Hello everyone,

I lost my Mavic mini yesterday.   The drone was around 120m up and 160m away from me when the controller lost the connection.
The battery was at 82% and had been in the air for around 4mins.

The drone failed to return to its home point and despite an extensive search of its last recored position, i have been unable to locate it.



I have taken out the care refresh for the drone, but I dont have one to send back.

Are DJI able to help with a replacement?

DJI might help depending on what your logs say, could you upload them for us to help evaluate what might of happend? You can follow these instructions, yes they apply to the mavic mini.


Phantom Help

It would also be interesting why RTH didn't work. RTH height too low and the Mini crashed into a tree ... perhaps ?

here is a copy of my flight log   https://www.phantomhelp.com/logviewer/QTIYNMRKL5COLCBA71Z2

was too windy to fly my mini where im at in the uk yesterday, how was the wind where you were?

Bezik Posted at 5-12 04:32
was crazy windy where im at in the uk yesterday, how was the wind where you were?

The wind was not too bad, I only had a couple of warnings and according to the App UAV forecast is was good to fly.

jonny007 Posted at 5-12 04:29
It would also be interesting why RTH didn't work. RTH height too low and the Mini crashed into a tree ... perhaps ?

It was over 400ft up when it lost connection, my understanding is it would  stay at that height on its return to home if its return altitude is lower.

bablefish Posted at 5-12 04:35
The wind was not too bad, I only had a couple of warnings and according to the App UAV forecast is was good to fly.

if thats the case best thing would be to post the flight data as others have said, if it was the drones fault you might be in with a chance of DJI helping you
edit: oops just noticed you posted the log, sorry

Completely depends on the logs after you submit your ticket. Heard stories that can go either way. Good luck.

bablefish Posted at 5-12 04:32
here is a copy of my flight log   https://www.phantomhelp.com/logviewer/QTIYNMRKL5COLCBA71Z2

Hi bablefish,

Had a look at your flight and i am puzzled.

At the end of your flight, with no RC input your MM was stable hovering at 223 meters away, pitch and roll angles low ; so not to much wind to fight against.

Earlier in flight your RTH performed OKE, speed towards home between 6 and 7 m/s with pitch down angle of approx 27 degrees. At 2m38 distance to HP 197 meters, at 2m55 you cancelled RTH at 103 meters from home. So all looks normal to me.

Why after the disconnect your MM did not fly home??  i have no idea.

Only at the end few times more this warning : " Strong wind warning. Aircraft unable to Return to Home automatically. Lower altitude immediately and Return to Home manually"
So mayby (guess the only logical reason for not returning to home) is more wind at the end at that distance out if 225 meters, but as said before 'hovering with low pitch/roll angels' are telling less wind. So i am puzzled.

cheers
JJB

JJB* Posted at 5-12 05:05
Hi bablefish,

Had a look at your flight and i am puzzled.

Thanks for looking at my log.

I'm at a loss as well as to why is did not return.

There was an occasional gust, but nothing too much and as you mentioned not when I lost contact.

Hi!

I think you flight behind the monument. You startet down the hill and the monument is 67 meters high. In this case 400 feet are not enough. Behind the monument is no w-lan connection.  Perhaps the mini starts a RTH and crashed to the monument.  

   

If the controller lost full contact with the drone, it would not be able to record all events I guess.

werdschowern Posted at 5-12 05:44
Hi!

I think you flight behind the monument. You startet down the hill and the monument is 67 meters high. In this case 400 feet are not enough. Behind the monument is no w-lan connection.  Perhaps the mini starts a RTH and crashed to the monument.

I was just about to write ... "radio shadow", if this is the right word for "Funkschatten".
The last position of the drone is in the direct line to the HP and exactly in between the monument.
Above all, this scenario would apply if the drone was below the top of the monument. And: the current altitude was higher than the set RTH altitude.

At a glance, it looks like 400ft may not have been enough
edit - does the preview video you have show it being above the height of the monument?

werdschowern Posted at 5-12 05:44
Hi!

I think you flight behind the monument. You startet down the hill and the monument is 67 meters high. In this case 400 feet are not enough. Behind the monument is no w-lan connection.  Perhaps the mini starts a RTH and crashed to the monument.

good find!

I saw this in GE, did not know there was a monument there
Next time i will search better  ;-)
cheers
JJB

JJB* Posted at 5-12 06:56
good find!

I saw this in GE, did not know there was a monument there

Drone has now been found at the top of the tower :-)

No idea what state it is in, but I will be able to collect it from reception tomorrow.

The owners are rather upset that I was flying around the monument.  Apparently they do not allow drone flights.  I checked on the NATS app and it does not show it being a no fly zone.

What are the regulations/guidance for flying around things like this.

That's a good result

You're supposed to keep 50m from buildings
There are also privacy regs if filming

Maybe offer to make a small charity donation to their chosen fund as an apology if they hand it back?
As your luck seems in I wonder what the chances are of it being someone else's crashed magic 2 pro? That would be a moral dilemma ;)

This one seems pretty easy.

He tried to get around that massive tower (National Wallace Monument), predictably lost connection, failsafe-RTH activated but was just 193ft, the Mini tried to go home directly at 404ft but failed to do so and with very high probability smashed into the National Monument.

I do not see any Strong Wind Warnings from the way I look at the log, but I am not interested in that. The cause seems pretty clear.

Let's see if some member of the Flying Taliban Drone association will chime in to say a nail screwed up the yaw (which it might be possibile but from personal tests I have concluded that a nail must be directly SHOT inside the Mavic Mini with an air gun to cause a significant alteration)

Anyway... considering what happened I'd be far more concerned about drone recovery rather than a refund from DJI. I strongly suggest the OP to take down the flight log asap and seek to find a friendly contact with the institute managing the national monument.
-----

Wow... I am amazed... I started writing this down before the latest replies where the drone is found.
Glad for the finding... I think now an apology is due if they don't tell the authorities.

bablefish Posted at 5-12 07:03
Drone has now been found at the top of the tower :-)

No idea what state it is in, but I will be able to collect it from reception tomorrow.

If it’s National Trust they don’t allow

bablefish Posted at 5-12 07:03
Drone has now been found at the top of the tower :-)

No idea what state it is in, but I will be able to collect it from reception tomorrow.

If only your RTH height setting was higher....
uhh, monument is 67 meter high, your MM was at an altitude of 123 meters when loosing connection!So it should fly in a direct line over the top of this tower.
Nope, ofcourse not, your takeoff point must be lower than the bottom of the tower.
cheers
JJB

I took freedom to check the .csv log produced with FRAP previously, the GoHome field was set to 1, thus RTH presumably.

m80116 Posted at 5-12 10:13
I took freedom to check the .csv log produced with FRAP previously, the GoHome field was set to 1, thus RTH presumably.

Last recorded record is "standby" for gohome, so YES it was activated (last postion > tower crash)) but NO evidence in the log present.

Do you know what's the field in the FRAP generated .csv for the loss of connection?

I assumed it was HOME.goHomeMode which remained at 1 the entire flight. Isn't it ? Anyway... if it hovered there there's good chance of low damage in the event of a landing in the trees.

bablefish Posted at 5-12 07:03
Drone has now been found at the top of the tower :-)

No idea what state it is in, but I will be able to collect it from reception tomorrow.

I may be wrong, but as far as I know, you did not break any rules. The 'owners' have no control over whether you fly near the monument or not, that is under control of the CAA. As long as you do not land or take off from their land, and you stay 50 Metres away from a actual building, you are OK.

I guess you had the RTH height setting lower than the tower...

Geebax Posted at 5-12 15:02
I may be wrong, but as far as I know, you did not break any rules. The 'owners' have no control over whether you fly near the monument or not, that is under control of the CAA. As long as you do not land or take off from their land, and you stay 50 Metres away from a actual building, you are OK.

There's the privacy one I noted earlier and he hit the building so 50-meter rule as well (is that law or guidance?)

If they are feeling really cross they could report you for lockdown breach so don't mention when you crashed it (it's been up there for weeks honest guv!)

m80116 Posted at 5-12 08:26
This one seems pretty easy.

He tried to get around that massive tower (National Wallace Monument), predictably lost connection, failsafe-RTH activated but was just 193ft, the Mini tried to go home directly at 404ft but failed to do so and with very high probability smashed into the National Monument.

Let's see if some member of the Flying Taliban Drone association will chime in to say a nail screwed up the yaw (which it might be possibile but from personal tests I have concluded that a nail must be directly SHOT inside the Mavic Mini with an air gun to cause a significant alteration)What's the matter with you?Why do you even say this rubbish?

1.  No-one (who knows anything about drones) would suggest that a yaw error had anything to do with this incident as there are none of the characteristic signs of a yaw error incident.
2.  As you frequently demonstrate, you have very little understanding of how drones work.

I love a story that ends.....ok ....sorta well ;-) Share the video, if any, with the monument people and offer to make more videos suited to their taste. It may go well for you both. Point out that the Mini is tiny in weight and can't barely hurt a brick ;-)

itchyeyeballs Posted at 5-12 07:10
That's a good result

You're supposed to keep 50m from buildings

That is extremely funny ;-)

m80116 Posted at 5-12 14:34
Do you know what's the field in the FRAP generated .csv for the loss of connection?

I assumed it was HOME.goHomeMode which remained at 1 the entire flight. Isn't it ? Anyway... if it hovered there there's good chance of low damage in the event of a landing in the trees.

Best to get knowledge about field values is to fly single mission, and check afterwards all fields.
Repeat this over and over again (do something else in flight etc) and check and learn.

For this, fly your drone, switch off controller and see what is happening in the log....

cheers
JJB

JJB* Posted at 5-13 00:00
Best to get knowledge about field values is to fly single mission, and check afterwards all fields.
Repeat this over and over again (do something else in flight etc) and check and learn.

Well just a little update.

The kind people at the monument have returned my Mini.  Alas it did not do too well in its little crash.

The camera gimbal is hanging out, the battery door wont close, it lost 2 propellers and cracked another one and finally there is a chip out of the top of the drone.

Thank goodness for care refresh

bablefish Posted at 5-13 02:12
Well just a little update.

The kind people at the monument have returned my Mini.  Alas it did not do too well in its little crash.

Many happy landings with your replacemen MM!

cheers
JJB

An explicative picture wouldn't be wasted... anyway did you ask the personnel there if they did find it under some trees or if they found as earlier indicated at the top of the tower?

If it was at the top it means the poor thing tried to return most probably, and collided with the tower.

m80116 Posted at 5-13 06:43
An explicative picture wouldn't be wasted... anyway did you ask the personnel there if they did find it under some trees or if they found as earlier indicated at the top of the tower?

If it was at the top it means the poor thing tried to return most probably, and collided with the tower.

It was found on the viewing platform at the top of the tower.

From the state it is in, I would think its collided high up on the tower and bounced about a bit on the way down to the viewing platform.

It's already wrapped up waiting to go to Holland.
Here is the video before I lost connection

I can't see the vid.

m80116 Posted at 5-13 11:27
I can't see the vid.

The video from before the crash
https://drive.google.com/open?id=1rsfdvkdyiGumxIxAaQVerWx2Gv9m9mIo

bablefish Posted at 5-13 12:40
The video from before the crash
https://drive.google.com/open?id=1rsfdvkdyiGumxIxAaQVerWx2Gv9m9mIo

They footage looks epic....it is so pity Mini lost the signal and tried to retirn home

I don't like what I am seeing. Seems like a FAILED quickshot to me.

It probably ended before it could complete... and then it smashed into the tower (for loss of connection, RTH), but if it is what I think it is (quickshot) it seems it was bound to fail, I mean... it was (about) on course for a collision for what I can see. JJB's quickshot tour of the treadmill springs to mind.

Why doesn't the video include the crash? That would seem to be important to this topic.