Introduction to Aircraft Structural Analysis (Elsevier Aerospace Engineering)

13.2 Symmetric Maneuver Loads 389

levelflightcase.TheenginethrustTisnolongerdirectlyrelatedtothedragD,asthelatterchanges
during the maneuver. Generally, the thrust is regarded as remaining constant and equal to the value
appropriatetoconditionsbeforethemaneuverbegan.

Example 13.3
ThecurvesCD,α,andCM,CGforalightaircraftareshowninFig.13.8(a).Theaircraftweightis8000N,
itswingarea14.5m^2 ,anditsmeanchord1.35m.Determinethelift,drag,tailload,andforwardinertia
forceforasymmetricmaneuvercorrespondington=4.5andaspeedof60m/s.Assumethatengine-
offconditionsapplyandthattheairdensityis1.223kg/m^3 .Figure13.8(b)showstherelevantaircraft
dimensions.

Fig.13.8

(a)CD,α,CM,CG−CLcurves for Example 13.3; (b) geometry of Example 13.3.