Mavic Air 2 Fall out of the sky. Why?

[flyacadia]

My Mavic air 2 quite literally few out of the sky. I did find the cached video of the last 15 seconds and I also have the "flight log?" if thats what its called. Received a motor unable to rotate error as the drone fell into the water. Any help?

 

[MAvic_South_Oz]

Welcome to the forum, all be it under such a circumstance.
Did you manage to recover the drone, or was it too difficult ?

Post the log or link to phantomhelp (or airdata) report.
You probably already have these, but just in case section 3 here . . .

Mavic Flight Log Retrieval and Analysis Guide

With the introduction of the Mavic Mini there has been a noticeable uptick in the number of posts requesting help with lost or crashed aircraft. While there is plenty of help and advice available on this forum, and detailed guidance and options on several other websites, I thought that perhaps a...

mavicpilots.com

The video (if you want to let the analytical minds and others see it) can be uploaded to YouTube or Vimeo etc, and the URL link placed directly here.

The cache video might be helpful, but probably just the flight log will do though.

 

[Wild Drone Pilot]

My Mavic air 2 quite literally few out of the sky. I did find the cached video of the last 15 seconds and I also have the "flight log?" if thats what its called. Received a motor unable to rotate error as the drone fell into the water. Any help?

My Air 2 yesterday was out over clear open air in sight and about 1,000 ft out kept loosing signal
Used to be much better range
Very disappointing DJI -- not Again!

 

[flyacadia]

Welcome to the forum, all be it under such a circumstance.
Did you manage to recover the drone, or was it too difficult ?

Post the log or link to phantomhelp (or airdata) report.
You probably already have these, but just in case section 3 here . . .

Mavic Flight Log Retrieval and Analysis Guide

With the introduction of the Mavic Mini there has been a noticeable uptick in the number of posts requesting help with lost or crashed aircraft. While there is plenty of help and advice available on this forum, and detailed guidance and options on several other websites, I thought that perhaps a...

mavicpilots.com

The video (if you want to let the analytical minds and others see it) can be uploaded to YouTube or Vimeo etc, and the URL link placed directly here.

The cache video might be helpful, but probably just the flight log will do though.

how do you find the flight log?

 

[flyacadia]

Here are two flight vids. One showing the cached video another showing map and controls/errors

Cached Video

Controller

 

[flyacadia]

I have gotten my money out of the drone though. I swapped props monthly due to my high use. I almost always only over water so I am pretty careful

 

[slup]

how do you find the flight log?

Go here --> DJI Flight Log Viewer | Phantom Help (scroll down a bit there & they describe where to find the logs stored in the mobile device you flew with)

Once retrieved & uploaded to above site they provide you with a link ... come back & share that here in a new post.

 

[flyacadia]

Flight Logs

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

 

[flyacadia]

Go here --> DJI Flight Log Viewer | Phantom Help (scroll down a bit there & they describe where to find the logs stored in the mobile device you flew with)

Once retrieved & uploaded to above site they provide you with a link ... come back & share that here in a new post.

DJI Flight Log Viewer - PhantomHelp.com

 

[Meta4]

Flight Logs

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

Things turned bad at around 8:15.8 when the drone started to roll to the right and pitch backwards.
In less than a second it had rolled upside down and was tumbling out of the sky.
This suggests a problem with the right rear motor or prop.

 

[flyacadia]

Things turned bad at around 8:15.8 when the drone started to roll to the right and pitch backwards.
In less than a second it had rolled upside down and was tumbling out of the sky.
This suggests a problem with the right rear motor or prop.

how common is it t for motors to fail? I change props every few months not because they show wear but just for preventative maintenance.

 

[MAvic_South_Oz]

how common is it t for motors to fail? I change props every few months not because they show wear but just for preventative maintenance.

Not often for motor failure, more so props from past episodes, though (I think) sometimes it's hard to determine without the DAT log . . . many DJI drones don't allow those to be viewed by anyone but DJI staff.

Prop changes so regularly can be an issue, there'd be more prop failures than motors I would think, and always a risk of damage when removing and replacing them.
I've had props on (never taken off) for up to 2 or so years, only replaced when upgrading (M1P OEM 8330 to MPP OEM 8331, then 8331 props to MAS Stealth), and only once more when I found some chips in a couple of the MAS, replaced the whole set for spare MAS.
This was over combined 5 years or so with that drone, I must still have 5 or 6 sets of the OEM prop versions.

Like you said, you got some good use from the Air 2, shame to lose it.

Do you have a back up, or will you buy another Air 2 and use with existing accessories ?

DJI might provide an aircraft only for a lower cost, though past reviews have shown you might be better getting a discounted Air 2 Flymore or single package now they are a little older.

Maybe sell your Air 2 stuff and get a later model drone is an option too, probably some pilots out there looking for extra Air 2 batteries, spare controller, etc.

 

[slup]

...This suggests a problem with the right rear motor or prop.

Yep ... it's pretty straight forward, this was a sudden thrust loss due to either a failing prop or motor.

But it most probably wasn't the right rear though ...

It's a bit difficult to exactly determine when it happens as all 4 stick commands was used there, all affecting the attitude of the craft in their own way... but it looks to be at 496,1sec into the flight where ...

-The craft suddenly, but shortly pitch down (green) even though the elevator is decreased (black dashed)
-The craft rolls (blue) over to the right side even though the aileron is decreased (green dashed)
-The craft starts to rotate CCW very much faster (purple) even though the rudder is held in a constant position.

It's very clear that the thrust loss is coming from the right side due to the roll direction. The craft also rotates CCW which suggests a thrust loss in a CW torquing corner (either front right or rear left) ... so it have to be a failing right front. This is confirmed shortly by the down pitch movement (green) where I have placed a red circle in the chart.

(Click on the chart to make it larger, values in the legend from 496,1sec where the chart marker is placed. Stick commands (dashed graphs) have value 1024 for neutral position.)

...sometimes it's hard to determine without the DAT log . . . many DJI drones don't allow those to be viewed by anyone but DJI staff.

When it comes to the Air 2 I believe the mobile device DAT log is readable for us ... @flyacadia , in the same place you found the TXT log you have a folder called MCDatFlightRecords. In there you should have a DAT log which ends with FLY009.DAT. Retrieve that & attach it to a new post if you want to know if this was a failing prop or motor.

 

[flyacadia]

looks like a small bird strike



amazing tools, thank you

I was looking right at the drone and didn't see any. It was likely a swallow and I would have been able to sea a gull

 

[slup]

looks like a small bird strike... I was looking right at the drone and didn't see any. It was likely a swallow and I would have been able to sea a gull

Unfortunately nothing in the TXT log makes either a prop or motor failure more or less likely ... only the DAT log can possibly give us that answer.

Below indication from the TXT log message stream is the only thing of value so far ... this message usually means what it says.



Try to retrieve the DAT log, then we will know more...

 

[flyacadia]

Unfortunately nothing in the TXT log makes either a prop or motor failure more or less likely ... only the DAT log can possibly give us that answer.

Below indication from the TXT log message stream is the only thing of value so far ... this message usually means what it says.

View attachment 146650

Try to retrieve the DAT log, then we will know more...

Mavic 2, Mavic Air, Air 2S, Mavic Mini, M300 RTK, and FPV drones DAT files extracted from the aircraft are not supported.

 

[BigAl07]

I have gotten my money out of the drone though. I swapped props monthly due to my high use. I almost always only over water so I am pretty carefulView attachment 146608

First off WELCOME to the forum. I wish it were under different conditions.

My personal thoughts on Prop Changes: Unless you have reason to believe there is a problem (visual, tactile, or otherwise) our props on these aircraft can last a VERY long time. I have flown for over 2 years on the "Factory" props and I would call myself a very Frequent Flyer. The more you "Swap Props" the more variables you're introducing and increasing your odds of a prop failure IMHO. If it's not broke no need to go fixing a problem you don't yet have.

So long as you aren't "impacting" anything with your props and you're not seeing any stress indicators you should be fine with running the props for many many hours. I'm NOT suggesting to not closely inspect your props before EVERY flight but I would not be replacing them just due to high time on them.

 

[slup]

Mavic 2, Mavic Air, Air 2S, Mavic Mini, M300 RTK, and FPV drones DAT files extracted from the aircraft are not supported.

What's needed is the Mobile device DAT log ... not the aircraft one. Read in the end of post #13.

 

[Deleted member 93449]

I have gotten my money out of the drone though. I swapped props monthly due to my high use. I almost always only over water so I am pretty carefulView attachment 146608

This (changing out props every month) could actually be the source of the problem. I don't know if there is a recommended time to prop replacement or its based on visual inspection but someone a lot smarted than I am and information about prop usage and failure could probably make some calculations regarding the chances of a prop failing over time versus an error occuring during the process of changing out props every month resulting in a failure.

 

[flyacadia]

Yep ... it's pretty straight forward, this was a sudden thrust loss due to either a failing prop or motor.

But it most probably wasn't the right rear though ...

It's a bit difficult to exactly determine when it happens as all 4 stick commands was used there, all affecting the attitude of the craft in their own way... but it looks to be at 496,1sec into the flight where ...

-The craft suddenly, but shortly pitch down (green) even though the elevator is decreased (black dashed)
-The craft rolls (blue) over to the right side even though the aileron is decreased (green dashed)
-The craft starts to rotate CCW very much faster (purple) even though the rudder is held in a constant position.

It's very clear that the thrust loss is coming from the right side due to the roll direction. The craft also rotates CCW which suggests a thrust loss in a CW torquing corner (either front right or rear left) ... so it have to be a failing right front. This is confirmed shortly by the down pitch movement (green) where I have placed a red circle in the chart.

(Click on the chart to make it larger, values in the legend from 496,1sec where the chart marker is placed. Stick commands (dashed graphs) have value 1024 for neutral position.)
View attachment 146643


When it comes to the Air 2 I believe the mobile device DAT log is readable for us ... @flyacadia , in the same place you found the TXT log you have a folder called MCDatFlightRecords. In there you should have a DAT log which ends with FLY009.DAT. Retrieve that & attach it to a new post if you want to know if this was a failing prop or motor.

I have not been able to find the DAT files for the MA2.I do not have a folder called MCDatFlightRecords