24

.20

./6

./2

bORcm

.04

0

-.04

-.08

~f20 .02 .04 .06

(L3:g)

u -=.4g -10.07- 8.00: ~3:;’v 0!!- 1.9

! $:$2 1:::0c1 11.990 13.99a 16.01

,Il_

0 .02 .04 .06—We

M= 141;R-1.6X

h/cd M= 1.96;R=1.3xId

(c) Pitchingmoment.

Figure4.-Concluded.

.

.

—

.

NACARM L52J2$ 19

.

.

.

.

1

WingB

o .02 .04 .06h/c

~=1.41: R = 1.6 X 106

(a) Lift.●

0 .02 .04 .06h/c

M = 1.96;R = 1.3x 106

Figure5.- Aerodynamiccharacteristics of a 45° sweptbacksemispanwingwith a trailing-edgespoiler.

..

20 ~L NACARM L52JE%

o .02 .04 .06h/c

o .02 .04 .06hlc

.

:

.

.

M=l.41;R = 1.6X106.. M = 1.96;R = 1.3x 106— .—

(b) Grossrollingmoment.

Figure5.- Continued..

NACARM

.24

,20

./6

./2

.08

.04

0cm

-.04

:08

:/2

:/6

:20

L52J28 ~

m-q B

21

o .02 .04 .06 0 .02 .04 .06wc h/c

u= i.l+l; R = 1.6x106 M=1.96;R = 1.3x 106

(c) Pitchingmoment.

Figure5.-Concluded.

—

.8

.6

.4

.2

0

Q

:2

:4

:6

(&g)G IL.wG 12.00j 1:.01

“?A 6.0$ $.;$

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j Ejg

C-lollcF12.17

,, i.

n

o .02 .04 .06 .08 ./0 o .02 .04 .06 .08 .10h/c i:!. h/c

M= ~.lu;E = 2.3 M 106 M=l.WR=l.9 X106 .

(a) Lift.

Figure 6.-Aerodynamiccharacteristicsof an unsweptwing (with trauai-tion strips)with a pivoted trailing-edgespoiler. Flagged symbolsdenote data obtainedat a different dete fmm originaldata.

,, . .1,

if

~“I

1

!J

.08

,06

. ,

.04

.02

0

CZgross

702

704

706

708

(dg)o 11+.oon 12.ocd 10.01

i %$4-sK?/o - .07

Yg :;:3~ :~;g

o -10.Un -K.17

o .02 .04 .06 .08 ./0 o .02 .04 .06 .08h/C

./0

h/cM=l.bl; R=2.51rlcf’ H E 1.96;R = 1.9x 106

(b) Gross rollingmoment.

Figure 6.- Continued.

,

!2

.12

.08

.04

cm

o

:04

:08

-.12

o .02 .04I)/ c

.06 .08 ./011, ,

M=l.41; R= 2.3 xl+.

(c) PitcMngllrment.

Figure 6..COnCltiM.

1

-04 .06 -08h/c

./(2

&N

ii

4s

.

.

NAM RM L52J_28

.

.

—

n wingA

n/

/

/

d

a = -60

.Z .4 ,6 .8 /.0~&/2 (exposed semiapan)

a=6°

ou wing alone

whg 8ndspoiler

(a) M = 1.41;R = 1.6X 106.

Figure7.. Effects of a trailing-edge spoiler projectedpressure of anunsweptsemispanwing.

0.06conthebase

f’b

‘b

‘b-./

o

\/ o-

0 ,

= s -150

kl-

=Zoo .2 .4 ,6 ,8 LO

.

-.

—

am@ ..--.nWingA

0 Wing alone❑ Wing and spoiler

..-M, . —

z

(b) ~= 1.96;R= 1:3x10%.

Figure7.-Concluded. . .-

* *

.2

Elf

o.\dcf

-.2..00

.#?

oAGL

-.2 H

.04

02

Ii!l

q o --

:0.2

o h/c”06

1$1113,- --.=4” ..@

lfIEF1’J-lfH3ii(a) Lift increment.

- l.bl

:06 0 .06 :06 0 .06h/c h/t?

(b) Rollingmmnent.

..-. —

-nh:}wingA——

-–---— —“ ling c

Ei!-0 /),.”06

Figure 8.- Lncremsntsin aerodynamiccoefficientsdue to a s~ilerprojected at the yO-percent-chordline snd at the trailing edgeof an unswept semispanwing and incrementsdue to pivoted spoilerlocated at the trailingedge of a relatad unswept semispanwing.

.12

.(X

.04

0AGm

:04

T08

-. lb?

a=oo

.08

.04

0Ac~

:04

7080

wc.06

,

M= 1.IJ1

a=tp a.p

-’

M =1.96

?06 Oh/c

.06 706 0?Vc

.06

(c) Pitching-mment increment.

Figure 8.- Continued.

. .,, :,.,.

n

a.tio

0h,c”06

,

.10

*o8

.06

.04Qco

.Gi?

o

702

.08

.06AGo

.04

.02

0

a=oo

o .06hfi

a=u’

K= 1.41

m= 1.96

, , . *

S.8°

n.

❑o—

——,:}

------ —“

❑ ?lIrq.baae-dmg inaremllt

o spoilerhoe dlug

.X=*O

IiIii;06 O ,06 706 0 .06 0 .06

b/c h/c h./c

lIw. A

wing c

ma ta Pm@otad

.

apoik.r

(d) Drag increment.

Figure 8.- Continued.

LL.1o

0

c“

:Of Ff13---

‘.

m = 1.IJ1

n

a= o”’ .=4° .2=8°a.llp

l———HHl H+++HlHH—H—t—t

}.

Wing A

wing o

Cn 1111 1111111;02 U_J-.J Lu_u_L_l M kBl-

0 ,06 ‘.06 O “ .06 :06 0/)/ c

“ .06 0 .06w c 1 h/C h/c

(e) Yewing nmtint.

me 8.- Concluded.

,,,1

*

. ., ”,”‘; ;1 i,” ,1’’!!:

..?

ACLO

-.??EIla-on

.2

.

AC:

-.2 H

.02

clo

-.02 H..00

, . ,

B3EEIEE!BIa-ho a-w . . 16° a.2p

EfElimmm(a) LcLft increment.

.=lf ..8” a=ti” a . 250

(b) Iblling moment.

Figure 9.- Incrementsin aerodynamiccoefficientsdue to a spoiler wprojettedat the yO-percent-chcnxlline and at the trailing edge P

of a 450 weptback semispenwing.

./2

.08

04

0Zlcm704

-.08

7/2a=rJ’J

.08

.04

0Ac’704

:08

~=.9°

.

a=16°

J

0 .~ ‘.06 o .06 ;m o 06 ;06 o .06 -.06h/c o .06

h/c Wc h/o h/c

(c) Pitching-mmentincrement.

Figure9.-cont~ued.

-,

,

a?

.06

.04

flc~

.02

0

a=OO

.06

.04

.02m~

o

:020 .C&&c

, .

a=8°

-06 0 .06 :06 0 .06MC Wc

z’

, ,

.

-.06 0 .06 -.06 0 .06Wc be

(d) Dragincremsnt.

Figure 9.- Continued.

wu

.

.01

0c~:01

702 E131

a.o”

.(2/

oc//70/

-.02o ,(M -,06 0 ,06

lvc we

* .

a=a”

-.06 0 .06h/c

a u 16° a = 25°

706 0 .06 -.06 0 ,06Al/c h/c

,1

(e) Yawing wntent.

,Figure 9.- concluded.

, .I 1,, ,,

*

,. .

7’shock

~gpoiler

\

\

Figure 10. - Effect of a spoileron the flow over a wing.