So was out flying today and no issues at all. At about 900m from me, 200 meters and 40% battery Suddenly I get a message saying that the god signal has been lost and to fly carefully. No more than 5 seconds later the RC lost connection and I never saw my mavic again.... waited around for 20 minutes forgiving the RTH function would have worked but no luck. The more I think about this the madder I become. Sure it's another story of "I lost my drone" BUT I did nothing wrong and it just lost connnection to gps and the remote and then was never seen again. Is it right that DJI indemnify and say user error?

We might be able to point you in the direction of your lost Mavic if you upload the logs and provide a link using the directions here. Without seeing the logs it's hard to know what happened and how much blame to assign where.

I am happy to upload the logs but it was over water so not sure I'll be able to retrieve it.

fansecaeb8c2 Posted at 2017-4-10 18:00
I am happy to upload the logs but it was over water so not sure I'll be able to retrieve it.

The logs I meant are written to your mobile device when you use the DJI Go 4 app and unless you've uninstalled the app those logs are still there. The web page I provided a link to has links to instructions on accessing the logs from your mobile device.

Here's a pic from the logs just before I lost it. Was showing full gps signal and then dropped to nothing on a clear sunny day...

fansecaeb8c2 Posted at 2017-4-10 18:06
Here's a pic from the logs just before I lost it. Was showing full gps signal and then dropped to nothing on a clear sunny day...

Well, that tells me a little bit but not nearly as much as can be gleaned from the logs. ATTI mode with 19 (?) satellites is certainly unusual. DJI will probably also want to look at your flight information, and will ask you to sync the information on your mobile device with their server.

Will download the logs tomorrow and hopefully this will shed a little more light on it. Thanks

You can see 19 gps (in number) but look at the gps bar, 1 red bar only.
This happen to lot of Mavic, I don't know why.
In this case it was in Atti mode and the wind blow it away, because there was no gps so RTH would not work properly.

fansecaeb8c2 Posted at 2017-4-10 18:06
Here's a pic from the logs just before I lost it. Was showing full gps signal and then dropped to nothing on a clear sunny day...

The loss of GPS signal while maintaining a high number of satellites is a problem that has been reported multiple times. It will subsequently drop into Atti mode where it drifts with the wind and can be lost. There are multiple reports and analysis of this problem on mavicpilots.com that go into great detail , but no definitive cause or solution. DJI has been very quite about this issue.

If you want an external full analysis of what happened you should post it on mavicpilots.com under help. Since you lost the Mavic the full flight log is gone, but the log from the App may be helpful.
The MODS here are also very helpful and may send your  log to DJI engineers, but unfortunately,  I've never heard followup from the engineering group. Perhaps these unfortunate events are a mystery to them also, or maybe  they don't have a solution to offer.

fansecaeb8c2 Posted at 2017-4-10 18:06
Here's a pic from the logs just before I lost it. Was showing full gps signal and then dropped to nothing on a clear sunny day...

Looks like a similar problem to what I had too...lost over water when the Mavic suddenly decided to switch to ATTI mode with 15 satellites.

Sorry to hear about the loss of your drone.
Please sync your flight records from the DJI Go app and send an email to support.us@dji.com with your DJI account email and the date this occurred.
Our engineers will analyze the data and let you know what could have caused the issue.

It looks similar to my story: http://forum.dji.com/thread-91866-1-1.html

But mine dropped to the ground at the same time as it lost signal.

The BATTI problem that used to be common has become pretty much unheard of with the more recent firmware versions, so I'd be curious to know what firmware version you were using.

Regarding the earlier suggestion that you post the logs on MavicPilots, that's your choice but I disagree. I recently made that same recommendation to someone else and he got slammed by people there because he dared send his Mavic back to DJI without first retrieving the DAT files and posting them to that forum. And the fact that he needed a replacement in a hurry for an upcoming trip was deemed an insufficient excuse by his critics. The moderators even wound up having to "clean up" (delete posts from) and lock the thread (prevent further comments), but that was only after people had beaten up on the guy a while.

So post there at your own risk: from what I've seen you're likely to get as much abuse as helpful and friendly advice. Besides, since your aircraft is lost the only thing anyone can analyze is the log data from your mobile device, and there are people on this forum capable of providing feedback that's likely to be just as helpful but without the verbal abuse. And honestly, at the end of the day it's only DJI's evaluation of the logs that's going to really matter, because that's what'll determine whether or not you get a warranty replacement.

Sent the logs across to DJI. how can i post the same log here for review by what i imagine will be a less biased view?

fansecaeb8c2 Posted at 2017-4-11 06:41
Sent the logs across to DJI. how can i post the same log here for review by what i imagine will be a less biased view?

The instructions for it are here.

worked it out
http://www.phantomhelp.com/LogViewer/Y22HVVA3TEW7TLUTFAJL/

Were you flying in sport mode before this happened?
Sorry i've just looked at the logs ... and to answer my question, yes you were, for a while i'll admit, but i am pretty certain this is the issue that makes the mavic drop into atti mode. I've seen this so many times and i'm afraid to say i never use sport mode for this very reason.

They have mentioned over and over again that firmware revisions have corrected the sport mode, electromagnetic interfiernece issue, but i disagree, there is an issue from the posts i see and what makes it worse in this case is that it seems to have disconnected your RC link in the process too ... it seems to loose connection a couple of times in that flight and usually when your going over 30+mph.

fansecaeb8c2 Posted at 2017-4-11 06:41
Sent the logs across to DJI. how can i post the same log here for review by what i imagine will be a less biased view?

how can i post the same log here for review by what i imagine will be a less biased view?

Hopefully that -- and civil responses too.

TLDR; I'm guessing it eventually did try to RTH and crashed into the eastern side of the Goldman Sachs Tower on the way back. The tower is almost 800 feet tall, meaning that even with the extra boost in altitude you gave your Mavic it wouldn't have cleared the building on the return trip.

As Danny mentioned -- and you probably already realized -- it dropped into ATTI mode a couple of times even though you were flying over the middle of the Hudson River with plenty of satellites. And yes, this does seem to be associated with Sport mode and compass problems that can result when using it. Unfortunately, the last time it went into ATTI mode you were heading west and almost behind the Goldman Sachs Tower -- and winds were out of the south that day, which would have resulted in it drifting north, putting it behind the building. Assuming that it eventually recovered from ATTI and was behind the building at that point, it would probably have failed to connect with the controller and would then initiate RTH. And again, with the building being much taller than your Mavic's altitude (and its RTH altitude setting), it probably crashed trying to get back. On the other hand, if it never recovered from ATTI it would have just drifted until it ran out of battery, but that's less likely since you had 37% battery remaining when you lost contact; in every case I've ever heard of, the spontaneous ATTI problem goes away as suddenly as it appears, just as it did earlier in this flight.

So yeah, my personal opinion is that you should have a reasonable shot at DJI taking some responsibility for this because of the spontaneous ATTI mode, but of course that's ultimately going to be their call. If I wanted to play Drone Police I could lecture you on a couple of points, but I'll leave that to others who enjoy it more and are better at it than me. Personally, I don't get much enjoyment from it when somebody's already upset over the loss of a pricey item and I think it discourages others from coming forward to ask for help. The only thing I will say is that 30m is a tad on the low side for an RTH altitude when you're flying around in NYC.

P.S. Out of curiosity, how long had you owned your Mavic? DJI made a hardware change to the Mavic's internals to mitigate the compass-problems-in-Sport-mode a while back, but if yours was a newer Mavic then you already had the new and improved hardware.

DroneFlying Posted at 2017-4-11 02:29
The BATTI problem that used to be common has become pretty much unheard of with the more recent firmware versions, so I'd be curious to know what firmware version you were using.

Regarding the earlier suggestion that you post the logs on MavicPilots, that's your choice but I disagree. I recently made that same recommendation to someone else and he got slammed by people there because he dared send his Mavic back to DJI without first retrieving the DAT files and posting them to that forum. And the fact that he needed a replacement in a hurry for an upcoming trip was deemed an insufficient excuse by his critics. The moderators even wound up having to "clean up" (delete posts from) and lock the thread (prevent further comments), but that was only after people had beaten up on the guy a while.

I was also reading that thread on the Mavic Pilots forum and even though things did get pretty nasty in that one, I honestly don't feel that's characteristic of the forum overall. I'm sure there are a few d-bags in there, but there are also a good number of very helpful and knowledgable people, especially willing to take a look at logs and give an unbiased opinion. Posters also tend to get their logs looked at more quickly and by more people over there. Overall, for log file analysis, I'd still look to Mavic Pilots over this one.

Would you mind posting the serial number of your Mavic? And/or look up the build date here and post it: http://djiserialdecoder.x10host.com/

Jason Lane Posted at 2017-4-11 08:26
I was also reading that thread on the Mavic Pilots forum and even though things did get pretty nasty in that one, I honestly don't feel that's characteristic of the forum overall. I'm sure there are a few d-bags in there, but there are also a good number of very helpful and knowledgable people, especially willing to take a look at logs and give an unbiased opinion. Posters also tend to get their logs looked at more quickly and by more people over there. Overall, for log file analysis, I'd still look to Mavic Pilots over this one.

I honestly don't feel that's characteristic of the forum overall.

It's not as long as you're discussing things like, oh, whether you prefer to fly back manually or use RTH. But from what I've seen, people asking for help with crashes often come away with some severe tire damage.

I'm sure there are a few d-bags in there, but there are also a good number of very helpful and knowledgable people

That's very true. At least a couple of those guys seem to really know what they're talking about and are consistently civil. But there are also a lot of other folks who like to weigh in on these things.

Overall, for log file analysis, I'd still look to Mavic Pilots over this one.

Why don't you start a thread over there with a link to his logs and see how it turns out? Might be an interesting exercise, and the OP wouldn't have to interact with them.

DroneFlying Posted at 2017-4-11 02:29
The BATTI problem that used to be common has become pretty much unheard of with the more recent firmware versions, so I'd be curious to know what firmware version you were using.

Regarding the earlier suggestion that you post the logs on MavicPilots, that's your choice but I disagree. I recently made that same recommendation to someone else and he got slammed by people there because he dared send his Mavic back to DJI without first retrieving the DAT files and posting them to that forum. And the fact that he needed a replacement in a hurry for an upcoming trip was deemed an insufficient excuse by his critics. The moderators even wound up having to "clean up" (delete posts from) and lock the thread (prevent further comments), but that was only after people had beaten up on the guy a while.

Yeah, just lurk there. I don't post anything. There's some cool guys there who know their stuff like logger and budwalker, then have that spock guy he gets a lot of likes because, well he's spock.

The drop to atti is pretty serious. But it was caused from bad compass calibrations by users and the early batches of mavics compounded the problem from what I gather, by creating a lot of emf (especially in sport mode) to the rear motors.

DroneFlying Posted at 2017-4-11 08:39
I honestly don't feel that's characteristic of the forum overall.

It's not as long as you're discussing things like, oh, whether you prefer to fly back manually or use RTH. But from what I've seen, people asking for help with crashes often come away with some severe tire damage.

"Why don't you start a thread over there with a link to his logs and see how it turns out? Might be an interesting exercise, and the OP wouldn't have to interact with them."

I guess I might as well :-) Although I'll ask the OP's permission, first.

fansecaeb8c2 Posted at 2017-4-11 06:41
Sent the logs across to DJI. how can i post the same log here for review by what i imagine will be a less biased view?

As DroneFlying has suggested, I could start a thread about your incident on the Mavic Pilots forum for you, if you'd like.

How about it? Would you like to take up Jason's kind offer to post a link to your flight logs on the MavicPilots forum? For the record, I'm in complete agreement with him that some of the expertise available there is second to none. And it's definitely superior to what I'd claim to be able to offer personally.

Jason that would be great. Many thanks

thehippoz Posted at 2017-4-11 08:51
Yeah, just lurk there. I don't post anything. There's some cool guys there who know their stuff like logger and budwalker, then have that spock guy he gets a lot of likes because, well he's spock.

The drop to atti is pretty serious. But it was caused from bad compass calibrations by users and the early batches of mavics compounded the problem from what I gather, by creating a lot of emf (especially in sport mode) to the rear motors.

Yeah, just lurk there. I don't post anything.

Same here; I just don't consider it worth the grief to participate, but it is a great resource when it comes to searching for information.

There's some cool guys there who know their stuff like logger and budwalker, then have that spock guy he gets a lot of likes because, well he's spock.

DId you catch the thread that started out being about how to defeat the altitude restrictions and turned into a discussion by Budwalker and others about the role of GPS versus barometer in the Mavic? Very good stuff.

The drop to atti is pretty serious. But it was caused from bad compass calibrations by users and the early batches of mavics compounded the problem from what I gather, by creating a lot of emf (especially in sport mode) to the rear motors.

That's what I was thinking too.

DroneFlying Posted at 2017-4-11 09:12
Yeah, just lurk there. I don't post anything.

Same here; I just don't consider it worth the grief to participate, but it is a great resource when it comes to searching for information.

Defeating altitude restrictions xd I bet that was fun. Yeah barometer is height, they put all the sensors on the bottom to make the mavic into a table while close to the ground too. Gps is position. I'll check it out later.

DroneFlying Posted at 2017-4-11 07:34
how can i post the same log here for review by what i imagine will be a less biased view?

Hopefully that -- and civil responses too.

Well said, and very constructive post. I get tired of seeing users being flamed to death for posting their crash info and people trying to deflect any blame towards user error ... if only more people took the time to be as constructive.

As you quite rightly said ... there are a few user issues such as RTH height etc, but i feel that the main issue in this case was the drop to atti mode, i wonder what the outcome will be.

fansecaeb8c2 Posted at 2017-4-11 09:13
Jason that would be great. Many thanks

No problem. Let's see what they say. There's a limit to what can be seen without the .dat file from the Mavic itself, but maybe they can find some clues in the RC's log.

DroneFlying Posted at 2017-4-11 07:34
how can i post the same log here for review by what i imagine will be a less biased view?

Hopefully that -- and civil responses too.

Good analysis.

Jason Lane Posted at 2017-4-11 10:08
No problem. Let's see what they say. There's a limit to what can be seen without the .dat file from the Mavic itself, but maybe they can find some clues in the RC's log.

Thanks for posting that, Jason. I have to admit to being a little disappointed that it was posted in Mavic Pro Help, because that's sort of a "back street" on MavicPilots and might not get the same type and degree of scrutiny that most posts of its kind do there, but at least Mike and Robby have noticed it. I did see that you had also posted a link back to this thread (per Mike's request) but that post is now deleted.

So far, though, all we've gotten is guesswork about this being caused by some unknown geo-fencing or anti-drone technology that might now be in place there. Frankly, that sounds less like a knowledgeable assessment of the log data and more like grasping at straws, so hopefully somebody can come up with something less speculative and more substantive to help the OP.

P.S. Regarding the general tone of MavicPilots, I came across a recent thread where you were the one who convinced them to put down the pitchforks. Nice work and I agree with you: some of them need to "lighten up a little".

DroneFlying Posted at 2017-4-12 03:50
Thanks for posting that, Jason. I have to admit to being a little disappointed that it was posted in Mavic Pro Help, because that's sort of a "back street" on MavicPilots and might not get the same type and degree of scrutiny that most posts of its kind do there, but at least Mike and Robby have noticed it. I did see that you had also posted a link back to this thread (per Mike's request) but that post is now deleted.

So far, though, all we've gotten is guesswork about this being caused by some unknown geo-fencing or anti-drone technology that might now be in place there. Frankly, that sounds less like a knowledgeable assessment of the log data and more like grasping at straws, so hopefully somebody can come up with something less speculative and more substantive to help the OP.

Yeah. I honestly wasn't expecting too much. Without the .dat file, there's only a limited amount of data to analyze.

Although I have to say I'm quite intrigued by the theories that have been presented on that thread.

fansecaeb8c2 Posted at 2017-4-11 06:45
worked it out
http://www.phantomhelp.com/LogViewer/Y22HVVA3TEW7TLUTFAJL/

40.71410141        -74.02853122        your last known coordinates .
At 2.11 you were flying in class B airspace
At 5.13 you went into Atti mode for 3 seconds until 5.16 seconds this would have caused some drifting but you were travelling fairly fast so might not have noticed.
At 7.03 you again went into Atti mode until 7.30 this is showing a fair bit of drift , you also got a abnormal compass warning at 7.22.
At 9.27 you lost gps at 9.28 nothing else in the log.

You screen would have shown Atti mode at 5.13 and 7.03 you should have had warnings flash across your screen, also at 7.22 you should have seen further warning for compass problem, you can check for these warnings in your app under warnings.
Why your AC didn't RTH , my guess is you lost gps and although droneflying thinks this might have returned quickly, at 7.03 you lost gps and were in Atti for almost 27seconds, so my thinking is your AC had none or little gps it now cannot return home because it doesn't know where it is, so will continue to drift until it crashes or runs out of battery.
Although your screen shows 19 satellites you signal shown in the scaling bars shows almost nil, those bars represent the gps signal you are receiving.

Even if you had regained radio signal , I think your AC may have decided because of distance and winds that it would not have enough battery to get back home, my thinking on this is that it may only use calculations up to critical battery and measure time and distance from that, if this was the case your aircraft would just land.

I don't know if the fact that you were in class B airspace had any effect .

hallmark007 Posted at 2017-4-12 07:38
40.71410141        -74.02853122        your last known coordinates .
At 2.11 you were flying in class B airspace
At 5.13 you went into Atti mode for 3 seconds until 5.16 seconds this would have caused some drifting but you were travelling fairly fast so might not have noticed.

thanks for this. I guess what im trying to understand is in your opinion was i at fault or was the mavic at fault. sure ive had gps losses before while flying but never a gps loss followed immediately by a RC disconnection and then no RTH. based on this my belief is that something went wrong with the mavic rather than my flying error...

fansecaeb8c2 Posted at 2017-4-12 10:20
thanks for this. I guess what im trying to understand is in your opinion was i at fault or was the mavic at fault. sure ive had gps losses before while flying but never a gps loss followed immediately by a RC disconnection and then no RTH. based on this my belief is that something went wrong with the mavic rather than my flying error...

Look I have to say it does not look good, a lot of what happened looks like it was the area you were flying in, you also had several warnings and decided to carry on, they may see it like that, loss of signal or gps will not be covered unless you had faulty receivers, and because don't have your aircraft how can it be proved or disproved.
if it was me let them have a look maybe try to do some sort a deal if the outcome is bad.

DISCONNECTS, DISCONNECTS AMD MORE DISCONNECTS!
Two years with an Inspire, a couple Phantoms and a Mavic, and never so many disconnects as today's flights with new firmware and new GO. Tried iPad Mini, iPad Pro and iPhone 6+. Miserab;e spirits to find myself in an unreliable flying situation.