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#### Jurgen M

This is usual induced drag diagram.

I have 2 questions:

From Kutta–Joukowski theorem

When effective airflow reduce AoA,

So we must pull yoke and inecrease AoA to keep lift the same, that will increase downwash so Fr will tilt even more back, and induced drag will rise even more.

I have 2 questions:

From Kutta–Joukowski theorem

**Fr**is always perpendicular to effective airflow.**1.**Does it mean for case without effective airflow(zero induced downward velocity), Fr is perpendicular to freestream airflow,so drag is zero?When effective airflow reduce AoA,

**Fr**magnitude must also be reduced(example:Fr at wing is smaller at 6° then on 10°), that mean lift also decrease. What then keep lift constant to satisfy L=Weight?So we must pull yoke and inecrease AoA to keep lift the same, that will increase downwash so Fr will tilt even more back, and induced drag will rise even more.

**2.**Does this theory usualy inculde L=Weight condition or not, so is induced drag shown at pictures is for L=weight condition or without?
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