I lost my Mavic earlier. I was flying it and I lost contact as it started to go behind a hill. I moved to get into a better spot since I had flown there coulntless times, but I could not make contact again. I was in Sports mode, so maybe it continued i's path for too long and fast before and after the signal was lost.

I drove to the area where I last observed on the video. I made contact with it. It looked like it was under a tree, and the message on the screen was that it could not lift-off because it was not level. It was getting dark, so I turned on the location flash and sounds. I did not hear anything or see anything. I tried to locate it on the map, but it didn't seem to know where it was. The remote said that it had GPS, and I had good signal.

I moved around to see if my signal level would increase or decrease, but I got inconsistent results. Sometimes walking in a direction would make the signal level rise, other times, the same spot would have differnt results. I tried staying in one spot, rotating to see if the antenna position could help me out. No luck.

My last attempt was to download the last video so that I could see where it was before it ended up under the tree. The flight video on my phone stops when the signal stopped. The video file must be husge. I started downloading it and even though I still had about 20% charge on the drone when I started, it did not complete before the drone ran out of juice. By then it was dark too, so I would have seen the flashes if the Mavic was close by.

I am now trying to get the logs and any partial video files off the phone, although the one that was being downloaded from the drone while the battery ran out, is probably in a /tmp directory and is unavailable to me.

Not sure what I can do.

Oh, I also checked the Find My Drone area of the app. It shows the drone in the same spot that I lost signal. I was walking around that spot, or very close, but did not see nor hear it. That area is very hilly and there's lots of poison oak, so I couldn't stay out there and keep walking around in the dark. I am hoping I can get some better ideas of where to look before I go back tomorrow.

Can anyone tell me where I can find the tools to read the log files? I am hoping that while I was connected to the Drone before the power went out, and it was still downloading the video, that it might have sent some information, like the GPS location before it went under the tree, or how far it tried to go to RTH or not, after the signal was lost.

I am very surprised that RTH did not bring it back to me. But I have had it behave oddly when in sports mode when signal goes out and comes back and it seems to not know whether to continue RTH or Sports mode.

RTH with Sports mode might be problematic too since the obstacle detection doesn't work or work as well in Sports mode?

I am enclosing the screenshot of the Find My Drone screen. Is that location supposed to be where the drone was last reporting after the disappearance, or merely where my phone last had contact in-flight? Because that is where I was and could not see or hear it. I was assuming that maybe that was just where it last communicated before going down. Why it wouldn't update after when I had video signal, is beyond me.

Thank you!


-mz

Can anyone tell me where I can find the tools to read the log files?

DJI Flight Log Viewer

The link has instructions for its use.
If you want help from members here, post the Link the Viewer outputs.

Hello and good day mz. I'm really sorry to know what happened to your previous flight with your DJI Mavic 2 Pro. I would recommend you to contact our support team to start up a ticket: https://www.dji.com/support?site=brandsite&from=nav . We have the professional team who would do their best to find out the reason of the incident and then the corresponding resolution would be provided. Please note that DJI will not perform data analysis for cases occurring after the expiry of the warranty period; otherwise, valid charges will apply. Thank for your support.

Hello!! I found my drone. Wasn't easy. It was under a bunch of oaks and bay trees, on the ground. It was a miracle it made it through the canopy. To find it, I watched the video cache from the DJI Go4 app, and extrapolated the last little hook to the right, and searched there instead of where the "Find My Drone" told me to look. It was a good 200 yards away, and 50 ft or so uphill. I actually looked until it was dark and then used a flashlight hoping to get a glint of something different than organics (It was a bit Blair Witchy out there, with no people nearby, and much rustling in the bushes).

I’m surprised that the Find My Drone screen didn't update its location once I was nearby the night before, before the battery ran out.

I'm sure you are dying to know: nothing was broken but 3 props that were dinged and one that was completely missing. Lucky that I found it and lucky that everything is functional and unscathed. My DJI Care would have been useless without a drone, and now I don't even need to send anything in.

Now to figure out why this happened. I had been going towards the reservoir, but intended to stay on one side of the road, and was going to curve around with the road. When the signal went out, it seems like the drone was just starting a slight turn to the right.

Here is the cache video file from the remote leading up to the crash:  (I have the video from the drone now and that is at the end)

https://www.dropbox.com/s/c1ce0t ... ectionloss.mov?dl=0

Here is my flight record file leading up to the crash. The data seems to stop right where the Remote video cache ends.
Screenshot of that:
Flightrecords:
https://www.dropbox.com/s/tnks3f ... 9-35-29%5D.txt?dl=0

I don't know if these can help, but they are the DJILogxxxx.log files. The last two from before the crash.

https://www.dropbox.com/s/o5vl6f ... D%28987%29.log?dl=0

https://www.dropbox.com/s/2znjl1 ... D%28880%29.log?dl=0

Finally the crash video from the drone:

https://www.dropbox.com/s/n72z2l ... omthedrone.mp4?dl=0

There’s a lot going on there. Looks like I started to go around the hill and lost at least video signal, so I turned away from the hill. Did I end up doing about a 300 degree turn and face the hill? And then go straight into the hill? My recollection was that I tried to turn away slightly and to climb, but then I let the controls go to allow the signal loss RTH to do its thing. However, it looks like RTH might have tried to descend to RTH altitude? Does it to do that or if RTH altitude is less than current altitude does it stay at that altitude?

Then there’s the spectacular high speed crash, and then the ground. Now, why the heck are the motors still running on the ground?

Now how do I get the flight log from the drone, since the one on the phone ends prematurely? I don’t have a USB-C cable handy right now.

-mz

mz-in-norcal Posted at 4-23 06:56
Hello!! I found my drone. Wasn't easy. It was under a bunch of oaks and bay trees, on the ground. It was a miracle it made it through the canopy. To find it, I watched the video cache from the DJI Go4 app, and extrapolated the last little hook to the right, and searched there instead of where the "Find My Drone" told me to look. It was a good 200 yards away, and 50 ft or so uphill. I actually looked until it was dark and then used a flashlight hoping to get a glint of something different than organics (It was a bit Blair Witchy out there, with no people nearby, and much rustling in the bushes).

I’m surprised that the Find My Drone screen didn't update its location once I was nearby the night before, before the battery ran out.

https://www.phantomhelp.com/LogViewer/7PZF4I7020S437RROXGJ/

This is how it looks in logviewer.

Yes but that’s still missing the drone’s point of view. I want to know what made it turn and head into the trees since that was after signal loss. My recollection was that after signal loss I waited for RTH but the video here shows an immediate change in course leading to a quick crash. Not enough time for RTH to kick in.

Always setup your RTH to be much higher than the closest tallest object within the radius of you and the drone.

RTH was never activated .  The drone at the end of the flight looks as though it was fully respondent to pilots inputs.

At all time the right stick appears to be fully pressed forwards giving you maximum forward speed in sports mode.

At 10m 11.2  at an IMU altitude of 492.5ft  you started the drones decent. With right stick fully forward.

At 10m 46.8  you cancelled your decent at a IMU height of 154.9ft still with right stick fully forward the whole time.

Although you released the decent stick at  10m 46.8 the at 154 ft the drone continued to descend as you were in sport mode the final drones altitude of the IMU was around at 137-138 ft it was this altitude when it finally hit the trees.  Flying forward at full speed as per your input to the controller.

Flying to low, out of LOS in sport mode..... always gunna end bad ...

It should be easy enough to find it looks like it finally come to rest on the grass at least and not up a tree.

Use google maps, the last knows gps data and video to locate its down position...

mz-in-norcal Posted at 4-23 16:43
Yes but that’s still missing the drone’s point of view. I want to know what made it turn and head into the trees since that was after signal loss. My recollection was that after signal loss I waited for RTH but the video here shows an immediate change in course leading to a quick crash. Not enough time for RTH to kick in.

The .DAT file in Mavic log will tell you what happened after you lost connection.

G_Sig Posted at 4-24 06:27
The .DAT file in Mavic log will tell you what happened after you lost connection.

I hooked up the Mavic 2 to my computer using a USSB-C cable. Two volumes mounted. One was the SD card and the other the internal memory. Neither of them had any .DAT files. Is there another place to look?

Thank you all for your help!

Sky Donkey Posted at 4-24 05:35
RTH was never activated .  The drone at the end of the flight looks as though it was fully respondent to pilots inputs.

At all time the right stick appears to be fully pressed forwards giving you maximum forward speed in sports mode.

How quickly after signal loss does the drone:
- stop previous control commands and just hover?
- switch modes?
- start RTH?

I'm gathering from these responses that the first two and possibly three, never occurred.

mz-in-norcal Posted at 4-24 22:37
I hooked up the Mavic 2 to my computer using a USSB-C cable. Two volumes mounted. One was the SD card and the other the internal memory. Neither of them had any .DAT files. Is there another place to look?

Thank you all for your help!

This will help you to get the files.
datfile / retrieve V3 Dat.

G_Sig Posted at 4-24 23:32
This will help you to get the files.
datfile / retrieve V3 Dat.

Does this tool work with the files that get uploaded to the DJI cloud as part of your flight history.

DAFlys Posted at 9-26 01:51
Does this tool work with the files that get uploaded to the DJI cloud as part of your flight history.

It doesn't. This tool is for viewing the .dat files on the internal/non-removable micro sd card inside the drone.
The .dat files are hard to understand for non-professionals.

If you want to review your flight records which you can sync with the DJI cloud (those are .txt files) there is a great tool for it online:
https://www.phantomhelp.com/LogViewer/Upload/

You can also upload your flight records here and review lots of information that is included in your log:
https://app.airdata.com

Eric13 Posted at 9-29 08:59
It doesn't. This tool is for viewing the .dat files on the internal/non-removable micro sd card inside the drone.
The .dat files are hard to understand for non-professionals.

CsvView does work with TXT files in addition to DAT files. Also, the onboard DAT files on more recent (Mavic 2) models are encrypted and unreadable by CsvView, but the tablet DAT files are still readable.

Thanks for sharing

Eric13 Posted at 9-29 08:59
It doesn't. This tool is for viewing the .dat files on the internal/non-removable micro sd card inside the drone.
The .dat files are hard to understand for non-professionals.

The files the app syncs are zip file but they cannot be opened, Although AirData have managed it.