Hi All

My Mavic Mini also flew off.

I had 4 minutes flight time total, in 3 flights. I had done the update that was avaliable after the first flight. I was trying to learn the controls and the screen, it was showing a gimbal error which i had landed just before this flight to make sure nothing was stuck in it as i had removed the tape that had held it with the packaging. anyway

The drone was about 9m above me when it veered up and to the left, i react by trying to pull it back down towards me but the controls didnt work, i then pressed up to try and get it to clear the trees it was heading for... it hit a tree. The gimbal is out and a lead to the camera is severed.

Where do i stand with this as it was only purchased a few hours previously, take it back to the shop or what

Hopefully attached are the flight logs

https://www.phantomhelp.com/LogViewer/EBIMB4Q89MCCAUBZVJZQ

Regards

M

Hey fella.

Welcome to the forum.


The first thing I see here is that have taken off without a gps signal.  It is recommended to have 12 or more locks before taking g to the air.  


I’m sure the more technical guys and girls on the forum will tell you more.  

Wish you all the best, and a good resolution.

I'm a newbie myself but I also see the same thing as urbanweb. I'm not sure if this would be covered or not since the proper instructions were not followed for safe flight. More experienced folks here would know. However, my advice is to read the manual and follow it. Never take off without GPS lock unless you are flying inside where GPS is not available.

Like most reported "fly away" incidents, your drone did not "fly away".
You were impatient and launched before getting good GPS position information and your drone recording a home point.
You flew for 1:04.9 before the drone was able to record a home point.
That home point is going to be some distance from where you launched.

You also have a second problem that's worse.
It looks like you launched from close to something made of steel and gave your drone a Yaw Error.
Once you gained GPS and flew forward, because of the yaw error the drone thought it had drifted away from where it should be and tried to correct position.
But because of the yaw error, it got further away and corrected more, increasing speed as it went despite you being hands off on the controls.

Labroides Posted at 12-28 17:55
Like most reported "fly away" incidents, your drone did not "fly away".
You were impatient and launched before getting good GPS position information and your drone recording a home point.
You flew for 1:04.9 before the drone was able to record a home point.

I don't think that's the full story, reading his log he never made stick input after taking off and only after it received gps lock do I see any input. I uploaded his flight to my airdata to view wind information and the ground wind was 15mph, I took a look at ventusky and the winds at his location was above 20mph for time of flight.

Knowing the wind information and the fact he didn't have gps lock it looks to me like the drone was carried a good distance by the wind before obtaining gps lock, responded to user input but was fighting the wind. The drone yaw's right and proceeds to accelerate to above 30mph and disconnects after hitting the trees.

ABeardedItalian Posted at 12-28 18:10
I don't think that's the full story, reading his log he never made stick input after taking off and only after it received gps lock do I see any input. I uploaded his flight to my airdata to view wind information and the ground wind was 15mph, I took a look at ventusky and the winds at his location was above 20mph for time of flight.

Knowing the wind information and the fact he didn't have gps lock it looks to me like the drone was carried a good distance by the wind before obtaining gps lock, responded to user input but was fighting the wind. The drone yaw's right and proceeds to accelerate to above 30mph and disconnects after hitting the trees.

Do you also note my height was 20 ft and that I didn't travel away from myself, there was little wind at the time and it shows 12 satellites connect at the time it did this yaw maneuver. I explained I was hovering and becoming accustomed to it. Also I was no where near any steel structures

padstone Posted at 12-28 18:25
Do you also note my height was 20 ft and that I didn't travel away from myself, there was little wind at the time and it shows 12 satellites connect at the time it did this yaw maneuver. I explained I was hovering and becoming accustomed to it. Also I was no where near any steel structures

Also it reported no yaw error just a gimble error

urbanweb Posted at 12-28 16:46
Hey fella.

Welcome to the forum.

Thanks for this, there were 12 satellites connect when it took off on me

ABeardedItalian Posted at 12-28 18:10
I don't think that's the full story, reading his log he never made stick input after taking off and only after it received gps lock do I see any input. I uploaded his flight to my airdata to view wind information and the ground wind was 15mph, I took a look at ventusky and the winds at his location was above 20mph for time of flight.

Knowing the wind information and the fact he didn't have gps lock it looks to me like the drone was carried a good distance by the wind before obtaining gps lock, responded to user input but was fighting the wind. The drone yaw's right and proceeds to accelerate to above 30mph and disconnects after hitting the trees.

I don't think that's the full story, reading his log he never made stick input after taking off and only after it received gps lock do I see any input.
Look again, there's plenty of stick input during the time before the home point was recorded.
He was actively climbing and flying the drone most of that time.

Knowing the wind information and the fact he didn't have gps lock it looks to me like the drone was carried a good distance by the wind before obtaining gps lock, responded to user input but was fighting the wind.
While flying without GPS there may have been some wind drift but once GPS was gained the drone was easily able to hold position.
See from 1:07.1 when the speed is zero with hands off the controls.
No sign of any wind drift or problem holding position there.

The drone yaw's right and proceeds to accelerate to above 30mph and disconnects after hitting the trees.
That's a classic indication of a Yaw Error situation which the drone would not be able to respond to until it had GPS.

urbanweb Posted at 12-28 16:46
Hey fella.

Welcome to the forum.

Yes I have looked at the flight logs and love your idea of 12 sats before flight.

padstone Posted at 12-28 18:32
Thanks for this, there were 12 satellites connect when it took off on me

Not when you took off though.  This is important.

grahamjohnson10 Posted at 12-28 18:41
Yes I have looked at the flight logs and love your idea of 12 sats before flight.

It does make sense! Thank you

padstone Posted at 12-28 18:27
Also it reported no yaw error just a gimble error

The yaw error message does not show up in Mavic Mini flight data but the data does confirm this is the issue.
A yaw error can't cause problems until the drone has GPS and is able to correct any drift.
unfortunately the correcting will set the drone further away which it tries to correct, putting it even further away etc, etc.
It quickly gains speed without any joystick input.
Also I was no where near any steel structures
The issue is caused by magnetic fields where you launch.
The most common one is from launching from a reinforced concrete surface.
Otherwise it could be from a wooden deck or table with steel bolts or frames that were close to the compass etc.

urbanweb Posted at 12-28 18:52
Not when you took off though.  This is important.

Hi, I'm sorry for the confusion in what I wrote. When I said it took off on me, I meant when it pulled this yaw error. However on looking again there were 9.
Yes I see I made an error in taking off without enough satellite signal, however I thought it had signal at the time looking at the display.
Also why does it show the Home location differently on this data than on the flight logs from the dji app, which shows it directly where I was, which was what It showed me at the time.
I did not take off from a reinforced concrete structure nor am I in the vicinity of one.
It was a 2" or 50mm slab of concrete
I thank some of you for taking the time to help me, and to those who are trying to discredit me as not telling the whole story etc, I have been completely open from the beginning. Long story short, I am not a liar.
It was giving me no indications that this was about to happen, no warnings that I was doing something wrong.
Thanks

Labroides Posted at 12-28 20:14
The yaw error message does not show up in Mavic Mini flight data but the data does confirm this is the issue.
A yaw error can't cause problems until the drone has GPS and is able to correct any drift.
unfortunately the correcting will set the drone further away which it tries to correct, putting it even further away etc, etc.

Can you help me understand "what happened when" based on the MAP route displayed?  I'm not sure I'm following you that a yaw error coupled with obtaining a GPS lock will cause a rapid change in position while ignoring pilot inputs.

Minnesota Posted at 12-29 01:33
Can you help me understand "what happened when" based on the MAP route displayed?  I'm not sure I'm following you that a yaw error coupled with obtaining a GPS lock will cause a rapid change in position while ignoring pilot inputs.

It's complicated to explain.
Without GPS, the yaw error has no effect on the drone because it can't detect that it has moved and can't make any correction.
But when the drone gets GPS the yaw error has it's usual effect as seen by what your drone did.

Labroides Posted at 12-28 18:36
I don't think that's the full story, reading his log he never made stick input after taking off and only after it received gps lock do I see any input.
Look again, there's plenty of stick input during the time before the home point was recorded.
He was actively climbing and flying the drone most of that time.

Thanks for your comment, I'm going to post some pics of the drone, as there is little damage done, but there is a ribbon cable that was torn when I recovered it but has since torn off completely due to me handling the drone. Is this the cause of the gimbal error prior to crash? I can post the other 2 flight logs if needed. Does the gimbal provide equilibrium sort of flying data to the drone, giving cause to this yaw thing?

Labroides Posted at 12-29 02:07
It's complicated to explain.
Without GPS, the yaw error has no effect on the drone because it can't detect that it has moved and can't make any correction.
But when the drone gets GPS the yaw error has it's usual effect as seen by what your drone did.

Here's the replay (slowed down at the critical part).  Seems to support the OP's claim of a Fly Away.  At first I thought he may have been on Mode 1 but both the speed and altitude ramped with only input on one stick (if we can trust the stick graphics).  Comments?

Minnesota Posted at 12-29 01:33
Can you help me understand "what happened when" based on the MAP route displayed?  I'm not sure I'm following you that a yaw error coupled with obtaining a GPS lock will cause a rapid change in position while ignoring pilot inputs.

Thanks Minnesota.
The map that has been generated shows the Home point about 100 yards away, thus is incorrect and I didn't fly it far from me, about 6m up and 6m away from me, there was little to no drift with wind. My stick inputs will back this up. It shows on my dji log that home is where I was and that's what it showed on my screen at the time.
I just want it fixed and am trying to work out what went wrong. You say I shouldn't fly it without GPS unless I'm inside, however it had 9 Sat's and only picked up 12 as it was crashing. I realise I took off without GPS and have learnt from this the hard way but I'm not getting a explanation as to why it yawed. It was just beside me when this happened

Hi M,

had a look at your flightlog and have a question.

Do you know wich way your MM was on the groud, the heading approx?

cheers
JJB

Minnesota Posted at 12-29 03:17
Here's the replay (slowed down at the critical part).  Seems to support the OP's claim of a Fly Away.  At first I thought he may have been on Mode 1 but both the speed and altitude ramped with only input on one stick (if we can trust the stick graphics).  Comments?

https://youtu.be/GSPScQfMhHY

I pulled down and to the left on the left stick as it did this yaw thing, to try and get it back to me as a reflex, then I let go of the sticks but it kept going,. I then pushed up on the stick as I new it was heading for those trees and was trying in vein to clear them, hoping it would come to its senses and come back home if it didn't hit anything. I know I'm going on about this a bit but I want to get it fixed, this ribbon doesn't seem to be a big deal, but is there something wrong with the drone from factory and this will happen again, do I launch a case with dji or is this more hassle than its worth? Others on this forum don't seem to be getting on so well

Regards m

padstone Posted at 12-29 03:20
Thanks Minnesota.
The map that has been generated shows the Home point about 100 yards away, thus is incorrect and I didn't fly it far from me, about 6m up and 6m away from me, there was little to no drift with wind. My stick inputs will back this up. It shows on my dji log that home is where I was and that's what it showed on my screen at the time.
I just want it fixed and am trying to work out what went wrong. You say I shouldn't fly it without GPS unless I'm inside, however it had 9 Sat's and only picked up 12 as it was crashing. I realise I took off without GPS and have learnt from this the hard way but I'm not getting a explanation as to why it yawed. It was just beside me when this happened

Were you recording video?  If so there should be some evidence on your phone of which way the MM was facing when you were hovering.

JJB* Posted at 12-29 03:20
Hi M,

had a look at your flightlog and have a question.

Hi jjb.
Do you mean what direction it was facing on the compass when I launched it or what direction it was hovering in when it pulled the maneuver.
I'll guess hovering and it would be west, but I can get you more accurate coordinates and direction if you need them. Was dying to get flying this thing today

Minnesota Posted at 12-29 03:31
Were you recording video?  If so there should be some evidence on your phone of which way the MM was facing when you were hovering.

Sorry I didn't have a card in at the time, that would have been my trip this morning to get one. I had originally thought it would record to my phone, as I say new to this, but was working most of yesterday

padstone Posted at 12-29 03:34
Hi jjb.
Do you mean what direction it was facing on the compass when I launched it or what direction it was hovering in when it pulled the maneuver.
I'll guess hovering and it would be west, but I can get you more accurate coordinates and direction if you need them. Was dying to get flying this thing today

Hi padstone,

yes i mean the craft direction (nose to hdg?) on the ground, so the actual heading of the craft as using a manual handheld compass.
Do you use mode2 for the RC sticks?

Puzzled by your log, see my chart.

When i flew away the heading of the drone and moving direction are the same, with forward speed that means craft pitches down.
But the data shows that nose is UP! Hmm, means that craft is flying backwards. see my chart.

This expains the fly away because the compass was indication the wrong heading.

cheers
JJB

JJB* Posted at 12-29 03:46
Hi padstone,

yes i mean the craft direction (nose to hdg?) on the ground, so the actual heading of the craft as using a manual handheld compass.

Hi jjb the heading was west. 270 degrees, I think however this could be reversed I'm not sure now and could be east. I don't know what stick mode I was using, whatever is factory set I would imagine
Thanks m

padstone Posted at 12-29 03:30
I pulled down and to the left on the left stick as it did this yaw thing, to try and get it back to me as a reflex, then I let go of the sticks but it kept going,. I then pushed up on the stick as I new it was heading for those trees and was trying in vein to clear them, hoping it would come to its senses and come back home if it didn't hit anything. I know I'm going on about this a bit but I want to get it fixed, this ribbon doesn't seem to be a big deal, but is there something wrong with the drone from factory and this will happen again, do I launch a case with dji or is this more hassle than its worth? Others on this forum don't seem to be getting on so well

Regards m

but is there something wrong with the drone from factory and this will  happen again, do I launch a case with dji or is this more hassle than  its worth? Others on this forum don't seem to be getting on so well.
As I mentioned in post #5 the yaw error is induced by your launch point being too close to something steel.
It's not a DJI problem and it's not a fault in the drone, just a fault in your choice of launch point.

There was a left stick movement to the lower right at 1:33 which would cause the MM to yaw right (NNW heading), but there appears to be no input on the right stick to have it fly forward at seemingly full speed.  That being said, it also appears he didn't try to stop it by pulling back on the right stick.

padstone Posted at 12-29 03:51
Hi jjb the heading was west. 270 degrees, I think however this could be reversed I'm not sure now and could be east. I don't know what stick mode I was using, whatever is factory set I would imagine
Thanks m

I had 4 mins flight time total over 3 flights, I was still very much working things out with controls and screen layout. But not doing anything mad. I'm an excavator operator so I know not to go mad with sticks. Is there any veracity to my thoughts that the gimbal cable was damaged prior to flight as I had the gimbal motor warning thing before the crash

M

Labroides Posted at 12-29 03:54
but is there something wrong with the drone from factory and this will  happen again, do I launch a case with dji or is this more hassle than  its worth? Others on this forum don't seem to be getting on so well.
As I mentioned in post #5 the yaw error is induced by your launch point being too close to something steel.
It's not a DJI problem and it's not a fault in the drone, just a fault in your choice of launch point.

I promise I wasn't near any steel structure at launch just a bit of concrete that has no reinforcing in it

padstone Posted at 12-29 03:51
Hi jjb the heading was west. 270 degrees, I think however this could be reversed I'm not sure now and could be east. I don't know what stick mode I was using, whatever is factory set I would imagine
Thanks m

oke  heading in the log shows 218., wich i doubted seeing google maps.

So what went wrong for you

Take off in fly away in OPTI mode, no satellites and no reception.
Fly away from the spot and after 1m4s HP set. (bad luck if you needed a RTH beacuse of lost connection)Beacuse of a wrong compass your MM staryted to drify away, the corrections made to maintain a stabilized hover the wrong direction.

The moment GPS signals are there another possible error can occur, see the chart for the distance to home [ column HD ], it jumps from 0.5 to 1.7 meter in 1/10 second.
GPS position errors are likely to happen.

Always perform a pre and after takeoff checks!

cheers
JJB

Minnesota Posted at 12-29 03:57
There was a left stick movement to the lower right at 1:33 which would cause the MM to yaw right (NNW heading), but there appears to be no input on the right stick to have it fly forward at seemingly full speed.  That being said, it also appears he didn't try to stop it by pulling back on the right stick.

I didn't activate that maneuver that was me trying to catch it

padstone Posted at 12-29 04:00
I had 4 mins flight time total over 3 flights, I was still very much working things out with controls and screen layout. But not doing anything mad. I'm an excavator operator so I know not to go mad with sticks. Is there any veracity to my thoughts that the gimbal cable was damaged prior to flight as I had the gimbal motor warning thing before the crash

M

Is there any veracity to my thoughts that the gimbal cable was damaged prior to flight as I had the gimbal motor warning thing before the crash
No ... the gimbal cable should be perfect for hundreds of hours of flying but as the gimbal is a delicate mechanism, it's often damaged in a crash.
Unfortunately error messages from the Mini don't always show up in the recorded flight data so we can't see the message or when it appears.
The crash impact happened at 1:38.3 and the motion and speed appear significant enough to cause that damage.
It's most likely that the error message appeared as a result of the crash.

JJB* Posted at 12-29 04:05
oke  heading in the log shows 218., wich i doubted seeing google maps.

So what went wrong for you

So what would have happened had he taken off once he had enough satellites but his compass was not calibrated at the take-off point?  Would the same thing happen?  If not, why not?   

padstone Posted at 12-29 04:04
I promise I wasn't near any steel structure at launch just a bit of concrete that has no reinforcing in it

It doesn't have to be a structure.
It could be something as small as a bolt or nail if it's close enough to the compass.
What was under the concrete?
If it did have any reinforcing in it, that is a strong suspect.

There's nothing else that causes a drone to acellerate without stick input as shown in your flight data.

Labroides Posted at 12-29 04:11
Is there any veracity to my thoughts that the gimbal cable was damaged prior to flight as I had the gimbal motor warning thing before the crash
No ... the gimbal cable should be perfect for hundreds of hours of flying but as the gimbal is a delicate mechanism, it's often damaged in a crash.
Unfortunately error messages from the Mini don't always show up in the recorded flight data so we can't see the message or when it appears.

It shows it on the  flight data on the dji app prior to the crash, anyway I can upload that

For people hand-launching and hand-catching, an Apple Watch is magnetic.

Minnesota Posted at 12-29 03:17
Here's the replay (slowed down at the critical part).  Seems to support the OP's claim of a Fly Away.  At first I thought he may have been on Mode 1 but both the speed and altitude ramped with only input on one stick (if we can trust the stick graphics).  Comments?

https://youtu.be/GSPScQfMhHY

Seems to support the OP's claim of a Fly Away
Sorry  but all it's showing is exactly what I described in detail in posts #5, #10 and #14.
That's exactly what happens in a yaw error incident.

Labroides Posted at 12-29 04:19
It doesn't have to be a structure.
It could be something as small as a bolt or nail if it's close enough to the compass.
What was under the concrete?

Are you supposed to know whays under the ground when you take off from a field? There could be an old plough part just under the grass? I'm lost here, do I just fix this myself and avoid the likes of jjb on here in the future as he is obviously an expert before his first flight and does not make mistakes that he seems to find I obviously did

Labroides Posted at 12-29 04:27
Seems to support the OP's claim of a Fly Away
Sorry  but all it's showing is exactly what I described in detail in posts #5, #10 and #14.
That's exactly what happens in a yaw error incident.

Shouldn't there be a Yaw Error indication somewhere in the log?  He never saw or mentioned ever receiving such an error message.  What should a pilot's reaction be in such an uncommanded fly-off?