I would first recomend that you verify that the servos actually move before each flight. Do this with the engine off and on. BEFORE EVERY flight no matter what. Try not to find out about the problems once you are airborne. It could be anything from the RX to the Gyro to the servo. The choice is yours. Try to get it to fail on the ground and then start checking the wires and the gyro. You can verify the RX by plugging the servo directly into the RX, DO NOT fly it this way, but just check iton the ground, in fact I would recomend that you nt run up the engine, and if you do do not try to pull it into a hover.