Phantom 4 flew in random directions during landing of RTH

Hello there,
Yesterday I had a problem with my Phantom 4. I flew the Ph 4 to 400m distance then pressed RTH button on the controller. The Phantom returned to the takeoff GPS coordinate without any issue. However, during landing it started to fly in random directions with high speed. I quickly cancelled the RTH and barely landed it manually. Could someone explain me what happened so I could avoid such situations in the future.
The flight record is available in the following link:

https://www.phantomhelp.com/LogViewer/5AZW147I0MTM0TR9LJG0/

Cheers,
Ilkhom

Looks to me like you cancelled the autoland after RTH and were still issuing elevator commands. You never released the stick. Also, a second RTH was issued and you continued to give elevator commands.
That would explain the high speed.

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@Ilkhom_Abdurakhmanov, you can see the position of the remote controller sticks at the bottom, right corner of the map here:

If the drag the green slider below the map through the parts of the log where your Phantom was landing, you’ll see what @Fly_Dawg mentioned above.

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Thank you very much for the detailed response. Now I learnt that my right stick was always in the forward (up) position during the entire flight. What still puzzles me is that in the time frame from 3m22s to 3m26.4s even though the flight mode was ‘Auto Landing’ the aircraft was not in the fixed GPS position but flew in different directions with nonzero and non-constant speed.

Also, I don’t understand several ‘GPS position NoMatch’ warning messages during the flight. I hope they are not serious and not related to this issue?

It actually was only flying forward during that time. And that makes sense since you had the right stick (the elevator) in the up position. Had you not been commanding it forward, it would have descended straight down toward the home point.

@BudWalker, do you have any idea what these messages mean?

So you are basically saying that control sticks are active even during the RTH and should always be in straight position?

What about the ‘GPS position NoMatch’ warning? Is it something I should be worried about?

When using automated flight modes (like RTH and auto landing), you should not touch the remote controller sticks. However, it’s a good idea to be ready to move the sticks if something doesn’t go as expected. Before doing that though, you should press the RTH button or pause button to cancel the automated flight mode so you do not have to battle the aircraft as it tries to follow the automated flight path.