John,

Jason hit it right on the head, but it also sounds like you might have some thrust line issues as well ( up or down thrust ).

The first thing I would do is enter a up line perfectly vertical and perpendicular to the flight line. Once you are headed straight up, take your hands completely off the transmitter and see how long it takes to pitch to the canopy or pitch to the belly. Also take note if it yaws off to the left or right at the same time. These 2 steps will help you make sure the thrust is set properly. After you have done this, then enter a vertical down line from way up high at idle and put in full aileron (and only aileron) and watch the flight path as it comes down. If it wanders or barrel rolls, the you'll probably need some differential as Jason had mentioned.

Bill Higgins Jr.
San Antonio, TX