Mavic lost in sea

[demme]

Hi, my mavic got an error 100m out over the sea,I lost all controll, RTH did not work. It just lost altitude and then it was 0.1 and then all signals lost.


I wonder, is there anyway to find out it last know. coordinates b4 Iost control. I know most data are stored in the mavic but how about the RC?

 

[sar104]

DJI Flight Log Viewer

 

[msinger]

If you were using DJI GO or Litchi, you can upload the flight log at the link above. You'll find instructions for locating the flight log there. After uploading your log, download the linked CSV file to find the coordinates.

 

[demme]

If you were using DJI GO or Litchi, you can upload the flight log at the link above. You'll find instructions for locating the flight log there. After uploading your log, download the linked CSV file to find the coordinates.

Oh, rly? Are there really last known GPS in a flight data file on the RC that will show where the mavic went down or at least show a position near that? Sounds very good if that's true. I was only aware of flight data being retrieved from the mavic itself, but that makes it hard with only a RC available...

Either hire a diver at known position, or buy a new mavic(,need a drone for real estate in 9days) !!

 

[msinger]

Are there really last known GPS in a flight data file on the RC that will show where the mavic went down or at least show a position near that?

You'll only be able to find the last coordinates recorded by DJI GO. Whether or not that's the exact location depends on what happened after the downlink disconnected. Data is only recorded in the TXT flight log while the downlink is connected.

 

[sar104]

Oh, rly? Are there really last known GPS in a flight data file on the RC that will show where the mavic went down or at least show a position near that? Sounds very good if that's true. I was only aware of flight data being retrieved from the mavic itself, but that makes it hard with only a RC available...

Either hire a diver at known position, or buy a new mavic(,need a drone for real estate in 9days) !!

The mobile device log is not as comprehensive as the onboard DAT file but it still contains a lot of data, including 10 Hz position data in lat/long. If you had line of sight to where it went down then the device log will have good coordinates. The bad news is that immersion in salt water causes extensive irreversible damage to the electronic components, so it's unlikely ever to fly again without a complete rebuild.

 

[demme]

The mobile device log is not as comprehensive as the onboard DAT file but it still contains a lot of data, including 10 Hz position data in lat/long. If you had line of sight to where it went down then the device log will have good coordinates. The bad news is that immersion in salt water causes extensive irreversible damage to the electronic components, so it's unlikely ever to fly again without a complete rebuild.

Thanks! I'm wondering if the file could contain information that show that it was a faulty machine and not my fault or something?

Well for now I'm really hoping for the text file having GPS that I can put into Google maps or something similar. About the rust, it's a small lake, no salt water thank God.

I've seen a bunch of mavics being found in deep water, dried for days and then working again.

 

[sar104]

Thanks! I'm wondering if the file could contain information that show that it was a faulty machine and not my fault or something?

Well for now I'm really hoping for the text file having GPS that I can put into Google maps or something similar. About the rust, it's a small lake, no salt water thank God.

I've seen a bunch of mavics being found in deep water, dried for days and then working again.

The file contains plenty of telemetry; it may or may not definitively indicate what caused the problem. If you post it we can take a look and tell you.

 

[demme]

Hey,

I'm running a PC, connected usb to side port on RC, turned it on and windows recognized a new device.

Getting logs from the Mavic RC is not this easy, after googling for many hours. First you need to find a file called "DjiDownloadTool_v1.5.exe", and then you extract files but non of these files are a .txt filed and all are invalid when I try to upload them.

These are the files pulled from DJI Download tool 1.5 (first picture) and last one the files pulled from Dji Assistant 2.

Anyone?

 

[msinger]

Getting logs from the Mavic RC is not this easy, after googling for many hours.

Skip the googling and follow the instructions here instead.

 

[demme]

Skip the googling and follow the instructions here instead.

That is exactly what I did, before googling.

Connecting my RC via the side usb port to my PC, a popup comes up, showing a new device has been installed.

Now, I'm have real trouble finding something called "DJI/dji.go.v4/FlightRecord", or similar. For starters, I dont even know where to look for them, since no new storage device, usb device is availale to explore?

What am I doing wrong? It's not like the instructions are advanced and I'm really not that stupid....

 

[sar104]

Hey,

I'm running a PC, connected usb to side port on RC, turned it on and windows recognized a new device.

Getting logs from the Mavic RC is not this easy, after googling for many hours. First you need to find a file called "DjiDownloadTool_v1.5.exe", and then you extract files but non of these files are a .txt filed and all are invalid when I try to upload them.

These are the files pulled from DJI Download tool 1.5 (first picture) and last one the files pulled from Dji Assistant 2.

Anyone?

The logs are not on the remote controller, they are on your mobile device.

 

[demme]

Okay...as I'm using DJI CrystalSky, it was a bit trickier. I had to mount a USB stick to the side of the crystal sky, when I did that, bot the usb stick +
the internal storage of CrystalSky was shown in windows explorer.

Nothing happened before when I hooked up the crystalsky to my PC, I can also not find any option to "turn on USB storage". But like I wrote, when I mounted a stick in the usb port, this automaticly came up:

 

[demme]

Okay...

Here are KML, CSV and flight logs on my google drive, I've put them in 1 different maps.

In the first map are files from when it first when crazy and I lost all control, in the second map are the files when I regained connected by walking towards where I thought the drone was.

DJI - Google Drive

In the first one, there a loooot of errors omg...

I've added flight log just from 3 days before, not a single error. It's in "Normal flight......."

How will this work on warranty? As I can't send in the drone to DJI or the retailer where I bought it...?

 

[sar104]

Okay...

Here are KML, CSV and flight logs on my google drive, I've put them in 1 different maps.

In the first map are files from when it first when crazy and I lost all control, in the second map are the files when I regained connected by walking towards where I thought the drone was.

DJI - Google Drive

In the first one, there a loooot of errors omg...

I've added flight log just from 3 days before, not a single error. It's in "Normal flight......."

How will this work on warranty? As I can't send in the drone to DJI or the retailer where I bought it...?

The files in flight 1 and flight 2 are identical - they are both DJIFlightRecord_2017-10-31__18-29-34. Did you intend to post DJIFlightRecord_2017-10-31__18-43-12 as the second flight?

 

[demme]

The files in flight 1 and flight 2 are identical - they are both DJIFlightRecord_2017-10-31__18-29-34. Did you intend to post DJIFlightRecord_2017-10-31__18-43-12 as the second flight?

Hi,

Yeah my bad, so many files that I mixed them up. Should be correct now.

Funny thing is that when I look at a flight log at some point, it shows a position way, way from here. The battery would not even last that far. But when I look at last known gps position at the last flight log, the route ends in the sea....

I've sent these logs to the store where I bought the mavic, maybe I should send them to DJI support as well?

 

[sar104]

Those two records are correct - a new one was started part way through the flight. There are multiple compass-related errors that are hard to diagnose, but resulted in the FC switching to ATTI mode. After that its behavior is a combination of eastward drift on the wind and somewhat random stick inputs on your part. It did not end up in the sea - it was last recorded heading NE at over 50 km/hr, at 59.74614994° N, 14.52274262° E, at an altitude of 115 m with 28% battery remaining when downlink was lost permanently.

However, if you look at the period from 910 - 980 seconds in the 2nd log, with no stick inputs it was drifting east at around 4 m/s. If it lost uplink at around the same time as downlink then it would have slowed and reverted to that course and speed. Extrapolating to 15% battery for auto land, that would allow it to move another 170 seconds or so, which would be around 650 - 700 m. That would put it around 59.746°N, 14.534°E, as shown on the map image below.

 

[demme]

Thanks!

I also found that weird ”final” route when looking into the flight log. But I don't know how it would have gotten that way, I did not command it like that after the first flight log/fail. Seems like you know your stuff anyway, I'm gonna walk around that area you pointed out today.

Anyway, like u said very weird readings and crazy stick inputs by me, I did not do that and I certainly didn't do the compass errors and the other stuff. It has worked flawless for a month until yesterday.

What do you think the drone store where I bought it about this? Let's say that I don't find the mavic, should the behaviour go on the warranty?

So many thoughts in my head now.. 6am here still haven't slept. :/

I still wonder how it manage to first lose control, land itself in the water...regaining control and then going the last part. I'm having a really hard time thinking that I did something to cause that.

 

[sar104]

Thanks!

I also found that weird ”final” route when looking into the flight log. But I don't know how it would have gotten that way, I did not command it like that after the first flight log/fail. Seems like you know your stuff anyway, I'm gonna walk around that area you pointed out today.

Anyway, like u said very weird readings and crazy stick inputs by me, I did not do that and I certainly didn't do the compass errors and the other stuff. It has worked flawless for a month until yesterday.

What do you think the drone store where I bought it about this? Let's say that I don't find the mavic, should the behaviour go on the warranty?

So many thoughts in my head now.. 6am here still haven't slept. :/

I still wonder how it manage to first lose control, land itself in the water...regaining control and then going the last part. I'm having a really hard time thinking that I did something to cause that.

The compass/yaw errors are equipment problems - nothing that you did. The stick inputs are real and the aircraft responded appropriately during both segments of the flight. It appears that it went into autoland after losing uplink in ATTI mode, which was why it descended to the water, but then uplink was restored at 903 s and a few seconds later at 912 s you gave it throttle input that caused it to ascend again. It also dropped back into ATTI mode and started drifting at that point. It's not clear if it ever touched down, but it was close.

 

[demme]

So I've just spend 5 hours walking around last known position and going east where the wind was blowing and making the mavic drift like u said, but I if you ever have walked in a swedish forest...there's not much hope. I found nothing.

I have opened a case with DJI anyway, gonna send them all my logs etc.