Finally crashed after new update

[bmwbob]

DJI Mavic Air 2 having flown for many miles with no issues. Downloaded update today and took off per normal and flew around my normal haunts over dry riverbed. I hit go home at 300 feet in the air about quarter mile from the house. Drone responded normally and about 200 yards for the house it disconnected without warning a crashed in a neighbors yard. I was able to use the find my drone app to find it, but it's pretty beat up and camera is broken. I'll call DJI tomorrow, but never a problem with approximately 700 miles flying until new updat!

 

[Rchawks]

Crashing always sucks. Sorry to hear about your drone. I haven't updated lately because my ma2 and mm have handed so well and several people have stated they crashed after an update. I don't know, the tech stuff is above my skill level.

 

[Meta4]

Drone responded normally and about 200 yards for the house it disconnected without warning a crashed in a neighbors yard.

That sounds like a case of total loss of power, which causes the drone to fall from the sky and a disconnected message shows on your screen.
Simply disconnecting is no problem and only initiates RTH.

... but never a problem with approximately 700 miles flying until new update!

It will be a coincidence that the incident happened after an update.

 

[Gagey52]

Would it help to recover the flight logs if possible.
Regards

 

[MAvic_South_Oz]

Would it help to recover the flight logs if possible.
Regards

Yes, it probably would . . .

If you want to get to the bottom of this, find and post your flight TXT log, either the TXT file itself from the device folder, or post it into phantomhelp flight programme online and post the link to that report back up here.

All explained in section 3 of this post . . .

Mavic Flight Log Retrieval and Analysis Guide​

 

[Meta4]

Would it help to recover the flight logs if possible.

Maybe, but probably not.
If it was 300 ft up, crashing with an obstacle or flying behind an obstacle are unlikely causes of disconnection.
If it was a power loss, the data will just end with the drone in stable flight.

 

[bmwbob]

It just disconnected after some power messages during RTH.

 

[tlswift58]

It just disconnected after some power messages during RTH.

Power Messages? Landing battery % - 1%. That seems to be the issue right there. Started out with only 83% battery, so 15 minutes would be getting close to max flight time - which also would depend on whether you were flying in Sport / Normal, wind speeds at altitude and were you flying home in a headwind.

One reason I do not use RTH is it makes people complacent and they just expect the drone to come home with no issues. 75% time - yes. Yet, again with super low battery and maybe a headwind fighting against - 300 feet is not the place to be. 100-150 foot would have been a better altitude to clear any trees and not fight any wind with low battery.

 

[Paint Rock Drones]

If I'm reading correctly, the last record before the crash shows battery at 1%. Doesn't that support the idea that the loss of signal and crash was caused by an abrupt loss of power?

 

[hiflyer201]

Strange notifications @6 min. it showed 48%battery then after being in sport mode for about 6 min longer it showed 48% battery. That was after being in RTH mode which I assume returned to normal mode. It shows it landed with 1% battery. What am I missing? what do you have your RTH set at? I have mine set at 30% and I get a lot of warnings..I have to admit I haven't experimented with changing it.
Really sorry to hear about your loss..I enjoy your videos.

 

[GFields]

So sorry for your loss. I've been there!

 

[MAvic_South_Oz]

Here it is on PhantomHelp . . .

DJI Flight Log Viewer - PhantomHelp.com

All stick inputs appeared to match flight.
Perfectly.

Nothing untoward apart from brief disconnect at 5:49, 2700' out, can happen, nd then massive cell deviation at 6:24 which didn't appear to affect things too much.

You used active track quite a bit up at 220' alt, a couple of times between sports mode, do you recall actually doing that ?
Not much you can track up there.

Battery levels, yeah, very odd.
Took off and stayed at 83% for 6:41, then drops to 50%, stayed around there until much later in flight.
1x power load max warning in sports and climbing, expected as much of the flight was in sports mode.

The oddest thing, 11:24 you are a street or so from home, 416', and then you flew full right stick for 1 minute away out to 3516' until you hit RTH.
Then it stayed at 400' as you were above the set 144' RTH alt.

200 yards out your battery failed due to total loss of power, didn't seem to even go to auto landing, just stopped dead in the air and fell.

Maybe the proper analysts (unlike me ha ha) can look further with the CSV programme and see what else can be found.

It's possible due to failed auto landing DJI MIGHT cover something for you, even a discounted new aircraft and battery.

Lessons to learn here for sure, hope it's not to bad a repair cost, or maybe pick up a 2nd hand A2.

 

[Meta4]

It shows it landed with 1% battery.

The last line of data is false data.
The last line of real data has the drone 400 ft up, returning at 21 mph with the battery at 48%.
The pitch, roll and yaw data indicate the drone in stable flight without anything to suggest a cause of the incident.
That's what a total sudden loss of power looks like in flight data.

 

[slup]

Something really wonky is going on with that batteries BMS chip ...

Just looking at the individual cell voltages & the battery percentage makes you draw wrong conclusions ... the battery wasn't at 83% at take-off & it wasn't at 48% when the log ends either.

Looking at the total battery voltage shows another picture ... it had 12,36v at take-off & that average down to 4,12v/cell... ie. full. And it had 10,51v when the log ends ... which is 3,503v/cell, ie. a very low battery percentage, between 5 to 0% perhaps.



With this low battery percentage it's strange that no low battery auto landing was initiated which was defined as 12% there in the end of the log.

My guess is that the BMS in this battery wasn't healthy ... reporting wrong data back to the flight controller making it believe everything was good to go & it wasn't any need for either low battery RTH or landing ... instead it went to 0% & dropped dead.

Would be interesting to hear what DJI have to say about this ...

 

[Rchawks]

Man, you guys are good!

 

[eEridani]

This message evades me: except perhaps extremely low voltage, perhaps a mid-air strike with something. But Airdata is reporting normal levels, PhantomHelp, not so much.

Vision sensor(s) blocked. Fly with caution (Code: 180038). Vision sensor(s) blocked. Fly with caution (Code: 720152)

 

[bmwbob]

The battery level looked stuck at 48% and felt something was off and hit RTH then I got a vision sensor warning and disconnected when it was almost home. I have 700 miles on this drone with no issues of any sort (till software update)! We'll see what DJI has to say. When I told DJI had a vision sensor error it seemed to be a warranty issue as it's still in warranty period!

 

[Meta4]

This message evades me: except perhaps extremely low voltage, perhaps a mid-air strike with something. But Airdata is reporting normal levels, PhantomHelp, not so much.

Vision sensor(s) blocked. Fly with caution (Code: 180038). Vision sensor(s) blocked. Fly with caution (Code: 720152)

There's nothing abnormal about the way Phantomhelp is showing the VPS information.
It showed normally at the start from 1 ft to 40 ft and showed nothing after that as the drone was too high for VPS.
Phantomhelp indicates no VPS error, and definitely no mid-air collision.

 

[RFo]

Something really wonky is going on with that batteries BMS chip ...

Just looking at the individual cell voltages & the battery percentage makes you draw wrong conclusions ... the battery wasn't at 83% at take-off & it wasn't at 48% when the log ends either.

Looking at the total battery voltage shows another picture ... it had 12,36v at take-off & that average down to 4,12v/cell... ie. full. And it had 10,51v when the log ends ... which is 3,503v/cell, ie. a very low battery percentage, between 5 to 0% perhaps.

View attachment 136612

With this low battery percentage it's strange that no low battery auto landing was initiated which was defined as 12% there in the end of the log.

My guess is that the BMS in this battery wasn't healthy ... reporting wrong data back to the flight controller making it believe everything was good to go & it wasn't any need for either low battery RTH or landing ... instead it went to 0% & dropped dead.

Would be interesting to hear what DJI have to say about this ...

witch program you use for this analyses

 

[slup]

witch program you use for this analyses

CsvView --> CsvView Introduction