P4P lost all satellites during flight

Greetings all, new here!

I’m still pretty new to flying (2 hours total flight time). Yesterday I had a little bit of a scary flight. I had 16 satellites when taking off and mid flight I lost all of them. The drone switched to ATTI mode and I felt like i lost control because I have not practiced flying in the mode (my bad!). I assume that it seemed like it was moving without command because ATTI does not air brake when off the controls and the drone was still moving in the direction of last input (before I lost gps). Do you think that is correct?

After uploading my flight log It appears I was having GPS issues immediately after takeoff, but did not lose satellites. Around 5m 9s is when things start to go haywire. Can anyone more skilled than myself make some more sense of what happened? Should I be worried about a faulty GPS module since I lost GPS or do you think there was some sort of interference?

Here is the log: https://www.phantomhelp.com/logviewer/TDFKQ6N5OP99PW7WALWO/#

Thanks in advance for the help.

This seems to be a problem with the GPS module itself. Several times during the flight it switched from 16 sats to 0 sats and then back to 16. I can’t think of any reason to suspect a compass issue.


My advice? It’s gotta go back to DJI for repair.

If you want to know more about the GPS failure you’ll need to provide the .DAT log from the P4P. Look here to see how to do that.It’ll be large so you’ll need to Dropbox it (or similar).

Thanks for the input! I corrected my original post to say GPS module. Those drop cycles certainly don’t look normal!

Here is the .DAT file Dropbox - DJI_ASSISTANT_EXPORT_FILE_2019-01-28_20-31-02.DAT - Simplify your life

I looked at the .DAT and didn’t learn much more than we already know. The eventLog stream has several entries related to problems with the GPS. I’ve attached it if you want to take a look.

If you want to avoid a trip to DJI repair you could disassemble your P4P and check the connections to the GPS module and the antenna connection.

FLY059.log.txt (10.2 KB)

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Thanks for the help! I was able to accurately explain to DJI what the issue was which I think expedited the process.

The analysis they provided said: “Before t = 2:00, there are two times that the GPS signal occured jitter at the height is around 5.6m and 23.2m respectively and from t = 5:08 to the end, the GPS signal absolutely lost when the AC was in high air and the AC entered ATTI mode. The AC is in warranty period, please send back for free repair.”

DJI is currently repairing it under warranty.

Thanks again!

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