Outrage BL9088 tail servo is died during the flight

[QYT001]

Today my the most loved tail servo, as it works @8.4V with high speed, Outrage BL9088 died during the flight. I was trying to to turn heli to the left 90 degrees, and stop, but the she didn't and became spinnning counterwise, anyway I was lucky and landed safe.
On the ground I was checking what can be wrong, turned the heli on, and moving rudder stick left/right, but instead the servo was producing some noise and it's not moving or moving a little bit with some noise again, it looks like the gear is stripped or similar. My tail was working fine, no binding and moving is silky smooth.

I didn't open it yet, I'm not sure is it under warranty or not? How to deal with the warranty?

[QYT001]

I opened a case of the servo. It's quite hard to open it by the way, it's so tight, I even did some scratchs on nice red anodizing.
The gear set looks OK w/o any suspicions. While assembling it back I just pulled out and rotated a middle toothed wheel in order to change and utilize another side of gear's teeth.
Some tests shows that it's working so far I hope

It's not clear what was wrong, I need to test it somehow on the heli.

[im4711]

could it be that one of the wires is broken?

[John Cook]

could be pinion coming loose on motor. I wouldn't trust it in the air, at least not w/out ALOT of bench testing