Mavic pro went crazy, unable control and crash.

[xxtomixx1]

Hi everyone.
I was flying yesterday until Mavic starts to behave abnormally and finally it crashed. Can anyone have look at DAT file and help me figure out what exactly happened?
The whole flight went well, when the drone was high something starts to happen, drone start to circulate and finally fell down.

There is a link to video recorded just before the crash:

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FLY DAT file uploaded there:

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Thank you for help.

 

[Meta4]

I was flying yesterday until Mavic starts to behave abnormally and finally it crashed. Can anyone have look at DAT file and help me figure out what exactly happened?

Can you post the .txt file?

 

[SmilingOgre]

Hi everyone.
I was flying yesterday until Mavic starts to behave abnormally and finally it crashed. Can anyone have look at DAT file and help me figure out what exactly happened?
The whole flight went well, when the drone was high something starts to happen, drone start to circulate and finally fell down.

There is a link to video recorded just before the crash:

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

FLY DAT file uploaded there:

Gofile - Cloud Storage Made Simple

Secure, fast and free cloud storage solution. Upload and share files instantly.

gofile.io

Thank you for help.

Please excuse the interruption, I'm just commenting to follow this thread. Mine is headed back to DJI for repair today.

 

[xxtomixx1]

Hi, I've launched from the playing fields, grass surface, I don't experience any interferences when lunching

 

[Meta4]

Hi, I've launched from the playing fields, grass surface, I don't experience any interferences when lunching

Your flight looks like this: DJI Flight Log Viewer - PhantomHelp.com

You had hardware errors affecting that flight.
The flight data is peppered with Speed Errors.
At 3:32.2 you initiated RTH and the drone started to turn to face home, but kept turning anti-clockwise without any joystick input.

At around 3:40.6 the drone started losing height as it was spinning.
Applying positive throttle failed to stop the descent and pushing the left stick to the right failed to stop the anti-clockwise spinning and the drone came down.

Some compass errors late in the flight data are due to the fast spinning and are not indicating anything that caused any problem.

 

[xxtomixx1]

Your flight looks like this: DJI Flight Log Viewer - PhantomHelp.com

You had hardware errors affecting that flight.
The flight data is peppered with Speed Errors.
At 3:32.2 you initiated RTH and the drone started to turn to face home, but kept turning anti-clockwise without any joystick input.

At around 3:40.6 the drone started losing height as it was spinning.
Applying positive throttle failed to stop the descent and pushing the left stick to the right failed to stop the anti-clockwise spinning and the drone came down.

Some compass errors late in the flight data are due to the fast spinning and are not indicating anything that caused any problem.

Hi Meta4, thank you for your quick response.

What kinda hardware error we are talking about? What does mean Speed error or what can cause it? Is it possible that one of the propellers broke during the flight? I can not see an immediate speed increase of one of the motors in case of props gone.

 

[Meta4]

Hi Meta4, thank you for your quick response.

What kinda hardware error we are talking about? What does mean Speed error or what can cause it? Is it possible that one of the propellers broke during the flight? I can not see an immediate speed increase of one of the motors in case of props gone.

I'm not certain but I think a speed error is the flight controller advising that the speed indicated by the IMU sensors disagrees with the Speed from GPS.
It looks like a failure of the IMU was the cause of the incident.

 

[xxtomixx1]

There are few lines from .DAT file when it starts to be faulty:


182.585 : [L-MIS][SDK]reset user_emergency_brake by ctrl dev changing
186.306 : [L-FDI][CTRL]: fault on , horiz_ctrl_fail
186.328 : [L-FDI][CTRL]: fault off, horiz_ctrl_fail
188.206 : [L-FDI][CTRL]: fault on , horiz_ctrl_fail
188.645 : [L-FMU/LED]action changed. aircraft install warning!:aircraft vibration err(3)
199.727 : [L-NS][AHRS] yaw aligned 0
200.906 : [L-FDI][CTRL]: fault off, horiz_ctrl_fail
211.905 : [L-RC]rc cmd:STD_GO_HOME
211.945 : [L-FLYMODE][Ctrl<7>] REQ_RC_GO_HOME NAVI_GO_HOME ctrl_navi_go_home
215.306 : [L-FDI][CTRL]: fault on , horiz_ctrl_fail
220.065 : [L-FLYMODE][ACT.msg] ACT_GO_HOME torsion sat protect!
220.225 : [L-FDI][CTRL]: fault on , head_ctrl_fail
220.486 : [L-FDI][CTRL]: fault on , tilt_ctrl_fail
220.505 : [L-RC]craft ctrl failed!!!
220.506 : [L-FDI][CTRL]: fault off, horiz_ctrl_fail
220.625 : [L-FDI][CTRL]: fault off, tilt_ctrl_fail
221.128 : [L-FDI][CTRL]: fault on , tilt_ctrl_fail
221.265 : [L-FDI][CTRL]: fault off, tilt_ctrl_fail
221.327 : [L-NS] [AHRS] gyro mag inconsist on
221.525 : [L-FDI][CTRL]: fault off, head_ctrl_fail
222.206 : [L-FDI][CTRL]: fault on , tilt_ctrl_fail
222.264 : [L-FMU/FSM]near ground
222.446 : [L-FDI][CTRL]: fault off, tilt_ctrl_fail
222.525 : [L-RC]craft ctrl failed!!!

Can someone confirm IMU failure? What I should replace/repair in that case?

 

[xxtomixx1]

 

[xxtomixx1]

It doesn't look like very high wind caused this issue either.

 

[Meta4]

It doesn't look like very high wind caused this issue either.

A high wind is never going to cause a spiralling uncommanded descent.

 

[Sputterwall]

I suggested in your other thread about this incident that it looks misty in the video, and I am wondering if moisture could be the culprit here. I still think that after reading through this thread, and I also found the following statements in this thread, post #6:

" Yes when water get inside the battery , the Flip over to death valley is quick not because the battery is dead but because it lost it ability to connect with the drone and than the drone just flips over and drops. The Battery is as we state the weak link because of the disconnect that happens like this even though the battery is still itself working.

Your mistake was attempting to start up the drone with the same battery that compromised and most likely shorting out the IMU board. "

This came from a member who is very familiar with such issues.

 

[BudWalker]

Hi everyone.
I was flying yesterday until Mavic starts to behave abnormally and finally it crashed. Can anyone have look at DAT file and help me figure out what exactly happened?
The whole flight went well, when the drone was high something starts to happen, drone start to circulate and finally fell down.

There is a link to video recorded just before the crash:

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

FLY DAT file uploaded there:

Gofile - Cloud Storage Made Simple

Secure, fast and free cloud storage solution. Upload and share files instantly.

gofile.io

Thank you for help.

This one is unusual. At about 184 secs leftBack started being commanded 100% and drawing much more current. The gyros became quite noisy. The MP was still being controlled, although somewhat unstable. This all suggests part of the leftBack prop broke loose.


And, from the eventLog stream
188.206 : 10639 [L-FDI][CTRL]: fault on , horiz_ctrl_fail
188.645 : 10661 [L-FMU/LED]action changed. aircraft install warning!:aircraft vibration err(3)

This went on until about 218 secs where it looks like the rightFront completely lost propulsion. It began to tumble pitch down, roll CW and yawing CW - all consistent with loss of rightFront propulsion.

It was at this point the MP began it's uncontrolled descent.

I'm assuming the vibration caused the rightFront prop/motor problem.

@xxtomixx1 what was the condition of the props?

 

[xxtomixx1]

Thank you @BudWalker for your involvement. You made a very good point. Props were kind overall good condition, co cracks or missing bits on them.

What I'm thinking(correct me if I'm wrong, please) is when prop will brake - motor speed should immediately increase due to lower resistance for the motor to spin, in that case, I can only see small about 1500 rpm? speed increase with PWM on 100 and massive current increase from 2 to 9. What telling me there may be some issue with motor (something gets inside? motor seized?) and caused some resistance what immediately kicks up the motor current.
But in that case scenario there should be some motor blockage warning I guess.

At the moment MP is flying, can not see any issues with the motors, they spinning without resistance. Obviously there is no video and gimbal flex gone
Again I'm not a specialist and a scientist or physicist, so correct me guys if the way of my thinking is wrong.
Thank you aff for your effort and help.

 

[xxtomixx1]

I suggested in your other thread about this incident that it looks misty in the video, and I am wondering if moisture could be the culprit here. I still think that after reading through this thread, and I also found the following statements in this thread, post #6:

" Yes when water get inside the battery , the Flip over to death valley is quick not because the battery is dead but because it lost it ability to connect with the drone and than the drone just flips over and drops. The Battery is as we state the weak link because of the disconnect that happens like this even though the battery is still itself working.

Your mistake was attempting to start up the drone with the same battery that compromised and most likely shorting out the IMU board. "

This came from a member who is very familiar with such issues.

Hi @Sputterwall, thanks for a suggestion and your involvement at the case. There was a very warm day without any rain or mist or any moisture in the air so I doubt that was the reason of the crash.

 

[BudWalker]

Thank you @BudWalker for your involvement. You made a very good point. Props were kind overall good condition, co cracks or missing bits on them.

What I'm thinking(correct me if I'm wrong, please) is when prop will brake - motor speed should immediately increase due to lower resistance for the motor to spin, in that case, I can only see small about 1500 rpm? speed increase with PWM on 100 and massive current increase from 2 to 9. What telling me there may be some issue with motor (something gets inside? motor seized?) and caused some resistance what immediately kicks up the motor current.
But in that case scenario there should be some motor blockage warning I guess.

At the moment MP is flying, can not see any issues with the motors, they spinning without resistance. Obviously there is no video and gimbal flex gone
Again I'm not a specialist and a scientist or physicist, so correct me guys if the way of my thinking is wrong.
Thank you aff for your effort and help.

View attachment 113538

That's right. The data starting at 184 secs is indicative of a motor problem. Not a prop issue as I was thinking. The lack of a motor blockage isn't too concerning as it appears there was only a partial problem.

Also, I looked a little closer at the data starting at 218 secs. As I had said the integrated gyro data shows tumbling in a way that is consistent with loosing rightFront propulsion. The motor data shows the rightFront (red) and leftBack (black) each being commanded to 100% but out of phase. In addition, the angular vibration changes at this point.

I had supposed that the rightFront had developed a propulsion problem. I think it's more likely that the leftBack motor issue became worse. What followed were the oscillations seen above where 1) the FC would lower the rightFront speed to compensate for the leftBack propulsion loss, and then 2) the correction was too much and the FC would have to reverse those inputs.

Just my theory..... i.e., my theory for now.

 

[xxtomixx1]

That's right. The data starting at 184 secs is indicative of a motor problem. Not a prop issue as I was thinking. The lack of a motor blockage isn't too concerning as it appears there was only a partial problem.

Also, I looked a little closer at the data starting at 218 secs. As I had said the integrated gyro data shows tumbling in a way that is consistent with loosing rightFront propulsion. The motor data shows the rightFront (red) and leftBack (black) each being commanded to 100% but out of phase. In addition, the angular vibration changes at this point.
View attachment 113560
I had supposed that the rightFront had developed a propulsion problem. I think it's more likely that the leftBack motor issue became worse. What followed were the oscillations seen above where 1) the FC would lower the rightFront speed to compensate for the leftBack propulsion loss, and then 2) the correction was too much and the FC would have to reverse those inputs.

Just my theory..... i.e., my theory for now.

Thanks @BudWalker for deap reaserch and your time.
I can't remember what state were props after crash, I belive rear ones were missing and some prices were around MP, one side of the front one was still attached. I'll will try to fix it and test it hovering on lov altitiude for safety. I have to admire I'm not trusting this things anymore.

Anyway great forum with loads of kind and experienced pilots. Thank you.

 

[BudWalker]

Thanks @BudWalker for deap reaserch and your time.
I can't remember what state were props after crash, I belive rear ones were missing and some prices were around MP, one side of the front one was still attached. I'll will try to fix it and test it hovering on lov altitiude for safety. I have to admire I'm not trusting this things anymore.

Anyway great forum with loads of kind and experienced pilots. Thank you.

But, you had said
"Props were kind overall good condition, co cracks or missing bits on them. "

 

[xxtomixx1]

But, you had said
"Props were kind overall good condition, co cracks or missing bits on them. "

Yes, before crash.

 

[DagDerniT]

Did you lose a prop or was one damaged? Looks like a prop came off and caused the drone to lose control and of course crash.