So i have decided to set up again my Fly Eagle F-100, the jet is one of the first generation jets, no issues what so ever about breaking apart in the air. About five or six years ago i built the plane with ALL new stuff servos, wires, smart fly, Rhino etc. First flight went great with a few clicks of trim needed, second flight was absolutely horrific!!! after a few laps and filling comfortable with the way the plane handle, i started pushing the throttle and this is when Sh@@ hit the fan!!! every time i was about to turn, as soon as i apply elevator to compensate, the plane did not want to come back, turns were so wide that by the time the plane will actually turn i was way out of bounce and so far that i can barely see the airplane, i literally had to trust my fingers just to know which way i needed to move the sticks in order to bring the plane back in sight. When i slow the plane down i regain full control of the elevator like nothing happen. Needles to say after this experience i took the airplane apart and started changing things, wires, elevator servos and batteries. The EXACT something happen again!! fist flight fine, second flight same issue!! i got so frustrated i took the plane apart and used the parts on other airplanes and figure that perhaps the issue was on the actual structure of the airplane. I have decided to put the plane back together again for the third time thinking how can it be a structural issue if it flys slow ok it should fly fast also (unless of coarse it breaks up) maybe i overlooked something. Im getting ready to test fly the airframe again and was just wondering if anyone could make anything out of this issue that i explain. Any advice will be greatly appreciated.