1、,., ,./,.NATIONALADVISORY COMMITTEEFOR AERONAUTICSTECHNICAL NOTENo. 1643EFFECT OF LANDING FLAPS AND LANDING GEAR ON THE SPINAND RECOVERY CHARACTERISTICS OF AIRPLANESBy Lawrence J. GaleLangley Memorial Aeronautical LaboratoryLangley Field, Va.,=qJ-j7WashingtonJune 1948Provided by IHSNot for ResaleNo
2、reproduction or networking permitted without license from IHS-,-,-. .NATIONALADVISORYCOMMITTEEFORAERONAUTICSTEf2EKtCALNOTlZlO.- 1643EFEECTOFLANDINGFLAPSANDLANDINGGEARONTHE SPINANDRECOVI!XYCHARACTERISTICSOFAIRI%ANISBy LawrenceJ. GaleThe effectoflendingflapsandlandinggearon thespinandrecqverycharacter
3、isticsof airplaneshas been determinedfrominvesti-gationsof the spinningcharacteristicsof 58modelsin theLangley1-footend20-footfree-spinningtunnels.The analysisindicatedthatgener.lyan adverseeffectonreuoverycharacteristicswas obtainedwhentheflapswerein an extendedpositionduringthe fullydevelopedspin.
4、 An exceptionto thiseffectoccurredwhenthemodelwas heavilyloadedalongthefuselageandtheaileronswere setwith thespin,forwhichconditiontherewas eitherno effector a favorableeffectonrecoverycheractthe investigationincludeda determinationof theeffectof extendinglandingflapsandlandinggearuponthe spinandrec
5、overycharacteristics.Becausepresentmilitaryspecificationsdo notrequireairplanesto demonstraterecoveryfromfullydevelopedspinswhen in thelandingcondition,investigationsof spinmodelswithlandingflapsendgearextendedhavebeendiscontinued.Datafor58modelsareavailableat theLangleyLaboratory,however,fromwhicht
6、he independenteffectsof eitherlani flapsorinegativewhenmassis distributedchieflyalongthefuselage)anglebetweenfuselagereferencelineandvertical(approxi-matelyequalto absolutevalue of angleof attackatplaneof symmetry),degreesanglebetweenspanaxisandhorizontal(positivewhenright,or inboardwing,isbelowhori
7、zontalIn a rightspin),degreesfull-scaleangularvelocityaboutspinaxis,revolutionspersecondTESTSanalysisin thein theLangley1-footThe steady-spinandrecoverydatausedforthepresentpaperwereobtainedfromroutineteetsmadeand20-footfree-spinningtunnelsduringthelastlayears. I?atafroma totifrecoveryis effected,th
8、emodeldivesor glidesintoa safetynet. The spindataobtainedfromthetestsarethenconvertedto correspondingfull-scalevaluesby methodsdescribedinreference3.The dataconsideredhavebeenobtainedfromresultsof testsfornumerousairplanemodelsin theLangleyis-footand20-footfree-spinningtunnels. Someof thedatapresent
9、edarefromtestswithlendingflapsandlandinggearextendedin conunctionwithan opencanopy. Resultsof unpublisheddata,however,haveindicatedthatcanopyopeningalonehas a negligible“.The resultsto 6. Figures1characteristics,effectonmodelspinandrecoverycharacteristics.RESULTSANDMEIYIOIMof thepresentinvestigation
10、aregivenin figures1to 3 indicatetheeffectof flapsuponspin-recoverywhereasfigures4 to 6 indicatetheeffectof flapsupontheangleofwing inclination,angleof attack,andrateof -rotation,respectively.Themodelnumbersassociatedwiththepointsin figures1 to 6 forallelevator-upcontrolsettingscorrespondtothenumbers
11、in tableI. TableI presentsscmeof the princiL massanddimensionalcharacteristicsof themodelsusedin thisinvestigation.Extensionof thelandinggearhad onlya smelleffecton the spinendrecoverycharacteristicsof themodels;and,consequently,no plotspertaining to theeffectsof landing-gearextensionarepresented.Sp
12、in-tunnelexperience(references4 end 5) has indicatedthattheIx - Iyinertiayawing-momentparameter w greatlyinfluencethemb2effectofrudder,elevator,ailerons,andslotson the spinendon therecovery. Sinceflapsseemedto showa dependenceon thisparameterandno relationto severalothertiportantmassenddimensionalpa
13、ram-. etersconsidered,theeffectsof landingflapswerethereforeexeminedin relationto the inertiayawing-momentparaeter. Accordin.y,thenumberof turnsrequiredforrecoveryby rudderreversalwithflapsin. a retractedpositionandwithflapsin an extendedpositionwereccmperedas a functionofthe inertiayawing-momentpar
14、ameter.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-4 NAC!ATN No. 1643When themodelentereda steephigh-velocityspinwhichcouldnotbe controlledinthetunnel,recoverywas estimatedto be rapidandapointwas arbitrarilyplottedasrequiring1/4 turnfortherecover
15、yby rudderreversel.-Forrecoveryattemptsinwhichthemodelstruckthe safetynetbeforerecoverycouldbe effected,thenwiberof turnsfromthetimetherudderwasreversedto thetimethemodelstruckthesafetynetwasrecorded=Thisnumberindicatesthatthemodelrequiredmoreturnstorecoverframthespinthanshown. A greaterthan2$-turnr
16、ecovery,however,doesnotnecessarilyindicateen improvementwhencapered witha greaterthenk-turnrecovery.Forrecoveryattemptsinwhichthemodelrecoveredof itsownaccord,withouta reversal.of therudder,theconditionknownas %o spin”was plottedat zeroturnsforrecovery. The syribol indicatesthitmsy thereforebe concl
17、udedthatluweringthe flapsusuallyb causeden increasein inwardsideslip. (Sideslipangleequals minushelixangle.)Theresultspresentedin figure5 indicatethatthe angleof attackof the spinningairplaneinmost of the casesincreasedwhenthelandingflapswereextendedin thespin. Figure6 indicatesthatgenerallyforthemo
18、delstestedtherateofrotationdecreasedwhentheflapswereextended.It shouldbe notedthattheelevator-neutralandelevator-downdatawerepresentedin figures4 to 6 merelyto substantiatetheconclusionsreachedfortheelevatar-updata. ,Brieftestsweremade fora contemporarylow-wingfighter-typeairplaneattachedto a rotary
19、balancein theLangley20-footfree-spinningtunnel. The forcesandmomentsactingon themodelweremeasuredwithflapsextendedendwithflapsretractedwhilein a simulatedspin. Theresultsof thesetestsindicatedthatusuallythe incrementin antispinyawingmomentcoefficientdueto reversingtherudderwas apeciably-.lesswhenfla
20、pswereextendedthsnwhen theywereretracted.Theseresultsarein agreementwithfree-spinningtestswhichindicateanadverseeffectof extendedflapsonrecoveryby rudderreversal. The-. resultsalsoindicatedthatforspinsofmoderatesnglesof attack(c.%between35 and 55), the aerodynamicdiving-mcmentcoefficientincreasedwhe
21、nthe flapswereextended.Resultsobtainedfortherolling-momentcoefficientinU.catedsmallchangesdueto loweringflaps,andnogeneraltrendwas indicated.It appearsthatrecoveriesfromfullydevelopedspinsmsy beseriouslyreterdediflandingflapsarein the downposition,and,accordingly,fullydevelopedspinsin thelandingcond
22、itionshouldbeavoided. If a spinis inadvertentlyenteredwithflapsduwn,the flapsshouldbe retractedimmediately.At thepresenttime,militaryairplenesarerequiredto recoverfroml-turndemonstrationspinswithflasdown.Experiencehas indicatedthaten airplanedoesnot entera fullydevelopedspinin1 turn;and,therefore,fo
23、rthiscasetheeffectof flapswillprobablybe smellWith theadventof jetairplaneswiththerelativemassdistributionalongthe fuselsgegreatlyincreased,the observationhasbeenmade inmanyinstancesthatthe spinningmotionconsistsprimarilyof a sequenceofrollingandyawingoscillations,particularlyfora designincorporatin
24、ga longnoselength(reference6). It isbelieved,however,thatingeneralthe conclusionsreachedin thisreportarealsoapplicableto-.thesejetairplanesJProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-6 M!lkTN0. 1643AS previouslyindicated,althoughnotpresentedin c
25、hartform,theresultsindicatedthatan extensionof thelandinggeerseldm had aneffecton thesyin-recoverycharacteristicsofnbdels. Whereeffectswerenotedtheywereusuallyfavorableandrecoverieswerehastenedsl.ghtly.Occasionally,adverseeffectswerenoted,probablydueto acriticalchangeinmass-distributioncausedCONCLUS
26、IONSOn thelasisofthe analysispresentedby theextension-ofthegear.of theeffectoflandingflapsand.landinggearonthe spinend,recoverycharacteristicsof -58 airplane models,the followingconclusionsmay be drawn:1.Extendedlandingflapsusuallyhad an adverseeffecton theApinreccmerycharacteristicsof en airplane.A
27、n exceptionoccurredwhenthemodelwas heavilyloadedalongthe fuselageandthe aileronsweresetwiththespin,forwhichconditiontherewas eitherno effector a favorableeffectonrecoverycharacteristics.It thusappearsthatif a spinis enteredinadvertentlywiththelandingflapsextendedtheflapsshouldusuallybe retractedimme
28、diately.2. Loweringflapsgenerallycauseden increasein inwardsideslip,an increasein the angleof attack,anda decreaseintherateofrotationof themodelin thespin.teton ofthelung gem genera hadno appreciableeffecton the spin-ecoverycharacteristics.A-.LangleyMemorialAeronauticalLaboratoryNationalAdvisoryComm
29、itteeforAeronauticsLangleyField,Vs.,March18, 1948.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACATN No. 1643REFERENCES7A1. Bsmber,M. J.: AerodynamicEffectsof a St Flapon theSpinningCharacteristicsof a MonoplaneModel. NACATN NO. 515,1934.2. Neiho
30、use,Anshal.I.,LichtensteinjJacobH., andepoon,PhilipW.:Tail-DesignRequirementsforSatisfactorySpinRecovery. NACATNNo. lokj1946.3. Zimmerman,C. H.: PreliminaryTestsin the”N.A.C.A.Free-SpinningWindTunnel. NACARep.No. 557,936.4. Neihouse,A. I.: A Mass-DistributionCriterionforPredictingthe .Effectof Contr
31、olManipulationon theRecoveryfrcxna Spin.NACAARR, Aug. 1942.5. Neihouse,Anshal1.,endpitkin,Mervin: EffectofWingLeading-EdgeSlotson theSpinandRecoveryCharacteristicsofAirplanes.NACAARR No. 3D29, 1943.-. 6. Stone,RalphW., Jr.,andKlinar,WelterJ.: The InfluenceofVeryHeavyFuselageMassLoadingsendLongNoseLe
32、ngthsuponOscillationsin theSpin. NACATN No. 1510,1948.-.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-“8 NACANo. 1643TABLEI.- PRINCIPAL MASS ANDDIMENSIONALCEMACTERISTICSOFMOIELSUSEDINFLAPIIWXSTIGATIOIiOae:12:567;101112:15161718192021222324252627282
33、930g32333435363738%4142:?454647484950wingEpan(ft)42.00123.0051.5055.0064.0042.0083.0066.0052.50Q.3391.8340.7e59*6E41.4465.0040.7g45.6C47.7042.0042.0040.-R53.6535OC35.0040.0333.X36.0041.Oc53.0034.3341.5139.CO36.0037.X38.GO42.0034.0034.0041.0236.cQ48.0042.0345.0040.0054.0036.0042.0037.29k.oo37.2836.00
34、38.0038.00wingarea:Eqft)303.50.6u+-L5.989.9516.2115.7313.4011.9710.9714.4313.1416.403.6417.13n. 3214.2211.8510.49L5.05;$7.9717.13xl.44K.7210.287.88U.9013.014.B19.6616.72io.029.196.89U. 851.L186.6512.710.08.g.19.9010.5115.3117.6513.297.445.4314.7810.0814.41;27.49(SPYfeet)13!793804,26340,08741,9;?/(s2
35、%fe)7,570,79325,59525,59639,9937,17405,41035,0fQW01624,55793,10013,04719,934%9$4,97016,5457,6774,1224,36013,04722,5b54,5603,71.54,1702,8715,7698,00729,w85.5408,6925,9315,7104,4704,9963,7J.56,u33,6854,2375,1153V#25,533Ll,63544,5866,5543,4906,74428,4k37,3875,7779,5008,739g:?,21,210.,259,5I.864,15163,t
36、525104,14217,2642;60037,83217,33063,2637,476:,%710;0008,W6,977u.,eoo10,712TRPF?410x 10-6tl:473732442204$313U53a1:;!017397238k5233562343460446 -0.0634.0465.0356.0241.0363.0478.0080.ql(l.0464.0280.0030.0164.0212.0195.0411.0169.0320.0087.0140.0168.0164.0184.0171.0120.0178.02$0.0144.0173.0233.0268.0206.
37、0096.0185.C+.0079.ol 19.I I #Ii - 2xtendlng flapa impairedrecovery charaoterls tlos46!, IIII I2xtendlng flaps improved11 I kIncc.v=ry Charaoterlsths# -Arrow abve symbol IndiontesI IImodel required more thanI indicated number of turns H+I 11 I III I 1,II I Ip-“ I 26” ;pIspin n Q XT19 “%.4.npin 1I I I
38、 I I t 1 1 # t-2t40 -240 -200 -160 -120 -ao -v .-1X - IyInertia yawlnpmomen% Parmmeter, _=S9=mi+Figure 2.- Effect of landing flaps on the recovery characteristics for spin models with variousinertia yawing-moment parameters with ailerons against the spin and elevator up.(Numerical values placed near
39、 data refer to model numbers listed in table L)Po. .,r* .Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-a . , , bStew high velocityNom Al11ClFlaps retracted.A Flaps extendextenslon or flapsindicated no efrect II9 - A- A tit ending rlaps impaired “ w
40、recovery characters tlos IExtending rlaps improved !3recovery characteristics 1 -i1:! IIg. possible with flapB : extended911 . 4:3: I IuI %2 .+”: -.,+,-;. bY ill- 111 Yl 6! ! Two mln conditions2 I I I I I I I J I l,-II c1+ “ ” “p. -.- -”POSSible with flaps A r3 possible with rlapsretracted retraoted
41、1 ,I 39 Y I49 W& I,Spin -B, A !?I /rb2I spin-260 -240 -200 -160 -120 -go 40 0 40 4IneI.tla yawing-moment parameter, IX - Y 0 *, II IFigure 3.- Effect of landing flaps ontherecovery characteristics for spin modek with variousinertia yawing-moment parameters with ailerons with the spin and elevator up
42、.(Numerical values placed near data refer to model numbers listed in table I.)Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-LElevatorposftlon753101357qAgaInstNeutral DownNeutralup9&30.PO“2/3DownFlap position0 indicates flaps retracted indicates fla
43、ps extendedWIthup Neutral DownFigure 4.- Effect of flapson theangleofwing inclination during the spinfor various controlsettings for free-spinning-tu.nnel models (right erect spins). (Numerical values placednear elevator-up data referto model numbers listed intable L), *. .FProvided by IHSNot for Re
44、saleNo reproduction or networking permitted without license from IHS-,-,-s ,*“”S70-/. 3160- 2g$53.4$50- :7040-o304320 L-NeutralJDown-Neutralup4720Neutral I DownI. Withup)274#9$12.l.” .7 6.10.eutral- DownFla ositlon indicates-fiaps retractedA indicates flaps extendedFigure 5.- Effect of flapson the a
45、ngle of attack during the spin for various control settingsfor free-spinning-tunnel models. (Numerical values placed near elevator-up datarefer to model numbers listed in table I.) PLA)Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-&Aileronposition
46、AgainstElevatorposition up. i?!o.70.60.20Figure 6.-SettirlgsIeutral DownNeutralup47&leutralG-ADownFlappoaitlon indicatesflapsretractedA indiaatesflapsextendedWithup Neutral Down1-I=Effect of landing flaps on the rate of rotation during the spin for various controlfor free-spinning-tunnel models. (Numerical values placed near elevator-updata refer to model numbers listed in tabk I.).u # , *, ,9. -.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
