I've been given a remote controlled chopper (very cheap thing) and I seem to recall there were a few on here with some knowledge about such things.
The bleedin' thing just spins in crazy anticlockwise circles and won't take off. There's a 'Trim' control to stop it doing this, but it makes no difference. It has two lots of articulated blades and a bar with weights at either end above the blades.
So. Back to the shop or user error?