Wachtberger Posted at 2018-5-9 07:09
To me it is quite obvious that your GPS link was too weak. Normally a minimum of 11 satellites (better more) are required for a stable GPS link. Another indication for that is the fact that there is no map shown above the flight record. Thus my assumption is that different from what is stated in the flightrecord your MA actually was in ATTI mode and was drifted by wind at take off.

The flight record is shown, it is just a very limited distance of travel.

Look for small green glob right below Avantagarde.   Avantagarde is between Cowboy Bar by the Taste and Axa Affin Life Insurance Agency.

The flight logs show Latitude and Longitude barely change.  Latitude by 0.000008, and Longitude by 0.000014.

Sorry to hear the crash, Felix. I suggest sending the drone in for an overall check if needed, we will also help to make data analysis for this crash since the drone is under warranty to find out the reason for the crash. Please kindly contact our support on the following page to start a case: http://www.dji.com/support

I ve had a somehow similar impact due to pilot error in ATTI mode. I thought the drone would be badly damaged, but I did inspect every millimeter of it and other than a very minor scratch and 2 broken props all was good. Having read a lot of cases were the drone "falls out of the sky for no reasons" I was skeptical to fly far away and push it too much so I did quiet a few flight test and all worked well. Flown 9 flights and 19 km with no issues since... Good luck with your mavic

Landbo Posted at 2018-5-9 15:39
The OP needs to replay his flight log in DJI GO 4 to see what signal quality they had. Phantomhelp doesn't report it.

That's right, we can not see what DJIGO4 shows in Phantomhelp. But do you have an explanation of why the groundspeed is 2.4 mph from the moment the engines is turning  on ?

All I can say here is if the system status was green at takeoff then this is yet another bug in DJI's software. Anyway, DJI must take care of all these software bugs ASAP, there are many of them besides this conjecture.

asaw Posted at 2018-5-10 02:51
All I can say here is if the system status was green at takeoff then this is yet another bug in DJI's software. Anyway, DJI must take care of all these software bugs ASAP, there are many of them besides this conjecture.

We fully agree. DJI's software is a disaster sometimes with their users as beta testers.

Regards Leif.

Same thing happened to me, with zero metal around. Was told the same thing by all the same people in your thread..... Too much metal, but no metal was around. Not a good enough sat signal even though records show strong signal. Problem lies with DJI and their firmware, software and hardware. Too many people with the same exact problems.

GDL Posted at 2018-5-9 17:37
It’s recommended by DJI to calibrate the IMU after upgrade firmware. That maybe why issues occur on MA after upgrade because IMU not calibrate.

Can you please pinpoint where does DJI recommend to calibrate IMU/compass/etc after firmware? All I recall that DJI states only to calibrate if there is a problem or software asks you to do so...

METROID Posted at 2018-5-10 09:01
Can you please pinpoint where does DJI recommend to calibrate IMU/compass/etc after firmware? All I recall that DJI states only to calibrate if there is a problem or software asks you to do so...

There is nowhere it’s another urban myth that continues to spread, no need to calibrate compass or IMU after new firmware.

hallmark007 Posted at 2018-5-9 13:09
Sorry about previous post, I thought 1m was 1 mile but now realize it was 1 metre, this is almost certainly a problem putting aircraft very close to what is a big hunk of metal causing compass heading to move because of magnetic interference coming from the car, you really should be taking off 10 metres from any metal objects and not on concrete which is likely to contain rebar.
Your app will not always warn you of compass problems in these situations.

Thank you for your informed assessment and also explaining that GPS was not an issue in this case. I admit that I had fully overlooked the car mentioned to be 1 meter away at take off which might explain what has happened. Fortunately the incident ended with very limited damage.
P.S. Nevertheless, I shall stick to my policy to never take off with less than 11 satellites.

Wachtberger Posted at 2018-5-10 12:51
Thank you for your informed assessment and also explaining that GPS was not an issue in this case. I admit that I had fully overlooked the car mentioned to be 1 meter away at take off which might explain what has happened. Fortunately the incident ended with very limited damage.
P.S. Nevertheless, I shall stick to my policy to never take off with less than 11 satellites.

I think that’s good advice.

Has anyone considered that the VPS could have picked up blown off debris and tried to follow it?

One thought I will offer up on possibility of detecting magnetic interference prior to take off.

Aim nose of drone at one of compass points (North, East, South, or West) indicated by GO-4 drone on map.
To help you stay in alignment with drone, and aim your smartdevice, try  picking out an object in front of drone that lays at same compass point you aimed drone  at.

With your Smartdevice near drone, but not close enough to cause interference, align top of Smartdevice so it points same direction as nose of drone, and object in front of drone.
If GO-4 compass and drone on map are noticeably different, then there is a chance that there is magnetic interference.  Move drone to another location and repeat.

Back away from drone 10 to 20 feet, staying in alinment with nose of drone and object you picked out.  Ensure top of Smartdevice again points towards nose of drone.
If GO-4 compass and drone on map noticeably deviate, then there is a chance that there is magnetic interference.  Move drone to different area and repeat.

felixlim Posted at 2018-5-10 18:26
Has anyone considered that the VPS could have picked up blown off debris and tried to follow it?

Could be drone's VPS was confused.
Be interesting to recreate what happened, but this time use a large landing pad as take off point.  

https://youtu.be/-jc8bVbUEGQ

Refer to the above video. I think flown debris is indeed a potential for out of control aircraft.

I clean the takeoff place as much as possible. Small rocks or sand blowup can damage the aircraft. Also put a pad on if need to avoid dust blowup.

felixlim Posted at 2018-5-10 18:26
Has anyone considered that the VPS could have picked up blown off debris and tried to follow it?

It seems strange that the simple fact that you took off within 1 metre of a car and drone reacted in a way that is conducive to compass problems that you would simply dismiss this .

Theory could leaf have blocked VPs , that one is very simple if you took off with gps lock then you could also have switched off VPS and your aircraft would not have moved because of gps lock and if leaf had got tangled with motor we would have seen motor obstructed warning.

If you think it’s ok to take off so close to a car then I’m afraid you are on a slippery slope, I will leave you a video below watch it and you might learn why you should not take off around any potential magnetic interference.

You could also send your logs to dji to clear up the matter.

hallmark007 Posted at 2018-5-11 02:21
It seems strange that the simple fact that you took off within 1 metre of a car and drone reacted in a way that is conducive to compass problems that you would simply dismiss this .

Theory could leaf have blocked VPs , that one is very simple if you took off with gps lock then you could also have switched off VPS and your aircraft would not have moved because of gps lock and if leaf had got tangled with motor we would have seen motor obstructed warning.

Very nice video!! Thanks for sharing. Especially the part 3 of this video explains a lot of behaviours around!