Hi!

I need your help urgently!

During flight two hours ago the "critical low battery" was reached too early (time was running faster than usual) so that the DJI Mavic Pro landed by itself.

Then I immediately had a "lost signal" and when I showed up exactly at that place where the last signal was recorded, there was no drone :-(

My questions:

1) Is there any way to locate the drone if somebody stole it and then uses it?

2) Can it be that the drone continued it way towards the RTH point so that the last recorded point is not the correct spot where I should now search it?

Please see two attached files.

Regards, Jan

There's a TXT file on your mobile device that contains important information about the flight. You'll need to identify the correct one, upload it to PhantomHelp, and then post a link here and we may be able to help you. The instructions for accessing and uploading the flight log TXT file is found here.

1) Is there any way to locate the drone if somebody stole it and then uses it?

You might be able to get that information from DJI but from what I've seen they don't routinely provide it.

2) Can it be that the drone continued it way towards the RTH point so that the last recorded point is not the correct spot where I should now search it?

Your second screen shot shows that the Mavic was in the process of landing due to a critically low battery, so it's unlike that it proceded towards the home point after that.

Hey Jan - another thing to try is this,
Go to the function FIND MY DRONE - to find it open the app and on the first screen with a picture of a spark black on white BEFORE ENTERING DEVICE - on that first screen top right are 3 horizontal bars.
Tap on this menu and then go to FIND MY DRONE
This will show another map - check where the drone is recorded to be on this map - also check the overlays in that map - hope you will find it there.

This happened to me recently - my flight records showed one place location - It was not there
I then accessed FIND MY DRONE and went to that spot and my drone was there.

When you open FIND MY DRONE there is a red arrow for the drone - if you click on this the GPS co ords will show - hope u find it.

hi everybody,

thanks for your quick replies!

Actually I discovered the "Find my Drone" Feature just minutes after my initial post. The location of the drone shown by "Find my Drone" is exactly the same like in the logs of the "Flight record".
I have searched that specific area for nearly two hours directly after the incident, but the drone was nowhere to be found :-(

When I was taking off the DJI Go 4 App showed that I've got 8 minutes flight time left. So I was like, OK let's do a very quick video and then quickly return home. I did not fly further than 260 metres away and not higher than approx. 110metres.  But then already after 2:46 the mavic entered RTH. That really worried me.

But the real problem was that at only 110 metres distance from me (having 15 GPS satelites!) during "RTH / Landing" the Mavic suddenly lost the connection and the screen of my iPhone connected to the RC did not show any life image anymore (only black and "Connection lost")!

Then I panicked a bit. I never had this situation before so I ran over uneven terrain (stumbled and ripped my shorts...) towards the place where I expected the Mavic to land. As I crossed the street I was nearly hit by a car and then for some moments I lost sight of the Mavic.  As I arrived where I expected the Mavic to be - there was no Mavic :-(

I've got the Mavic for approx. 3 month now and it never lost it signal before.

To me this seems like  a technical fault because it looses signal at 110 metres distance in a height of 113 metres and then it is nowhere to be found, because it just flew away or crashed!

Here are the logs that you requested:
http://www.phantomhelp.com/logviewer/9KD96DLU4V6Z435LQSUD/
I have to admit that at 3:15 I manually steered the Mavic in the wrong direction for 15 seconds.
But as pointed out before, that is not the main problem.

What do you think? Is there any chance that the DJI customer support also sees this as technical fault and that I can get a replacement?

Regards, Jan

fansa2f0a79b Posted at 2017-7-27 11:39
hi everybody,

thanks for your quick replies!

Very sorry about your situation.

I very much doubt that DJI will look at this as a technical/mechanical fault.  
You took off with only 34% battery and when you got the RTH warning at 18%, you continued to fly away in the opposite direction of your home point an additional 250 feet, ignoring the RTH warning.
When you did start back you were over 850 feet from your home point with >17% of battery life left with a 13% critical battery level setting.   If you were fighting a head wind that would have been a long way to fly with only 4% battery.....even no wind at all.

I'm really sorry you lost your Mavic, but I think unless you or someone else found it, you have to chalk this up to experience.

Good Luck!

Thanks for your reply!

What about the fact that the signal got lost while the Mavic was only 110 metres distance away?

I mean: Even with  those 13% critical battery the Mavic should according to its RTH/Landing mode simply have descended those remaining 113 metres (372 feet) and landed - right or wrong?
Instead after the lost signal the Mavic simply vanished / flew away.. :-( This seems very strange to me.

Regards, Jan

jimbolaya Posted at 2017-7-27 13:46
Thanks for your reply!

What about the fact that the signal got lost while the Mavic was only 110 metres distance away?

The last reported position of your Mavic was 35.88845698, 14.40811301 and in a location like that I'd be surprised if someone else found the drone before you reached it. I did notice that it was drifting to the north as it was descending, so start from those coordinates and work your way north and you may still manage to find it.

I don't think there's much chance that DJI will see this as a warranty issue. As Tmgun pointed out, you took a bit of a risk starting the flight with only 34% battery and as far as the disconnection goes it's likely it was caused by obstructions that came between you and the Mavic as it descended. In fact, it appears that it landed on the opposite side of a hill from where you were, so that could certainly account for the lost connection.

Anyway, good luck with your search and please let us know how it turns out.

Maybe someone was watching it when it was descending and grabbed it.

Eagle_Eye Posted at 2017-7-27 15:36
Maybe someone was watching it when it was descending and grabbed it.

I doubt it. Given the height at which it was flying it wouldn't have been easily noticed from the ground, and from the looks of it there probably wasn't anyone near where it landed. More than likely it's still sitting out there somewhere waiting to be found.

Hi Jan, very sorry to hear about your Mavic.

Given your battery power reserves went critical, this may not help but it's food for thought. The fact your phone lost connection with the Mavic doesn't mean that your controller did too. Unless the signal was blocked by obstacles in line with the controller like buildings, trees or natural contours of the terrain, the controller should always maintain signal despite the DJI go app crashing.

Could it be that return to home settings included RTH for controller signal loss as well as critical battery level. I don't know which would over ride the other, but say the Mavic was making a forced landing due to the low battery setting, then lost the signal to the controller, could the lost signal RTH setting have kicked in on what little reserves of power were left in the battery? If this were the case and say the battery was down to 6% reserves, the Mavic would ascend to its pre-set RTH altitude and start heading home only to run out of power at say 50m high and at a speed of say 30kph, then it would fall from the sky at a trajectory you could estimate from those figures. When the battery eventually shut down your flight data would end too, then the last recorded position would not be where to look. It would be somewhere on a line between the last recorded position and the RTH location setting, and then take any wind drift into consideration.

Come on Jan go get your bird and Give  then us a update
.
..........C
.
.

Sorry to hear about this, Jan. I checked the second screenshot and it said the drone landing due to the critical low power, thus it might not be regarded as malfunction, but I would still recommend that you contact our support to start a ticket, we will help to make data analysis for your case, if it's malfunction, we will compensate your drone if it is under warranty according to After-Sales Policy.
Here’s the link to contact us: http://www.dji.com/support

Thanks for your replies!

No, there was nobody in sight who could have picked up the drone or saw it landing.
There was a road in between my starting position and where the last recorded position was.
I had to cross that road (and nearly ran into a car), but there was no car parking on the side of the road and no people anywhere.
Hence I can completely rule out that somebody found it while the incident occured. (Maybe by now somebody who read this post might have found it.)

My setting for "Remote Controller Signal Lost" was "Return-to-Home" However before I have set this setting I have asked the DJI support about what happens at critical low battery and I received this reply: "For the critically low battery, the drone will descend from the current height." Now let's apply this to my situation:

From 03:30 to 04:05 flight time it is in "GoHome" because of the "Low battery warning" (17%).
At 04:06 it switches to "Landing" because it reached the "critical low battery" of 13%. That's fine.
At 04:08 the signal is lost at approx 113m height. At this point the "signal lost" setting seems to falsely override the "critical low battery" setting because at the last known position (04:08 while landing) the drone was not to be found.

I have searched the complete area between the last known position and the starting position.
I have to admit that this area was full of small bushes, vine trees, plants etc. but even after two hours of search I did not find anything.
However I have received different answers from calling the DJI support several times concerning my question: Would the drone continue landing when "critical low battery" AND "signal is lost" or would it try to return home? DJI's different answers indicate that it is not clear under which circumstances the "signal lost" overrides the "critical low battery".

From my point of view the "signal lost" setting should never override the "critical low battery".
You normally set "signal lost => Return-Home" because you want to get your dron back when you flew too far.
But if at the same time the "critical low battery" occurs, then it's clear that returning home is not possible and the drone should land immediately and not try to return home (what my drone most probably did).

How do you interprete the situation where "signal lost" and "critical low battery" both occur at the same time?

Yes, I have already contacted the DJI support and will provide them with all required information.

Regards, Jan

jimbolaya Posted at 2017-7-31 23:23
Thanks for your replies!

No, there was nobody in sight who could have picked up the drone or saw it landing.

Would the drone continue landing when "critical low battery" AND "signal is lost" or would it try to return home?

Yes, during a critical battery descent it continues landing even if the connection is lost. At least that's how it works on the .0400 firmware, so unless DJI changed the behavior in a later firmware release -- which I doubt -- it would have continued landing in your case.

DroneFlying Posted at 2017-8-1 02:17
Would the drone continue landing when "critical low battery" AND "signal is lost" or would it try to return home?

Yes, during a critical battery descent it continues landing even if the connection is lost. At least that's how it works on the .0400 firmware, so unless DJI changed the behavior in a later firmware release -- which I doubt -- it would have continued landing in your case.

Well, my Mavic definitely NOT landed at the GPS coordinate where it switched from "GoHome" to "Landing". I stood exactly at those GPS coordinates (between two small bushes) and searched a radius of approximately 50 metres around it.

Some of you have mentioned that the drone might have continued to the starting point. Can you comment on that how that could have happened even during "critical low battery"?

Another case where the loc8tor would have saved the day.  I can do nothing more than keep repeating, get a loc8tor!!! (Sorry Jan, too late for you)

Tombolian Posted at 2017-8-1 12:04
Another case where the loc8tor would have saved the day.  I can do nothing more than keep repeating, get a loc8tor!!! (Sorry Jan, too late for you)

I fly race quads as well as DJI, always have a locator on the quad when flying, building race quads I install a buzzer/beeper soldered directly onto the FC board and set up as a switch on the Tranais X9D Controller to activate. Absolutely invaluable especially for flying FPV race quads.

There are tracking devices out there the only problem is that they need to have a clear shot to the GPS satellites, so if your quad lands upside down forget it, pretty much that's why every instruction for flying any quad says " always keep visual line of sight while flying" I know it's redundant but if you value your quad they are words to fly by.

QuadKid Posted at 2017-8-1 12:59
I fly race quads as well as DJI, always have a locator on the quad when flying, building race quads I install a buzzer/beeper soldered directly onto the FC board and set up as a switch on the Tranais X9D Controller to activate. Absolutely invaluable especially for flying FPV race quads.

There are tracking devices out there the only problem is that they need to have a clear shot to the GPS satellites, so if your quad lands upside down forget it, pretty much that's why every instruction for flying any quad says " always keep visual line of sight while flying" I know it's redundant but if you value your quad they are words to fly by.

There are tracking devices out there the only problem is that they need to have a clear shot to the GPS satellites

I suspect Tombolian was referring to products like Trackimo and Marco Polo which use cell phone and radios signals, respectively, and neither of them relies on GPS.

DroneFlying Posted at 2017-8-1 15:28
There are tracking devices out there the only problem is that they need to have a clear shot to the GPS satellites

I suspect Tombolian was referring to products like Trackimo and Marco Polo which use cell phone and radios signals, respectively, and neither of them relies on GPS.

"I suspect Tombolian was referring to products like Trackimo and Marco Polo which use cell phone"

he actually mentioned a Loc8tor , which is nothing more than a strobe light, an audio beeper and a handset with a range of 400" for $90 USD

Loc8tor

I have a Trakimo & Trakstar locator, need SIM card ( which they charge you for like a Go Phone ) to work everywhere there is a cell signal. Probably worth it if you are flying distances where you have no idea where you are if you lose VTX or TX signal.
Which may have been helpful to fansa2f0a79b in his case.

QuadKid Posted at 2017-8-1 15:58
"I suspect Tombolian was referring to products like Trackimo and Marco Polo which use cell phone"

he actually mentioned a Loc8tor , which is nothing more than a strobe light, an audio beeper and a handset with a range of 400" for $90 USD

he actually mentioned a Loc8tor

Ah, sorry, you're right; I misread that somehow.

I put a Bluetooth Tile tracker on mine and it completely saved me in New York City. I found my Mavic on someone's rooftop patio.

lvl.1
Flight distance : 276532 ft

Slovakia
Online

  31#
Please help me out with this situation. Yesterday in perfect whether condition, only 194 m away from me, 112 m high, at 59% level of battery (I have 3 batterys to avoid low battery power), with RTH settings on (worked perfectly couple of times) I suddenly lost connection with the drone getting a few notifications on the controller and in 10 seconds it was gone from the screen. The video it made is some how corrupt, I can’t open it with anything. It’s very much looks like a battery failure. I can’t find it so I’m hartbroke because I was saving up for it over a year. I’m a big fan of DJI already had Phanton 2 and Phantom 3 so I’m not a beginner. I really hoping to get an appropriate support from you as I’m even even using for work and has over 2000 followers on Instagram due to my drone work.

https://www.phantomhelp.com/LogViewer/WN4YTGCKRYYOR5XADVL2/

Thank you very much for help

Hi, Sir i have lost my Drone the last thing it said Controller Error then crashed into a water stream now what do i do ? i cant find its body