ORIGINAL: tomfiorentino
I agree with the increased camber in both directions on a symetrical section. But as you know, in order for a symetrical section to create lift in the first place, in needs AOA. And in that instance, aileron deflection still contributes to adverse yaw.
As I am sure you know, at the end of the day, ailerons bank an airplane by increasing lift on one half of the wing relative to the other half. I don't know how lift can increase without also increasing drag. More lift on one sided equals more drag on same side equals a contribution toward adverse yaw. Percentages I don't know.
Do the calculations and you find it is simply two ways of describing the same thing - change of induced drag (drag due to lift) is the same as the change in drag due to rearward and forward inclined lift vectors.
What is is not is drag due to ailerons being deflected into the airflow which is why aileron differential doesn't work, and it is not drag due to change in camber per se otherwise you can't explain why symmetrical sections get adverse yaw.
One myth that keeps popping its ugly head up, and thankfully (though suprisingly) has not yet been put forward in this thread, is that the downgoing aileron is going into higher pressure air and the upgoing into lower pressure air so the form drag from the ailerons is different. It's remarkable how many model fliers cling to that explanation but for good reason since it is often repeated by model magazines etc. Why is it false? The equation for drag is 0.5*air density*V squared*coefficient drag*area. Note that pressure is not in the equation. You can change the pressure up and down and all over the place but every time you run the equation the answer is the same because pressure isn't in it!