Fly Away, lost RC uplink. Don't know why

[RadRocket]

I'm pissed. Drone was right over my head and decided to go into RTH. I didn't activate it, and I didn't lose signal. So naturally I decline the RTH so I can continue filming what I was filming. And left me with no control, I had pgps and everything just no control. And it just drifted away. Then I tried toggling S2 to 're activate RTH and nothing worked not even shutting it off. DJI Flight Log Viewer - PhantomHelp.com

 

[Meta4]

I'm pissed. Drone was right over my head and decided to go into RTH. I didn't activate it, and I didn't lose signal. So naturally I decline the RTH so I can continue filming what I was filming. And Litchi left me with no control, I had pgps and everything just no control. And it just drifted away. Then I tried toggling S2 to 're activate RTH and nothing worked not even shutting it off. I feel using litchi was the only fault here.DJI Flight Log Viewer - PhantomHelp.com

The flight data shows your Phantom entering RTH which you cancelled after 12 sec.
The Phantom is in P-GPS mode for 18 sec and from then on it is in aiti mode.
As there is no error message to indicate any compass error, it would appear that you've switched to atti mode which disables GPS position holding and braking.
That can be disorientating and also allow the Phantom to drift with the breeze.
The data ends with the drone 1600 feet away, 218 feet up and being flown/drifting northeast at 8-10 mph.
Although you used the right stick quite a bit during the drifting, there is very little attempt to turn the Phantom towards home with the left stick and for most of the time it was untouched.
When you did use rudder, the Phantom turned as it should, indicating that you did have control.

To recover, you should have switched from atti to P-GPS mode and used the radar display to fly back or used RTH

 

[Oso]

The flight data shows your Phantom entering RTH which you cancelled after 12 sec.
The Phantom is in P-GPS mode for 18 sec and from then on it is in aiti mode.
As there is no error message to indicate any compass error, it would appear that you've switched to atti mode which disables GPS position holding and braking.
That can be disorientating and also allow the Phantom to drift with the breeze.
The data ends with the drone 1600 feet away, 218 feet up and being flown/drifting northeast at 8-10 mph.
Although you used the right stick quite a bit during the drifting, there is very little attempt to turn the Phantom towards home with the left stick and for most of the time it was untouched.
When you did use rudder, the Phantom turned as it should, indicating that you did have control.

To recover, you should have switched from atti to P-GPS mode and used the radar display to fly back or used RTH

Exactly my assessment, plus yet another example of winds at altitude which we warn about regularly especially when in atti mode.

What I don't yet see is a clear explanation of why it went to RTH mode.

 

[Fly Dawg]

You don't suppose this is a possibility do you? You lost uplink according to the data.

 

[Pharm]

Exactly my assessment, plus yet another example of winds at altitude which we warn about regularly especially when in atti mode.

What I don't yet see is a clear explanation of why it went to RTH mode.

Possibly because it was directly overhead, the location of weakest signal.

 

[Fly Dawg]

You did not notice ( For some reason) that you lost signal to the Phantom, which would explain RTH while you thought you were still connected, because the downlink was still good giving you video and telemetry. Just my assessment.

 

[Oso]

Possibly because it was directly overhead, the location of weakest signal.

That is something we warn against all the time and one of the first things I looked at in the log along with battery levels. In this particular case, he wasn't directly overheard at that time though he was at one point during RTH.

I also did not see a loss of control signal in the high level log, but @Fly Dawg found evidence of that in a deeper analysis.

 

[Fly Dawg]

Notice in this plot. The top graph shows the elevator inputs from the RC and the Pitch response from the aircraft on the bottom graph. Nearly zero after 150 seconds in to the flight, which shows loss of RC uplink.

 

[Fly Dawg]

In summary, It appears that RTH was cancelled at approx: 1:45 seconds ( Just before uplink loss). The aircraft then went in to ATTI mode and drifted with the wind with no possibility of a manual RTH due to loss of uplink from the RC. This is unfortunate but the data does not show a fault of Litchi. Had RTH not been cancelled it would have come back ( The aircraft had already begun the return flight).

 

[RadRocket]

Ok, data shows loss of RC uplink. That's a good explanation. But , I always cancel rth and land manual when it's overhead. In this unfortunate case the uplink was lost moments before that. And I never really went far from takeoff point when this happened.

 

[Fly Dawg]

And I never really went far from takeoff point when this happened.

This is true. You were a couple of hundred feet up or so and basically right overhead. It is odd that the signal would be that weak, so close. The only plausible explanations are that either you did not have your antenna oriented correctly, or you already had a transmitter issue. But I suspect more the former, due to the extreme signal fluctuations during the time frame. Although the other is possible, I grant you.

 

[Jayfdee]

OK, so Litchi exonerated again, they always are the first to be blamed.

 

[BigAl07]

Keep in mind even if Litchi stalls, locks up, crashes etc you still have control of the aircraft so long as you have a solid Tx/Rx connection. While I fully understand you wanting to blame Litchi for this the data paints a much different picture.

Would you mind editing (or allowing a Mod to edit) your thread title to reflect a more accurate situation?

 

[RodPad]

@RadRocket,
Are you going to look for it?
Drifting at 8 miles an hour, with 80% battery, and it wasn't trying to come back, it still would have auto landed?
8 mph for about 15-20 mins, dang that sucks.

@BigAl07, what would be a better title?

Rod

 

[BigAl07]

@BigAl07, what would be a better title?

Rod

Fly Away, after RTH cancelled and AC was in Atti Mode

 

[RadRocket]

Yes,

@RadRocket,
Are you going to look for it?
Drifting at 8 miles an hour, with 80% battery, and it wasn't trying to come back, it still would have auto landed?
8 mph for about 15-20 mins, dang that sucks.

@BigAl07, what would be a better title?

Rod

I'm looking for it

 

[With The Birds]

It was your third flight on litch- how many flights do you have in DJI GO?

My advice to people is always to get some stick time and attain comfort flying in one app before venturing into other flight apps.

You could probably have brought your AC home if you understood what was happening. The phantoms almost fly themselves until you are caught off guard.

 

[RadRocket]

Fly Away, after RTH cancelled and AC was in Atti Mode

I don't mind changing the title to exonerate litchi. However if you look at data you see it was in pgps after RTH cancel
I understand you want to point the finger at me but never had a problem cancelling RTH with go when drone was near....just saying.

 

[RadRocket]

It was your third flight on litch- how many flights do you have in DJI GO?

My advice to people is always to get some stick time and attain comfort flying in one app before venturing into other flight apps.

You could probably have brought your AC home if you understood what was happening. The phantoms almost fly themselves until you are caught off guard.

I just took off why would I want to land

 

[RadRocket]

It was your third flight on litch- how many flights do you have in DJI GO?

My advice to people is always to get some stick time and attain comfort flying in one app before venturing into other flight apps.

You could probably have brought your AC home if you understood what was happening. The phantoms almost fly themselves until you are caught off guard.

Hundreds