Just to clarify, when the aileron moves downward, lift is increased and the wing is deflected upwards. The increased lift of the wing, increases drag on that wing which produces adverse yaw. So to counter this, aileron controls can be designed to increase the deflection on the downward moving wing aileron more than the upward moving wing - the up-moving aileron goes up 30? while to down moving aileron travels down 20?. See page 134 of Tony Bingelis "The Sport Plane Builder" titled What to do About Adverse Yaw.
Dave McCauley
