Few weeks ago I posted about my desperate request of help in recovering my few week old mavic pro but no luck in the end.   
https://forum.dji.com/forum.php? ... mp;page=1#pid989829

Been speaking to DJI support and not much help.    A few question in the meantime:

1:  I POSTIVELY recalled during the last few minutes, after I lost sight of the drone, and BEFORE I lost connection to the drone, I was desperately trying to get the drone to return home BY activing the return home sequence.       However, according to the flight record playback within DJI 4 app,  it did NOT show the return-home sequence being activated.   What could possibly be the problem of RTH sequence not being recorded?

2: During the last recorded moment, I see that the drone decended to height of 4m then it lost connection.     How do we measure height?   Is it relatively to the surface below based on the sensor?     DJI claimed that I've decended the drone into the water.    I, without having sight of the drone, would NOT have tried to land it but it's hard to prove it...

3: I uploaded the data to airdata.com but not sure what to make of it.   Does it offer a flight path playback similar to the DJI 4 app?

4: Does anyone know when I can order the Mavic Pro Platinum WITHOUT the remote?    IF I were to get a replacement, I would prefer the Platinum, but that's a BIG IF as I'm rather disappointed at DJI now...

Please upload the flight log to PhantomHelp (not AirData) using these instructions. AirData is much less useful thank PhantomHelp for diagnosing what happened in cases like this.

Could you please provide me with your ticket or order number? I would like to check the specific details about it.
Besides, if you activated the RTH after the connection lost, the order would not be able to recorded coz it was sent unsuccessfully. So the flight path would not show.
And now we don't have Mavic Pro Platinum (exclude RC, battery and charger) for sale now.
Sorry for your loss again.

DJI Thor Posted at 2017-11-13 21:26
Could you please provide me with your ticket or order number? I would like to check the specific details about it.
Besides, if you activated the RTH after the connection lost, the order would not be able to recorded coz it was sent unsuccessfully. So the flight path would not show.
And now we don't have Mavic Pro Platinum (exclude RC, battery and charger) for sale now.

Tx.  Just PM you the case number.  

DroneFlying Posted at 2017-11-13 06:53
Please upload the flight log to PhantomHelp (not AirData) using these instructions. AirData is much less useful thank PhantomHelp for diagnosing what happened in cases like this.

Thanks.   I'm travelling now so will do so upon my return.   Hopefully that would give me a bit more insights!

How do we measure height?   Is it relatively to the surface below based on the sensor?

Two heights - normally height is indicated as barometric height and is relative to the launch location. I'm guessing it's accuracy is +/- several feet.

VPS height uses pulsed ultrasound to provide a more accurate measurement of height above ground.  It is fairly accurate up to 25 or 30 ft  (depending on atmospheric conditions and ground texture) and is active only when it receives a consistent return echo. It's primary use is to provide a soft landing.

alecela Posted at 2017-11-14 04:26
Tx.  Just PM you the case number.

Hi, just checked your case. The result is the pilot's error. As you can see in the 1st pics below, the drone was toggled Landing when 10:29, then the aircraft entered in landing mode.
The 11:33, the ultrasonic height is 0.1m, the aircraft landed. Please note that the height on the top of the screenshot is the relative altitude to the takeoff point.
Going through the whole record, no RTH was found, the drone just landed in an improper position. So it is not a warranty case.

DJI Thor Posted at 2017-11-14 23:34
Hi, just checked your case. The result is the pilot's error. As you can see in the 1st pics below, the drone was toggled Landing when 10:29, then the aircraft entered in landing mode.
The 11:33, the ultrasonic height is 0.1m, the aircraft landed. Please note that the height on the top of the screenshot is the relative altitude to the takeoff point.
Going through the whole record, no RTH was found, the drone just landed in an improper position. So it is not a warranty case.[view_image][view_image]

Tx.  That's the response I got from DJI as well.   The trouble is honestly I do NOT recall myself landing since at that point I had NO visual of the drone.   It would be silly for me to do so without knowing where the drone was ESPECIALLY given that I'm at the beach front.   Sadly the record is not showing my RTH sequence while I'm pretty sure I was desperate and using RTH was my only way to locate my drone, which ultimate led to my original post.

alecela Posted at 2017-11-16 06:58
Tx.  That's the response I got from DJI as well.   The trouble is honestly I do NOT recall myself landing since at that point I had NO visual of the drone.   It would be silly for me to do so without knowing where the drone was ESPECIALLY given that I'm at the beach front.   Sadly the record is not showing my RTH sequence while I'm pretty sure I was desperate and using RTH was my only way to locate my drone, which ultimate led to my original post.

The trouble is honestly I do NOT recall myself landing

You may not have, at least not intentionally. The first image Thor posted seems to show the landing initiated from a height of 118m and I've seen that happening a lot lately to people who have landing gear extensions attached to the Mavic. The bottom sensor is apparently being triggered, making the Mavic believe it's close to the ground, so if you pull back on the throttle (left stick) it'll start landing as it does when it really is near the ground. In other words, when you commanded it to descend it may have interpreted that as a request to land.

DroneFlying Posted at 2017-11-16 09:40
The trouble is honestly I do NOT recall myself landing

You may not have, at least not intentionally. The first image Thor posted seems to show the landing initiated from a height of 118m and I've seen that happening a lot lately to people who have landing gear extensions attached to the Mavic. The bottom sensor is apparently being triggered, making the Mavic believe it's close to the ground, so if you pull back on the throttle (left stick) it'll start landing as it does when it really is near the ground. In other words, when you commanded it to descend it may have interpreted that as a request to land.

Thanks for the response.   My drone is indeed fitted w/ PGYTech Landing Gear Extension.    To me this is a serious problem as this accessory is actually being sold via the official online store.   If it does cause problem for the sensor, then at the very least, the DJI store should not even carry it...

alecela Posted at 2017-11-18 09:45
Thanks for the response.   My drone is indeed fitted w/ PGYTech Landing Gear Extension.    To me this is a serious problem as this accessory is actually being sold via the official online store.   If it does cause problem for the sensor, then at the very least, the DJI store should not even carry it...

To me this is a serious problem as this accessory is actually being sold via the official online store.

Yes, in fact there was some discussion about that recently.

DroneFlying Posted at 2017-11-18 10:12
To me this is a serious problem as this accessory is actually being sold via the official online store.

Yes, in fact there was some discussion about that recently.

Any idea where/who we can escalate this to?     Have to admit I'm very disappointed by this...

DroneFlying Posted at 2017-11-18 10:12
To me this is a serious problem as this accessory is actually being sold via the official online store.

Yes, in fact there was some discussion about that recently.

I also saw that thread and was baffled that DJI would sell third party accessories direct from their site and then go ahead and state that they don't recommend using it. They're just setting up consumers for confusion. If the landing gears are responsible for OP's malfunction, then DJI clearly should be responsible based on the fact they sell accessories that they don't recommend.

AEM74 Posted at 2017-11-19 14:35
I also saw that thread and was baffled that DJI would sell third party accessories direct from their site and then go ahead and state that they don't recommend using it. They're just setting up consumers for confusion. If the landing gears are responsible for OP's malfunction, then DJI clearly should be responsible based on the fact they sell accessories that they don't recommend.

In fairness, I strongly suspect that DJI -- and PGYTECH before them -- probably did plenty of testing on the landing gear extension before offering it to consumers. Plus, I've seen at least one person using a different kind of extensions have the same problem, so it's not limited to a particular brand / design.

In any case, what used to be a very rare problem is now suddenly fairly common, so I suspect that what's happened is that a hardware or firmware change has somehow made the Mavic more sensitive / responsive to the bottom sensor readings.

I'd be disappointed to see DJI stop selling the PGYTECH stuff because I think they make good products and are filling a niche that DJI hasn't, but I agree that this situation puts DJI in an interesting position.

DroneFlying Posted at 2017-11-19 15:00
In fairness, I strongly suspect that DJI -- and PGYTECH before them -- probably did plenty of testing on the landing gear extension before offering it to consumers. Plus, I've seen at least one person using a different kind of extensions have the same problem, so it's not limited to a particular brand / design.

In any case, what used to be a very rare problem is now suddenly fairly common, so I suspect that what's happened is that a hardware or firmware change has somehow made the Mavic more sensitive / responsive to the bottom sensor readings.

I personally use the PGYTECH landing pad from the DJI store and find it to be more useful than landing gears. Pretty stable even in high winds and doesn't interfere or add weight to the drone while allowing room for the props to spin up safely. I do agree I don't want them to stop selling third party accessories but it sounds like there's miscommunication.

alecela Posted at 2017-11-16 06:58
Tx.  That's the response I got from DJI as well.   The trouble is honestly I do NOT recall myself landing since at that point I had NO visual of the drone.   It would be silly for me to do so without knowing where the drone was ESPECIALLY given that I'm at the beach front.   Sadly the record is not showing my RTH sequence while I'm pretty sure I was desperate and using RTH was my only way to locate my drone, which ultimate led to my original post.

According to the record, it actually initiated Landing at that moment. I conjectured that you initiated Landing instead of RTH since the icon of Landing and RTH are very close to each other. And for the altitude, as I had mentioned above, the height on the record which showed 4 (or 3 at the end) meters, it was the relative altitude to the takeoff position. It was 0.1 according to the ultrasonic result.

DJI Thor Posted at 2017-11-19 23:44
According to the record, it actually initiated Landing at that moment. I conjectured that you initiated Landing instead of RTH since the icon of Landing and RTH are very close to each other. And for the altitude, as I had mentioned above, the height on the record which showed 4 (or 3 at the end) meters, it was the relative altitude to the takeoff position. It was 0.1 according to the ultrasonic result.
[view_image][view_image]

Thanks.   My question now is that IF the landing gear extensions are indeed causing confusion for the VPS, then it's possible that landing was triggered WITHOUT my instruction at 10:29 and at height of 118m which ultimately led to the lost drone?  

alecela Posted at 2017-11-20 03:06
Thanks.   My question now is that IF the landing gear extensions are indeed causing confusion for the VPS, then it's possible that landing was triggered WITHOUT my instruction at 10:29 and at height of 118m which ultimately led to the lost drone?

Can you upload the flight log (TXT file) from your last flight to PhantomHelp and provide a link to it here? It might help your situation if the rest of us can see what DJI already has access to.

DroneFlying Posted at 2017-11-20 04:29
Can you upload the flight log (TXT file) from your last flight to PhantomHelp and provide a link to it here? It might help your situation if the rest of us can see what DJI already has access to.

Ok, here we go:
http://www.phantomhelp.com/LogViewer/9TU25M2O45NS4CMFP1B7/

alecela Posted at 2017-11-20 08:16
Ok, here we go:
http://www.phantomhelp.com/LogViewer/9TU25M2O45NS4CMFP1B7/

I'm afraid that Thor's right about this particular flight. The log doesn't show the sporadic VPS readings that are the classic sign of landing gear extensions being detected by the downward sensor, and there's no negative throttle (left stick) input just prior to the final landing. In fact, the log shows that the landing was initiated through the app, so unfortunately I can't offer any help in getting a warranty replacement for your lost Mavic.

DroneFlying Posted at 2017-11-20 09:43
I'm afraid that Thor's right about this particular flight. The log doesn't show the sporadic VPS readings that are the classic sign of landing gear extensions being detected by the downward sensor, and there's no negative throttle (left stick) input just prior to the final landing. In fact, the log shows that the landing was initiated through the app, so unfortunately I can't offer any help in getting a warranty replacement for your lost Mavic.

Thanks.   So am I right to assume that I'm sh*t out of luck?   

I know the log file might not be telling much but as I said many times before, all I COULD possibly do was to get the drone to return home once I lost sight of it.     How it manifested into a inappropriate landing is beyond me and that's why I came here for help....

alecela Posted at 2017-11-20 03:06
Thanks.   My question now is that IF the landing gear extensions are indeed causing confusion for the VPS, then it's possible that landing was triggered WITHOUT my instruction at 10:29 and at height of 118m which ultimately led to the lost drone?

May I know which landing gear extensions you are using? If they are the unauthorized third-party accessories, then no warranty will be provided. If it is the one that our official store sells, it has been tested and will not affect the use of the drone. Besides, as you can see on the 16#, the relative altitude is 118 meters, and the ultrasonic displays  0, which means the visual sensor didn't work at that time and that height, and it is not the result of the toggle of the landing.

DJI Thor Posted at 2017-11-20 22:27
May I know which landing gear extensions you are using? If they are the unauthorized third-party accessories, then no warranty will be provided. If it is the one that our official store sells, it has been tested and will not affect the use of the drone. Besides, as you can see on the 16#, the relative altitude is 118 meters, and the ultrasonic displays  0, which means the visual sensor didn't work at that time and that height, and it is not the result of the toggle of the landing.

First off, thanks again for the continuous support.    Definitely feeling better support here than the email support I received from DJI so far.  

The landing gear is the PGYTech extension, the very same ones that's sold thru DJI online store.   

As I mentioned a few times, while the flight record doesn't seem to show much in my favour, HONESTLY I was simply trying to set the drone to return home as I have simply lost sight of the drone.   Why & how it started landing while far away from home is beyond me.    Makes no sense that I would try to land when I don't even have the sight of the drone.  

One of the major reasons I bought Mavic Pro as my very first drone is all these fail-safe measures built into the flying experience so I felt reasonably assured that I'll be in good hands while I learn my way along.      But somehow I'm becoming less and less convinced that way...  

alecela Posted at 2017-11-20 22:48
First off, thanks again for the continuous support.    Definitely feeling better support here than the email support I received from DJI so far.  

The landing gear is the PGYTech extension, the very same ones that's sold thru DJI online store.   

Alecela, I so sympathize with your situation, I would also feel very upset if I lost my drone. Since we haven't found any abnormal behaviours of the drone, the drone was initiated landing that time, no RTH was found. Hope you can learn from it and move on.

DJI Thor Posted at 2017-11-21 00:16
Alecela, I so sympathize with your situation, I would also feel very upset if I lost my drone. Since we haven't found any abnormal behaviours of the drone, the drone was initiated landing that time, no RTH was found. Hope you can learn from it and move on.

Tx.  That's actually my biggest problem:  I haven't learned ANYTHING from this painful lesson.     I activated the commands in the event of loosing sight of my drone and nothing returned.     What can I possibly do better next time?   Keeping the drone in my sight ALL the time?     Then what's the purpose of buying a drone w/ 7km range?

Moreover, it's also difficult to move on when DJI only offered 15% discount on the replacement and I see that in many cases, they offered 30% discount!!!

alecela Posted at 2017-11-21 17:38
Tx.  That's actually my biggest problem:  I haven't learned ANYTHING from this painful lesson.     I activated the commands in the event of loosing sight of my drone and nothing returned.     What can I possibly do better next time?   Keeping the drone in my sight ALL the time?     Then what's the purpose of buying a drone w/ 7km range?

Moreover, it's also difficult to move on when DJI only offered 15% discount on the replacement and I see that in many cases, they offered 30% discount!!!

You could also have used the RTH button on RC or as I do just change the to the map view and use that.
I know how it is to lose a drone as it happened to me on my first days of flying.

G_Sig Posted at 2017-11-21 21:52
You could also have used the RTH button on RC or as I do just change the to the map view and use that.
I know how it is to lose a drone as it happened to me on my first days of flying.

Sorry that I left it out in my previous post:   RTH is the EXACT thing I did on the RC upon loosing sight of my drone.   Sadly nothing returned.     So my dilemma are:
1:   I haven't really learned anything from this painful experience so I'm NOT sure HOW I can avoid this in the future, OTHER than keeping my drone is sight which is a bit sad.
2:   The incentive from DJI to return to rather disappointing.  They offered other people who lost their drone 30% discount on replacement but only 15% on mine.

alecela Posted at 2017-11-21 22:13
Sorry that I left it out in my previous post:   RTH is the EXACT thing I did on the RC upon loosing sight of my drone.   Sadly nothing returned.     So my dilemma are:
1:   I haven't really learned anything from this painful experience so I'm NOT sure HOW I can avoid this in the future, OTHER than keeping my drone is sight which is a bit sad.
2:   The incentive from DJI to return to rather disappointing.  They offered other people who lost their drone 30% discount on replacement but only 15% on mine.

You pressed the RTH button on the Remote not on the device screen?

G_Sig Posted at 2017-11-21 22:24
You pressed the RTH button on the Remote not on the device screen?

Believe me I tried BOTH!   That was the first time loosing sight of my drone so I JUST tried all possibility for the drone to return home...

If your Mavic was in Landing mode you would have needed to hit the cancel button the press and hold the RC RTH button for a few seconds for this to be initiated.

Is there no way of getting a local diver to look in this location for you as a water damage repair could be much cheaper than a new Mavic.

Anthony566 Posted at 2017-11-22 18:39
If your Mavic was in Landing mode you would have needed to hit the cancel button the press and hold the RC RTH button for a few seconds for this to be initiated.

Is there no way of getting a local diver to look in this location for you as a water damage repair could be much cheaper than a new Mavic.

It's been over a month now since the incident so I doubt that would make any difference but thanks for the suggestion.   

DJI Thor Posted at 2017-11-19 23:44
According to the record, it actually initiated Landing at that moment. I conjectured that you initiated Landing instead of RTH since the icon of Landing and RTH are very close to each other. And for the altitude, as I had mentioned above, the height on the record which showed 4 (or 3 at the end) meters, it was the relative altitude to the takeoff position. It was 0.1 according to the ultrasonic result.
[view_image][view_image]

Hello Thor,

After speaking to a few fellow owners who had the unfortunate experience of loosing their drone, I started to question the actual software.    You mentioned that the landing was initiated by me.   Is there a possibility that a software glitch caused this?     As I've been 'screaming' at the top of my lung that I NEVER tried to land since I did NOT have line of sight of my drone, HOW it ended up landing is still a big mystery to me.   Worse yet, I have YET to learn any lesson from this painful experience.    if I have to keep a line of sight of my drone at all time, then it defeats the whole purpose of getting a 7km range drone!!!