Hello all, I'm new to quadcopters and trying to learn as much as I can. So my question is this: After doing all the preflight requirements (warm up , satellite lock , compass calibrate ) and waiting for slow flashing green light , I will have a successful flight with no problems then while landing I will set the copter down very gently and when I chop the throtle the copter wants to skim across the ground at high throtle at about a 45 degree angle draging 2 of the prop gaurds on the ground before finally shutting down?? It doesn't do it ever flight but about 1/2 the time ? TIA John.