Motor stop during flight

Hi, today I fly my VTOL (just in MC mode) to test its behavior. I experienced some bad behavior and analyzing flight logs I can find some strange things but I can’t find out its cause.

First flight:

In the first flight when flying in stabilized mode one motor stopped spinning (see MAIN OUTPUTS) without any apparent reason. Analyzing yaw angular rate I can see a big gap between setpoint and estimated. It happens about 4:20 minute, and it coincides with the motor stopping.

Second flight:

During second flight, same behaviour occurs but this time it leads to a fatal crash. In logs I can see warnings saying (Remaining sensors after failover event 3: Mag #0 priority: 0) but I can’t find what it means.

After all, I want to know if anyones knows what could happen and how to prevent this in future flights.

Additional data:

  • I was using pixhawk cube and internal magnetometers where deactivated to avoid magnetic interference, so only the GPS magnetometer has been used.
  • Airspeed sensor shows negative velocities which I could not interpretate. Maybe in MC mode the propellers can produce any kind of aerodynamic interference with airspeed?

Thank you in advance for your comments.

It looks like your mag just disconnects/stops publishing. Have you checked if the wiring is ok?

Also, I would not disable the internal mags so it can failover to them in that case.
I’m not sure though why the thrust suddenly drops to 0, that’s certainly not expected :thinking: