Ardu V.3.1.3 crash after touching yaw


could someone else have a look at my log file please? The copter took off in Stabilize, hovered more or less well at 1 meter height (kept in place by throttle, pitch and roll inputs, not super stable). The second I gave it a little yaw one arm dropped like 25° and the quad accelerated hard for 5 meters and crashed into a shed right next to me. The battery flew out of the copter on impact, so the end of the log is also the end of the flight. If it helps I can post/link the video of the onboard Mobius.

I used the APM Flight Log Analyser V1.0.3.6 and it says that RTL was activated and some GPS glitches happened. But the copter did not rise to 10 meters as configured - just accelerated as hard as it could into that wall. Also it did not flip or crash totally uncontrolled, instead I had the impression that the arm dipped and then stayed at that angle while accelerating, as if it wanted that course - but RTL at 1 meter?

The copter had crashed previously (somewhere else a few weeks back) and the GPS ripped off, I had to resolder the backup-battery. Perhaps it was damaged… I’m using the HK Pilot 2.5 clone and have replaced the 3.3V regulator. Following the instructions given here: I just checked and the new regulator is still working fine.

Thanks for your help!


And here is the video:

A false-positive geofence failsafe happened.

I saw that in the log too but didn’t believe it because the copter did not rise before accelerating sideways. But I did change the RTL-height… perhaps to 1 meter instead of 10 meters? I think this is in the log too, or not?

Just checked: RTL_ALT was set to 1000. That’s in cm meaning 10 meters not 1.

I’ve deactivated the geo fence for now as it seems much more dangerous than helpful. What’s the logic with this “safety” feature? There’s a GPS glitch and without warning the copter speeds away? And at head height?? Is there any other way to explain this? As I said before: It looked a lot like controlled flight - without that shed it would have gone further.

In the meantime I’ve switched to Pixhawk and a newer GPS, but as far as I know it’s the same software (plus half a year of updates).

Thanks for any input. This stuff makes me really nervous when I’m flying. Basically I can’t even go to a park with it as long as it’s not completely deserted.

Well, these days we have glitch detection. Flyaways due to false-positive geofence trips are very rare.