Average Blade Element Lift Coefficient

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In Chapter 1 it was shown that if each blade element operated at the same lift coefficient, ~ch a relationship with Ct/g could be established that helped give a feeling for how close the rotor was to stall:

A similar calculation can be made in forward flight, although it must be admitted that the usefulness is somewhat limited considering that in forward flight the stall is localized on the retreating side. Let

Т = —[П f * – U2T7t сігіщ

2" J, l 2

Подпись: or

Cr/a = — Г" [‘ Vd — iy

then

Подпись: CT/a-4 l+-p’ 6 2