Hey there,

since it happened to me again today, I am starting a discussion on this now.

It's the second time, that my Mavic lost its GPS position and suddenly switched to Atti Mode without any obvious reason or indication. The scaring fact is, that both times it still had 15+ satellites and you can't do anything against it - it just happens. Fortunately it got its position again after about 10 seconds.

The first flight it happened was at dusk, the second flight was at daytime completely cloudless. I did a stick calibration, but didn't calibrate IMU nor compass.

Several other users on this forum are experiencing the same issue.

• http://forum.dji.com/thread-73449-1-1.html "WARNING! - Mavic Pro with Litchi"
• http://forum.dji.com/thread-73526-1-2.html "GPS signal dropped at worst possible moment... nearly lost her"
• http://forum.dji.com/thread-73222-1-3.html "Major issue with my new Mavic (Help DJI-KEN)"
• http://forum.dji.com/thread-71860-1-1.html "GPS lost mid flight (possible geographical problem?)"
• http://forum.dji.com/forum.php?mod=redirect&goto=findpost&ptid=71860&pid=573844&fromuid=419100
• http://forum.dji.com/forum.php?mod=redirect&goto=findpost&ptid=71860&pid=577477&fromuid=419100 (or thread on Mavicpilots.com)
• http://mavicpilots.com/threads/atti-mode-mid-flight-causing-the-mavic-to-almost-crash.1813/page-2#post-26784
  

I can imagine bad consequences if this would happen on less open fields with some wind...

I assume you were flying with the Go App?

Shill Slayer Posted at 2016-11-28 04:22
I assume you were flying with the Go App?

Yes, with GO app. But probably this could be the same issue your friend had. So it doesn't matter if flying with GO or Litchi, the Mavic randomly loses GPS positioning without any reason.

Check your compass values. If the Mavic is getting erroneous data from the compass which conflicts with GPS, it will switch to ATTI mode to prevent a flyaway.
The fix is easy. Find an open grassy field and do a compass dance. Do NOT do compass calibrations at every flyzone as you will highly-likely be capturing a bad compass snapshot.
You should only be doing compass dances in open grassy fields. If you travel 70km (east/west), then find another grassy field near the flight location and compass dance there.

  

fansae63899d Posted at 2016-11-28 06:01
Yes, with GO app. But probably this could be the same issue your friend had. So it doesn't matter i ...

I agree it is an issue with the Mavic.  I just want to confirm so we know it's happening with both Litchi & the Go App.  Thank you.

How did you view those logs from the Mavic?

ThorDar Posted at 2016-11-28 04:53
How did you view those logs from the Mavic?

https://healthydrones.com/

QuanthonyTrang Posted at 2016-11-28 06:08
Check your compass values. If the Mavic is getting erroneous data from the compass which conflicts w ...

Is this compass dance similar to the "forbidden" dance? Cause I know those moves already and I can fine-tune it while waiting for the mavic. The first time has to be perfect, don't want to screw it up. So nervous. I already have a mental picture of the location it's perfect!! Oh wait..it's not. The Calibration is most likely to fail due to the interference of the magnetism that planet earth generates. The Moon!! We have to go to the moon! Does China have space tourism yet? Maybe we can get a Mavic Pro Combo-Combo deal which includes a trip to the moon for compass calibration. Off course the US has to remove all the metal crap they dumped there first and the transformers have to leave the dark side because they are made out of metal too, I hate them (or was it the Nazi's.. not sure). But I don't worry, we have plenty of time before mavic arrives.
Oh..The Mavic! is there metal IN or ON the mavic? This also has to go otherwise the compass will fail, and the GPS. It will decide to fly off and then....the thermal wind will come and devour all mavics on the planet AND the moon.

I have the exact same issue...after troubleshooting with DJI-Ken I have to ship mine back for 'repairs'.  Not sure I want it back bc I will still be afraid the issue hasnt been resolved and it is not safe to fly like that.  Mine drifts substantially when it occurs.

Here is my thread on the topic:
http://forum.dji.com/thread-73222-1-3.html

I had the same issue a while back, video and everything showing exactly what happened: http://forum.dji.com/forum.php?mod=viewthread&tid=71860&

MacIak Posted at 2016-11-28 15:11
Is this compass dance similar to the "forbidden" dance? Cause I know those moves already and I can ...

Obviously pilot error

nils.heidorn Posted at 2016-11-28 09:50
Obviously pilot error

Nope. Obviously it is the dreaded thermal winds responsible for everything bad Mavic

Is dji installing cheap parts in this mavic like compass and gps module?It seems to me that dji needs to step up and address the issues people are having before one drifts into a crowded area and hurts someone.atleast gopro had the guts to do a recall when they had a problem with the karma.DJI cant keep using the excuse that it is interference. I can use the gps and compass on my phone all day long in a big city and never have a problem.If and when mine shows up and has this issue I will have no choice but to notify the consumer product safety commission cause you can bet dji wont take the blame if someone gets hurts due to a flyaway caused by the compass or gps or software.

Mine is the second link in the OP's list - thank you for documenting this.   I just wanted to add that I just flew again, and once again, had the same violent TBE happen.  This time, however, the GPS showed full strength signal (19 sats) until about the fourth or fifth loop - then the normal "satellite position off..." error and ATTI switch happened.

When I got it on the ground, I immediately tried to perform a compass calibration.  At this point, I had only 15% of battery remaining.  It prompted me through the two rotation screens, but it failed EVERY SINGLE TIME.  The first (horizontal) spin turned green, then when I attempted the vertical, it would start blinking red when I finished the 360° turn.  I tried it at least 10 times.  Standing, kneeling, praying... I was in a grassy field, with nothing near me.  I just powered it down, and am charging the batteries.   But whatever has the compass scared, it's also preventing it from calibrating.
ETA: Discovered the red blinking lights following the second (vertical) spin was not a failure of calibration, but rather a return of the LED to their "normal" flashing pattern - which was blinking red because the battery was at 15%.  False alarm.

On a side note, is there a way to have these DJI forums send a notification when there is an update to a thread?

It would be good to also know when you and the others receive your Mavics (dates), because if this was indeed a hardware issue, we can see which batches these Mavics belongs to.

This will also allow us to see whether newer received Mavics have this issue or not, which may well indicate whether it's been fixed or not.

It's possible that switching to Sports mode is causing the TBE/drop to ATTI... See the post over at mavicpilots.com at: http://mavicpilots.com/threads/s ... 8/page-2#post-30253

I would suggest everyone stay off Sports mode for now..

MavicUser Posted at 2016-11-29 21:32
It's possible that switching to Sports mode is causing the TBE/drop to ATTI... See the post over at  ...

I'm hoping DJI-Ken and others will look into this, as the evidence presented in that thread is very interesting and could definitely cause the toilet bowl issues people have been having.

Doubt it. Happened to me twice and neither times did I switch to Sports mode.  Are any of the supposed 8 events in this thread  reported as having switched to Sports mode around when the event occurred? None that I recall.  I am not buying it.

This whole matter suggests to me that DJI didn't really beta test the Mavic [hardware and software] widely enough before it was released.

Luckily for those of us stll waiting for Mavic delivery, there are now thousands of people out there who have paid to be Mavic bug testers.

fansae63899d Posted at 2016-11-28 06:51
https://healthydrones.com/

Great, thanks!

I had this same issue.  I was able to land it in atti mode, but it was a challenge.  I did a chat with DJI support to see what they had to say.  The first thing they asked was if I did a compass calibration before the flight, and I told them I did not. They immediately stated that was definitely the cause of the problem and that you're supposed to do a compass calibration before EVERY flight. I challenged that, but they were adamant about the requirement.

I don't have any intention of calibrating the compass before every flight. It's somewhat worrisome that DJI is using that as a scapegoat for this issue though. Basically, they're saying that if you didn't calibrate the compass before the flight, and the Mavic switches to atti mode, it's pilot error.

There has been an update to this. Please see http://mavicpilots.com/threads/spooky-action-at-a-distance.1978/page-3#post-30944

MavicUser Posted at 2016-11-30 11:32
It's possible that switching to Sports mode is causing the TBE/drop to ATTI... See the post over at  ...

There has been an update to this. Please see http://mavicpilots.com/threads/spooky-action-at-a-distance.1978/page-3#post-30944

BudWalker Posted at 2016-11-30 15:54
There has been an update to this. Please see There has been an update to this. Please see http://m ...

messed up link

Nees Posted at 2016-11-30 23:01
messed up link

I must admit I'm a complete klutz when it comes to posting on this forum. I managed to edit those posts. Is it possible to delete a post?

generaltso Posted at 2016-11-30 06:51
I had this same issue.  I was able to land it in atti mode, but it was a challenge.  I did a chat wi ...

Based on my experiences with DJI's chat support they are pretty useless. Both times I've interacted with them, I explain the problem and everything I've tried to fix the problem....and they ignored what I told them and just proceeded through their troubleshooting manual...asking me to do things I've already done.

Happened to me today. Strong wind, so the drifting was terrible. I have been able to come back and land manually correcting, but it was stressful like hell.

I had a lot of Satellite, but it switched off GPS mode with alert.

If I can find something I did which could have triggered the bug (yes it's definitively not the gps lost):  I was in sport mode, and I was at maybe 30 miles/hour and I was adjusting the camera horizon when the problem started (using the hold of the right back button and the right wheels to adjust horizon).  I did sport mode before, I did horizon adjust before, but both in the same time while moving quick, maybe it was my first time.

My logs if interested:  http://www.phantomhelp.com/LogViewer/8PSJ5I0530L937KWPX9N/#

EDIT: Looking at the logs, I was not going that fast when the issue started: around 3miles/hour

That's how I lost mine. I really hope they have a fix by the time mine is repaired.

MnrgD2hZGN6x Posted at 2016-12-4 06:31
Happened to me today. Strong wind, so the drifting was terrible. I have been able to come back and l ...

Although the number of satellites was adequate throught the flight the gpsHealth dropped from 5 (the max) to 1 at time 785. gpsHealth is a measure of (among other things) vertical and horizontal dilution of precision.

MnrgD2hZGN6x Posted at 2016-12-4 06:31
Happened to me today. Strong wind, so the drifting was terrible. I have been able to come back and l ...

I would really like to get the .DAT for this flight. I think the incident is related to the max elevator in Sport mode immediately preceding the incident. The .DAT will help show this.

I'm a complete klutz when it comes to using this forum (I hang out on MavicPilots). If the pilot is willing to provide the .DAT what's the best way to get it to me?

Here are some instructions about retrieving the .DAT which is on the Mavic, not the tablet.

To retrieve a Mavic .DAT file use DJI Assistant 2 and go to the Flight Record tab. After confirming that it's OK to put the Mavic in Flight Data mode a list containing the recent flights will appear. Select just the Flight Control File of the incident flight and then press Save To Local. Ultimately a file with a name something like DJI_ASSISTANT_EXPORT_FILE[2016-10-27 22-40-28].DAT will be created.

Same problem here......

18+ Sats and then lost GPS and the Mavic switched to ATTI and started running the TBE.

https://1drv.ms/t/s!At7S_45c7Dr--1yFbQrntk2y0Loq


DAT:

https://1drv.ms/u/s!At7S_45c7Dr--14TTtfq7OY9iPkn

Happend to me today to,After take off 17 Sats, 1 min later Lost GPS in open field, agian 1 min later full GPS agian.
In that 1 min it was drifting away lucky it was in LOS

I lookd up in flightlog in healty drones it shows green excellent GPS.
But watching FlighRecord in DJO Go app4, gps did go from full white bars to 1 Red Bar and GPS cound stays 18 thats strange.

BrandonA614 Posted at 2016-12-3 14:43
That's how I lost mine. I really hope they have a fix by the time mine is repaired.

This thread should be renamed " DJIs unsuspecting beta testers lose GPS & faith in customer service....lose lose situation

fansbe8cac99 Posted at 2016-12-4 11:55
Same problem here......

18+ Sats and then lost GPS and the Mavic switched to ATTI and started runni ...

Same here (Germany). Full GPS lost with 16 sats... Luckily, the mavic was close to me and I could manage to get back control after some short time. However, not nice if the Mavic is without control and you are just a passenger. I did stick, IMU and Compass calibration before. Also, newest version of firmware was installed (Mavic and Control). The Log-File of the flight I will upload next week.


Edit: I forgot to mention that my Mavic switched once in around 25m altitude to "landing" mode. Should the automatic landing (activated by pulling full down trottle stick) just get activated in the last few meters? Could it be a sensor error? When I am looking close to the downfacing visual sensor it seems like that one of both sensors has some transparent sticker rests on the lens which i can´t remove (i tried but no way...)

Sadly this is why I didn't even open my Mavic when it arrived, I just took some pictures of it and listed it on eBay. There have been way too many issues reported, and I have no plans on spending 1300.00 to become a secret beta tester for DJI with zero support.

fansbe8cac99 Posted at 2016-12-4 18:55
Same problem here......

18+ Sats and then lost GPS and the Mavic switched to ATTI and started runni ...

The number of satellites was adequate throught the flight but there several intervals where gpsHealth dropped from 5 ( the max) to 1. This was the cause of the GPS issue.
There were a total of 5 intervals where gpsHealth dopped to 1. The first two caused a switch to ATTI from GPS_ATTI.

Any chance you can provide the .DAT for this flight?

I had a same problem. I was flying around not far away. (45m high, 30m horizontal), and pressed "go home"
button. He turned to me, passed me, in 3 seconds while it was still in my range of view, it notified some problems with GPS, then it switched to ATTI mode and canceled "go home" commmand. Ive lost visional contact in 10 seconds, while it was drifting fast, i tried to locate it, but in approx 1 minute picture transmission finishes and in some one more minute it was lost. Checking last video on my phone, i found that place (if was more then 800m from me.). I arrived there and a remote controller connected to that, i turned the camera on, and understood that it is on the tree. 20m above the ground. It was a very difficult operation to take that from there, but i did it. I thought what once it lost signal with remote controller with no having active GPS, it was trying to land there. But when i checked the video, i understand how it was.
1. It lost gps signal
2. with wind it drifted far away from me (800m) before losing remote controller signal
3. after that it continued drifting away and it reached the river, that was approx 600-700
after it lost remote controller connection.
4. On the middle of river he turned back and drifted approximately to the place where the signal of remote was lost.
5. And then it catches to the tree.

questions:
1. Why it crached to the tree? All sensors were turned on and active!!!
2. Why having no GPS he didn't try to land on the place where signal with remote was lost, but it continued flying away?
3. somebody knows, if he understand what is water, and that it's not better to land there?
4. I am a beginner and i am lucky that i found it on the tree, that he returned there, but not landed to the river.
5. when he begin going back, it should have find GPS signal, and seems to be begin his way home. But why he changed his attitude (lower that safe attitude), and as result crashed to the tree?!

I thought it was supposed to have more TX range than 800m??
So many reported issues yet it's so darn quiet from DJI side. with thousand and thousands of beta testers you'd expect some more optput. You people (dji) are so disrespectful.
Did your parents teach you this or is it just company policy to treat (well) paying customers like crepe? (please notice I have refrained from using vulgar language)

here is a link to my flight. But it is only the part of flight, from RC logs. I can not take logs from aircraft, because Assistant 2 don't work properly with OS X Sierra. A piece of shit.

MacIak Posted at 2016-12-5 02:09
I thought it was supposed to have more TX range than 800m??
So many reported issues yet it's so dar ...

May be it was only 800m because of forest and not high attitude (50m), there was a little windy and i was afraid to go higher.... and that is good, because it drifted away very fast once i've lost control because of wind. On the groud it was 6-7m/s, but on 50m i think it was twiced..