uncontrolled crash

[Kakdog]

Hi everyone

On the weekend I was attempting to film a regional food and wine festival from the riverbank with my mavic air. I took off (after the system did a quick update of sorts but not the full update that I skipped over) from the riverbank deck under a restaurant and proceeded to fly up wind in line with the riverbank. About 20 seconds into the flight (hadn't even turned the camera on yet to record) my status went from green to yellow and changed to unctrl allt (or something very similar - guessing uncontrollable altitude?) and the drone turned around on its own accord and took off at full speed flying straight into the restaurant - which at near sunset was starting to fill up (you know everyone operators worst nightmare). Thankfully people saw it coming, got out of the way and it slammed into a wall hard enough to leave a mark in the wall, fully collapse the wings and rotors back in and the camera gimbal hanging out of the drone..

I talked to the videographers at the festival (I was primarily doing photography) who didn't recognise the error either but said the drone might have been thrown off by all the wifi use in the area (over a thousand people at the site plus a static wifi signal on the riverbank that the audio production team was also using) and didn't know what to do so just decided to go straight home which was under the restaurant.

Would love to know if anyone has any better ideas/thoughts on the matter - any assistance would be greatly appreciated

 

[mrreddog]

Maybe we can get @sar104 in here if you can download the datalogs, im not familar with the Mavic Air. So read up on how to post your logs, and just maybe some of these incredible data analyzers will chime in to help.

 

[Kakdog]

Thanks, I haven't even taken it back out of the case yet to inspect it after the crash lol

 

[sar104]

That sounds more like magnetic interference at takeoff rather than any kind of radio interference. The best way to see that is in the mobile device DAT file:

How to retrieve a V3.DAT from the tablet

 

[Kakdog]

I have the .dat files from my phone (android) - how do I read them? Lot of incomplete info online about it

 

[Simmo]

Upload them here and let Sar104 look at them. He has an excellant program (igor pro) to read the files.

 

[Meta4]

I have the .dat files from my phone (android) - how do I read them? Lot of incomplete info online about it

Or you could try going to DJI Flight Log Viewer - Phantom Help
Follow the instructions there to upload your flight record (it's a txt file) from your phone or tablet.
Come back and post a link to the report it provides.

But to cut to the chase ..
You said.. I took off from the riverbank deck
Was that a reinforced concrete structure?
Launching from reinforced concrete surfaces is a common cause for the symptoms you described.

 

[sar104]

I have the .dat files from my phone (android) - how do I read them? Lot of incomplete info online about it

The instructions are in the link above in post #4.

 

[Kakdog]

Yeah i can get the files but when i attach them in here it says unsupported file time

 

[Kakdog]

Being in a river bank there would be a decent amount of concrete underneath the structure from where i took off - timber deck with steel reinforcement and steel rails - the drone was above the water 60 meters away from the building (and any other structure) when the error occurred and it decided to take matters into its own hands

Or you could try going to DJI Flight Log Viewer - Phantom Help
Follow the instructions there to upload your flight record (it's a txt file) from your phone or tablet.
Come back and post a link to the report it provides.

But to cut to the chase ..
You said.. I took off from the riverbank deck
Was that a reinforced concrete structure?
Launching from reinforced concrete surfaces is a common cause for the symptoms you described.

 

[Meta4]

Being in a river bank there would be a decent amount of concrete underneath the structure from where i took off - timber deck with steel reinforcement and steel rails - the drone was above the water 60 meters away from the building (and any other structure) when the error occurred and it decided to take matters into its own hands

It's most likely that your flight was just one of hundreds that went bad because of launching from reinforced concrete or steel surfaces.
If you did supply your flight data as mentioned in post #7, it's probably going to show yaw and compass errors starting shortly after launching.

DJI really need to warn users to avoid launching from steel or reinforced concrete surfaces.

 

[Kakdog]

It's most likely that your flight was just one of hundreds that went bad because of launching from reinforced concrete or steel surfaces.
If you did supply your flight data as mentioned in post #7, it's probably going to show yaw and compass errors starting shortly after launching.

once i stop being a noob and figure out how to post them i will..

im also assuming dji would consider the incident complete operator error and not fix it without payment and the extended warranty (additional one year) from the retailer would be the same

 

[Meta4]

once i stop being a noon and figure out how to post them i will

There are instructions if you go to the link I provided.
It only takes a minute or two.

 

[sar104]

Yeah i can get the files but when i attach them in here it says unsupported file time

Just change the file extension from .DAT to .txt and then they will upload.

 

[Kakdog]

right.. still noobing.. is that readable?

 

[Goof]

Aren't mavic 2 and mavic air files encrypted? I've been trying to open my own .DATs for interest's sake but DatCon won't have a bar of it >_<

 

[sar104]

right.. still noobing.. is that readable?

It looks like a DAT file but, for some reason, I cannot read it. @BudWalker?

 

[sar104]

Aren't mavic 2 and mavic air files encrypted? I've been trying to open my own .DATs for interest's sake but DatCon won't have a bar of it >_<

The aircraft files are encrypted differently and DatCon currently won't read them, but the mobile device DAT files are readable.

 

[ac0j]

Didn’t finish the update and skipped over some of it?
Was it firmware or software?
Not that it matters but that was probably a mistake You should reboot the AC if it updates before you fly. And you should restart the app if it updates. But I am thinking bad compass reading is the issue here. Sounds familiar

 

[BudWalker]

right.. still noobing.. is that readable?

There is something odd about the file you submitted. Did you open the .DAT in an editor and then save it as a .txt? If so, the procedure you want to use is to direct the File Manager to change the extension from a .DAT to a .txt.