Guys

Have some Disappointing support analysis from the DJI SUPPORT today. I noticed one week into getting the Mavic that while flying the mavic. I sometimes experience no GPS or IMU errors. My mavic does not hover sometimes steadily and have been prone to drifting always to the left.  I did as told by the support to recalibrate using DJI assistant both the forward and downward sensors. Did the IMU calibration as well.

Next chance. I went to a open area to test fly it, which to my absolute horror, it crashed

In the first 20mins everything went well. I change to a fresh battery and took off again. I was flying it in a straight line when suddenly I saw the Weak... then "Lost GPS signal" warning on screen. my immediate response was to stop the controller. But to my absolute horror. The mavic fly on and did a sharp left without any inputs from my controller. Being in ATTI I don't expect it to hover still at a spot while there is not input from the remote control. But neither should it be flying by itself. The mavic flew sharply to the left for another 10 sec before crashing. Non of the foward or downward sensors bullsh*t worked for this part to save my Mavic.

This was a defective drone that can do unpredictable things out of a sudden. A week into my exchange with DJI providing them with all the details. They came back with the big answer - Conclusion: Crashed in ATTI mode, no warranty

Really so this is DJI aftercare. It wasn't like I've taken off indoors in ATTI. I was out flying in the open with line of sight of the Mavic. I took off with GPS signal and 5mins later; I lost the GPS and went into ATTI. If this is not a defect why can't they explain THE why it went into ATTI without any valid reason???

Given that we spend so much on a drone and the DJI brand. This is the kinda after-sale support that we get? I might as well get something for a fraction of that price tag.  Absolute disappointment DJI!

How high have You been flying ? I really, really wonder why OPTI-mode does not step in prior to ATTI-mode to stabilize MP ................................

I had a similar accident where the drone suddenly drifted left without input from me. However it says it was good GPS all the time. Just following along on this thread. You are not alone . After downgrading to earlier firmware I have not had this issue. Let us know how things proceed on this.

I have checked your case.
Since you were flying toward the overpass and the GPS signal lost when the drone was under it.
Then the aircraft crashed.
Please refer to the screenshots from the video you provided to us.
Please be more careful when fly in such environment.

bhahah...at night and under the bridge...good job pilot ...I hope also in sport mode

daivatam Posted at 2017-3-13 04:45
bhahah...at night and under the bridge...good job pilot ...I hope also in sport mode

Is there a problem with that?

He had lots of space, no cars around so there should not be any problem? If it properly switched to Atti mode, it should maintain the direction and attitude that he had before loosing gps, influenced by wind.

I cannot imagine quad behaving like this just because it lost GPS signal?

This was unpredictable and the only explanation for me would be Mavic trying to compensate for something? Maybe VPS?

It is asking for problems...yes only in atti without any other problems the quad should be drifting more slowly than a quick turn in one direction...but also the compass was probably affected by the metallic structure  of the bridge and contributed to violent deviation...the gps was not completely lost I think and combined with strong magnetic interference could produce that...the light was low then the vps system was not efficient..
anyway...mavic probably alongside other problems possibly has some internal software conflicts when that stupid auto atti mode enter in action.,...

un hombre Posted at 2017-3-13 05:21
Is there a problem with that?

He had lots of space, no cars around so there should not be any problem? If it properly switched to Atti mode, it should maintain the direction and attitude that he had before loosing gps, influenced by wind.

It cannot maintain neither speed or direction if it does not know where it stands. Under a bridge there will be no gps signal, and at night the VPS will not work. It was sufficient to read the manual to know if you do this fly will be at your own risk.

I was already very careful. As u seen in the screenshot. I kept a safe distance from the beams as well as the height clearance. My path of flight was away from the beams.
Do please educate us on why does my mavic drift sharply left when GPS signal is lost. It's not like I'm flying reckless in this incident. The Mavic just decide to fly its own path. This is not something expected for $1000 drone. And I have seen lots of YouTube videos of the mavic indoors in ATTI mode totally well behave. How do you explain my problem??

Eyesaround Posted at 2017-3-13 06:46
It cannot maintain neither speed or direction if it does not know where it stands. Under a bridge there will be no gps signal, and at night the VPS will not work. It was sufficient to read the manual to know if you do this fly will be at your own risk.

I come from Vision+ and don't have my Mavic yet.

In Vision +, Atti is atti, you loose your gps so the drone maintains attitude only, using the barometer, but is prone to wind.

I presume that in Mavic once you loose GPS it still relies on it's sensors but does it rely on compass reading?

It's interesting to understand the theory and practice before I receive mine. I'd expect Atti to be barometer only, no compass or VPS (I know I can turn this one off but only before flight, or during flight as well)

DJI Mindy Posted at 2017-3-13 03:27
I have checked your case.
Since you were flying toward the overpass and the GPS signal lost when the drone was under it.
Then the aircraft crashed.

Ha! There is always two sides to a story.

But even though, with today's technology available, it would have been nice if they would have put in some gyros to maintain a steady hover in case of GPS loss.

un hombre Posted at 2017-3-13 07:27
I come from Vision+ and don't have my Mavic yet.

In Vision +, Atti is atti, you loose your gps so the drone maintains attitude only, using the barometer, but is prone to wind.

Compass would only tell its orientation, presuming in this case the AC kept its orientation it would still be able to drift sideways.
For the little info we got from the pilot and screenshots posted by Mindy, the pilot was flying in "open space", but he flew the AC directly below a bridge at night at an unknown speed. keep in mind that when it lost GPS it was already moving it might have maintained altitude, but it had now way to know its horizontal position.

Doots Posted at 2017-3-13 07:43
Ha! There is always two sides to a story.

But even though, with today's technology available, it would have been nice if they would have put in some gyros to maintain a steady hover in case of GPS loss.

It has 2 gyros and 2 accelerometers. Still the problem here is it was not hoovering when it lost GPS, it was already moving with unknown possition. What dow we know about wind speed at the time... ?

fans689a8026 Posted at 2017-3-13 07:08
I was already very careful. As u seen in the screenshot. I kept a safe distance from the beams as well as the height clearance. My path of flight was away from the beams.
Do please educate us on why does my mavic drift sharply left when GPS signal is lost. It's not like I'm flying reckless in this incident. The Mavic just decide to fly its own path. This is not something expected for $1000 drone. And I have seen lots of YouTube videos of the mavic indoors in ATTI mode totally well behave. How do you explain my problem??

I have seen lots of YouTube videos of the mavic indoors in ATTI mode

Probably not ATTI mode; more likely OPTI mode, where VPS was enabled and almost certainly used with good lighting (since there was video of it).

On the other hand, your video seems to show that you were flying at night in low-light conditions AND were flying over a road with little in the way of a pattern that VPS could lock onto in order to stabilize your Mavic. And as Eyesaround mentioned, once GPS went out, your Mavic's movement would be influenced not only by whatever momentum it already had but also any wind that was present.

In addition, by your own account you had a full 10 seconds between when you lost GPS and when it actually crashed but you didn't try to use the controls to prevent the crash. That sounds like operator error that would have been covered under Care Refresh (which you apparently don't have) but isn't covered by the warranty. I'm sorry that you crashed your drone, but DJI's position on this seems reasonable to me.

DroneFlying Posted at 2017-3-13 08:07
I have seen lots of YouTube videos of the mavic indoors in ATTI mode

Probably not ATTI mode; more likely OPTI mode, where VPS was enabled and almost certainly used with good lighting (since there was video of it).

Is the full video available?