Introduction to Aircraft Structural Analysis (Elsevier Aerospace Engineering)

402 CHAPTER 13 Airframe Loads

Fig. P.13.7

At18300m

ρ=0.116kg/m^3

Ans. P=267852N, P=36257N, L=271931N,n=1.19.

P.13.8 Anaircraftofallupweight145000Nhaswingsofarea50m^2 andmeanchord2.5m.Forthewholeaircraft
CD=0.021+0.041C^2 L,forthewingsdCL/dα=4.8,forthetailplaneofarea9.0m^2 ,dCL,T/dα=2.2allowingfor
theeffectsofdownwash,andthepitchingmomentcoefficientabouttheaerodynamiccenter(ofcompleteaircraft
lesstailplane)basedonwingareaisCM,0=−0.032.GeometricdataaregiveninFig.P.13.8.
Duringasteadyglidewithzerothrustat250m/sEASinwhichCL=0.08,theaircraftmeetsadowngustof
equivalent“sharp-edged”speed6m/s.Calculatethetailload,thegustloadfactor,andtheforwardinertiaforce,
ρ 0 =1.223kg/m^3.

Ans. P=−28902N(down),n=−0.64,forwardinertiaforce=40703N.

Fig. P.13.8