MA goes ballistic spins hits 90kmph and survives

[jaykay]

Can anyone shed light on this?,
very scary 60 seconds with mavic air (less than one week old)
total loss of control, conditions on the day were reasonably good, light to breezy wind (has been flown in stronger winds with no problems), no traffic, no birds, open space, clear unobstructed line of sight between controller and aircraft at all times. i'll link a video of the incident on youtube and attach the log files.
I've had the drone less than a week, i had one other incident on day 2, Battery discharge from 89% to 0% instantly, luckily managed to navigate at low altitude to safe landing and recovery.

Is it possible to tell from log files what the hell happened? Its as if one of the motors failed.
I've uploaded the log file (95% sure its the correct one)

The MA is very impressive when it works, but have had two near fatal incidents within the first 3 hours of flight,
not very encouraging.

Problem?
Total loss of control 1600m from home 35m above home 95m AGL
Aircraft pitched and rolled out of control at one stage strafing at 90kmph
RTH engaged during incident, no effect, sport mode then engaged, no efffect.

Was unit in a crash?
NO, survived, recovered control after aprox 1 min,

What have you tried so far?
Manual control flight home, changed battery, completed further 2 flights at very close range without incident

What device are you using ( iphone , ipad, Samsung , etc)?
Samsung galaxy a5 wired to ma remote

What firmware are you running ( aircraft, remote controller)?
latest

What Go app version are you using?
v4 latest

Any modification? (if so what)
All Stock

Did you change anything or install any apps? (if so what)
no

Do you have a video or pictures of the problem? (if so post link)

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[Qoncussion]

Paging Dr. @sar104 to the O.R.

Hang tight, help is on the way.

 

[Air Beetle]

Did you update every battery you own if you own more than one? There was a fix in one of the upgrades that fixed a battery issue. Yes, the batteries do have firmware and do get updates (not every time). You have to insert each battery you own and repeat the update. I will bet that this is a firmware issue.

I wish people would post the actual firmware number AND Dji go version number instead of just saying "latest".

 

[jaykay]

Thanks beetle, I only own the drone for 5 days, so the app is only 5 days old, I updated firmware as it requested and now tells me everything is up to date when i launch dji go4
How can i check the firmware number on the batteries?

 

[Air Beetle]

When you insert a different battery, it should pop up the firmware warning. I have learned to do all three batteries before I go fly. You can use the pc tool to verify the version numbers on the Air and controller.Some people have issues doing upgrades in the app

 

[sar104]

Paging Dr. @sar104 to the O.R.

Hang tight, help is on the way.

That was exciting. I'll take a look.

 

[jaykay]

Thanks for helping !
@Air Beetle, is the pc tool "dji assistant 2?"
I have it installed on my pc, i'll plug the ma in and see what i can find.

 

[sar104]

Can anyone shed light on this?,
very scary 60 seconds with mavic air (less than one week old)
total loss of control, conditions on the day were reasonably good, light to breezy wind (has been flown in stronger winds with no problems), no traffic, no birds, open space, clear unobstructed line of sight between controller and aircraft at all times. i'll link a video of the incident on youtube and attach the log files.
I've had the drone less than a week, i had one other incident on day 2, Battery discharge from 89% to 0% instantly, luckily managed to navigate at low altitude to safe landing and recovery.

Is it possible to tell from log files what the **** happened? Its as if one of the motors failed.
I've uploaded the log file (95% sure its the correct one)

The MA is very impressive when it works, but have had two near fatal incidents within the first 3 hours of flight,
not very encouraging.

Problem?
Total loss of control 1600m from home 35m above home 95m AGL
Aircraft pitched and rolled out of control at one stage strafing at 90kmph
RTH engaged during incident, no effect, sport mode then engaged, no efffect.

Was unit in a crash?
NO, survived, recovered control after aprox 1 min,

What have you tried so far?
Manual control flight home, changed battery, completed further 2 flights at very close range without incident

What device are you using ( iphone , ipad, Samsung , etc)?
Samsung galaxy a5 wired to ma remote

What firmware are you running ( aircraft, remote controller)?
latest

What Go app version are you using?
v4 latest

Any modification? (if so what)
All Stock

Did you change anything or install any apps? (if so what)
no

Do you have a video or pictures of the problem? (if so post link)

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For more detailed information, see our cookies page.

Accept third party cookies

That log file is not the one for the flight in your video.

 

[jaykay]

dang it! thanks sar, i'll have a look again, they're not so easy to identitfy

 

[sar104]

dang it! thanks sar, i'll have a look again, they're not so easy to identitfy

The files are named with the time and date of the flight, if that is any help.

 

[jaykay]

hmm, i have six records for the day, The problem flight was the first flight, and the record i uploaded was the first record from yesterday :?
How can i inspect the content of the records, they're pretty garbled!

 

[jaykay]

I've checked with dji assistant 2, the mavic air appears in the program but the firmware list does not populate,
the dji go app tells me everything is up to date no matter what battery i have in the ma.

 

[sar104]

hmm, i have six records for the day, The problem flight was the first flight, and the record i uploaded was the first record from yesterday :?
How can i inspect the content of the records, they're pretty garbled!

Follow the instructions here:

DJI Flight Log Viewer - Phantom Help

 

[jaykay]

Thanks again sar,
I've looked at the logs, the one below if definately the culprit,
I dont know what info you can get from it though, doesnt seem to have any parameters from the aircraft itself, (motor rpms, imu state, compass etc?) anyway thanks for having a look,
Any theories on why the aircraft would suddenly take a fit like that?

 

[mad monkey]

Wonder if it got hit by a bird.. It got jittery before flying around

 

[jaykay]

Hi Monkey,
that was my immediate thought while it was happening, There are plenty of birds around and one big buzzard who nests in the next field to where it happened, but the MA returned immaculate, no marks scuffs dents or feathers!!
I reviewed the full res footage carefully afterwards and it doesn't catch a glimpse of anything else airborne. TBH The best case scenario is that it was a bird. My plans for this drone are to film watersports, so a sudden battery fail or death sprial would be... unfortunate.

Its a shame; I was so pumped about the mavic air when ordering, and when i got it,
The first day was brilliant and by day four its tried to kill itself twice...
I'd say my confidence in the product has fallen from 99% to about 51%.

 

[mad monkey]

@sar104 will know what happened according to the drone.. Odds are there will be a map, a detailed explanation, maybe a slide show, charts and graphs. A real professional answer.

 

[sar104]

Thanks again sar,
I've looked at the logs, the one below if definately the culprit,
I dont know what info you can get from it though, doesnt seem to have any parameters from the aircraft itself, (motor rpms, imu state, compass etc?) anyway thanks for having a look,
Any theories on why the aircraft would suddenly take a fit like that?

Yes - that is the correct file. Your video starts at 222 s into the flight. The unusual behavior starts at around 240 s and lasts for around 60 s. The log data clearly show the flight and gimbal motion, with unusual pitch, roll and yaw excursions:



The gimbal yaw is similar to the aircraft yaw with some obvious differences. Comparing with the rudder input, it's apparent that some of the yaw is commanded, but not all of it:



Similarly for the gimbal pitch:



Unfortunately, while the behavior is clear and consistent with the video, I cannot see any cause for it, which suggests that it was entirely under FC control. It was breezy, but not enough to lead to such unstable flight. All other flight parameters appear normal. My suspicion would be an IMU problem, most likely hardware. I suggest that you try an IMU calibration, but the intermittent nature of that problem doesn't suggest that it's a simple calibration issue.

@BudWalker?

 

[RayOZ]

Would trending the motor speeds be able to tell if it was doing that, or it was something external (large wind gust), and motor trying to fight and keep it stable?

 

[sar104]

Would trending the motor speeds be able to tell if it was doing that, or it was something external (large wind gust), and motor trying to fight and keep it stable?

It doesn't look like wind issues - the wind was out of the south at around 10 mph at the altitude in question. But the motor data might reveal more. That obviously needs one of the DAT files (FLY054.DAT).