Hi,

I had a strange experience yesterday. My Mavic changed to ATTI mode even though it had something like 16 satellites connected. You can see it from the map. I understand why it makes circles in ATTI mode, probably IMU/compass was calibrated incorrectly or wind was too high, but why does it go to ATTI mode if there's 16+ satellites? That makes me nervous. DJI, do you have any idea?

If you tell me to export flight data, then please help me here first, I haven't got an answer from you yet:
http://forum.dji.com/thread-79342-1-1.html

Thanks!

I lost mine like this yestarday...
I'm desperate just had it for like 5 days...

The number of satellites does not say how good or bad the GPS signal is. This is shown by the GPS icon itself. It shows some bars that tell you the quality of signal.

To check what the bar looked like during your flight:

• Start the DJO Go 4 app on your phone
• In the bottom left corner there is a compass icon with thet text "disconnected" below. Tap on the compass icon.
• You will see your flight profile and at the bottom the last flight.
• Tap the flight and a list of flights is shown.
• Pick the flight with the troubles and play it back.
• You will see at the top the GPS icon and how it changed during the flight.
• If you have a look at the icon, you can see the number 16 probably. And you can see the icon itself with the bars.
  

If you want, you can post a screenshot here for further discussions.

Dronoob Posted at 2017-1-29 11:16
The number of satellites does not say how good or bad the GPS signal is. This is shown by the GPS icon itself. It shows some bars that tell you the quality of signal.

To check what the bar looked like during your flight:

Hi, thank you for the precise steps to replay the footage!
I uploaded the video. As you can see, it has full bars, after it has been drifing for some time, it reports about GPS loss. What do you think about it?

That video is just insane!!
Did it get stuck in a funnel cloud ?

I am a but surprised how quickly it goes from a strong signal to a lost signal. At the end of the video you can see how the GPS signal is slowly recovering. Unfortunately, the video stops at that point so that we cannot see if it got "best" signal gain after some time.

There is a thread Mavic loses GPS fix with 15+ satellites [8 reports so far] with some poeple reporting similar issues. I do not know if the GPS signal can be disturbed so strongly that it goes from 100 to 0 in a second. I have to admit, it looks like a bug in the Mavic's firmware.  I would have expected that the GPS signal got weaker before the GPS is completely lost.

I think that DJI should have a closer look into this (when their holidays are over in a few days).

And some advice: Always fly your drones in a way that YOU can get your drone home when something goes wrong.

Dronoob Posted at 2017-1-29 12:18
I am a but surprised how quickly it goes from a strong signal to a lost signal. At the end of the video you can see how the GPS signal is slowly recovering. Unfortunately, the video stops at that point so that we cannot see if it got "best" signal gain after some time.

There is a thread Mavic loses GPS fix with 15+ satellites [8 reports so far] with some poeple reporting similar issues. I do not know if the GPS signal can be disturbed so strongly that it goes from 100 to 0 in a second. I have to admit, it looks like a bug in the Mavic's firmware.  I would have expected that the GPS signal got weaker before the GPS is completely lost.

Here's the ending clip where signal comes back. It goes to 2 bars and then jumps to all bars. After that I bring the drone down as fast as I can.

Maybe the mavic crashing internally and restarting.. The firmware has it fall into atti with no control? That sounds like a reasonable explanation. I saw you input some sticks and it kept right in the toilet bowl..

Programmer at dji knows exactly what this is, I'm sure.

That's pretty scary if you can't control it

You should look at my post also seems very similar to this except mine even stoped recording the flight log and from the DAT files seems like the drone just shut down in the air

I had similar case today. Was flying in windy evening and suddenly went to atti mode. I didn't like it. We have strange weather conditions here at this moment and TV broadcasts has problems. Something to do with clouds etc. Don't know does it have anything to do with it, but I didn't like it. I could take my mavic safely to ground, but it scared me a bit...

What firmware are you running?

Its caused when you fly in sports mode, electromagnetic interference is high. the compass data corrupts and cant intemperate sat/compass data properly,this is why it shows number of satelites but signal low. what is supposed to happen (since firmware 1.300) is ... the mavic should switch to the secondary compass (at the front) which should be correct but for some reason, in your example it isnt switching...

The internal wiring and ESC location are to blame really, but i'm hopeful they can better resolve this issue in firmware - I'd settle for a slower sport mode if it meant that we had rock solid contol throughout all modes.

Can you confirm your firmware version? I'd stay away from sport mode at the moment, it should be fine in normal GPS mode

New here, but I had the same thing happen to me yesterday in some moderate wind. Luckily I could see it and used the distance to get it back safely. Scary for sure. Not my first bird, but still getting used to the Go 4 app and the AC itself. BTW...can someone please help me locate where I can view what version firmware I'm running? I'm having a problem finding it and don't know if the AC needs to be on/connected/ready to fly. Thanks.

Danny-B- Posted at 2017-1-29 16:10
Its caused when you fly in sports mode, electromagnetic interference is high. the compass data corrupts and cant intemperate sat/compass data properly,this is why it shows number of satelites but signal low. what is supposed to happen (since firmware 1.300) is ... the mavic should switch to the secondary compass (at the front) which should be correct but for some reason, in your example it isnt switching...

The internal wiring and ESC location are to blame really, but i'm hopeful they can better resolve this issue in firmware - I'd settle for a slower sport mode if it meant that we had rock solid contol throughout all modes.

Yeah, but it should drop into atti mode right? The toilet bowl with no control is scary. I only read the threads on the tbe, it's never happened to me. I assumed you could still send commands to the bird until the compass recovered. It seems to be some sort of down time- op said 20 seconds no control

The switch in compass while in sports mode is nice. I use sports and never had issue though. I was thinking of taking her apart if it ever happened and straitening out the wiring to the rear motors. If they're twisted, it's going to act like an inductor under load.

Danny-B- Posted at 2017-1-29 16:10
Its caused when you fly in sports mode, electromagnetic interference is high. the compass data corrupts and cant intemperate sat/compass data properly,this is why it shows number of satelites but signal low. what is supposed to happen (since firmware 1.300) is ... the mavic should switch to the secondary compass (at the front) which should be correct but for some reason, in your example it isnt switching...

The internal wiring and ESC location are to blame really, but i'm hopeful they can better resolve this issue in firmware - I'd settle for a slower sport mode if it meant that we had rock solid contol throughout all modes.

Has happened to me twice and I was not in sport mode.

thehippoz Posted at 2017-1-29 18:33
Yeah, but it should drop into atti mode right? The toilet bowl with no control is scary. I only read the threads on the tbe, it's never happened to me. I assumed you could still send commands to the bird until the compass recovered. It seems to be some sort of down time- op said 20 seconds no control

The switch in compass while in sports mode is nice. I use sports and never had issue though. I was thinking of taking her apart if it ever happened and straitening out the wiring to the rear motors. If they're twisted, it's going to act like an inductor under load.

If it cant recover compass data/Sat data yeah it should switch to ATTI, its only using the compass and the Baro at that point, the TBE is usually caused by a bad compass calibration though so you have to make sure that you do the compass calibration correctly.

The fact that the mavic has two compass's should prevent it from going into atti mode when EMI happens, it shouldnt disable both compass's ...

I havnt had the TBE effect either but it did switch to atti mode on me once on an older firmware just after flying in sport mode. I tend not to use sport much at all, i have mini quads to race with, my mavic is for filming only.

Danny-B- Posted at 2017-1-29 19:00
If it cant recover compass data/Sat data yeah it should switch to ATTI, its only using the compass and the Baro at that point, the TBE is usually caused by a bad compass calibration though so you have to make sure that you do the compass calibration correctly.

The fact that the mavic has two compass's should prevent it from going into atti mode when EMI happens, it shouldnt disable both compass's ...

Something satisfying about flying the mavic out to it's waypoint start in sports mode though. Ah well keep flying it in sports whenever I'm out there and see what happens.

On the ground the high on either compass is under 60, usually 20.

Danny-B- Posted at 2017-1-29 16:10
Its caused when you fly in sports mode, electromagnetic interference is high. the compass data corrupts and cant intemperate sat/compass data properly,this is why it shows number of satelites but signal low. what is supposed to happen (since firmware 1.300) is ... the mavic should switch to the secondary compass (at the front) which should be correct but for some reason, in your example it isnt switching...

The internal wiring and ESC location are to blame really, but i'm hopeful they can better resolve this issue in firmware - I'd settle for a slower sport mode if it meant that we had rock solid contol throughout all modes.

That's a good point. I was flying almost 1km in sports mode, full throttle, before it happened. The weather was a bit foggy.
I have version 01.03.0200.

Well to throw a spanner in the works. I flew sports mode for over kilometer yesterday and had zero issues! That's with persistent rain in area and overcast conditions.  I had 19 satellites with full signal next to huge electricity pylons. don't think you can just blame SPORT mode. I tend to agree with the theory that somehow it is rebooting satellite link during flight.

I suffered the same loss of GPS mode today.   Its the first time its happened to me - though due to repairs under warranty  I've only had about 5 long flights with the Mavic.

I was not in sports mode.  However it was windy - though surely that shouldn't matter?

I waited until it had a GPS fix.  Then took off.

About 45 seconds later I get a "Mode changed to Atti" warning!

Here's part of my warning log from Healthy Drones:

        Flight time        Altitude        Home Distance        Type        Notification
A        00m 00s        0.0 ft        0 ft        Mode        Mode changed to Motors_Started
B        00m 00s        0.0 ft        0 ft        Tip        Tips__Taking Off
C        00m 00s        0.0 ft        0 ft        Tip        Home Point Recorded. RTH Altitude: 30M.
D        00m 01s        0.0 ft        0 ft        Mode        Mode changed to AutoTakeoff
E        00m 01s        0.0 ft        0 ft        Tip        Tips__Taking Off
F        00m 03s        3.0 ft        1 ft        Mode        Mode changed to GPS_Atti
G        00m 48s        15.1 ft        390 ft        Mode        Mode changed to Atti
H        00m 48s        15.1 ft        390 ft        Warning        Warning:Satellite Positioning Off. Fly with caution
I        00m 50s        16.1 ft        415 ft        Mode        Mode changed to GPS_Atti
J        01m 01s        15.1 ft        754 ft        Mode        Mode changed to Atti
K        01m 01s        15.1 ft        754 ft        Warning        Warning:Satellite Positioning Off. Fly with caution
L        01m 11s        16.1 ft        1,086 ft        Mode        Mode changed to GPS_Atti
M        01m 26s        14.8 ft        1,171 ft        Mode        Mode changed to Go_Home
N        01m 26s        14.8 ft        1,171 ft        Tip        Tips__Return-to-Home Initiated
O        02m 25s        97.4 ft        709 ft        Mode        Mode changed to GPS_Atti
P        02m 29s        96.1 ft        695 ft        Mode        Mode changed to Atti
Q        02m 29s        96.1 ft        695 ft        Warning        Warning:Satellite Positioning Off. Fly with caution
R        02m 31s        96.1 ft        697 ft        Mode        Mode changed to GPS_Atti


After 2:31 it didn't lose signal again.

I never had anything like this happen in 18 months of using the Phantom 3.   

To be honest I've had more issues and warnings in a few weeks of the Mavic than I had all the  time I owned the Phantom.

Just had the same problem ! Had 15 sats with full signal , took off and lost control straight away ! None of the stick controls worked !! Thankfully there was a tree in the way ( one smashed prop , but thankfully no other damage ) otherwise it was heading off with a full battery !!!

twh1968 Posted at 2017-2-1 02:26
Just had the same problem ! Had 15 sats with full signal , took off and lost control straight away ! None of the stick controls worked !! Thankfully there was a tree in the way ( one smashed prop , but thankfully no other damage ) otherwise it was heading off with a full battery !!!

I suggest you guys to upload the playback video of those flights (DJI Go app saves the whole playback). It might help DJI to debug that issue.
Also I would be happy to see how your drone was exactly acting, maybe we can figure out some similar mistakes we did.

Here I wrote a small tutorial how to export the video.
http://forum.dji.com/forum.php?mod=viewthread&tid=82897

Hi madispuk

I had a look at your video.  Different timings - my issue started less than a minute in to the flight and after 2:30 mins it was fine for the remaining 7 minutes.

Also I was not in sport mode but normal mode.

But what was similar was your had a good GPS signal - 14 satellites.  Then suddenly the signal bar goes red and GPS is lost.  This is what happened to me.

The conditions of my flight - perhaps similar to yours?

1) It was very windy - 20MPH with a few gusts of 30MPH

2) Its hilly where I was flying - I launched half way down a hill and flew away from the hill to flat open moorland.  

3) When I first started I was quite surprised how quickly it picked up GPS from being switched on.  I remember thinking "wow it got GPS quick"

I don't know if any of this applies to your situation?

fans8162eec0 Posted at 2017-2-1 04:33
Hi madispuk

I had a look at your video.  Different timings - my issue started less than a minute in to the flight and after 2:30 mins it was fine for the remaining 7 minutes.

Nothing applies, lol.

1) No wind at all, but lots of fog.
2) Completely flat land.

madispuk Posted at 2017-2-1 04:38
Nothing applies, lol.

1) No wind at all, but lots of fog.

Hmmmm.....

That rules out obvious environmental factors like a hill blocking GPS signal or the wind causing the Mavic to get disoriented.

And I wasn't in sport mode - so that's not a common factor.

Which means its either a faulty drone with hardware issues.

Or a firmware issue.

I'm going to wait and hope its the 2nd one - I can't face sending my Mavic back again right now.

madispuk Posted at 2017-2-1 04:38
Nothing applies, lol.

1) No wind at all, but lots of fog.

Hi.

Fog weakens the signal from the GPS satellite . Thick fog can actually completely eliminate signals. Furthermore, the fact is when GPS satellites see through the fog, it is mainly those just above your head due to the signal has the shortest way through the fog. Even if the receiver sees 6 satellites just above the head in a the signals not much worth as the phase difference signals in between is not very high, it destroys the accuracy.

Hope you understand despite my bad writing  English.

https://en.wikipedia.org/wiki/Global_Positioning_System

Regards Leif.

Landbo Posted at 2017-2-1 05:52
Hi.

Fog weakens the signal from the GPS satellite . Thick fog can actually completely eliminate signals. Furthermore, the fact is when GPS satellites see through the fog, it is mainly those just above your head due to the signal has the shortest way through the fog. Even if the receiver sees 6 satellites just above the head in a the signals not much worth as the phase difference signals in between is not very high, it destroys the accuracy.

But it wasn't foggy?  The sky was clear.

And have flown my DJI Phantom 3 in fog on one occasion without issue.

I really don't think this is a fog issue.

fans8162eec0 Posted at 2017-2-1 06:12
But it wasn't foggy?  The sky was clear.

And have flown my DJI Phantom 3 in fog on one occasion without issue.

I too have had this problem.  Scares the crap out of me, tons of satellites with superhero signal strength....then - bye- bye Mavic.  This is NO GOOD.  I thought Occusync was coming to our rescue to prevent such things, then DJI invents the 'Fly-away Mode'.

I think they sat in a boardroom and said "How many fly-aways would make us a $million/yr", then someone offered the 'fly-away mode'.  

Having looked at your video, it appears that your flight is having difficulty with compass, it seems like compass and gps are on different headings.

Have you calibrated your compass recently, or was there a lot of magnetic interference in the area you were flying.

TBE is caused by compass and gps headings disagree.

Good luck..

It's not a problem with the compass, I can easily fly indoors in ATTI mode. I think the problem is somewhere deeper. There are so many people reporting that they get sudden GPS signal loss and heavy drifting. While the drone is drifting, it's not possible to move it in any direction (maybe a little), total loss of control. Maybe UFO interference if any, I was in the middle of an empty field, no electric lines etc.

fans8162eec0 Posted at 2017-2-1 01:54
I suffered the same loss of GPS mode today.   Its the first time its happened to me - though due to repairs under warranty  I've only had about 5 long flights with the Mavic.

I was not in sports mode.  However it was windy - though surely that shouldn't matter?

Your loss of gps was for less than 1 second ,first time and less than 2 seconds second time, you give no records as to how many sats you had at these times, or how fast the aircraft was going,
Believe me in 30 mph gusts if you loose gps your aircraft will move at the same speed as the wind , and with the wind, and no matter how good a pilot you are trying to recover this would be extremely hard.

At 48 seconds you lost gps and did nothing to avoid this happening again but continued flying at low height , in what you say was 20 mph gusting to 30mph , flying in normal mode which has a speed of almost the same as the wind and add into the pot gust of 30 mph if you hit 30mph head on your Mavic would be going backwards.

Your height was also very low so drifting in an out of gps is quite possible, if you are loosing gps correct thing to do is to raise your height which you never did, until RTH was activated

Your case is very different to the OP's , and looking at your logs and the info you have given , it all looks pretty normal for the way you were flying..
Good luck...

hallmark007 Posted at 2017-2-1 10:17
Your loss of gps was for less than 1 second ,first time and less than 2 seconds second time, you give no records as to how many sats you had at these times, or how fast the aircraft was going,
Believe me in 30 mph gusts if you loose gps your aircraft will move at the same speed as the wind , and with the wind, and no matter how good a pilot you are trying to recover this would be extremely hard.

Ok thanks.   I did have to switch to sports mode to get the drone back to me.   Stick control remained normal so I didn't lose control at any point.

Like you say it might be a one off due to the windy circumstances.   I'll try again when the weather improves and hope this doesn't happen again.  I've also done a full IMU, compass and controller calibration.  

fans8162eec0 Posted at 2017-2-1 11:40
Ok thanks.   I did have to switch to sports mode to get the drone back to me.   Stick control remained normal so I didn't lose control at any point.

Like you say it might be a one off due to the windy circumstances.   I'll try again when the weather improves and hope this doesn't happen again.  I've also done a full IMU, compass and controller calibration.

You should try a flight for about 10 minutes in sport mode and then play it back in the app , you are likely to see loss of gps occurring for split seconds, just a result of everything trying to keep up with the speed being travelled, nothing to worry about..

DEAR DJI:  Almost the exact same thing happene3d to me on Wed! 16 sats locked in and then ALL of a sudden ATTI comes on the warning. It was drifting away before I could turn it around, I tired RTH button and nothing twice! Finally it locked back on to GPS and I hit the RTH button and this time it was able to function and returned to home. This is my 5th DJI drone. Almost lost this investment on my 2nd flight, that is not fair!!   Please fix this!

Well had my mavic for a few days took it out at lunchtime. Clear day bit of wind nothing I haven't flown in before. Got the camera sorted out. Made sure there was gps. Got it up hovered for a little make sure home point is recorded. Hoping to ensure a safe return. Took it straight up I normally do this and hover again just to check the wind. It starts drifting backwards no inputs on the controls. I don't like this hit RTH. Suddenly no gps gone. Went from full gps signal with 16 sats to nothing in a split second. Recovered the drone small damage nothing serious. Don't understand the systems seem bullet proof. Pilot error?

fans0f3a490d Posted at 2017-6-14 07:19
Well had my mavic for a few days took it out at lunchtime. Clear day bit of wind nothing I haven't flown in before. Got the camera sorted out. Made sure there was gps. Got it up hovered for a little make sure home point is recorded. Hoping to ensure a safe return. Took it straight up I normally do this and hover again just to check the wind. It starts drifting backwards no inputs on the controls. I don't like this hit RTH. Suddenly no gps gone. Went from full gps signal with 16 sats to nothing in a split second. Recovered the drone small damage nothing serious. Don't understand the systems seem bullet proof. Pilot error?

Pilot error?

That's hard to say, but it doesn't really sound like it from your description of the events. The best way for us to try to figure out what happened is for you to upload the DAT file for the flight using these instructions. Once you've done that, put the file on DropBox and post a link to it in this thread and someone will analyze it.

Let me start off by saying I'm very new to flying DJI products. I just got a Mavic Pro for Father’s Day and it was the best!  However, I almost had 2 fly aways within the first hours of using it. One I regained control, have no idea how. Just hit some buttons in a panic and rebooted the app and got lucky and regained control just long enough to quickly land it. The second time I could not control anything but it was hovering within reaching distance. I reached up and grabbed it and the blades tried to compensate. I held it down a little reached over and tried to turn it off but it would not power down. I had to pull the battery. I calibrated everything, ensured the GPS was calibrated. Had it in beginner mode so it would not take off unless GPS was good (right?) Prior to losing control it kept saying disconnected in the app but I could control it from the controller after a few minutes trying to reboot the app, I eventually lost control via the controller.  Very scary and makes me want to return it instead of pushing my luck with a 3rd strike fly away of $1300. It is the flymore combo and it did it with 2 separate batteries. I would also like to state I had a few successful flights a few hours before with no problems in the backyard. I went to the front yard to get some pictures and video of the house and this is where I had the 2 close calls.  I have the logs but not sure how or who to send them too for examination. Any help or advice would be greatly appreciated. I'm thinking about returning it and getting a P3 to limit my loss if I have a fly away. I did a lot of reading, made sure to follow all the instructions, pressed the RTH before panicing but nothing worked and it did not respond to anything. I spent hours making sure everyting was setup calibrated etc. before the first launch. I'm not a drone expert, but I have successful experience with other drones such as hubsan.

I'm not sure my issue was identical to what happened to you guys, but I had a fly-away from which I was luckily able to recover.During a flight in Portugal, my app suddenly went dark. I'm not sure if it crashed or if there was some other issue with my phone. The data playback of that flight shows at the very same time a "Weak GPS" warning, plus two more: "Warning: Compass error. Exit P-GPS mode" and "Warning: IMU heading exception (in-flight). Please switch to atti mode if craft behave abnormally (Using)" (sic)
I was too far out to see exactly which way the Mavic was pointing, but I still had connection between the controller and the Mavic. It was just a dot, and I just didn't know which way to fly it (I know - keep it in range etc, etc.). A minute and 16 seconds of panic ensued. I pressed the RTH button to no avail. In retrospect, it's possible that I might not have pressed it long enough. A few seconds later I tried again and the Mavic went into RTH mode and came back to land without further drama.
I had a feeling that my phone had something to do with the issue, and after some research, I learned from DJI support - to my total shock - that the iPhone 7 is not among the supported devices! I don't know if that was the source of the problem, because later I started having connection issues between the phone and the Mavic, where the video and all the data flow would just cut out, even with the bird on the ground. I learned that the little black cable connecting the phone to the controller has been a source of trouble, so I used my Apple cable and connected to the controller's USB port. In the following 9 flights since then, I had no more issues and was able to fly my best flights yet (I'm a newbie). I intend to connect it that way from now on, as I slowly regain confidence. I have to say that I've gotten my heart rate up way higher than I ever expected flying a drone...

fans898b4084 Posted at 2017-6-28 17:05
I'm not sure my issue was identical to what happened to you guys, but I had a fly-away from which I was luckily able to recover.During a flight in Portugal, my app suddenly went dark. I'm not sure if it crashed or if there was some other issue with my phone. The data playback of that flight shows at the very same time a "Weak GPS" warning, plus two more: "Warning: Compass error. Exit P-GPS mode" and "Warning: IMU heading exception (in-flight). Please switch to atti mode if craft behave abnormally (Using)" (sic)
I was too far out to see exactly which way the Mavic was pointing, but I still had connection between the controller and the Mavic. It was just a dot, and I just didn't know which way to fly it (I know - keep it in range etc, etc.). A minute and 16 seconds of panic ensued. I pressed the RTH button to no avail. In retrospect, it's possible that I might not have pressed it long enough. A few seconds later I tried again and the Mavic went into RTH mode and came back to land without further drama.
I had a feeling that my phone had something to do with the issue, and after some research, I learned from DJI support - to my total shock - that the iPhone 7 is not among the supported devices! I don't know if that was the source of the problem, because later I started having connection issues between the phone and the Mavic, where the video and all the data flow would just cut out, even with the bird on the ground. I learned that the little black cable connecting the phone to the controller has been a source of trouble, so I used my Apple cable and connected to the controller's USB port. In the following 9 flights since then, I had no more issues and was able to fly my best flights yet (I'm a newbie). I intend to connect it that way from now on, as I slowly regain confidence. I have to say that I've gotten my heart rate up way higher than I ever expected flying a drone...

The DAT file on your Mavic contains a lot of detail regarding what happened during the flight. If you'd like to access it using these instructions, upload it to DropBox and provide a link to it here someone will take a look and may be able to provide some insight on what happened during that flight.

A simple question really, but I have to ask. When you had these situations, was your phone/tablet in airplane mode? I always use airplane mode on my Huawei Honor 7 (which is not supported I think?) and it works flawlessly. However I once forgot to switch it on and has severe problems with Dji app. I don't know what causes it, but somehow perhaps multitasking (cellular data, cellular info, switching between link towers etc.) is somehow to blame?