Hi, while travelling in Costa Rica I lost my Mavic Pro on a flight above the famous Punta Uvita. As I was taking pictures of this place similar to a whale tale in the Pacific ocean, the app disconnected. I tried few times to get it reconnected, but to no avail. Then, as the remote control was still connected with the aircraft, I attempted a RTH, which should have worked because before fliying I waited for RTH location to be properly recorded and also I set the return altitude to 120 m. Unfortunately nothing happeneded. I tried twice, but the RC display showed the aircraft was not coming back. I then tried to return the aircraft manually with the RC. I almost managed to do so, returning the drone back from a distance of nearly 3700 m to 130+ m from me. Unfortunately, the drone must have passed the beach where I was and I didn't see it. When I realized it was again flying further, I turned it, but it was too low in battery, it auto landed, I think in the national park forest, a field, or even a private property. Despite research on the same day, and then the next 2 days, I didn't manage to find it. The SD card contained all pics and videos made with the aircraft during our one month honey moon in Costa Rica!...

I have the video returned recorded on my tablet and I'm already attaching the flight log, in case someone could give a hint where to search still for it....

Thanks already for anyone who will help. Drone might be in bad shape, but most important is to find back the SD card...

Flight log DAT + TXT

Hello and good day Griffon69. I am sorry to know what happened to your previous flight with your DJI Mavic Pro. This is not the experience we want you to have with DJI. We highly recommend syncing your flight records using the DJI GO 4 app and contact our support for our team to provide an appropriate solution and initiate the investigation. The resolution would depend on the warranty of the product and the outcome of the investigation. Just a reminder that if the warranty of the said drone has already expired then DJI will not be able to perform a data analysis for the said drone. You may refer to the link below to contact our DJI Support Team. Thank you.

https://www.dji.com/support

Sorry to know that mate

WeTransfer hyperlink to the flight log DAT https://we.tl/t-pLBvFMiUHm

DJI Stephen Posted at 3-30 09:28
Hello and good day Griffon69. I am sorry to know what happened to your previous flight with your DJI Mavic Pro. This is not the experience we want you to have with DJI. We highly recommend syncing your flight records using the DJI GO 4 app and contact our support for our team to provide an appropriate solution and initiate the investigation. The resolution would depend on the warranty of the product and the outcome of the investigation. Just a reminder that if the warranty of the said drone has already expired then DJI will not be able to perform a data analysis for the said drone. You may refer to the link below to contact our DJI Support Team. Thank you.

https://www.dji.com/support

Hello Stephen, thank you. I'll then do so.

Hi Griffon69,

Sorry for your MP loss and the SD card!

Are you sure that the flightlog is the correct one??

It starts with 94% battery level and ends with 62%.
No RTH in there, no indication that it was close home (130+) as you said.

cheers
JJB

Sorry to hear, just a question, were you on the latest go-app version? I had frequent problems with this aswell. Luckily I could get my drone back by switching off the controller and restarting it...

JJB* Posted at 3-31 02:18
Hi Griffon69,

Sorry for your MP loss and the SD card!

Hi JJB*, yes this is the correct flight log, i.e. latest written and found on my tablet in the DJI FlightRecord folder.
Upon uploading that log onto  http://www.phantomhelp.com/LogViewer , I also noticed it ended at 62%, but that's exactly the point when the app disconnected. It the looks like the log was not written any further

Also, when I said I managed to return the MP close to 130+ meters, that was not from home, but to the place I reached then by running on the beach in the direction of the spot where the disconnect took place (i.e. RC indicated the drone was at 130+ m away from me).

GhostWolf010 Posted at 3-31 02:32
Sorry to hear, just a question, were you on the latest go-app version? I had frequent problems with this aswell. Luckily I could get my drone back by switching off the controller and restarting it...

Hi GhostWolf010, no I was not running the latest go-app, since it was released while I was already travelling in Costa Rica, and I didn't want to take any risk with somewhat poor/slow internet connection there...

Griffon69 Posted at 3-31 07:59
Hi JJB*, yes this is the correct flight log, i.e. latest written and found on my tablet in the DJI FlightRecord folder.
Upon uploading that log onto  http://www.phantomhelp.com/LogViewer , I also noticed it ended at 62%, but that's exactly the point when the app disconnected. It the looks like the log was not written any further

oke, now i understand it completely.
Hard to tell where it had landed, all after 62% batt level to critically low landing is not in the file...

cheers
JJB

Flying a drone on your "one month honey moon"?  Think you are lucky to be alive.  

There is a lesson here for others.  Always backup your microSD card and use multiple microSD cards.  If you are on vacation and photos / videos are of real value to you, copy them to USB stick and mail it home separate from backup copy.

Griffon69 Posted at 3-31 00:27
Hello Stephen, thank you. I'll then do so.

You are very much welcome Griffon69. If you have any other concerns or inquiries with DJI. Please feel free to post it here at DJI Forum. We are all here to help and support you.

HedgeTrimmer Posted at 3-31 09:08
Flying a drone on your "one month honey moon"?  Think you are lucky to be alive.

Hi HedgeTrimmer, both my wife and I love taking pictures and making videos. She is using her camera for ground and I was using my drone for aerial, on mutual agreement ;-)

HedgeTrimmer Posted at 3-31 09:17
There is a lesson here for others.  Always backup your microSD card and use multiple microSD cards.  If you are on vacation and photos / videos are of real value to you, copy them to USB stick and mail it home separate from backup copy.

Hi again HedgeTrimmer, you are right. I didn't bring my laptop, so could not easily backup my microSD. Also I didn't want to invest in a wireless HD that I could have brought with me on this trip.
Unfortunately for me, although I took the precaution to bring multiple SD cards, I didn't think of switching between them! When bad luck is on...

DJI Stephen Posted at 3-31 09:26
You are very much welcome Griffon69. If you have any other concerns or inquiries with DJI. Please feel free to post it here at DJI Forum. We are all here to help and support you.

Thanks again DJI Stephen. I then submitted request (2051012).

Erm 2.29 miles and you could see it ? sorry you lost it ,but always Fly  in line of sight ....Why didnt RTH initiate ? i would of turned off controler...loose signal RTH..

Hi Griffon, I have seen similar before, when you hit RTH you must hold down button for 3 seconds until you here RC continually beeping, if you don’t hold for long enough it won’t register RTH.

How long did you wait at homepoint , it should have smart returned home at low battery, the main part of your log is missing, but you should be able to retrieve from your device.

You should also be able to retrieve low res photos from your device so all may not be lost.


RTH procedure:
Press and hold for 3 seconds
Continuous beeping should occur
Red X will show on telemetry if you need to cancel .

Gazmg Posted at 3-31 10:09
Erm 2.29 miles and you could see it ? sorry you lost it ,but always Fly  in line of sight ....Why didnt RTH initiate ? i would of turned off controler...loose signal RTH..

Gazmg, I don't use a drone to fly in my garden, that's the point.

hallmark007 Posted at 3-31 10:32
Hi Griffon, I have seen similar before, when you hit RTH you must hold down button for 3 seconds until you here RC continually beeping, if you don’t hold for long enough it won’t register RTH.

How long did you wait at homepoint , it should have smart returned home at low battery, the main part of your log is missing, but you should be able to retrieve from your device.

Hi hallmark007, yes I hold the RTH button for long, but without any reaction.
Also, I waited long at homepoint, as I was doing other checks and settings. For example, I clearly heard the message saying that home point had been updated when the drone took off and I kept it hovering few seconds.

Griffon69 Posted at 3-31 12:45
Hi hallmark007, yes I hold the RTH button for long, but without any reaction.
Also, I waited long at homepoint, as I was doing other checks and settings. For example, I clearly heard the message saying that home point had been updated when the drone took off and I kept it hovering few seconds.

Ok just trying to eliminate the usual problems.
Good luck .

Four messages starting at         1m 49.0s ending at 1m 49.3s about:  "GPS Position NoMatch"
Messages  that nobody has been able to tie back to specific cause.  
Although some  who have seen those messages have reported having trouble getting their  drone back to home point.

There was a warning at 9m 26.1s about need for Pilot (OP) command drone to RTH due to battery power.

"Warning__The remaining battery is only enough for RTH. Return home now."
94% - 65% = 29% used to get to current position from RTH
65% - 29% = 36% approximately upon arriving at RTH point  
More than enough for drone to RTH after losing communication.

Near end of flight log, drone bumped up against Maximum Altitude Limit.

Pilot (OP) says he got confirmation of Home point being recorded, confirmed by FlightLog.
Drone and RC / SmartDevice (GO-4 App) quit communicating.
From local flight log, no indication RTH was done, despite Pilot (OP) having done RTH.
Analysis of local flight ends with battery at 62% and drone well away from Pilot.
Flight log ended at time Pilot (OP) reported disconnect.

Perhaps drone didn't actually loose communcation, only appeared too?   
Sounds like SmartDevice (GO-4 App) went awry.

I have experienced a loss of communcation, whereby it took power-cycling both R.C. and SmartDevice running GO-4 to regain control of drone.  Power-cycling only SmartDevice did not get it communicating again.
In that case, power-cycling of R.C. resulted in drone automatically triggering RTH.

Griffon69 Posted at 3-31 09:54
Thanks again DJI Stephen. I then submitted request (2051012).

You are very much welcome Griffon69. If you have any other inquiries or concern with DJI. Please feel free to post it here at DJI Forum. We are all here to help and support you. Thank you.

Griffon69 Posted at 3-31 12:41
Gazmg, I don't use a drone to fly in my garden, that's the point.

Nor do i but i do try and see it even if i know via camera exactly where it is...But never 2 miles away...Good luck with finding her..

Hello, quick update, as I received the below answer from DJI support.

Maggie.Xu (DJI Support)

Apr 3, 16:35 CST

Dear Franck Verchere,

Thank you for contacting DJI Technical Support.

We are very sorry to hear about the unfortunate experience you have had with your DJI product. We take reports like yours very seriously and want to provide you with the best support possible.

Checking the serial number in our system, the drone is activated in 02/Nov/2017. It is out of warranty.

Flight data analysis would be accepted by DJI data analysis team only when the aircraft is within the warranty period.

We would like to offer you a 10% discount to purchase a new Mavic Pro aircraft excluding the remote controller and charger.

To further process it, we would like to collect the following information:
a) Full Name:
b) Phone number (mobile preferred):
c) Shipping Address:

Thanks for your understanding and cooperation, we look forward to hearing from you soon.

Best Regards
Maggie
DJI Technical Support
Website: http://www.dji.com/support
Youtube: http://s.dji.com/Youtube-DJI

JJB* Posted at 3-31 02:18
Hi Griffon69,

Sorry for your MP loss and the SD card!

Hi JJB,
I believe you are the person who understands the workings of the drone and I wonder, can you clarify for me if I have misunderstood the value of return to home.

When you have full connection between controller and drone, pressing and holding RTH for several seconds, until beeping starts should cause the drone to return home.
HOWEVER
In the case of a disconnect, how can RTH help? If there is no longer communications with the drone, how does the drone detect it?
I seldom use RTH and had forgotten the 'hold button down' bit so I probably have forgotten other things as well. Often users with disconnects hit the button, but does it actually work?

AlansDronePics Posted at 4-3 07:54
Hi JJB,
I believe you are the person who understands the workings of the drone and I wonder, can you clarify for me if I have misunderstood the value of return to home.

Hi Alan,

LatLon position of the HomePoint (and RTH height) is also stored in the drone.
Drone will notice that the connection to the Remote controller become broken.
After 3 seconds Drone will start a RTH procedure ; first turn heading towards home, climb if below RTH height (if not close to home, see manual) and fly to home.

So Drone must receive GPS signals to know where it is flying, with no GPS signals and/or bad reception RTH is not possible.
If the drone is flying in ATTI and looses RC connection after some seconds it will autoland.
Some say after 3 seconds, in one of the last logs on here it was after 15 seconds that autoland was started.
This autoland 100% for the Spark, for other drones i do not know....but guess it is the same as a kind of safety feature on DJI drones.
Unfortunately DJI moderators will not react on my question about this!

cheers
JJB

JJB* Posted at 4-3 10:22
Hi Alan,

LatLon position of the HomePoint (and RTH height) is also stored in the drone.

Thank you for the clear explanation. However, I didn't explain myself very well, sorry. I was referring to pressing the RTH button, in the case of a full disconnect. Often users claim that after they realised the drone had disconnected, they hit the RTH button. If there is no connection, how does the drone receive it. I do understand that the drone should return on its own after such a disconnect.

AlansDronePics Posted at 4-3 10:45
Thank you for the clear explanation. However, I didn't explain myself very well, sorry. I was referring to pressing the RTH button, in the case of a full disconnect. Often users claim that after they realised the drone had disconnected, they hit the RTH button. If there is no connection, how does the drone receive it. I do understand that the drone should return on its own after such a disconnect.

Drone won’t receive it, because it’s disconnected, however it is auto for craft to RTH when signal is lost for a certain period of time, this varies between 3/5 seconds.

With regards to Atti mode, and signal lost yes spark lands but P4Pro doesn’t and I suspect that because Mavic Pro and P4Pro were built in around same time ie within a month that Mavic Pro is most likely to react the same way as P4Pro.

AlansDronePics Posted at 4-3 10:45
Thank you for the clear explanation. However, I didn't explain myself very well, sorry. I was referring to pressing the RTH button, in the case of a full disconnect. Often users claim that after they realised the drone had disconnected, they hit the RTH button. If there is no connection, how does the drone receive it. I do understand that the drone should return on its own after such a disconnect.

as said by Hallmark, with no connection pressing once, or twice, or ....nah RTH command does not reach the drone!