My WM T-34 seems to fly fine, except that I can`t get a straight, round loop out of it. The loop upline starts straight but as it climbs it seems yaw to the left. By the time it pulls through the top it`s on a downline of about 45 degrees. Plane flies straight and level OK ( trims seem OK ). Could it be the rudder trim? What`s the best way to check rudder trim anyway? Any ideas appreciated. Otherwise, I love the plane.