Flight Log

[Music One]

I was taking some arial photographs yesterday with my Mavic Air of a pier on a seafront. Mainly flying over the sea but not far out. Also took some shots from over a pebble beach. It was foggy and very atmospheric. Whilst over the pebbled beach not very high, the lady in the Go4 app suddenly said Landing. It started to descend and there wasnt much time. I tried to gain height but it wouldnt let me, kept coming down but it did allow me side movement. I was lucky and just in time to move it a few feet on to a slipway and it landled safely. I cant be sure if I accidently activated it or not. I was planning on landing not long after this happened as battery level was getting low. I didnt have enough time and guess I was sorta in a panic I didnt pay attention if a cancelation cross was on the screen nor did I try the pause button. So not sure if they would have fixed it. I looked up some vid on here and found out how to download a flight log, which Ive done. Not that I would understand it but what is best to use to open the log. All my computers here are unable to read it. I have attached it here in the hope that someone might be able to tell me what happened (hoping it was something I did). Thanks in anticipation.

 

[Music One]

Log didnt upload. Try again.

 

[Simmo]

Log didnt upload. Try again.

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

 

[Music One]

Ok for some silly reason I seem to be making a pigs ear of this. I have connected the MA to my computer and opened to Assistant 2 app. I can access the file and have downloaded it into my computer. Its quite a large DAT file. I thought I could just attach that on a thread here with the attach files icon. But it doesnt seem to want to upload. Thanks for that other info Simmo. I guess I need that for my own viewing, but do I need to use that also to be able to attach the file on here. Sorry to be a pain.

 

[Simmo]

In the first instance, just post the TXT file.
The DAT file is indeed large and will need to be uploaded to dropbox or similar, and post a link here.
Follow the instructions in the link I posted, and then again, post the link back here.

 

[Deleted member 94047]

Ok for some silly reason I seem to be making a pigs ear of this. I have connected the MA to my computer and opened to Assistant 2 app. I can access the file and have downloaded it into my computer. Its quite a large DAT file. I thought I could just attach that on a thread here with the attach files icon. But it doesnt seem to want to upload. Thanks for that other info Simmo. I guess I need that for my own viewing, but do I need to use that also to be able to attach the file on here. Sorry to be a pain.

You are looking in the wrong place. The log files in the Aircraft are encrypted and can only be read by DJI, so pretty useless for anyone else. You ought to find and upload the .txt and .DAT files from the phone/tablet you are using with the RC. For instructions on how to access these files see here and here.

 

[Music One]

Thanks for both your help .. oki dokes .. I have found the .txt hopefully here they are ... I did have a short flight after the event and all seemed normal with the MA .. so I think its the 11.31.03 at the end where it happened.

 

[Redleg]

@sar104 @Meta4

 

[Deleted member 94047]

Thanks for both your help .. oki dokes .. I have found the .txt hopefully here they are ... I did have a short flight after the event and all seemed normal with the MA .. so I think its the 11.31.03 at the end where it happened.

Unfortunately, none of those three log files show an autolanding. Most likely, you haven't found the correct log file. Notice the file names, they go like "DJIFlightRecord_2019-10-23_[11-39-58]". The first three numbers are the date in YYYY_MM_DD and the last three in the "[ ]" are the time in H_M_S. Perhaps you can find the correct log file using this as a guide.

I was wrong!

 

[sar104]

Unfortunately, none of those three log files show an autolanding. Most likely, you haven't found the correct log file. Notice the file names, they go like "DJIFlightRecord_2019-10-23_[11-39-58]". The first three numbers are the date in YYYY_MM_DD and the last three in the "[ ]" are the time in H_M_S. Perhaps you can find the correct log file using this as a guide.

Actually it was the first posted log (DJIFlightRecord_2019-10-23_[11-21-02].txt). The problem is a fairly common one when flying in foggy conditions - the VPS system was mistakenly seeing the fog as ground, and so the recorded VPS height was close to zero for much of the flight. As a result, at the end, as soon as full down throttle was applied to start descent, the FC initiated the landing sequence:

 

[Deleted member 94047]

Actually it was the first posted log (DJIFlightRecord_2019-10-23_[11-21-02].txt).

Oops, I did it again!

 

[Redleg]

I was wrong!

Still better than I could have done.

 

[sar104]

Oops, I did it again!

It had some subtlety, and was not immediately apparent without looking at the details.

 

[Music One]

Thankyou thankyou for doing this. It is really much appreciated. At least I now know the cause and lesson to be learnt, do not fly in any mist or fog. I was lucky, as I said that I could have been over the water. If you were all in my neck of the woods I would buy you some beers. Thanks again.

 

[sar104]

Thankyou thankyou for doing this. It is really much appreciated. At least I now know the cause and lesson to be learnt, do not fly in any mist or fog. I was lucky, as I said that I could have been over the water. If you were all in my neck of the woods I would buy you some beers. Thanks again.

If necessary it can be avoided by disabling VPS and landing protection.

 

[Music One]

That crossed my mindtoo yesterday Sar. Still, Im not going to take any further chances. I guess the damp is not very good for it either. It did have lots on moisture on it when it landed. Out of interest, If I had engaged the pause button or entered sports mode would it have halted the landing proceedure? Dont know if it offered me the little box with a cross in to cancel it either.

 

[sar104]

That crossed my mindtoo yesterday Sar. Still, Im not going to take any further chances. I guess the damp is not very good for it either. It did have lots on moisture on it when it landed. Out of interest, If I had engaged the pause button or entered sports mode would it have halted the landing proceedure? Dont know if it offered me the little box with a cross in to cancel it either.

Probably, or you could have cancelled landing by applying throttle.

 

[Music One]

I did apply Throttle but it wasnt taking any effect, just kept coming down.

 

[sar104]

I did apply Throttle but it wasnt taking any effect, just kept coming down.

I'm afraid that you have misremembered what you did. In the graph below, the throttle is the black trace.



After the 9 seconds of full down throttle that caused the descent and landing sequence, you didn't apply any significant throttle of any kind. You did apply full right rudder, which likely also lead to the small positive blip in the throttle at 524 seconds, together with a mixture of elevator and aileron, but no throttle.

 

[Music One]

Oki dokes Sar. Sorry for the misinformation. It all happened quite quickly and my mind was working overtime. At least I know the reason, so thanks once again for your patience and help. Im fascinated with the graphs. Once more out of interest, where it shows the height in metres, I see it shows -5m on landing. It did land about 20ft away from me on a sloping slipway but that wasnt 5m below where it took off I thought. Sorry so many questions but really interested in it all.