AC3.5.4 EKF Error - Land Mode initiated

ArduCopter Copter 3.5
1

I was a minute or so into the flight when I lost control of the aircraft, and regained control by changing to Stabilize mode. Log indicates I had an EKF error at 17,327 which caused a fail safe into Land mode.

Hexa - 17" props & KDE motors running Cube and dual HERE GPS units.

Any insight as to the error would be appreciated. BIN attached.

Thanks,
Rich

https://drive.google.com/open?id=1NrktU_3BpAO-YU_3SKrDZvGjAZuYLpQR

2

way too much vibrations, and sensor clipping, also it’s vibration profile kind of changed during the logged time.
Screw it properly together and balance the props.
-then monitor vibrations next time you have it flying.