I have been flying my Phantom 2 and suddenly in the middle of flight is is like it looses power and drops straight to the ground. As it starts to drop, I try to give to power and it is like it does no good. On occasion if I am not flying too high it will bounce off the ground and then it kind of gains power and it will start flying again. When it is not falling, it will still hover properly. I am stumped on this and am going through propellers like crazy. Can anyone give me some advice on this? Thanks.