.DAT available

[BudWalker]

The .DAT that can be retrieved from the goggles using the Fly App is not encrypted; i.e it can be converted and analyzed. This is unexpected since the trend with DJI platforms has been to encrypt the .DATs. In addition, the .txt log files can also be retrieved using the method described below.

Note: Using DJI Assistant 2 to retrieve the log files from the goggles will yield log files that are encrypted. To get log files that are not encrypted the method described below must be used.

To retrieve a .DAT connect the goggles to a mobile device running the Fly App. The log file transfer will start after the Fly App indicates the goggles are connected. There doesn't seem to be a simple way to determine when the transfer is complete. I usually wait for 5 minutes.

Here is a YouTube that shows this process

Next transfer the FlightRecords directory from the Fly App to a PC (or, I suppose, a Mac or Linux) machine. The .txt log files appear in the FlightRecords directory and the .DATs appear in the FlightRecords/MCDatFlightRecords directory.

There are a couple of really good explanations about retrieving log files from the Fly App

1) The Locating Your Flight Logs section on this site
DJI Flight Log Viewer | Phantom Help

2) Section 3. LOG FILE RETRIEVAL in this post
Mavic Flight Log Retrieval and Analysis Guide

These .DATs can be processed by either DatCon or CsvView
CsvView Downloads
DatCon Downloads

 

[anethema]

On iOS I'm not clear how to get the file. I shut off syncing with the server, plug in...then what? You say they should 'appear' and be viewable in the flight app but I'm not clear what that means.

I found aircraft logs, they are 300+mb on the goggles. I tap the 'send' button but I'm not sure where they go from there. How do I actually get the logs into my computer? Thanks!

 

[Kilrah]

You need to use iTunes to access the "app file sharing" of DJI Fly.

DJI FPV Crash and Airdata HD Flight Player Data

I'm posting this in case it has happened to others, with a little advice for finding my drone. My DJI FPV drone crashed the first time in April while flying in the Californias desert. I was cruising and videoing in 4K in Sport Mode at 50 mph at full throttle and around 90 degrees outside...

fpvdronepilots.com

 

[anethema]

Thanks for the reply! I must be misunderstanding something. So I go into the flight data, then click history once I'm connected to the goggles right to see the flights on the goggles?

Like this(its a video if you click it):

https://imgur.com/IbapLr8

I don't see any DAT files in the folder though. Just a lot of text files: DJIFlightRecord-2021-06-05-[05-02-48].txt (That work in Airview but I'm looking for the more detailed DAT).

So that is looking in the FlightRecords folder, but I don't see any MCDatFlightRecords folder. Also that is looking on the files app. On iTunes in the "File sharing" section I dont even seem to be able to get into folders or copy them just individual files, but everything I'm seeing looks identical to what it looks like in the files app in the DJI fly folder.

Where am I going wrong ?

 

[anethema]

@Kilrah also here is a video of me trying to copy folders etc using iTunes:

ShareX GIF | Gfycat

Watch and share ShareX GIFs on Gfycat

gfycat.com

Just cant double click to get in the folder, or copy a folder, only files. Weird. But I don't think there is a DAT in there anyways since those folders are just whats in the Files app, and it doesn't contain a DAT even after I click that button in the 'history' thing.

 

[Kilrah]

Double-clicking the folder won't open it but normally you can save it entirely with the Save button at the bottom (you need to scroll down to see it, terrible iTunes UI)

 

[anethema]

Double-clicking the folder won't open it but normally you can save it entirely with the Save button at the bottom (you need to scroll down to see it, terrible iTunes UI)

Ya as I thought all that is in there is a list.json. Not DAT files. How do I get the DAT file to appear in that folder?

EDIT: Also it was that save button I feel stupid haha. Still no DAT tho

 

[anethema]

OK, for any dummies like me I figured it out. Other than my previous problem...

So, the issue I was having was having cleared my flight records then I kept going into the history and hitting download on stuff. I now have no clue what that does.

To make the files appear, I had to force kill the Fly app, then open it again, plug it into the goggles, then just let it start to sync (having disabled DJI sync before of course). Then the DAT files are in the MCDatFlightRecords folder.

Also FYI the files are the same ones as in the Files view, so you don't actually need iTunes. You can just select the files you want in there and copy them to a network share, or email them to yourself, whatever.

Thanks a bunch @Kilrah

Very cool seeing all this data.

 

[thetechnobear]

Also FYI the files are the same ones as in the Files view, so you don't actually need iTunes. You can just select the files you want in there and copy them to a network share, or email them to yourself, whatever.

yeah, the "Files" app is the way I transfer stuff these days ... esp. if you are using a mac, since you can simply use AirDrop to quickly transfer the files.
I guess, with windows, you'd just resort to using email...

also, if you have the camera connection kit (cck) , you can use Files to copy the file to a usb stick/usb drive.

 

[Kilrah]

No, never tried not to power the aircraft so far, could try at some point but given the app doesn't give any sign of "seeing" the goggles without the aircraft powered it didn't seem like it would, but maybe it does and does the sync i the background...

 

[anethema]

Actually I did all my syncing with just the goggles powered up. The little connection icon on the main page showed just goggles instead of goggles and aircraft and the “history” button in the flight logs just showed goggle files instead of goggle and aircraft files.
When I deleted all my flight logs and plugged into the goggles though the list repopulated without the aircraft powered on.

 

[JoeFPV]

Hey @BudWalker kind of late to this particular party. I was able to get a flight log dat file off the drone directly using DA(FPV specific version). I can extract it using your tool, however DatCon freaks out over it. Something about an invalid header and it assumes the clock speed and battery cell count. Resulting CSV has one line in it with 3 columns. Did DJI encrypt this file in the latest 1.02* firmware? I'm trying to get ahold of the gyro data to use for video stabilization. Murdering my brain digging into this. (FYI, I'm also a dev and do a lot of RE work so these processes aren't entirely new to me.)

Thanks for any help you can provide!

 

[BudWalker]

Hey @BudWalker kind of late to this particular party. I was able to get a flight log dat file off the drone directly using DA(FPV specific version). I can extract it using your tool, however DatCon freaks out over it. Something about an invalid header and it assumes the clock speed and battery cell count. Resulting CSV has one line in it with 3 columns. Did DJI encrypt this file in the latest 1.02* firmware? I'm trying to get ahold of the gyro data to use for video stabilization. Murdering my brain digging into this. (FYI, I'm also a dev and do a lot of RE work so these processes aren't entirely new to me.)

Thanks for any help you can provide!

The .DAT on the FPV itself is encrypted and can not be processed by DatCon. Follow the instructions in post #1 to retrieve the .DAT from the goggles which is not encrypted. DatCon and CsvView will be able to process this .DAT

 

[JoeFPV]

The .DAT on the FPV itself is encrypted and can not be processed by DatCon. Follow the instructions in post #1 to retrieve the .DAT from the goggles which is not encrypted. DatCon and CsvView will be able to process this .DAT

Ah, well that explains that then. I might have to root one of my android devices to get access to the DJI Fly apps data folder it seems. Your instructions appear only for iOS and I can't find any of the flight logs on my android device after grabbing the logs from the drone but not cloud syncing them. Thanks so much for pointing me in the right direction and the very rapid reply! Cheers!

 

[JoeFPV]

The dat files contained in the app directory on Android are encrypted. Looks like I'm out of luck in that regard.

 

[BudWalker]

The dat files contained in the app directory on Android are encrypted. Looks like I'm out of luck in that regard.

There are more than one folders that contain .DAT files. The folder you want is FlightRecords/MCDatFlightRecords. I would be very surprised if the .DATs are encrypted on Android but not on iOS.

I couldn’t quite tell from your description. Just to be clear, the .DATs are transferred from the goggles, not from the drone.

 

[JoeFPV]

There are more than one folders that contain .DAT files. The folder you want is FlightRecords/MCDatFlightRecords. I would be very surprised if the .DATs are encrypted on Android but not on iOS.

I couldn’t quite tell from your description. Just to be clear, the .DATs are transferred from the goggles, not from the drone.

Yes, I disabled cloud sync in DJI Fly, cleared the apps cache, connected goggles to the phone, powered up all devices and waited for them all to connect. Went into the flight log, went into the aircraft logs and chose the log that matched the date and time of an actual flight and copied it to my phone using the app. Then, because you can only access the user data file structure in a privileged shell, I navigated into DJI Fly's user data directory (/sdcard/Android/data/dji.go.v5/files/FlightRecord/MCDatFlightRecords). This directory was empty, but in a sibling directory HmsRecord, there are logs and dats for every system and device. The files all have .DAT.enc extensions. All of the log files are encrypted, most of the JSON files are encrypted. There is also a zip file containing all of the logs for all devices and services, the zip isn't encrypted, but the files within, to include the flight log are also encrypted. About 2GB worth of data. There are no other FLY*.DAT|dat files on the device. The data in the HmsRecord directory wasn't there prior to copying the flight log from the goggles onto the phone.

 

[Kilrah]

I would be very surprised if the .DATs are encrypted on Android but not on iOS.

DJI have changed where they stored the flight records and other data in a DJI FLY update a couple of weeks ago, didn't check it but I wouldn't be surprised if they "fixed" the lack of encryption at the same time...

If that is the case you'd be SOL for those particular logs but might be a good idea to downgrade the app to a version before that for future use.

 

[BudWalker]

Yes, I disabled cloud sync in DJI Fly, cleared the apps cache, connected goggles to the phone, powered up all devices and waited for them all to connect. Went into the flight log, went into the aircraft logs and chose the log that matched the date and time of an actual flight and copied it to my phone using the app. Then, because you can only access the user data file structure in a privileged shell, I navigated into DJI Fly's user data directory (/sdcard/Android/data/dji.go.v5/files/FlightRecord/MCDatFlightRecords). This directory was empty, but in a sibling directory HmsRecord, there are logs and dats for every system and device. The files all have .DAT.enc extensions. All of the log files are encrypted, most of the JSON files are encrypted. There is also a zip file containing all of the logs for all devices and services, the zip isn't encrypted, but the files within, to include the flight log are also encrypted. About 2GB worth of data. There are no other FLY*.DAT|dat files on the device. The data in the HmsRecord directory wasn't there prior to copying the flight log from the goggles onto the phone.
View attachment 5570

Now that you have disabled sync try to create a new .DAT. The only .DATs that will work are in the MCDatFlightRecords directory.

 

[Michael610]

Probably showing my "newbie-ness" but...I never had any luck with the DJI Fly app. But when I installed DJI Assistant on the computer and connected the goggles to it (something DJI Support never suggested I do, which seems odd...) boom! I could sync it, and I was able to export the DAT file.
Note that the FLY app wasn't installed onto the phone until AFTER the incident...but if DJI Assistant was able to access the goggle data, DJI Fly on the phone should have had just as easy a time as Assistant did...
I think I will call them to see what if they can do any analysis on this DAT...