FlyApp 1.2.2 flight path incorrect

Skerrabrae · Jan 20, 2021

Some of the flights in the DJI Fly app 1.2.2 seem to have incomplete or incorrect data.

This seems to be particular to longer flights, over 1 km. As can be seen below, I am only 10 seconds into the flight yet it shows my distance as 418m. I've noted that at 0 seconds, the distance is 0m. Once I go to 01 second, it instantly jumps to 322m.

I always ensure I have a solid GPS lock before I take off from my home point. This same issue has occurred on multiple flights on different locations and different days. Has anyone else experienced this or know what the cause of this could be?

Skerrabrae · Jan 21, 2021

To dig deeper I loaded one of my flight logs. I noted that my flight logs don't even begin until 01m 25.4s after I took off. To reiterate, I did wait for GPS to lock in. I'm pretty sure I also waited for the home spot to be updated because I see the home spot marked on the Fly app screen above.

The flight log below shows the first entry at 01m 25.4s. It also shows an alert at that point that "Mode changed to P-GPS" Could this be the reason why I am missing the first minute of my flight logs? Incidentally, there are 2 more entries further down the log that also state "Mode changed to P-GPS".

Out of curiosity what does this mode change signify?

eaglesurfing · Jan 21, 2021

I would test this in another location to see if it matters.
If it does not then think about delete and reinstall firmware and app.
It is also possible that this has happen to someone else and they might have the fix.
Have you done a search on this forum for this problem yet?

vjpapa · Jan 21, 2021

Which controller are you using and how many satellites did you have? I have the smart controller and you must calibrate everything(controller, aircraft, joy sticks) - point antenna FLAT side at bird).

Skerrabrae · Jan 21, 2021

I am using a DJI Mini 2 with the standard controller it ships with. At the beginning of the flight I had 21 satellites.

I have experienced this same issue with missing the first minute of flight from at least 3 different locations.

Does not seem so far like anyone else has experienced this issue or not noticed it in their flight logs

vjpapa · Jan 21, 2021

Not sure about the firmware for the Mini but for the MA2 firmware update issues have created much frustration. There have been reports of updates removing features of previous updates, which is fine if they improve the feature but if the feature is totally removed then you don't have the control or safety features designed for the original aircraft.

So..... you could do a total reset of the controller and also dump the version of the aircraft firmware you presently have, then install an earlier version, fly and take notes. Then update the firmware to the latest version and compare, etc. but be careful, use an open field and keep the Mini in sight.

Skerrabrae · Jan 21, 2021

Checking the flight logs closer revealed that the "missing" section of my longer flights is not missing but was recorded in another flight.

So the first 1m 25.4s stopped recording as one flight and then immediately switched and started recording to another flight. Definitely not expected behavior but the data seems to all be there.

I'll just wait for the next DJI Fly update and firmware update and see if this persists.

DanMan32 · Jan 22, 2021

Did you have a connection loss between the RC and your phone, or did the app crash at all? Those two conditions can cause a flight to be split into separate logs.
I've seen that when the logs get split, one of them might not show up in the flight list. Can't recall if that observation was only in Go, Fly, or both.

Skerrabrae · Jan 22, 2021

DanMan32 said:
Did you have a connection loss between the RC and your phone, or did the app crash at all? Those two conditions can cause a flight to be split into separate logs.
I've seen that when the logs get split, one of them might not show up in the flight list. Can't recall if that observation was only in Go, Fly, or both.

Yes, in retrospect the DJI Fly app did crash on me in flight. That is the answer why my flight logs were split. My mystery is solved. Thanks for the insight!