Heli shut down mid flight

[CrashNburn420]

My Trex 500 pro shut down mid flight on me today. About 3 minutes into a flight. Sats were still lit up solid and the battery was at 3.95 each cell still. Overall damage is minimal, just one set of servo gears.



I'm looking it over at the field and noticed this. The main gear is way up against the frame and noticeably too high on the pinion. Looks like something broke in the hub. The gear was rubbing on the frame pretty good.

I was doing low tic tocs when it shut off



Maybe it caused an over current?

[KSHeli]

Are the main bearing blocks 2 halves that go around the bearing or are the the kind (upgraded) where you press the bearing in from one side. You may have the bearing block in upside down and the bearing was able to move upwards with the side load of the pinion on the main gear which pushed the bearing out. Or are shims required above the main gear and below the lower bearing block. You have a lot of space between the maing ear and the tail main drive gear.

[CrashNburn420]

It was the one way bearing that caused this. It slipped down into the hub. Might be hard to see in the picture but it's not flush where it should be and that caused this. The one way bearing hub wasn't pressing against the main shaft bearing so the main gear was able to rub.

The Heli has around 500-600 flights on it. Took a while for this to fail. Lately I've been trying to tune out a wobble at high collective passes. All the tuning did nothing so I'm guessing/hoping this was it. Doing a full rebuild on the head, drive train and tail.

[zzyzx_cm]

I only let this happen once before i started securing that bearing.

[JANtoolMAN]

....

[zzyzx_cm]

To be honest it cost me a second set of blades because i thought the one way failed when it was the hub. Green tl is your friend.

I had a similar problem when i was running a mix of 2700 and 3300 packs the former lasted 1 minute less.