Short:
If possible could the stopGPSLogger() function not be called till the drone has landed in a future version? This is likely more complex than simply not calling the function till the drone is landed but the goal is to provide GPS data in the logs while the drone is returning home via the GO_HOME command and while landing.
Details:
(I have looked over the 7 logs and here is what I found)
The mission completed and the GO_HOME command was sent to the drone. At this time the drone was 375m from the last image location to the homepoint and the homepoint was accurately set according to the logs.
Given the Phantom 4 pro will go about 8m/s and the drone took ~40 seconds from TAKING_OFF > GOING_TO_MISSION I can assume it traveled the distance to the landing area. (it technically should have taken 6 more seconds but that doesn’t account for guide winds pushing it along )
From GOING_TO_LAND → LANDING to LANDING → LANDED took 35 seconds. From LANDED I went to a state of UNKNOWN (I suspect this is "normal’) about a minute later.
What I have tried to find the drone
I mapped all the GPS data of interest in my QGIS stack for the property to take accurate measurements and gauge where things might have gone wrong.
I walked from the last known point on the GPS, as indicated by the last image captured in the log, in a relatively straight line to the homepoint about 5 times. Its an open area without trees but I didn’t find the drone.
I walked around the landing point, which is clear for at least 50ft, and didn’t find the drone.
Current thoughts
Somehow in an open field the drone lost its 14 GPS satellites and it landed who knows where.
In the same vane the GPS was “off” and it landed who knows where.
The drone is still “near” the homepoint but something is obscuring it. (I did have trucks delivering fill that day 70ft away … fill I eventually have to move and it might be, sadly, under there)
I realize I should have been at the controls when the drone was coming home, it has flown this mission several times before without issues so I let it do its thing when coming back.