battery popping out during return to home and loosing connection

[jona2020]

Hey everyone, Im new to posting questions on forums but i had a situation with my Mavic Mini and would love to hear your thought.

I was flying my Mini on Vancouver island in the forest. Didn't fly to high or far and had great signal the whole time... wanted to test the return to home in a forest environment... as soon as i hit the button 5 seconds after i lost connection on the controller and didnt have a visual on phone. i assumed i would see the drone soon and be able to control it back home but that never happened... the connection never came back and i figured it hit a tree coming back or something. i went to use locate drone feature and it could not connect. I def had at least 15 min left on battery so even if it crashed i thought i would at least find it or hear the beeping...

I searched last location of gsp and nothing. A week went by and there was a storm and high winds and thought if the drone landed on a tree it might fall down and thankfully it did and i did retrieve it.... But the battery cover was open and the battery was missing... how could this happen and is this a defect.

I can understand if battery popped out when it fell from tree but i lost connection with drone very shortly after hitting return to home... weird..

thank for reading and any way this is a defect..

 

[slup]

Hi there & welcome to the forum ? , just a pity it's due to sad circumstances.

Start up with posting your mobile device TXT log, read up here on how to retrieve (under section 3.) --> Mavic Flight Log Retrieval and Analysis Guide

One possible scenario could have been that you lost the line of sight to the AC when the RTH had been initiated & the AC had started to come home ... & the lost connection was due to that, then later the AC crashed into a tree & the battery got thrown out in the impact.

 

[Deleted member 103366]

The battery certainly can come out in a crash, I have had it happen when my Mini was knocked off a low table onto the floor. If it happened in flight then I would guess it had not been properly inserted, there is no condemnation is saying that, we all make 'stupid' mistakes at times.
What height was the RTH height set too and was that below the tree tops from where the RTH was initiated i.e. could the drone have crashed into a tree because the RTH height was too low? Remember all heights are relative to the take off point and are not ground clearance.

If the battery did come out in flight then I imagine that the DAT flight log on the drone would stop suddenly with the drone in mid air. Unfortunately the DAT logs on the drone are, I believe, encrypted and from what I have seen yield no informataion when accessed, so that's a dead end.
However there may, note "may" be a log on the micro SD card that is of some use.

Hopefully you have not attempted to switch the drone on since the crash.
Remove the card from the mini and put it in a reader attached to a computer.
The following relates to a Windows machine but I assume there is a similar process on an Apple.
You need to switch off the "Hide extensions" feature and possibly switch on "show hidden folders".
Navigate to the folder "computer\card-name\MISC\LOG\flylog"....... in there there may be a file named "fc_log.log" . If so copy that file to your computer, DO NOT play with the original.

Working on the copy change the extension from ".log" to ".DAT", you will get one or more messages warning you that changing a file's type may render it useless etc. respond as necessary to change the extension. The ammended file can be opened using DatCon ( a piece of log reading software that is very useful and free) and outputs a .csv file which can, in turn, be opened as a spreadsheet and looks like a normal flight log.
Post a copy of the altered log i.e.fc_log.DAT, on here and one of the log CSI 'guys' (Slup, Sar104 et al) may investigate it. The log may contain nothing useful but then again it might

 

[BadWolf1]

As above, logs will give us something to go on, follow the the links @slup gave. The last few seconds of the log on the phone will either say everything was normal and the log stopped or an impact, or occasionally signs of a battery issue before total power failure.

Generally the mini doesn't have a problem with the battery coming out, and with the door closed if it comes unclipped it will remain inside the drone. Flying forwards, with the nose of the drone down, gravity is holding the battery in. It would take some kind of impact to knock the battery out. Crashing into / falling out of a tree would do it. It's unlikely that the battery was lost before impact; although it may still have caused the crash,

 

[Cw4bray]

You'd be really lucky if any impact didn't knock the battery out without adhesive tape over-the-door. I always use it. Instead of "find my drone" feature it should be "find my battery."