Crash, collision with tower

Quadcopter, 13 inch props, AUW about 2 kg, Holybro Pixhawk 4 Mini FC, ZED-F9P GPS receiver, 4.03 firmware.
Quad is a research prototype for automated cell tower inspection.

In last flight copter have crashed into tower shortly after mission start. Pilot tries to take cotntrol, but it was too late. Previous flight in same place with almost
same flight plan was absolutely flawless.

The only problems i found in log is a rising divergence between PSC.X,PSC.Y and PSC.TPX,PSC.TPY, wich i can’t explain.

Log from crash fligh
Log from previous flight

Please help.

I can’t see anything obviously wrong up until the crash - mechanical failure maybe? These logs are hard because its difficult to tell the difference between something going wrong and hitting something physically

I found no signs of mechanical failures, only strange position and speed deviations.

About 30 degrees course error


Just out of interest, do you use some kind of RF shielding when flying around the mast and what distance do you fly from the mast?
Could it be that you flew past a microwave antenna and had interference on the ESC’s that is not logged by ArduPilot?

Just throwing out ideas…

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Yes,we have some shielding, but in this case crash was at low altitude, very far from antennas

Probably unrelated but I noticed your Y vibes are a bit high. Have you had a chance to set up the dynamic notch filter yet?

This sequence of events seems to have some significance -

09:46:58 EKF primary changed:1
09:46:58 GPS Glitch
09:47:01 Crash: Disarming
09:46:58 11 2 GPS: GPS GLITCH

How many other successful flights do you have on this aircraft?

Yes, X and Y vibes are little too high, and setting of notch filter was planned.
All that errors appeared about 2 seconds after collision.

68 minutes in air, excluding tuning flights.