I recently crashed and the damage was quite extensive. After putting everything back togeather again, when I get it up to speed, the tail does a voilent spin. The controls work fine before starting the motor, the gyro reacts correctly when I hold the helicopter and move the tail. Could the gears be striped in the servo?, and if so can they be repaired or do I have to replace? The crash was a pretty hard boom strike.

The servo gear set could be striped but you should be able to fell the bad gears by moving the servo through range of motion in power off state. If gears are bad they can be repaired by sending it to the radio mfr.

I just moved the servo through the full range and I could tell nothing. It is a digital servo, and I don't here any gears at all. Maybe I have something else going on.

Just open it and look, being careful to note the layout of the gear train. If you find even 1 broken tooth (look hard, very small) buy a new gearset.

Elmo Te

Elmo Te:

Thanks for the tip. I have another digital servo, so I am going to swap it out before I take the bad one apart.