Mini 2 video interference leads to crash

[gwoods22]

Had an unfortunate crash this weekend and lost my DJI Mini 2 to the ocean. Didn't hit anything, it literally just fell out of the sky. This is the cached video from the app as I wasn't able to retrieve the drone.

About 5 seconds in to the video above you can see all these artifacts as the video quality degrades. It keeps getting worse and worse until it suddenly spirals to the ocean. Worth noting that the video quality seems to be restored on it's way down (around 0:40). So I'm wondering what happened to the video feed, why did it crash, and was it just a coincidence that both issues happened or is the cause linked? Anyone else seen anything like this happen?

I uploaded my flight log to phantomhelp which you can have a look at here if that would be helpful!

 

[sar104]

Can you retrieve the mobile device DAT file ending FLY098.DAT?

 

[gwoods22]

Can you retrieve the mobile device DAT file ending FLY098.DAT?

It seems the MCDatFlightRecords folder is now empty as the flight record has been uploaded to DJI servers. Is there anyway to retrieve the files once they've been uploaded?

 

[sar104]

It seems the MCDatFlightRecords folder is now empty as the flight record has been uploaded to DJI servers. Is there anyway to retrieve the files once they've been uploaded?

Unfortunately not. I would always recommend disabling log auto sync, because in the event of a problem the DAT file is by far the most useful source of data.

So based just on the TXT log attitude data it appears that the rear right motor seized. The eventual CW rotation is due to the angular imbalance of 2 CCW motors and only one CW motor operating. But note the initial CCW kick, which suggests that the motor stopped, rather than losing the prop. The motor data from the DAT file would have conclusively shown what happened. Also note a couple of precursor perturbations to pitch and roll in the second or so preceding the event.




Here's a view of the unwrapped yaw angle that makes the aircraft rotation easier to see, with the small initial CCW kick followed by steady CW rotation during the descent.



Just to forestall the inevitable rash of bird strike comments, I see no indication of an impact in the air. That should be a clear warranty issue. I'm not sure how the video artifacts might be related to the problem, but that is a strange coincidence.

 

[gwoods22]

Good news! I heard back from DJI and they confirmed this was a warranty issue which means a shiny new Mini 2 is on it's way! This was their response when asked about the cause of the incident:

"Based on the analysis result, it seems that the incident was caused by a possible power issue."​