STEVENS / LEWIS [1] Explain the following:
<< The equations of motion, derived in Chapter 1 are driven by the aerodynamic forces and moments acting on the complete rigid aircraft.
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The aerodynamic forces and moments on an aircraft are produced by the relative motion with respect to the airflow.... [this brings the aerodynamic angles alpha and beta into he scene ]....the aerodynamic forces and moments are also dependet on angular rates....>>.p61
<< The forces and moments acting on th complete aircraft are defined in terms of dimensionless aerodynamic coefficients in the same manner as for the airfoil section...
Drag D = q S C_D
Lift L = q S C_L
Sideforce Y = q S C_Y
Rolling Moment l = q S b C_l
Pitching Moment M = q S c C_M
Yawing Moment N = q S b C_N
where
q = free-stream dynamic pressure
S = wing Reference aera
b = wing span
c = wing mean geometric chord >> p 65
<< Because of the complicated functional dependence of the aerodynamic coefficients, each "total" coefficient is modeled as a sum of components that are , individually functions of fewer variables.>> p66
<< The "total" aerodynamic coefficients. ..are usually expressed as a baseline component, plus incremental or correction terms which we indicate by the symbol DELTA. The baseline component is primarily a function of alpha, beta, and Mach number. Mach dependence can be removed from the baseline components and treated as correction term in case of data for subsonic speeds [ 4xx tables in .air file ?] >>
After considering the origin of rate -dependent components and how they are modeled, the authors evolve the socalled "Component Buildup" >>
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