FMS T-28 1400 mm abrupt pitch upward maiden flight

[Bill]

In the Motion RC reviews section for the FMS T-28 1400 mm, Ronald Gray describes his maiden flight with abrupt upward pitch after takeoff and loss of control. The same thing happened to me. Full down elevator after the upward pitch was not enough to level the plane. Decrease of the throttle added a little control, enough to bring it in for a hard landing with the wind (I could not risk a full fly around). I had a 3600 battery in the plane, and the CG measured slightly nose heavy with the Great Planes CG device.
Ronald states he thought it may be his receiver, but I do not think so.
The only thing I could find after a very hard landing, was the motor mount revealed a 3 mm loose movement in the vertical orientation. Perhaps at full throttle the pitch of the propeller shifted upward and caused this abrupt upward pitch of the aircraft. I added Gorilla glue to stabilize the motor mount in the fuselage.
Any other ideas from the community? I am shaking in my boots before the next flight.
Bill

[Howieal]

Re: FMS T-28 1400 mm abrupt pitch upward maiden flight

Bill - This T-28 has no bad habits. It can tolerate a pretty wide CG range and still be very manageable. A loose engine mount can certainly cause what you describe. I would have recommended that you first tighten the engine bolts and then fly it and see how it handles inverted. If the CG is correct, you shouldn't need a lot of down to hold level inverted flight. If you do need a lot of down then readjust the motor thrust. In other words, get it trimmed properly before using the Gorilla glue. After the Gorilla, your thrust setting will probably be fixed for good.
I've had my T-28 more than a year - all original. No flaps on takeoff and full flaps on landing.
Relax, it's a great airplane. I use 4s 3700-4000 60C.