Not sure what to check. Any help is appreciated

[CompleteDestruction]

I was find my 130x at the park with a few new batteries Loop's rolls flips just the basic stuff...

I was low and flying inverted from left to right slowly. I gave it negative pitch to climb out, it started to go up and then suddenly slammed down.

Was probably only four feet up when this happened. I was quick on throttle hold and was able to hit it before It hit the ground. There is no obvious damage but something is not right because it makes a horrible sound when I spool it up.. I'm not looking for help with troubleshooting what's broken. I'm trying to figure out what would cause this to happen.

Thoughts?

[Ric66]

Dirty servos? Have you cleaned them lately with deoxit?

[Bhujang]

Old batteries?

[CompleteDestruction]

I only clean then if they "jitter" more than normal..

I have not see them jitter. I will have to power it up and see if i can get it to.. That is a good possibility elevator servo could have caused this...

[CompleteDestruction]

Originally Posted by Bhujang

Old batteries?

It was a 1st flight on this new battery. I cycled it 10 times on the charger to break it in. Increasing the amp each time. From .1A to 1A. The battery is rated to handle a charge rate of 3.6 amps, but I would never charge a battery this smal that high.

[Scream]

I'd say you hit LVC due to the crappy motor connector.

With fresh batteries, more flying juice is going through your system.

Now that it sounds like crap now when you start (high pitched?) I'd suspect that motor connector was your weak link and the cause.

Try replacing with 2mm bullets

[vertico]

Check your pinion. Having a lose pinion can cause exactly this. Loss of power, high pitched noise.

It's highly unlikely it's your connector w new batts plus that doesn't explain the noise. Motor connector on crappy batts ehhh maybe. As long as you have decent batts stock connector is fine.

[CompleteDestruction]

Agreed. Battery connectors may not be the best, but with a brand new battery and a quality battery that that is rated for a 8 C charge and 40c discharge. I don't think I have the issue there.

I'm not sure how to tell if this pinion is slipping on such a tiny motor with it being pressed on. I guess I will have to try to pull it off and if it moves replace the entire motor.

[MiataJohn]

If the pinion is slipping and comes off easily, I would re-install with some green thread lock after cleaning any oil/grease off motor shaft and inside of pinion. Let it cure for 24 hours before handling.

[gunner007]

The high pitched noise is probably coming from one of your servo motors. The gears are not meshing with one another. Sometimes the small servo motor moves up and it's pinion is not engaging with the "white" gear that is attached to the threaded rod .This would cause you to lose that servo and crash. Push the servo motor down until the pinion and gear engage again. Also add a drop of super glue so it doesn't move again. This has happened to me numerous times. You never said where the high pitch noise was coming from. Is it even a high pitch noise or a grinding noise ? If it's a grinding noise, I would say that's a drive train issue.
You may have lost a servo in flight , crashed and now have drive train problem. More info would help.