Originally Posted by pghern
What happens if you use the rudder? By design, it's going to roll the plane as well as yaw. Does the gyro then try to correct this? I.E. does it neutralize the roll?
Yes - good point! A gyro on the ailerons will actually neutralize the roll that the rudder causes (which occurs mostly because of the dihedral effect of those raised wing tips).
Roll is a secondary effect of using the rudder. The primary effect is yaw. The yaw causes the raised up wing tip to face the airflow more, and so more lift is generated under that wing tip (it has a greater angle of attack) .... and it goes up, rolling the plane.
As this roll is not the result of aileron input, the gyro will detect the roll and turn the ailerons the other way, to correct it.
The result should be that the rudder's effect should be mainly (or only) yaw.