Well
the first thing i did was i put a strip of 1/8 ply on the trailing side of the retract gear which has definately made a difference. I also moved the battery about three inches back, so now it sits right next to the throttle servo.

I have both the chipmunks one goldberg and one world models both are great flyers.

How much weight did you add at the tail gear. I dot want to mess up the CG as it flies great in the air.

Zain