Hello friends,

I'm hoping someone can help me figure out exactly what caused my crash. I'll break down the exact scenario;

First admition is that I did not calibrate prior to this flight.

I took off and flying was fine, I climed to a high altitude in a remote area no signal issues I remember I was connected to about 13 GPS.

On my descent the aircraft disconnected and I had no stream at this point the controller started beeping and the Mavic continued to descend with out me using the controller.
At this point I wasn't sure if it was doing a RTH and i was using the stick to ensure it landed close to me.
The controller then gave a "STICK ERROR" or "CTRL STICK ERROR" I can't remember exactly and I basically had zero control.
the drone continued to descend and at around 25 feet it just took off in a direct full speed. This was gut wrenching as I had zero control.

Luckily it went in the direct of some thick soft tree's and I was able to retrive it with no damage.

After wards I connected to the drone and could see compass one was showing RED. I can't recall with certainty that I was prompted to calibrate as I took off but I don't think I was.

I'm currently upgrading firmware on both the controller and the drone to todays latest firmware.

My biggest concern up to this point was the disconnections that happened in every flight ( I was thinking it could be the wire connecting the controller to the phone)

I really appreciate anyone that can lend some help as I use the Mavic for work and I've lost confidence in flying. I know I should of calibrated and checked the settings prior i've flown for nearly a year and never ever had any problems I got complacent and luckily no one was hurt and no damaged caused.

Thank you for any feedback and advice.

Without more information all anyone can offer is speculation. Try to retrieve the DAT file for the flight from your Mavic, preferably before upgrading the firmware if it's not too late, upload it to DropBox, and provide a link to it here. If you can then there's a fairly good chance I can provide you an explanation of what happened. The instructions for retrieving the DAT file are here and the correct one should be at least tens of megabytes in size. It should also have a date and time that correspond to when the flight occurred, but if you aren't sure which is the right one then just include any that you think might be the correct one.

If you aren't able to provide the DAT file then the next best thing is the TXT file from your mobile device to PhantomHelp using these instructions and provide a link in this thread to the uploaded log file.

You could upload your flight log files here for others to diagnose.

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

DroneFlying Posted at 2018-1-11 05:29
Without more information all anyone can offer is speculation. Try to retrieve the DAT file for the flight from your Mavic, preferably before upgrading the firmware if it's not too late, upload it to DropBox, and provide a link to it here. If you can then there's a fairly good chance I can provide you an explanation of what happened. The instructions for retrieving the DAT file are here and the correct one should be at least tens of megabytes in size. It should also have a date and time that correspond to when the flight occurred, but if you aren't sure which is the right one then just include any that you think might be the correct one.

If you aren't able to provide the DAT file then the next best thing is the TXT file from your mobile device to PhantomHelp using these instructions and provide a link in this thread to the uploaded log file.

Unfortunately the flight log from that day is not showing on the Mavic in the DJI assistant.
It shows flights before that day and shows todays log from the upgrade.
Same for the txt logs from my phone, it seems like what ever error I had that day didn't log and write to the drone or the phone.

I do have the flight record on the DJI GO app on my phone and can see the flight record and it ends when I got the error.

fans67be01b1 Posted at 2018-1-11 06:21
I do have the flight record on the DJI GO app on my phone and can see the flight record and it ends when I got the error.

That DAT file probably would have provided quite a bit more information about what happened, but if the TXT file is all you have then upload it to PhantomHelp and provide a link to it here.

DroneFlying Posted at 2018-1-11 06:23
That DAT file probably would have provided quite a bit more information about what happened, but if the TXT file is all you have then upload it to PhantomHelp and provide a link to it here.

Oddly there is no txt file on my phone with that date, but within the DJI app there is a record of the flight?

fans67be01b1 Posted at 2018-1-11 06:32
Oddly there is no txt file on my phone with that date, but within the DJI app there is a record of the flight?

I believe the Go app uses the same TXT files to keep a record of your flights, so if the Go app knows about the flight then it's still there. Please double-check the instructions on the PhantomHelp site and you should find the log.

Here's the TXT log guys, thanks very much for taking the time to help me.

http://www.phantomhelp.com/LogViewer/T94GQ2D2OKY6PRXSAHLK/

fans67be01b1 Posted at 2018-1-11 06:45
Here's the TXT log guys, thanks very much for taking the time to help me.

http://www.phantomhelp.com/LogViewer/T94GQ2D2OKY6PRXSAHLK/

Looks to me as if it landed right after you lost your signa for 30ish seconds

Tviscomi Posted at 2018-1-11 06:57
Looks to me as if it landed right after you lost your signa for 30ish seconds

It attempted to land anyway, but when it came down I got some sort of stick error, then as it was descending it randomly just went full speed ahead with no controller input, that's not showing on the log.

Would an uncalibrated compass cause such an error? why the stick error?

Despite what some people say, you should NOT calibrate anything unless the app tells you to.  If it didn't tell you to calibrate, it should have been fine.  But it is good to check the sensor status to make sure everything is in the green too.

Liamonline Posted at 2018-1-11 07:10
It attempted to land anyway, but when it came down I got some sort of stick error, then as it was descending it randomly just went full speed ahead with no controller input, that's not showing on the log.

Would an uncalibrated compass cause such an error? why the stick error?

It attempted to land anyway

RTH was initiated because of the loss of connection, which in turn caused it to start landing. It started descending where it was because it was less than 20m away from the home point and continued more or less straight down, but did continue to respond to your stick input (e.g., elevator at around 3:16).

but when it came down I got some sort of stick error . . . Would an uncalibrated compass cause such an error? why the stick error?

No, I doubt very much that any of this was related to (lack of) compass calibration. I can't explain the stick errors but I don't believe they were related to what happened. The original source of the trouble was the disconnection, which is a problem that people report pretty regularly on this forum. I can't explain the disconnection either, but some people have solved the problem by switching their mobile device to airplane mode, perhaps because it reduces / eliminates interference between the Mavic and its controller.

fans67be01b1 Posted at 2018-1-11 06:45
Here's the TXT log guys, thanks very much for taking the time to help me.

http://www.phantomhelp.com/LogViewer/T94GQ2D2OKY6PRXSAHLK/

you lost signal at 2.11 for approx 35 seconds your Aircraft was at 730ft at 2.11, downlink was restored at 2.47 altitude 580ft approx, so when you lost signal after a certain amount of time your Aircraft went into auto landing mode we can see this at 2.47 your Aircraft has reduced altitude by 150ft,
Stick control error doesn’t show in log but this could have been as a result of Aircraft been in auto landing.
Reason your Aircraft went into landing mode is you were within 20 metres of homepoint when lost signal kicked in so auto land was correct.

Your log ends at 75ft so impossible to say what happened to Aircraft at 25ft.

Why you lost signal, my theory would be you were flying almost overhead directly up overhead when Aircraft is in this position it’s best to have antenna in horizontal position to maintain good signal, just a hunch.

i can only suggest to focus on resolving the disconnect issue.
Some times some of us think it is the app - things to do here are 1. uninstall and reinstall the app - preferably latest update - when deleting the old app ensure cache is cleaned and all dji files deleted because the new app does not always fully uninstall the old one. All else you can do is downgrade to a previous version or wait for the next version to come out hoping that a fix has been made
Some things dji suggests are: replace the cable and ensure it is plugged to the correct inlet of rc - check your environmental conditions - ensure anntenae is pointed correctly

I will second Hallmarks theory/ hunch that yr antenae was not correctly positioned relative to the position of the drone for proper rc connection.

fans67be01b1 Posted at 2018-1-11 06:32
Oddly there is no txt file on my phone with that date, but within the DJI app there is a record of the flight?

Sir, did you get any error message from your app? Could your drone work well after the crash? I would recommend you send it back for repair: http://www.dji.com/support. If your drone is under warranty, please provide the flight data to our support. Thanks for your help.