Had a bit of a scare yesterday. GPS/Compass issue?

[JRodko]

I haven't had my Mavic for that long and I've read the manual quite a few times. I've also spent a lot of time watching videos and flipping through the app settings with the drone grounded. I have about an hour of fly time and have not had any issues until today.

As soon as I started up I was prompted to recalibrate the compass as it was having issue (I'm about 1000km north and 800km west from where I last flew) I believe I calibrated the compass correctly as the status of it right before flight was normal, however I might have dismissed calibration when trying to dismiss the fixed wing flight mode option. Everything looked fine so I took off and did my thing (16 satellites with full strength). Perhaps worth noting also is that I am in an area with no cell reception although I believe this shouldn't matter. I calibrated the compass while roughly 15 feet away from some metal shelving but other than that I saw no cause for disturbance to the nearby magnetic field.

I flew perfectly fine for about 10 minutes including one quick switch to sport mode and back to p (2 minutes). I decided to shut down with about 12 minutes left of flight time so I hit the RTH command on the DJI Go 4 App (galaxy s7). The Mavic was maybe 80? metres away and 60 metres high when I pressed (RTH altitude set to 20).

After a few seconds of beginning the process of returning home I got a notification that GPS signal was low and the controller signaled a switch to ATTI mode. The drone immediately began to drift with the wind and it took me quite a while to bring it back manually (I'm just thankful I had line of sight and the video feed still works).

Flight logs indicated that GPS strength did come back up to full however I was already landing manually. I was flying in a wide open area.

I have opportunities to take this drone places where I am free and clear to max out its range. After this incident however I am hesitant to take it out past 100 meters.

Any ideas or suggestions? I am going to try some more controlled flying tomorrow. I have seen this similar issue posted but have not seen people find a resolve. I believe I am using the most recent firmware.

Here is my flight record. Hope I did that right.

DJI Flight Log Viewer - PhantomHelp.com

 

[Enigma]

hi, the flight log shows magnetic field interference. Perhaps your flight location is throwing off the compass.
RTH is set a bit low, but that should not cause a problem, compasses and smart phone compasses work at ground level.
I would check the compass readings at a significantly different location and see if its out of whack. If it is then i would do another compass calibration.

Its a on going debate when to do a compass calibration. Some say it actually introduces errors, others swear by doing it every time they fly. The only time i do a calibration is when the APP tells me to.

 

[mkp2020]

I think your compass calibration was probably not effective due to magnetic interference. I would go to an area like an open field and do a clean calibration. After that, when you fire up the Mavic pay close attention to the heading of the Mavic on the map to make sure it is pointing in the right direction.

 

[JRodko]

I think your compass calibration was probably not effective due to magnetic interference. I would go to an area like an open field and do a clean calibration. After that, when you fire up the Mavic pay close attention to the heading of the Mavic on the map to make sure it is pointing in the right direction.

I did another compass calibration and things are working quite nicely.

 

[CaliChris]

Yeah I had some issues when I first got it. It seems compass calibration is fairly touchy. I have learned to never do it inside anywhere, too much going on electronically in homes these days. Now, if I need to calibrate, I do it at the park nearby in the middle of a soccer field with all devices far away from the MP. Never had any issues since. Previously I calibrated in the same park, being 20 feet away from a metal picnic table and had issues requiring re-calibration.