New N3 on a Q500 'X' frame. 4S, 900kv, 11x4.5 props. Aircraft is stable, predictable, responsive. Flight modes are P/S/G. Testing done in G mode.|
In flight, all motors stop. Not powering down - I mean stopped with braking. This has happened twice now. After repairs I simulated the situation at the workbench, reproducing the problem.
1: Powered on, motors armed and spinning
2: Running without R/P/Y control input, 50% throttle, horizontal on the workbench. No issues, motors run continuously and respond to throttle input.
3: Motors shutdown on command (simulated landing). All is normal so far.
4: Start motors, run for 1 minute on the bench, 50% throttle
5: Pick up the aircraft by hand and move around the room. Motors appear to respond to attitude changes, normally.
6: Pitch > 10 degrees causes instant motor stop.
7: Roll > 10 degrees causes instant motor stop.
Log files are available. YouTu.b.e available.
Is there an attitude threshold that is triggering this behavior? e.g. >10 deg when groundspeed ~zero?
Is there an anomaly with respect to altitude? e.g. I could see this behavior as being correct (motors shutoff at extreme attitudes) if for example the aircraft was at zero altitude when it would be tipping over. But not if it is airborne.
The first crash was from about 3m altitude when the motors stopped and the second at about 8m. Flight conditions, GPS, RSSI were good, batteries fresh, etc.