Hello,
Last version (.400)


At 2:30 flight time, Mavic Air partially stops responding to the remote control, moving to the left. A few seconds later, it begins to spin and fall to the ground, in total about 30 meters. At that moment a message of "strong interference" appeared. After activating the RTH, I was able to recover it.

I have uploaded screen record of DJI GO4 on youtube in this link:


SD Card video on

I attached flight record, and I uploaded it on https://app.airdata.com/main?share=MHxHBe

Edit: http://www.phantomhelp.com/LogViewer/KZ5PGSDAFBZEFIY107MT/Problems start about min 3:50. After 10 seconds I switched to Sport mode, and then, to RTH

Any ideas?

Thanks!

There is very little information on airdata logs can you put up logs using link below might get a clearer picture.

http://www.phantomhelp.com/LogViewer/Upload/

Just click on link below and follow instructions come back here and post your link.

hallmark007 Posted at 2018-5-21 14:15
There is very little information on airdata logs can you put up logs using link below might get a clearer picture.

http://www.phantomhelp.com/LogViewer/Upload/

Thanks for your reply.

I've uploaded on http://www.phantomhelp.com/LogViewer/KZ5PGSDAFBZEFIY107MT/

Problems start about min 3:50. After 10 seconds I switched to Sport mode, and then, to RTH

djiuser_XMcTH3wGy0qN Posted at 2018-5-21 14:21
Thanks for your reply.

I've uploaded on http://www.phantomhelp.com/LogViewer/KZ5PGSDAFBZEFIY107MT/

Yes you can see a drop in altitude coming just after you switched to sport mode, log shows no downward movement of throttle stick, it does look like you were having some gimbal problem which makes it look like it’s the aircraft moving, but I actually think it’s the gimbal, log doesn’t show any strange roll or yaw movements, the strong interference I don’t think was responsible as it came later than both the drop in altitude and first involuntary gimbal movements which could cause this warning to appear.

I think because your log shows very little else it would be wise to contact dji support and get them to have a look at your .dat file. Sorry I can’t be of more help. Good luck.

hallmark007 Posted at 2018-5-21 14:49
Yes you can see a drop in altitude coming just after you switched to sport mode, log shows no downward movement of throttle stick, it does look like you were having some gimbal problem which makes it look like it’s the aircraft moving, but I actually think it’s the gimbal, log doesn’t show any strange roll or yaw movements, the strong interference I don’t think was responsible as it came later than both the drop in altitude and first involuntary gimbal movements which could cause this warning to appear.

I think because your log shows very little else it would be wise to contact dji support and get them to have a look at your .dat file. Sorry I can’t be of more help. Good luck.

In 1/10th of a second from 3:58.8 to 3:58.9, it yawed about 90 degrees from a heading of 131.8 to 40.3.  At this same time it was dropping at a rate of 7.1m/s which far surpasses the maximum document descent speed of 3m/s.  All of this with no indication of stick inputs.

I agree that it might be a good idea to have DJI check out the black box data from the aircraft to see if they can get an idea of why it may have happened.

Have you flown it again since this incident?

KlooGee Posted at 2018-5-21 15:16
In 1/10th of a second from 3:58.8 to 3:58.9, it yawed about 90 degrees from a heading of 131.8 to 40.3.  At this same time it was dropping at a rate of 7.1m/s which far surpasses the maximum document descent speed of 3m/s.  All of this with no indication of stick inputs.

I agree that it might be a good idea to have DJI check out the black box data from the aircraft to see if they can get an idea of why it may have happened.

Your correct there was extreme yaw movement, but having a look at log again it looks like during this yaw movement this may have caused inaccurate altitude measurements as you will see it regained its height when leveled out, so this could have been caused by wind gust as altitude showed 118 metres at 3.58 and returned to 118 at just over 4.01

I immediately think of an attack by a bird since there is no input of the stick. Try to look at the drones surface for scratches.

Regards Leif.

perhaps something in the residential area below is causing the interference?

Landbo Posted at 2018-5-21 16:00
I immediately think of an attack by a bird since there is no input of the stick. Try to look at the drones surface for scratches.

Regards Leif.

The drone has no scratches. It's in perfect condition.

I've reported .DAT file with DJIassistant but I don't have confirmation they received that report.

Bob Brown Posted at 2018-5-21 17:05
perhaps something in the residential area below is causing the interference?

Near the tall building, there is a marine research center of the local university. Maybe I can ask if they have any powerful transmission equipment, or inhibitors ... But this is just my hypothesis.  web: https://ecimat.uvigo.es/en/research.html

KlooGee Posted at 2018-5-21 15:16
In 1/10th of a second from 3:58.8 to 3:58.9, it yawed about 90 degrees from a heading of 131.8 to 40.3.  At this same time it was dropping at a rate of 7.1m/s which far surpasses the maximum document descent speed of 3m/s.  All of this with no indication of stick inputs.

I agree that it might be a good idea to have DJI check out the black box data from the aircraft to see if they can get an idea of why it may have happened.

Yes.
The incident was 2 hours before writing the post. After the incident, I was able to fly without problems in GPS mode and Sport 1 battery mode (17 min). But I never left more than 200 meters and did not fly over the sea again.
Mavic Air did not make me any strange movement at that time.

I had the same thing happened to me yesterday too. I was flying across the river and about 2000ft, suddenly no signal and worst thing RC disconnected. I had flew over there many times and never had that RC disconnected. I thought I lost the Drone. I think there are strong interference near the plant. After that I still burnt 3 batteries flying around the RIVER. Flight log shown nothing significance.



http://www.phantomhelp.com/logviewer/YE4BV7CXTPX1TXWNFMKF/

Hi again,

I have been confirmed that on that island there are research facilities with:
. 2 wireless radio links operating in 5ghz frequency. They are very directional with another point about 5km away.
- 1 Radar HF operating at a frequency of 46Mhz. I do not know the power used.

I discard the radio links because they are very directional and I was never in the path of the link. Also, I was connected to the Mavic Air with 2.4ghz and I did not notice any signal loss.

Can the Radar cause strong/magnetic interference in the drone's compass?

Thanks a lot