I recently flew a 20 minute mission and when I downloaded the flight .dat files from the Mavic Pro my first flight was split into two dat files.  From what I understand there is an upper limitation on the size of the dat file and it appears to be built into the firmware to split the dat file into two parts when it reaches a certain size.
This is a problem since I upload the dat files to Airdata UAV and instead of one flight I have two seperate flights now. This is important to me since it's not unusual to lose RC signal and lose telemetry information so having the .dat file from the Mavic to upload to Airdata provides an accurate full acount of the flight.
Can this please be fixed so the flyxxx.dat files are not split into two for a single flight???
I would really appreciate an answer to this.

Below is a snapshot of the files.  Fly001.dat and Fly002.dat are a single flight, yet the fw on the Mavic split them into two.

Correct me if I'm wrong but doesn't Airdata only accept .txt files (e.g. DJIFlightRecord_2016-08-01_[11-15-07].txt) ? I thought the .dat file was encrypted and only readable by official DJI Repair Centers.

Not any more !  and big
They have been beta testing .dat files for weeks now and so far I've sent up about 10 .dat files.
There has been a small group of us who posted a request (last year) asking if they would ever be able to accept a flight dat file.  They kept saying they were working on it.
About 3 weeks ago I received an email stating they now accept them as an upload but the results are considered beta.
The results of the first few flight files I sent up had some minor tweaks they needed to do but so far they have been responsive in doing so.
It's made a huge difference for me since a lot of my flights went out of RC range thus the actual flight telemetry was missing.
Now, it's very accurate!
So, yes, they are taking the .dat files now; given that it's considered in beta testing, any flaws are being worked out when you report to them but I don't think they publicly announced it yet.

marklyn59 Posted at 2018-10-30 05:27
Not any more !  and big
They have been beta testing .dat files for weeks now and so far I've sent up about 10 .dat files.
There has been a small group of us who posted a request (last year) asking if they would ever be able to accept a flight dat file.  They kept saying they were working on it.

Ahah, I see! I really wasn't aware of that. Well yes it seems like DJI splits up the .dat files after a certain file size. Will check with my M2P once I have it available to see if it's the same there.

DJIJAKOB Posted at 2018-10-30 08:05
Ahah, I see! I really wasn't aware of that. Well yes it seems like DJI splits up the .dat files after a certain file size. Will check with my M2P once I have it available to see if it's the same there.

I'd appreciate knowing that.  I wonder what the size threshold is when it splits.