Lost Mavic Pro after GO app crash

[pongmaster21]

Hi all,
My Mavic Pro, I think, had a bad crash few days ago. Hopefully not that bad. Thankfully no damage to people, animals or property of others.
While returning to the home point I noticed on the GO 4 app that the battery status went from 20% to N/A. It was a new battery too, only 7 flights recorded on it. About 5 seconds later the GO 4 app crashed. I restarted the app but I was not able to re-connect to the drone. On the RC it indicated the battery dropped to 16%. About another 10 seconds later "LANDING" appeared on the RC. I searched at the coordinates that "find my drone" recorded but I was not able to find my Mavic Pro. I have returned to site a few times and looked in other areas close to the coordinates but unfortunately still no drone.
At the end of the flight log the mavic stopped and pivoted. The distance and height did not change. That is where it landed was not recorded because the GO 4 app crashed. So I really need some help discovering where this puppy might have landed.
So all I have the information on the RC called the "BlackBox". But the files are encrypted I can't read them. So question is: I've managed to download all the BlackBox files from the RC using DJI Assitant 2.
But how can I view and analyze that data from RC? The following link contains the files Mavic_RC.zip and Mavic_FL.zip. The RC file contains the BlackBox information and FL contains all the flight logs I was able to grab from the DJI folder on my phone. Please help. I know it's out there and some place close to last known GPS coordinates.

Mavic - Google Drive

 

[janko216]

And what do you have in folder "Flightrecords"?

 

[Kilrah]

And what do you have in folder "Flightrecords"?

That's in what he provided... and won't contain what happened after the app crashed.

RC logs don't contain position information.

When the app crashes it doesn't prevent you from flying, so... best would have been to just fly home. The RC screen has all the info you need for that.

 

[pongmaster21]

The flight was on 10-24 at about 17:30. I have gathered all the flight logs from that date. You can find them here.

Going back today to conduct another search.

Mavic - Google Drive

 

[DanMan32]

That's in what he provided... and won't contain what happened after the app crashed.

RC logs don't contain position information.

When the app crashes it doesn't prevent you from flying, so... best would have been to just fly home. The RC screen has all the info you need for that.

Except for the heading. I suppose you could use delta in distance to figure it out if you can't see it.

 

[pongmaster21]

Yes. I was hoping the RC might contain the real distance from the home point and the height. The flight log ended when the AC was at 158 feet up. I've been looking up in the trees my neck is stiff.

 

[Meta4]

The flight was on 10-24 at about 17:30. I have gathered all the flight logs from that date. You can find them here.
Going back today to conduct another search.

Here's your flight data:
DJI Flight Log Viewer - PhantomHelp.com
You were flying back but at 2:57.8 and 158 feet up, you took your hands off the sticks and the drone slowed to a stop a few seconds later.
At 3:00.0 you had a loss of downlink (video signal) for 4.3 seconds but would have still had control signal and been able to continue flying.
The flight record continues until 3:15.3 but you didn't touch the sticks to do any flying.
The data ends with the Mavic hovering at 42.79285995 -70.95591373 and 158 feet up with the battery running low (16%).
That point is 780 ft from home.

Unless you changed the default Loss of Signal Action (almost no-one ever changes it), the mavic should have attempted to RTH on loss of signal.
Your launch point was 50-60 feet higher than the terrain at the drone's last recorded location and there are no obstacles that could have blocked the RTH path.
It looks like the wind conditions wouldn't have prevented RTH.

This shows where the last recorded location was.
The drone should be somewhere between there and home.

 

[pongmaster21]

Thank you for this valuable information. I do appreciate it.

Right around the last known location a message appeared on the screen it said, "Landing".

Is there information in the logs that support that?

I have searched this area 5 times now. I can't seem to locate it. I keep looking up to the tree tops hoping I might see it hanging. I believe I'm conducting a very thorough search.

 

[Meta4]

Right around the last known location a message appeared on the screen it said, "Landing".
Is there information in the logs that support that?

The flight data shows no message indicating that the drone was landing and the altitude had not changed for a long time.
Do you see that message if you play back the flight record in the app?

 

[pongmaster21]

I did not see that message in the flight record and I did not think I would see it since the app crashed before this happened. Once the app crashes it was my understanding it would not write any more data to the flight log. Is that correct?

It may have done a RTH. I had left that location once I noticed the message "Landing" appear. I did check the RTH area once I returned but was not able to locate it.

Thanks for your assistance thus far. You knowledge and understanding is commendable.

 

[Meta4]

I did not see that message in the flight record and I did not think I would see it since the app crashed before this happened. Once the app crashes it was my understanding it would not write any more data to the flight log. Is that correct?

If the app is not running, it can't record anything.
But as long as you have signal, you can still control the drone even if the app crashes.
If you saw a Landing message on the controller screen, that suggests that you still had signal.
RTH would not have initiated if you still had signal (if you'd switched off the controller it would have initiated RTH).
That suggests that it stayed hovering waiting for your control input.
Since it was at 16% battery, it would have reached critical low voltage after a short time and autolanded.
So the area around the last recorded location is the most likely place to search.

 

[Meta4]

I have searched this area 5 times now. I can't seem to locate it. I keep looking up to the tree tops hoping I might see it hanging.

The last recorded location appears to be within that 100 ft x 60 ft rectangular patch of vegetation that sticks out from the eastern boundary of the cleared area.
There's one big tree visible in Google Earth that might be a drone collector?
Here's a link to see it on Google Earth for yourself:
https://www.phantomhelp.com/LogView...B/DJIFlightRecord_2018-10-24_[17-03-37] 1.kmz

 

[Kilrah]

I suppose you could use delta in distance to figure it out if you can't see it.

Yep, works perfect.

 

[lertsek]

Great job Meta4! I just learned how to view the flight records, but haven't messed with the logs yet.
Wish you the best pongmaster.

 

[DanMan32]

P3 was prone to losing all downlink but still have uplink.
M2 seems to take that into account and prompt you if you want to RTH.

 

[Yooper2nc]

I am a new owner of a Mavic and seeing these posts of lost connection really makes me nervous to fly. Is there a prevention or a SOP of what to do in case of signal or app failure? I am one who panics if I don’t have visual on the drone. Had a nice phantom 3 which my brother crashed so I replaced with the Mavic which is much harder to see.

 

[sar104]

I am a new owner of a Mavic and seeing these posts of lost connection really makes me nervous to fly. Is there a prevention or a SOP of what to do in case of signal or app failure? I am one who panics if I don’t have visual on the drone. Had a nice phantom 3 which my brother crashed so I replaced with the Mavic which is much harder to see.

You might consider adding a high-intensity strobe, such as these:

STROBON Cree LED Strobe Light - Phantom Help

 

[Oto]

@pongmaster21 did you recover your drone?

 

[DanMan32]

Mavic will by default return home on RC-AC signal loss.
Later models will retrace their steps back 60 seconds, then if no signal or you don't respond when signal returns, it heads home.

 

[Oto]

Mavic will by default return home on RC-AC signal loss.

Except it also loses GPS or has other error then it will force land.