last updated 5 Sept 2019

| Spark - Product Support - DJI
The User Manual at DJI

Weak GPS goes to ATTI mode https://forum.dji.com/thread-158308-1-1.html
This is what I would do now:
- calibrate IMU. It does not matter if DJI Go says it is normal or not - just do it.

- calibrate compass again but this time do it very slowly (rotate your Spark slowly during calibration). You may want to rotate twice (720 degrees) on both axis.

I will not repeat how important it is to do calibration far away from any potential interference. This does include rocks (I have noticed you are flying in rocky terrain). If rocks contain hematite or magnetite you may be in trouble.

IMU calibration must be done very carefully as well. Level surface, no vibrations etc.

After you have done that, go out and fly. Start from palm launch - just in case rocky ground contains some magnetic or iron ore. Watch for any errors appearing on DJI GO. If they do - land. After several flights analyse your flight records for signs of speed, compass, yaw or GPS issues. If you see any again and you followed my steps with IMU and compass calibration, open ticket with DJI.


DJI flight record analysis
On your phone click menu upper right in DJI App
Menu  >flight record 
 flight record	FlightRecord
 Detailed flight record	MCDatFlightRecords 
 DJI_RECORD 	Video cache   Don't turn off video cache
In drone
   Video   

Flightrecord
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