Flip and crash in loiter


I experienced a strange crash today. I flew 2 succesful Auto missions, in AltHold and Loiter.
Everything went fine until the last seconds in Loiter.

I flew around my house in Loiter mode and out of the blue the copter accelerated to backleft and
flipped/crashed almost immediately after starting that maneuver.

No mechanical failures. Rotors are good, ESC:s are good, nothing loose.

I can’t find anything wrong in the logs, except Nlon rising to the point when the log ends and
AccZ spiking to 0 .

I think the dataflash got full at the end, but can it be the cause of the crash?
Did APM just stop flying the quad?

Tlog and datalog included.

All ideas/solutions welcomed.

My rig:

APM 2.6 running sw v. 3.1
Tarot Ironman 650 Quad frame
OrangeRX 8 channel reciever with spectrum satellite reciever
SBUS->PPM converter
Spectrum DX8 radio
Hobbywing Platinum 30A ESCs’
T-Motor 360kV motors
15/55 CF rotors
10000mAh 5S GenAce Lipo
3DR 433Mhz telemetry
Ublox GPS / Compass
Tarot 2D gimbal / GoPro

This is probably a power failure. Copter stops logging in the air.