I recently flew a 27% YAK 54 (great planes). I set up my plane with a Fuji 43 cc gas, with a 20x10 zinger prop, hobbico cs-70 metal gear high torque servos.
The first flight went very well. After a couple flights I started to try higher speed upon trying a pass at half throttle the plane experienced a sevre wing flutter and Ilost complete control of the plane and it crashed.
Some of my friends with 30 years experience in the hobby could not believe the violent action from the wing.
All contol surfaces were set to the manufactures spec and the plane was inspected by club members with experience in large aircraft. All club members agreed that the plane was throughly built.
Any input on this issue would be greatly appreciated.