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Aerospace Engineering - Airplane performance and dynamics

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Complete course

Airplane performance and dynamics Glossary -E:LIFTTO☐RA0RATIO• ] iANGLEOFCLIMB•V0:RATEOFCLIMB.VV:POWERLOADINGPbiW''WINGLOADINGs'J:DENSITYRATIO INTRODUCTION TOTHEAIRCRAFTDESIGN•MAINPHASESOFTHEDESIGNPROCESS: 1) CONCEPTUALDESIGNGENERALCONFIGURATIONOFTHEAIRCRAFT ( ARCHITECTURE)INITIALSIZING:MT0W Pb( POWEROFSHAFT ) T / THRUST)5/WINGSURFACE:ITINCLUDESTHESECTIONOFTHEFUSELAGE)-s2) PRELIMINARYDESIGN 3) EXECUTIVEDESIGNMISSIONREQUIREMENTS1)PERFORMANCESPEEDSSTALLINGSPEED:MINIMUMSPEEDWHICHALLOWSTOSTAYONFLIGHTMAXIMUMSPEEDBESTRANGEECONOMICSPEEDS:BESTENDURANCEMAXRATEOFCLIMBMANEUVERINGSPEEDa--RANGEENDURANCETIMETOCLIMBTA K EOFFDISTANCELANDINGDISTANCE 2) PAYLOAD3)PRESSURIZATION'ITISCONSIDEREDINMISSIONREQSBECAUSEITALLOWSTOFLIGHTOVERACERTAINItEIGHTMISSIONPROFILE'T0DT0C.CRUISE.LOITERT0C:TOPOFCLIMBaTA X I.LND..T0DiTOPOF☐C-SENTABCDIVERSION•DIVERSION:IT'STHEB-PLANWHENTHEPILOTCAN'TLANDINB•THISSCHEMEALLOWSTOAT TAC HFOREVERYPHASEITSMISSIONREQUIREMENTS:BR:BESTRANGECONDITIONMINIMUMFUELCONSUMPTION..RD:RATEOFDESCENTTIPICALLYLINKEDTOTHEPRESSURIZATIONOF⑥"""£°""""°""£&""AC:ANGLEOFCLIMB.BEiBESTENDURANCE'.IrABPUNTUAL PERFORMANCESDRAGPOLARCL((MAX-EMAX.E:=LIFTTODRAGRATIO[DM1N'ICD0CD PENAULDDIAGRAMSD-min(D)✓STALL✓PrtgO =Pr=D-Vmin/Pr)..thinkVminDV✓STALLVmaxfVmaxEANALYTICALPOLARCL.--. i -aCD[☐=[☐☐+ KCLZ i. ...CLE=CLMaxE=minDCDE.MAX..FMAXF=ECLMaxF= minPr ( °""G=Emax6= min D+ V22 TRACKAnote:2=atanV2£3£2V1 BODYFRAME• B=/ o, /be, bz.bz/I iROLLAXISINTHEDIRECTIONOFTHENOSE•• by "¥2"PITCHAXISINTHEDIRECTIONOFTHERIGHTWING••-b-2ab-3b-3"YAV VAXISWHICHISPOINTINGDOWNRESPECTTOTHEPILOT• it = I + I + I •F=F?by + F2Bbe + Fz°be = I b-a+ IK2 + Ib-3---•mp= My + [ p+ Hf AERODYNAMICMOMENTWEIGHTMOMENTPROPULSIVEMOMENT•my= Isby + Mpbz + Upb?•SPEEDS:Yp=up by +Up by +up bz •ANGULARRATES: I = pby + 9b-2+1- b- 3AIRSPEEDVECTORINLOCALHORIZONFRAME• I =v1 ey +V2e-2-Vuez =V1 Ee +v2 ez -vsin8ez Iv.vf.c o£"¥vhUh=VCOST2 | "¥= vent£3£2I=✓cos ✗ cos2ey+vcostsin2ez -✓sin 8e- 3 •ANGLEOFSIDESL1Pi kn pI f. =asinto=asintobe •• by ✓ve•ANGLEOFAT TAC K'••bya✗=atanwwIb-3AIRSPEEDVECTORINBODYFRAME•I=in by +to be +wb-3 it +W2=V COSP ⑥w=utan,±=✓0no / ✗*+ d) aoCONDITIONmo✗>53)✗= bZ SAME5T,BUTITs✗•✗a=✗a"a"t✗ATIT=✗ I -at/✗a"-✗ I a.+ata+at>0>☐•THETA I LPULLSBACKWARDSTHEAERODYNAMICCENTEROFTHEPARTIALAIRCRAFT-✗it✗ACI✗AC-/a✗W✗Ac✗Ac✗ACT•INACANARDCONFIGURATIONTHEAERODYNAMICCENTEROFTHEPARTIALAIRCRAFTISPULLEDFORWARDS,SOSTABILITYISREDUCED✗a=✗ I a"t✗ATIT=✗ I -at/✗a"-✗ I a.+at2+2T☐a6.✗✗ATEXACa-°''✗✗ACT✗Ac✗AC" CENTEROFGRAVITYTRAVEL(A=It+ e) W(✗/✗-✗☐ 1=11 +e)W I &,✗L'=-ew Ls/5-So/=-ew✗a✗A•STABILITY:✗G-✗A7O'NEUTRALSTABILITY:✗G-✗A=0INTHISCASETHEACISCALLEDNEUTRALPOINT✗-do✗o✗oeS- So &,&,••✗6✗ § - SO MOREDEFLECTIONMORESTABILITY,LESSCONTROLLABILITY•THEMAXIMUMCGTRAVELDEPENDSONTHEMAXIMUMDEFLECTIONGEMAX•✗=✗☐t(t+e)THERE'SAE.MAXDUETOTHEFACTTHAT✗MUSTBELOWERTHAN✗STALLLt•CGDEPENDENCIES:✗GAFT:STABILITY✗6FWD:MaxSeSTALLFS(FORCEONTHESTICK)iF15IOLOGICALLIMITATIONTHEPILOTMUSTBEABLETOCONTROLTHEAIRCRAFTPOSITIONCONTROLFORMULATION•UPTONOWWEHAVEBEENLOOKINGATPOSITIONCONTROL,INWHICHITDOESN'TMATTERHOWBIGTHEFORCESAREORTHEPILOTBEHAVIOUR''et's'"""°'"c-"""'surface:✗bHe/a.5.e)=Hey/✗-to)+He getSe-Seo)+HeoHINGEMOMENT✗TÉL Se >0 L/a.Set -•POSITIONCONTROLMG20,041)PHUGOIDMODE:LEVEL2:5pm>0LEVEL3:T2>555 / UNSTABLEPHUGOID)2)SHORTPERIOD: S CAT.ACCAT.BLEVEL10,35-1,300,30-2,0MINIMAMAXIMAFORDAMPINGLEVEL20,25-2,000,20-2,0LEVEL30,15-NOTDEFINED0,15-NOTDEFINEDCL1 guZSCcg.tn 2 UF5P a^WHYWEUSETHISFACTOR:A=L.I==I fv25 [(ghXXUX✗2WLOADFACTORINCREASEFORLOWERWEIGHTS•AINCREASEFORHIGHC-ISPEEDaINCREASEFORLOWERALTITUDE 2WSP-t(nt)CAT.ACCAT.BCAT.CLEVEL10,28-3,60,85-3,60,16-3,6•..LEVEL2'','',LEVEL30,G-NOTDEFINED0,6-NOTDEFINED0,096-NOTDEFINED•TOSUMUP,CONCERNINGLATERAL-DIRECTIONALBEHAVIOUR:1)ROLL-SUBSIDENCEiCONSTRAINEDinTERMSOFMAXIMUMPERIODT2)SPIRAL"CONSTRAINEDINTERMSOFMINIMUMT23)DUTCH-ROLL:CONSTRAINEDWITH:MINIMUMWdrMINIMUM§d✓.UrduMINIMUM §dr ESTIMATIONOFCOEFFICIENTSINTHELONGITUDINALPLANE•✗-FORCE:•me/INERTIA),Ce(GEOMETRY)•[✗ in ,[✗É,[✗µ,[✗0,[✗✗,[✗ofSTABILITYDERIVATIVES ( 02REFERENCEFORCEVA LU E S)•[✗Se,[✗STCONTROLDERIVATIVES•2--FORCE:•my,CY•(2-in,[2- I , Ctu ,[Z01CZ✗,[2-of•[zSe,CZST•Y-MOMENTi•C1,JY1• CM6E ,[ Moni , CM6M ,CM60,[moon,CM09"or Cmoge ,[MOST•inORDERTOPROVIDEANAPPROXIMATIONOFALLQUANTITIESTHEREAREDIFFERENTTECHNICALSOLUTIONSi-FORINERTIAANDGEOMETRY:1.CADSYSTEMS2.DIRECTMEASUREMENTS3.MODELIDENTIFICATION(FLIGHTTESTING)-AERODYNAMICS ( STABILITYCONTROLDERIVATIVES ) :d.ANALYTICANDSEMI-EMPIRICALMODELS2.CFD3.WINDTUNNELFLIGHTTESTING•INAPRELIMINARYDESIGNPHASE,WHENTHEAIRCRAFTGEOMETRYISN'TKNOWNYET,COMPUTATIONALORANALYTICSEMI-EMPIRICALMETHODSAREBETTER•LET'STRYTOFINDACONNECTIONBETWEENL1DANDZ,✗.THISCANBEDETERMINEDASFOLLOWS:CONSIDERANEQUILIBRIUMCONDITIONINFLIGHT,INPARTICULARHORIZONTALFLIGHT✗FORCE,ALONGb-1:WHATHAPPENSIFWEHAVEAPERTURBATIONIN [ ,BOTHININTENSITYANDDIRECTION? LotLgtob-aXot✗Dot☐✗☐Wedo/v0✗✗V.+ViDowib?•LET'SWRITEAFORCEEQUIVALENCE:•✗☐+✗= /LotL) sin / to-1 a) -/Do+ D) cos/Lot a) •BEFOREPERTURBATION:✗☐=tosin✗0-DoCO5X☐•sin/✗otd)=sintho+cos✗☐& | t.oesmau.sn•cos(do+ d) =cosdo-Sinto✗•SUBSTITUTE:✗☐+✗= / to+L)( Sando+cos✗☐ d) -IDo+ D)/ COSXO-sin✗☐ d) •✗☐+✗=toSisto+Locosdoa+LS1Ndo+LCOSXO✗-DoCOSXO+DosindoX-DCOSXO+DSanto✗'REFERENCECONDITION/BEFOREPERTURBATION)•HIGHERORDERINFINITESIMALS✗=Locosdo✗+Lsindo+DoSisto✗-Dcos.to✗=1 guts/ c.✗a✗+ / cxu+zcxo ) ie)2REMEMBERTHATWEAREINA•EXPRESSIONSFORFORCEDELTAS:L=1IUÉ S (CLa✗+ ( CLm+2cL0 ) ll)EQUILIBRIUMCONDITION2AVELOCITYPERTURBATIONINDUCESA.nu......................,, § ... g.gg,,,a. , ,....... ,,, 2ANDDIRECTION(a)•LET'SEQUALIZETHETWOEXPRESSIONSOF✗'.1 guts( (xxX+ / [✗we+2C✗☐ ) ie)=Locosdo✗+Lando+DoSisto✗-Dcosdo2--.Iz guts/ c.✗a✗+ I can+zcxo ) ie)=Locosta✗+1 guts/Cia✗+ I can+2C,o ) ie)Santo+2--l--tDosinXOX-1 guts( (☐a✗+ / Com+ZCDO ) n)Costco2--D •LET'SGROUPTERMSWHICHMULTIPLY✗it guts [✗a✗=Locosto+1Iv02scionShao+DoShao-1 guts [☐✗COSXOa222[✗✗=0THEPEAKOFCDISREACHEDINTHESUPERSONICREGIME,BUTIT'SLOWER1MacroDERIVATIVESWITHRESPECTTOthe•RECALL:we=U=Udo=MV0V0doM0REFERENCEMACH•GenericCf:Cf,= DcfCf=CFM02CF=IcfMo2h(uwo)Mon7Mis[LS[☐L[(µ=CLµ'Mo✗a⑥c☐n=c ☐ ..no[mom=[ mom .MoMMMcrMcr•MCR:WHENTHEAIRCRAFTFEELSLOCALLYTHEFIRSTCONDITIONOFM=I•EXPERIMENTALRESULTSSHOWTHATB.ROADRANGESOFFLIGHTMACH,SUFFICIENTLYLOWERFROMMCR(LM=[☐µ=O'THEVA LU EOFCM6µTA K E SASIMILARBEHAVIOURiCM6µ=0FORSUFFICIENTLYLOWAIRSPEEDS•REMARK:CONSIDERINGTHATWEAREDEAL'NOWITHA2SURFACESCONFIGURATION,WHICHISTYPICALFORTRADITIONALCONFIGURATION'SA12CRAFTS,THISCONSIDERATIONSAREACCEPTABLELOWAIRSPEED'S LONGITUDINALDERIVATIVESCLOT,CM6of / ROTARYDERIVATIVES)•MODELLINGBASEDOFTWO-SURFACESMODELPITCH-RATEPERTURBATION9V0aG✓☐.ACT✗T91×0-✗AÉ)• 2T =9/ ✗o-✗ É ) tant ✗it=✗ two .[ it = Yrat ✗T=zo at9( ✗6-✗ c) THISISTHEONLYCOMPONENTOFOVERALLCLDUETO9V0•SLOPE: CLG =2cL=CL=C=zatzolgo -g.ACT)39C9C9CZU02UOZU0T•Cmo=- cut 1 So - Sail =-ura'9 ( ✗o-✗ at)/So- Sai)V0T•SLOPE:Cmo§=Te c m o= Cmo = Cmo =- 2282TI5G-5AE)Z39C9C9CZU02UOZU0•Cmoof=- 2282T/G6-5AI)Z 0I Chop ☐ f 0FORIC4>0byMITUTUT•TA I LCONTRIBUTIONTO[noISDUETOTHEVERTICALTA I L:f)6=✗"T ( ✗AC-✗ G) .0b-20>☐ dy + zedo.tn/ocly)ydy 5bV0NEGLECTABLEit• Chop =Zeno=-2 Ice -Cda)P / b> clyly > dy zvosbtoPb2Pb0ZU0vv• Chop =-4Ice -Cda) [ Zclyly > dySB2•REMARK:BEING[DXSMALL[no f ☐•REMARK:It☐ CM65 ,