LOST all control: Abnormal compass function or GPS signal detected. Aircraft switched to ATTI mode

naturecannon · Jan 13, 2018

Was flying tonight in my regular at home practice/test area, in this area i have never had a problem over the months. I had 5 flights today with zero issue. I Put in a fresh battery for my last flight and lost all control shortly after takeoff. RC wouldn't respond to anything, no sticks, no RTH, NOTHING. It was drifting toward a tree but luckily missed. MP didn't go as far down the block as map shows but far enough for a scare. After a few minutes of thinking all worst case scenarios in my head it finally came back to life, I had RC control again landed and i shut er down for the night.

If GPS is lost which, i have never lost with the MP yet why didn't the RC work so i can control in myself? I had the f550 years ago so not too concerned on taking control myself in ATTI but tonight i didn't even have the opportunity to do that? Was my incident a freak incident? Why didn't the MP Return to home after loosing RC connection, I say lost cause RC had no response. I suppose RTH and RC dint work because it was the MP with issues?

I sure wish there was a switch to allow me to bypass the GPS and take control myself, the MP was helpless in the air tonight .

Did i encounter some freak GPS storm or should i be concerned?

My LOG DJI Flight Log Viewer - PhantomHelp.com

I did a compass calibration about a month ago in the exact same homepoint used tonight.

One last thing, can anyone explain all the yaw errors in the log?

Anthony · Jan 13, 2018

As soon as the Mavic has a compass error or any error that affects heading or hight it can not switch to Auto RTH and once it goes into ATTI it will not go into RTH mode also. I would log a support call with DJI and send them your flight dat file and see what thy come back with but mainly log it so you have a record of this issue with DJI for future reference.

I have had a Mavic for over a year and not had any ATTI events at all. I am on my second Mavic as I had one of the early ones that had the compass interference issue when switching to sports mode but other than that it flew without any issues.

GerdS · Jan 13, 2018

I have no explanation found for the loss of RC control but I am wondering about you VPS altitude which seems to become invalid already at about 10 ft altitude instead of about 30 ft. IS there dirt on the sensors?
In case of compass error and falling into Atti mode it shall be helpfull to yaw the Mavic a few times fully 360°, which shall do an emmergency calibration. Have never tried by myself as my Mavic from 11/2016 has never fallen into Atti mode or displayed compass errors in flight.

In your case I would calibrate the compass, do a further test flight and even if all looks ok I would check again the log file for compass and yaw errors and in case there is any anormality I would send the Mavic to DJI for repair.