I was flying the drone at perfect meteorological conditions and having a good satellite communication, but suddenly at 230 meters the drone lost the connection with the remote controller and informed that RTH mode was activated, but it didn't return to the starting point. I saw the drone going high to return to me, but instead of coming back, it went in the opposite direction, and disappeared.

According to the LOG, the drone is supposed to be in a cliff area, which is inaccessible as the access to this zone is prohibited by the local authorities.

I am very upset since I spent three days looking for the drone by using the binoculars and trying to locate it from various positions, but I didn't find it.

After diagnosis I've this answer from Dji.

We are sorry for the negative experience you've had with our product. The situation is not what we expect and for your case, we also want to figure out the main cause of the flight accident. Because if it’s pilot error, we want to give advice to the customers and also if it’s not, we want to improve our products. However, it was not recorded. The flight record ended at T=02:08 and there is no more available data for us.

Due to the interruption of the record, the cause for this incident was not recorded, but it was verified from the record that there was no malfunction found before the record was cut off. The aircraft was under your control and it worked normally before the flight record ended. It's unable to locate the main reason according to the flight records you provided, we cannot explain the detail of the incident.

Dji wash his hand, don't care about the Mavic mini costumers, dji knows about the lost signal with no warning before the incidence, and without data log after lost signal, the problem is from clients.

This are Dji support?

DATA LOG

https://drive.google.com/folderview?id=1PL2SlfLFzS0Hhr1VtD2gY-_7ucqA_yOd

CARIOCA.LEANDRO Posted at 8-12 05:33
Dji wash his hand, don't care about the Mavic mini costumers, dji knows about the lost signal with no warning before the incidence, and without data log after lost signal, the problem is from clients.

This are Dji support?

If you want an independent opinion, you should post your flight data.
WIthout that no-one can make any helpful comment.

CARIOCA.LEANDRO Posted at 8-12 05:33
Dji wash his hand, don't care about the Mavic mini costumers, dji knows about the lost signal with no warning before the incidence, and without data log after lost signal, the problem is from clients.

This are Dji support?

Sincerely sorry for you, actually several posts on the subject has already been posted more than once on the DJI forum so the problem is well known by the company. I myself yesterday I lost the signal at not even 100 meters I still had it in strong visual fortunately. DJI conclusion will end up losing a lot of customers. Myself who want to spend a range above the mini (mavic air2) I hesitate a lot given their service after sale deplorable and a dubious corporate policy. I really hope they will find a good solution to your problem.
We cannot blame the forum moderators who are mere employees and unfortunately have no decision-making power

Labroides Posted at 8-12 06:05
If you want an independent opinion, you should post your flight data.
WIthout that no-one can make any helpful comment.

https://drive.google.com/folderview?id=1PL2SlfLFzS0Hhr1VtD2gY-_7ucqA_yOd

VanzPix Posted at 8-12 06:07
Sincerely sorry for you, actually several posts on the subject has already been posted more than once on the DJI forum so the problem is well known by the company. I myself yesterday I lost the signal at not even 100 meters I still had it in strong visual fortunately. DJI conclusion will end up losing a lot of customers. Myself who want to spend a range above the mini (mavic air2) I hesitate a lot given their service after sale deplorable and a dubious corporate policy. I really hope they will find a good solution to your problem.
We cannot blame the forum moderators who are mere employees and unfortunately have no decision-making power

Thanks, hope it will be better than a simple discount for a new aircraft!

Labroides Posted at 8-12 06:05
If you want an independent opinion, you should post your flight data.
WIthout that no-one can make any helpful comment.

Updated below with the data log

CARIOCA.LEANDRO Posted at 8-12 06:08
https://drive.google.com/folderview?id=1PL2SlfLFzS0Hhr1VtD2gY-_7ucqA_yOd

Here's what your data looks like:
https://www.phantomhelp.com/logviewer/KDRIG6Z4FPL8FWKU0L8M/

I'm puzzled by your description of the incident as it doesn't match the data.
I can see what happened but cannot match it to your description of the incident.
You said:
suddenly at 230 meters the drone lost the connection with the remote controller and informed that RTH mode was activated, but it didn't return to the starting point. I saw the drone going high to return to me, but instead of coming back, it went in the opposite direction, and disappeared.

According to the data, you flew the drone to a point 250 metres south of where you launched.
You went at full speed in sport mode, let the drone slow and then at 1:45.7, pulled the right stick full down and held it there until the data ended at 2:08.8.
This caused the drone to fly backwards northeast at full speed in sport mode.
At 1:43.4 you also pulled the left stick down to lower the drone about 4 metres.

The drone never entered RTH mode and there's no sign of it rising as you described.
You had full control for the whole flight.
When the data stopped, the drone was 2.8 metres lower than the launch point and would have been extremely close to the ground level there.
But only a short distance in the direction that the drone was flying, the ground rises sharply.

Flying backwards in sport mode, you couldn't see what was ahead of the drone.
The data doesn't show the crash but given the speed of the drone and the terrain and altitude, it's almost certain that it flew into the ground and would be on the ground not much further to the northeast of where it crashed.

I'm surprised that DJI's data people didn't say anything about the terrain or what happened.

Labroides Posted at 8-12 06:44
Here's what your data looks like:
https://www.phantomhelp.com/logviewer/KDRIG6Z4FPL8FWKU0L8M/

Maybe because I'm not in the ground, I'm at 10 meters to the ground, and with -2.9m like you see, I've like 7 meters more to go down if a want. You can't see in the data log, because the drone with full signal with remote control, lost without any loss or warnings... When it passed I saw the drone go up, after lost the signal to come to RTH, but it go for the opposite side... You can pilot the drone only looking to the mobile, but in this case, I have my eyes at the drone, because I need to know where I need to stop, and not crach it. Thanks for your analisis...

Labroides Posted at 8-12 06:44
Here's what your data looks like:
https://www.phantomhelp.com/logviewer/KDRIG6Z4FPL8FWKU0L8M/

Look at the 1:58:01s you can saw the drone with -11.02ft and when lost the signal you've -9.02ft.

And you can't see in the log data the RTH message because it was after lost the signal, and don't have record, if you think it need to be there to explain, dji have a new problem... because if you lost the signal with RTH, and it don't send message to the control....

CARIOCA.LEANDRO Posted at 8-12 07:07
Look at the 1:58:01s you can saw the drone with -11.02ft and when lost the signal you've -9.02ft.

And you can't see in the log data the RTH message because it was after lost the signal, and don't have record, if you think it need to be there to explain, dji have a new problem... because if you lost the signal with RTH, and it don't send message to the control....

Look at the 1:58:01s you can saw the drone with -11.02ft and when lost the signal you've -9.02ft.
I'm not sure what you are suggesting here.
The height that matters is the height of the drone above the ground, not its height relative to the launch point.
The drone was 250 metres away.  How can you tell how high it was above the ground?
The data suggests it was very, very close.


Also .. If you had lost signal, how could the controller tell you that RTH was initiated?

And you can't see in the log data the RTH message because it was after lost the signal, and don't have record, if you think it need to be there to explain, dji have a new problem... because if you lost the signal with RTH, and it don't send message to the control....
If you could find the drone, it's internal data recorder would tell DJI what happened.
But without being able to return the wreckage, DJI have no evidence of what happened or what was the cause of the loss of the drone.
It's tough but without evidence, DJI aren't going to do anything more.

Because I know the waypoint and the altitude from the waypoint and the ground, how could you afirme that is very very close to the ground? How much is it?

Thanks again for your answers!

Labroides Posted at 8-12 07:25
Look at the 1:58:01s you can saw the drone with -11.02ft and when lost the signal you've -9.02ft.
I'm not sure what you are suggesting here.
The height that matters is the height of the drone above the ground, not its height relative to the launch point.

I tell you the app show the RTH mensage, and in the Mavic mini it's like that, I lost signal another time, and its happening when you lost the signal, not before! And in this time, the drone come to me, without any problem!

CARIOCA.LEANDRO Posted at 8-12 07:43
I tell you the app show the RTH mensage, and in the Mavic mini it's like that, I lost signal another time, and its happening when you lost the signal, not before! And in this time, the drone come to me, without any problem!

I tell you the app show the RTH message, and in the Mavic mini it's like that,
The app cannot know that RTH is initiated unless it is still connected to the drone.
There's no way around that.

Labroides Posted at 8-12 08:00
I tell you the app show the RTH message, and in the Mavic mini it's like that,
The app cannot know that RTH is initiated unless it is still connected to the drone.
There's no way around that.

Please answer me, if you have a RTH configured, and your drone lost signal, what it do? The drone automatically start the RTH, and the App give to you that information, because it's programmed!

nevac Posted at 8-12 08:08
[view_image]

nice perspective, I searched all this place with binocular and nothing, if you see the video, you will see the time when it lost the image signals! at the end of the lake!

CARIOCA.LEANDRO Posted at 8-12 08:12
nice perspective, I searched all this place with binocular and nothing, if you see the video, you will see the time when it lost the image signals! at the end of the lake!

It seems to me that the drone hit a rock.

nevac Posted at 8-12 08:17
It seems to me that the drone hit a rock.

nevac Posted at 8-12 08:19
[view_image]

Yes it was the last point recorded, I look there too and nothing, the drone go up and goes to the opposite side from RTH point, don't crash in the rock.

CARIOCA.LEANDRO Posted at 8-12 08:07
Please answer me, if you have a RTH configured, and your drone lost signal, what it do? The drone automatically start the RTH, and the App give to you that information, because it's programmed!

Please answer me, if you have a RTH configured, and your drone lost signal, what it do? The drone automatically start the RTH, and the App give to you that information, because it's programmed!
And answer this .. if you have RTH configured and your drone smashes into rocks at full speed, what happens to your signal and the drone?

And although you believe differently, your app cannot tell you that RTH has been initiated unless you have a signal connection.
Why is that so difficult to understand?
Your app told you that signal was lost but there's no way it could tell you that RTH was initiated.

CARIOCA.LEANDRO Posted at 8-12 08:30
Yes it was the last point recorded, I look there too and nothing, the drone go up and goes to the opposite side from RTH point, don't crash in the rock.

The data shows your drone up to the point where it was inches above the ground with a steep cliff close behind it.
Failsafe RTH automatically activates after the remote controller signal is lost for more than 11 seconds.
At a speed of 12.8 metres/sec, your drone would have continued for something like 100 metres before initiating RTH (if it was still flying).
But it wasn't flying because it had crashed into the cliff.
And that's why it didn't RTH.
It's still up there and if you could get there, you'd find it.

Labroides Posted at 8-12 08:32
Please answer me, if you have a RTH configured, and your drone lost signal, what it do? The drone automatically start the RTH, and the App give to you that information, because it's programmed!
And answer this .. if you have RTH configured and your drone smashes into rocks at full speed, what happens to your signal and the drone?

if you Smash the drone, it don't come back to RTH, but give to you when you lost the signal the RTH message. trust me, I don't give nothing saying this!

Labroides Posted at 8-12 08:38
The data shows your drone up to the point where it was inches above the ground with a steep cliff close behind it.
Failsafe RTH automatically activates after the remote controller signal is lost for more than 11 seconds.
At a speed of 12.8 metres/sec, your drone would have continued for something like 100 metres before initiating RTH (if it was still flying).

I was there 3 consecutive days, searching from the lake, with binoculars and the drone was not there!

Thanks for the information and answers

Labroides excuse his english, What he wants to mean is that after he lost the signal, he phisically saw how the drone rised up (supposed autoRTH) and went to the Oppossite direction after he couldnt see the mini anymore, I know the zone and I consider that the drone rised up because some extreme wind condition which moved it, My opinion? the mini crashed over some rocks close to the zone where he lost the signal, otherwise the RTH would be ok ,the drone itself didnt give RTH on log because signal wasnt never recovered

did you film the flight until the drone lost the signal ?

djiuser_RIeSM3mAo5mf Posted at 8-12 09:04
Labroides excuse his english, What he wants to mean is that after he lost the signal, he phisically saw how the drone rised up (supposed autoRTH) and went to the Oppossite direction after he couldnt see the mini anymore, I know the zone and I consider that the drone rised up because some extreme wind condition which moved it, My opinion? the mini crashed over some rocks close to the zone where he lost the signal, otherwise the RTH would be ok ,the drone itself didnt give RTH on log because signal wasnt never recovered

Thanks, yes my inglish are not a good one!  But you was able to understand perfectly!

Thanks for it!

And thanks for your answer

CARIOCA.LEANDRO Posted at 8-12 08:46
I was there 3 consecutive days, searching from the lake, with binoculars and the drone was not there!

Thanks for the information and answers

Hiya,

Read all the posts and had a look at your flightlog.
If you watched your drone (as you wrote), after the disconnect, and saw the MM climbing than that must be a RTH procedure.
No connection to your device means, as said by others, no RTH logged as the last record logged is when there was a connection.
When disconnect the MM does not fly for 11 seconds in the last RC command, it will stop into a hover. (need some distance ofcourse to stop the speed)

If that is what you saw then your MM climbed to 20 meters, so from minus  2.9 to plus 20.
Is 20 meters above the cliff ? GE shows a height of 53 meters for that cliff above that 'lake'.if it was blown away in that direction it crashed into the cliff.

In the DAT file, on your device FLY030.DAT, wind speed and direction is logged.

If you want to know more upload your DAT in the cloud somewhere and put a link on here.

cheers
JJB

Dirty Bird Posted at 8-12 09:04
I had a Phantom go down in a tree once.  I had a GPS tracker on the drone & knew exactly where it was.  In fact, I knew exactly which tree it was in.  I scanned the tree with binoculars for over 2 hours searching for a glimpse of the drone.  Finally I spotted it, nestled down between the main tree trunk & a couple branches.

That was a Phantom, which is way larger than a Mini, & I only had to search one tree...

Thanks mate, A friend from here told me about next week come to this island, and will make some flying with your drone, and maybe he can see the Mini!

Thanks for your help and answer!

djiuser_RIeSM3mAo5mf Posted at 8-12 09:57
did you film the flight until the drone lost the signal ?

Yes, you can see it at the link on drive... see in the first page

CARIOCA.LEANDRO Posted at 8-12 08:46
I was there 3 consecutive days, searching from the lake, with binoculars and the drone was not there!

Thanks for the information and answers

I have flown this area many times, it’s such a beautiful location, but with the Cliff backdrop and drone 250m away it’s impossible to see a drone the size of a mini. It’s my guess you were disoriented and flying backwards directly at the cliff is where you crashed. This area is not so easy to fly VLOS...An accident that’s all put it down to experience.

The video link gives a 0bytes "doesn't exit" error

Weird...the only way I can see to reconcile both the pilot narrative and the data is not a very probable one: the drone crashed , somehow survived the crash but was damaged in a way that prevented reconnection and made it drift away. . Hmmm.... I've seen my MINI recover from a spin after making contact with a tree at low speed, but running into a cliff is something different.

After losing the connection, the drone would try to "brake", so pitch down while flying backwards, and if it impacted while still braking the props might have survived . I'm not sure how you would otherwise explain the pilot seeing the drone do stuff after losing contact but the drone not reconnecting.

djiuser_RIeSM3mAo5mf Posted at 8-12 11:13
The video link gives a 0bytes "doesn't exit" error

try to update it again

It won't help you, but it must be said here that the footage is breathtaking. What a cool location!!

If I look at that overhanging rocks, I can understand that people are prohibited from entering the area where the suspected crash happened. I wouldn't go there even if I saw the drone lying somewhere :-(

Sorry about the accident. I have seen a credible video of someone lifting a crashed drone to safety from a rooftop with a second drone, but I would not recommend that unless the "search and rescue" pilot is super-experienced.

  
At 25 minutes into the video the pilot discovers that a Mavic Mini cannot lift a Spark(minus the ejected battery...to be expected), but then tries, and succeeds (!) to rescue the Spark with a Mavic 2 Pro.

That's a nice video rescue mate! Thanks for everything! Take care and K.R.

djiuser_RIeSM3mAo5mf Posted at 8-12 09:57
did you film the flight until the drone lost the signal ?

https://drive.google.com/file/d/ ... z/view?usp=drivesdk  this are the video whit the cut signal

djiuser_RIeSM3mAo5mf Posted at 8-12 11:13
The video link gives a 0bytes "doesn't exit" error

https://drive.google.com/file/d/ ... z/view?usp=drivesdk  this are the video whit the cut signal

JJB* Posted at 8-12 10:26
Hiya,

Read all the posts and had a look at your flightlog.

the cliff area. yes have like a 30 meters and 20/25 more in the second step