Ok, so last month while on holiday in Hong Kong I visited the DJI Flagship store and bought a Spark Flymore Combo, Mavic Flymore Combo, DJI goggles and a few other spares.
I decided to get the Spark out to try it out. I updated all firmware which was asked in the Go4 app, charged everything to 100% and brought it on a trip to the Big Buddha in the mountains. While up there I found a nice field to calibrate the compass away from any interference or concrete.  (BTW, while up there there was another Spark owner flying with no remote, just his phone. It executed an auto landing for no reason into the jungle and was lost. I witnessed this with my own eyes). I launched the drone and had a few flights up and around the large monument. Very pleased.

The next day I went out close to the harbour and found a spot to take off from. I took off and flew not too far. After 7 mins of flight, our screen beeped low battery. and immediately after this beep, the drone just dropped out of the sky. While we were searching for our Spark, other drone pilots arrived after us to fly in the same area and didn't have any interference issues.

I was obviously devastated but after reading lots of posts about flyaways and DJI stepping up to honour their warranty was hopeful that I may have some kind of recompense. Either a replacement or even a discount on the replacement. Just in case they didn't, I bought another Spark Flymore, as the prices in Hong Kong are much cheaper than in the UK which is where I live. I figured if they don't step up i can still save money as I love their products.

I discovered there was a big mandatory update from the Spark, which further led me to believe that there was a fault with some drones and probably my one was one of them.

Once back in the UK I had time to contact support to report the issue. DJI support was great in repsonding and helping me pull the relevant files from my phone for analysis. Unfortunately, for the flight in question, my phone does not seem have a log file present. The only evidence I had was the cached video of the flight and crash and a screenshot of the find my drone section in the app. As I feared, they came back to me saying there was nothing they could do for me. I can't help feeling really disappointed as the Spark fell without warning and with adequate power and GPS, and it's not a particularly robust piece of software which can lose logs on flights which end prematurely.

Am I being unreasonable in expecting more? I'm a proven loyal customer who will undoubtedly continue to buy and recommend DJi products and really feel i sould get something back. I'm actually about to push th ebutton on a Crystalsky monitor so every little would help.

I'm also wondering if and tech guys here can let me know where else I can find evidence of this flight other than in the flightrecords directory?

I have put the video of the flight on youtube and if you skip to the end you will see how the drone just dropped for no apparent reason.

Trevor

Case number CAS-938670-K3J0F3

Do you have the logs posted anywhere?

It sounds from the video that low battery warning was given (as you state), and it sounds like a button was pressed (maybe twice) which I assume to be the RTH button.  I also hear the craft go to ATTI mode just before connection is lost.  If you've got the logs some place where we can review, that would be of great help.

Charles Adams Posted at 2017-9-14 09:45
It sounds from the video that low battery warning was given (as you state), and it sounds like a button was pressed (maybe twice) which I assume to be the RTH button.  I also hear the craft go to ATTI mode just before connection is lost.  If you've got the logs some place where we can review, that would be of great help.

Thanks for replying. Yes you're probably right about the rth being pressed. It was quite a stressful moment when it all happened. I did send the whole flightrecords directory to DJI support and the log in question is not there. Is there anywhere else I could find this log?

TrevorL Posted at 2017-9-14 09:50
Thanks for replying. Yes you're probably right about the rth being pressed. It was quite a stressful moment when it all happened. I did send the whole flightrecords directory to DJI support and the log in question is not there. Is there anywhere else I could find this log?

Here's a video that DJI put together on obtaining flight data.  The video contains information about getting some data from the unit itself (which you will be unable to do since it's under water), but it also includes details on obtaining the flight logs from your phone:



Also, I'm not certain that pressing RTH twice is a bad thing.  I'm going to experiment and see what behavior I observe.

There are a variety of places to upload and publicly share your flight data.  I'm hunting down those links.

TrevorL Posted at 2017-9-14 09:50
Thanks for replying. Yes you're probably right about the rth being pressed. It was quite a stressful moment when it all happened. I did send the whole flightrecords directory to DJI support and the log in question is not there. Is there anywhere else I could find this log?

I really like http://www.phantomhelp.com/LogViewer/Upload/ for viewing logs.  You can share the link with us if you are willing (once you have uploaded your flight record).

Sure, I've sent this data to DJi already and extracted it as per the video. Here's a link to everything I had on the phone https://www.dropbox.com/sh/y0p1g ... WYRA_Yb_kbpUEa?dl=0

Couple of points:
1. The crash happened on the evening of the 19th August 2017
2. You will see the video cache of this flight present
3. In the flightlogs directory there seems to be a file relating to that flight
4. In the flightrecords directory the log file doesn't seem to be there.
5. As I was on vacation in Hong Kong from the UK I'm not sure if some times got mixed up in the apps

Thanks for taking the time to look at this. Meanwhile I've been advised to make a claim with my credit card company which I have just done.

TrevorL Posted at 2017-9-14 10:23
Sure, I've sent this data to DJi already and extracted it as per the video. Here's a link to everything I had on the phone https://www.dropbox.com/sh/y0p1guilu50718l/AADEG_cKe4sWYRA_Yb_kbpUEa?dl=0

Couple of points:

I cannot find a flight record in this data for 8/19.  I find some for 8/16, and then a gap and then one for 8/20 and then some for a few days after.  I'm not sure that I'll be able to provide any meaningful analysis without the flight records from the 19th.

Do you own a Mavic in addition to your Spark?

Hi yes CjharlesI own a Mavic also, these are the records you see after the 19th. As i explained in my original post the log for the actual crash flight was not present on my phone.

TrevorL Posted at 2017-9-14 11:25
Hi yes CjharlesI own a Mavic also, these are the records you see after the 19th. As i explained in my original post the log for the actual crash flight was not present on my phone.

DOH!  Sorry, another example of me not "paying attention" to what I'm reading.

Bummer on the logs.

TrevorL Posted at 2017-9-14 09:50
Thanks for replying. Yes you're probably right about the rth being pressed. It was quite a stressful moment when it all happened. I did send the whole flightrecords directory to DJI support and the log in question is not there. Is there anywhere else I could find this log?

You can upload your flight log from your app, use link below to put up your log. Just click on link and follow instructions.

http://www.phantomhelp.com/LogViewer/Upload/

TrevorL, really sorry for your lost. Since you applied for data analysis, our support will help you deal with the problen once you provide the latest flight record and data. Any question, please feel free to talk to us.

That area is no fly zone in Hong Kong

Double checked the case status, our colleagues have contacted you that there is no flight record at that time you described. Could you check and confirm?

TrevorL Posted at 2017-9-14 10:23
Sure, I've sent this data to DJi already and extracted it as per the video. Here's a link to everything I had on the phone https://www.dropbox.com/sh/y0p1guilu50718l/AADEG_cKe4sWYRA_Yb_kbpUEa?dl=0

Couple of points:

In addition, could you please point out which one is the incident record? A screenshot is recommended. You can tell us the date recorded in the flight record, for example, x/8/2017. So we can ensure the exact flight record of the accident. Thanks a lot.  

I'm sure its not the case, but do you have multiple devices (i.e. phones or tablets) that you use for flying with your drone?  In other words, is it possible the log is on a different device?  I'm sure its a ridiculous question, but thought I'd ask to be sure.  Also, maybe you can provide a screenshot from the DJI Go 4 app that shows the video with date stamp on it in the Editor for the Video Album.  Also, in DJI Go 4, if you go to "Me" and then Flight Records, can you provide a screenshot of your flight list that shows the flights around the date of this incident?  Just trying to grasp at as much info as possible in light of the missing logs.

Kloo Gee Posted at 2017-9-15 04:44
I'm sure its not the case, but do you have multiple devices (i.e. phones or tablets) that you use for flying with your drone?  In other words, is it possible the log is on a different device?  I'm sure its a ridiculous question, but thought I'd ask to be sure.  Also, maybe you can provide a screenshot from the DJI Go 4 app that shows the video with date stamp on it in the Editor for the Video Album.  Also, in DJI Go 4, if you go to "Me" and then Flight Records, can you provide a screenshot of your flight list that shows the flights around the date of this incident?  Just trying to grasp at as much info as possible in light of the missing logs.

Hi. Thanks for taking the time out to look at this.

At the time of the crash I was only using one device.

A screenshot of the video album is a super idea, I did not think of that. I've attached a screenshot of the video album. The flight in question is the  07:23 min flight dated the 19/8/2017. (For some reason it has shown the date of the flight as the 19th although the crash was on the 18th)



I've also attached my flight list. Here the crash flight is missing. For some reason the flight time and video time do not correspond.

Thanks again, watch all your youtube videos btw and they are great

This is the crash video file

TrevorL Posted at 2017-9-15 09:50
Hi. Thanks for taking the time out to look at this.

At the time of the crash I was only using one device.

Isn't the "19/08/2017" Hong Kong 275 m 7 min log entry the one we want?  I'd love to see that log right there.

No, the "19/08/2017" Hong Kong 275 m 7 min is a mavic flight.

TrevorL Posted at 2017-9-15 10:07
No, the "19/08/2017" Hong Kong 275 m 7 min  is a mavic flight.

I am baffled.  Kloo Gee (smart guy) may have some ideas that escape me.  I don't understand how a flight can record some video on the local device, but not the flight log.

What if...

I know from video and your message that the drone unexpectedly dropped.  Did something unusual happen specific to the device/app used for the flight?  Like a crash of the app or a system crash/restart?  I have some crazy theories in my head that really don't make any sense (thus I won't embarrass myself yet), but they all start with an unusual event occurring with the device which hosts the dji go 4 app.

TrevorL Posted at 2017-9-15 10:07
No, the "19/08/2017" Hong Kong 275 m 7 min  is a mavic flight.

It's a longshot, but is it possible that you may have either accidentally or purposely chose to "Clear local flight records" in the "Sync your flight records" screen at some point?

Maybe you could try to do another "Sync your flight records", choose "All", and see if maybe it magically re-appears.

Like I said, its a longshot, but can't see that it would hurt to try!

Charles Adams Posted at 2017-9-15 10:14
I am baffled.  Kloo Gee (smart guy) may have some ideas that escape me.  I don't understand how a flight can record some video on the local device, but not the flight log.

What if...

yes it's strange. I'm sure there is more filename based evidence which can confirm the flight existed. It seems that the times and dates are not all correct.

Re the device, I see where you're coming from, I was using an iPhone 7+ on the day and there was no app or phone crash. I remember this because the app just kept saying "Landing now" or something like that. For a while I thought the drone was actually landing.

Another strage thing. Straight after the crash I looked for the video to see where the drone landed (I still believed it had landed at this point) but it was not there. It was only the next day the video showed u in the album

Kloo Gee Posted at 2017-9-15 10:16
It's a longshot, but is it possible that you may have either accidentally or purposely chose to "Clear local flight records" in the "Sync your flight records" screen at some point?

Maybe you could try to do another "Sync your flight records", choose "All", and see if maybe it magically re-appears.

No I'm certain I did not select clear local records. I remember I was worried not to choose that because I may need evidence etc in the future. I've just now done a sync all records again and nothing.

TrevorL Posted at 2017-9-15 10:23
yes it's strange. I'm sure there is more filename based evidence which can confirm the flight existed. It seems that the times and dates are not all correct.

Re the device, I see where you're coming from, I was using an iPhone 7+ on the day and there was no app or phone crash. I remember this because the app just kept saying "Landing now" or something like that. For a while I thought the drone was actually landing.

I just did a test across multiple devices to see if the cached images and video would sync along with the flight records, and they do not.  I know/believe that the flight logs themselves contain thumbnail metadata of images, but not the full cached images and vids.

I'm so not an iPhone aficionado, and don't know how to check for incomplete files.

TrevorL Posted at 2017-9-15 09:50
Hi. Thanks for taking the time out to look at this.

At the time of the crash I was only using one device.

Thanks for your updated. But without your crash flight record ,we can not analyze the accident. Please check carefully and syncing your record again.
Any question, please feel free to talk to us.
Thanks.

Hi,

I did send this via email to support but these are all the files which were on my phone shortly after the crash.

https://www.dropbox.com/sh/y0p1g ... WYRA_Yb_kbpUEa?dl=0

Thanks

TrevorL Posted at 2017-9-15 23:30
Hi,

I did send this via email to support but these are all the files which were on my phone shortly after the crash.

Please note that if the crash data is missing, our support can not analyze the data for you.

Outcome as expected..

Kloo Gee and Charles many thanks.

DJI Elektra Posted at 2017-9-15 23:53
Please note that if the crash data is missing, our support can not analyze the data for you.

May I ask how I can provide the data if the app does not record it?

TrevorL Posted at 2017-9-16 03:31
May I ask how I can provide the data if the app does not record it?

TrevorL, please note that if your app does not record it, we can not analyze it.