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Old Feb 01, 2013, 07:44 AM
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United States, SC, Pawleys Island
Joined Jul 2003
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Originally Posted by Aeroplayin View Post
I had trouble with this too until I finally asked Tom what I was doing wrong. He understand it so well and communicates the process so well that I felt like an azz waiting so long to ask him. Correcting with rubber, like powerlines said, is the main thing because it seems so natural to correct the wing rock with ailerons. But what's really happening is that the wings are 'swimming' more than they are simply going up and down.

As one wing stalls first, it experiences more drag, which makes it slower than the other wing, which speeds up from the plane yawing in the direction of the stalled wing. As with a full scale plane, if you use aileron to lift a stalled wing, the down aileron only creates more drag, which can make things worse.

The Rudder applied in one direction will yaw the plane in that direction, speeding up the stalled wing. Over compensation will slow the flying wing and cause it to stall if you're behind in the correction.

So the yawing from side to side speeds up or slows down a wing and causes the faster wing to fly and the slower wing to stall. This is what I mean by swimming as opposed to rocking -- there is forward motion involved, along with the up and down motion.

As far as angle of attack, pulsing the throttle with the elevator back will help increase the AOA and stall both wings. If both wings are stalled at the same time, the rocking goes away.

Forward motion tends to try to level out the plane again and one will will usually start flying first. Using vectored thrust from the prop over the up elevator will keep the tail down so that both wings remain in stall. Good throttle control and a nice big prop disk will help.
Awesome and enlightening explanation!
But I am not sure what the upshot is. Are you saying that rudder is to be used to correct for wing rock? If so, exactly how and when do you apply rudder?
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