Ok I have been flying a Phoenix Giles for a few flights now. I have noticed that the plane has a real bad tendencey to turn as you add elevator.... Like when in a loop it snaps out. It is pretty violent too. I checked all the surfaces and there is no extra play, and the plane is CG correct. Just wondering what causes it and if it can be fixed?

Does this plane have a split elevator? A plane with a split elevator will perform a spiral type loop (wandering off to the side) if the elevator halves are not exactly equal. Snaps on elevator can happen with any plane that has highly effective elevators and is set up with big throws.