Crash during flight q-plane 3.9.7. Help

Could somebody help me analyze my plane log
This was the 10 time I flew this plane,
i was flight about 7 min in 500 radius
during the flight with no command the plane started to turn left in max rate , and get overspeed 31 m/s
and crashed nose down into the ground.

the plane is quad V-tail plane.

I’m afraid there’s a bug, because the incident took place after a few minutes with no command from the ground
I’m flying with the latest version 3.9.7

there is link to the log -

Thank you very much

It looks like you’ve had a loss of RC input.

At 19,5 minutes RCIN.C1…C8 are going down until the impact.
THR_FAILSAFE is disabled.


the rc was nor in use during the flight and was off…
the problem is the plane jest start to dive in left turn ,

Where did the RCIN.C1…4 values come from in minute 4, while you turned in manual mode before switching to Guided-Mode ? If these are inputs from a Joystick, let’s take a look on the tlog-file.