曝光臺 注意防騙
網曝天貓店富美金盛家居專營店坑蒙拐騙欺詐消費者
For simplicity, we ignore thrust variations during the disturbance. Suppose the air-
craftis disturbed in forward speed. We have U - Uo + AU, so that au ='aAU.
Then,
aAF, aFi aAD aD
aAU - aAU = -aAU = -au (4.428)
_ a(;:pU2scD)
au
= -pUSCD - gpU2Saacju
(4.429)
(4.430)
With U ~ Uo, we have
a Fx D
u a~U~ = -p Uo SCD - 2p Uo2S U(., :. ) (4.431)
With u = AU/Uo and Cx = Fx/~:pUo2S,Eq. (4.431) simplifies to
Cxu - -2CD - CDu (4.432)
Next, let us suppose that the aircraft is disturbed in pitch angle O. Then, from Eq.
(4-427),
a AFx aF
dAO - ~d2 =-W,os0o (4.433)
or
Cx0 - -CL cos0o (4.434)
Next, consider the forces in the Oz direction, we have
Fzo - W cos 0o - Lo = O (4.435)
382 PERFORMANCE, STABILITY, DYNAMICS, AND CONTROL
Fz = Fzo + AFz
- W cos(8o + AO) - L
= w cos(0o + AO) - (Lo + AL)
Proceeding in a similar fashion as before, we can show that
Czu = -2CL - CLu
Czo -. -CL siri 0o
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動力機械和機身手冊2(101)