Propeller/Motor Malfunction

[Sam_B]

I was flying my MM over a river, and looked down at the video, it suddenly flipped upside down (not my phone, just the drone)!
I heard the motors shut down, and it plummeted into the river at about 7m/s from about 25m high (according to the flight path/playback in the app).
I think what caused this is a single motor malfunction (one motor stopped spinning - causing it to flip over - causing all the other motors to stop spinning!
Anyone else had this problem!??

 

[eaglesurfing]

Welcome to the forum and someone will ask to see your files to help locate the problem.
Do a search on this forum to get that info.

 

[Deleted member 103366]

Tha attached shows the path or folder chain to flight logs using an android phone and a windows PC.
Iphone and windows needs itunes on the PC.
I think Iphone and MAcbook needs itunes on Macbook .

'Oddly'? Linux sees the logs on an iphone as easily as windows does

 

[Sam_B]

I have located the flight logs, and also a cached file (720p) of the crash:

 

[Sam_B]

Here's the video of it happening

 

[Deleted member 103366]

I think the DAT file is probably going to be of more use, it will have a name similar to
2021-02-06_`15-mm-ss_FLY058.DAT it should be in the MCDatFlightRecords folder..


No video

 

[Sam_B]

Ok, I'll have a look for the DAT file. Here's the cached video (don't know why it didn't send):

CRASH.mp4

MP4 File

1drv.ms

 

[Sam_B]

Apparently the MCDatFlightRecords folder is empty:

 

[Sam_B]

Are these useful??

 

[Meta4]

I was flying my MM over a river, and looked down at the video, it suddenly flipped upside down (not my phone, just the drone)!
I heard the motors shut down, and it plummeted into the river at about 7m/s from about 25m high (according to the flight path/playback in the app).

Here's what your flight data looks like:

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

It shows that there was a problem with either a front motor or a prop.
You were flying in Sport Mode 17 metres higher than the launch point and descending further.
At 15:33.3 something goes wrong and the Mavic starts to rotate anti-clockwise as it tips forward.
The drone is soon spinning and wobbling as it loses height.

The drone did not roll upside down and power stayed on.
Signal was lost at 15:32.2 with the drone almost into the water.

 

[Sam_B]

I appreciate your reply, and your diagnostic!

Have you watched the video footage, because it clearly shows the drone flipping upsidedown.

Here is a slowed down video:

CRASH (Slowed Down).mp4

MP4 File

1drv.ms

 

[Meta4]

Have you watched the video footage, because it clearly shows the drone flipping upsidedown.

Crash video can be confusing.
The data shows that the drone never rolled more than 73° to one side.
But the gimbal gets hung up when the drone rolls further than it can counteract and the view from the camera's perspective is what causes the confusion.

 

[Sam_B]

Ok.

I have just got my head around this:
DJI Flight Log Viewer - PhantomHelp.com

I understand what you are saying!


Any idea what caused this/if I could have done anything to stop it from happening/what I should do now (because obviously the drone is lost forever)??

 

[Deleted member 103366]

Any chance of you going fishing? How strong is the current in the river?

The DAT might have shown the motor speeds which would show if a motor jammed or slowed significantly or sped up if a prop blade came off.
The other logs were of no use to me sorry.

 

[Meta4]

Any idea what caused this/if I could have done anything to stop it from happening

The problem might have been impossible to identify before it happened.

 

[Sam_B]

The river is very murky, and the current is quite fast. I'm fairly certain it went straight down, but it would be too muddy, fast moving, and cold to retrieve it I think.

And even if I did find it, it would be destroyed from the water anyway!

 

[Deleted member 103366]

Fair enough. The reason for asking was, if you recovered the drone it might reveal a jammed motor or missing props etc, and there is a slim chance there might be a DAT on the memory card.

Do/did you sync your flight logs with DJI? If so it might be worth asking them if they have a copy of the DAT whose name ends FLY058.DAT

 

[Sam_B]

I'm not sure if I do. Is there a way to find out (like in the app or something)??

 

[Sam_B]

Is this what you mean?

 

[Deleted member 103366]

Yes that is what I mean and it looks like you do sync, they may have a copy of the DAT.