Hi ,
This Saturday I was at the field to fly my new U CAN Do 3D .50 airplane from Greate Planes. Because it was the first flight I fly with small speed, always the throttle was below 50%. For two or three times the elevator goes to flutter.
I am very confused because the speed was very low, engine running at 25% throttle in that moment.

I will give you some specs about the plane.
It is the U Can Do 3D from Greate Planes (1480 wing span) with an OS .50 Sx ringed engine. The prop is Master Airscrew 11x5 G/F Nylon Propeller.
The elevator is drived by 2 Futaba 9001 coreless servos, one for each half of the elevator. I used the original push-rods from the kit (they are 180mm long and 2mm in diameter). I will try to attach a picture.