Phantom 4 Pro Flyaway

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I need some advice from professionals.
On March 23 during the flight gps module got out of order and wind started to blow the drone away. In a few minutes the signal was lost. Data from two latest flights can be found in this links:
Airdata UAV - Flight Data Analysis for Drones
Airdata UAV - Flight Data Analysis for Drones
It can help to identify wind direction and the latest location of drone until it lost the signal.
During the flight I didn’t take into consideration that the bigger the height the stronger the wind. When drone was about 1,2km away from take-off point I tried to get it back using Sport mode but it didn’t help.
I would be thankful for proper advice on the following questions:
  1. When gps module gets out of order and wind blows away the drone what is the possibility that gps module will start operating properly again and the drone will try to get back to take-off point?
  2. Is it possible to define approximate area of drone fall knowing battery charge left (21%), wind speed and direction?
  3. Am I right thinking that drone starts autolanding when battery charge decreases at the level of 10%?
 
Please upload your TXT flight logs here and post a link back here. You'll find instructions for locating your TXT flight log at that link.

In reply to your questions:

1) If the wind is not too strong and the GPS data is being used, the Phantom will try to return to the home point.
2) Yes. The wind is constantly changing, so this area could be quite large depending on what your flight log shows.
3) The drone will start auto landing when it calculates that it only has enough battery power to land.
 
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He should have been your first 3/23 wasn't a few hrs ago like mine was I was a complete newb by the time I came back home from looking for it ,starting a thread on it , uploading the flight logs then going to where he said 7-8 hrs had past but he was spot on.
 
He should have been your first 3/23 wasn't a few hrs ago like mine was I was a complete newb by the time I came back home from looking for it ,starting a thread on it , uploading the flight logs then going to where he said 7-8 hrs had past but he was spot on.
It's a rarely visited place. Difficult terrain, forests and swamps.
 
Last edited:
On March 23 during the flight gps module got out of order and wind started to blow the drone away. In a few minutes the signal was lost. Data from two latest flights can be found in this links:
During the flight I didn’t take into consideration that the bigger the height the stronger the wind. When drone was about 1,2km away from take-off point I tried to get it back using Sport mode but it didn’t help.
It will take time to analyse the data properly.
But the data seems to be telling an interesting story.
While you were using sport mode, you weren't flying towards home.
This used up battery quickly without bringing the Phantom much closer.
I don't think it's correct to say that your Phantom flew away.
It appears that it was under your control and you flew it away.

It looks like there may have been a problem with GPS but this is only for the last 5 seconds of the recorded flight data.
Looking at the way you were having trouble flying towards home, I don't think this would have made much difference to the outcome.
 
I'm a video hobbyst, not professional like msinger o meta, but i'm curious hahaha. PhantomLog didn't say "GPS malfunction" or something in the last seconds... only say "satellite positioning off" and in these moment ATTI mode was engaged. Seems like the pilot has activated ATTI mode manually.

Perhaps you miss the switch position and you manually (by mistake) put P4P in ATTI mode. I'm wrong?
 
I'm a video hobbyst, not professional like msinger o meta, but i'm curious hahaha. PhantomLog didn't say "GPS malfunction" or something in the last seconds... only say "satellite positioning off" and in these moment ATTI mode was engaged. Seems like the pilot has activated ATTI mode manually.

Perhaps you miss the switch position and you manually (by mistake) put P4P in ATTI mode. I'm wrong?
Back at 6:45 the pilot switched to atti for 0.5 secs when switching to Sport.
That gave no warning of any GPS error.
At 9:32.9 we see the message Satellite positioning off. Fly with Caution, 1 second after the Phantom goes into atti mode.
I was assuming this indicated a positioning error but would have to do a test flight to confirm what message (if any) shows when you manually select atti mode.
 
Confirmed ... when you switch to atti mode, you don't get the Satellite positioning off. Fly with Caution message.
This is the same message you get when you first power up and the Phantom hasn't acquired enough sats to fix the position.
 
Confirmed ... when you switch to atti mode, you don't get the Satellite positioning off. Fly with Caution message.
This is the same message you get when you first power up and the Phantom hasn't acquired enough sats to fix the position.
Ok, so there's no wrong input or accidental switch to A mode from user. Thank you Meta4!
 
I wonder how well the find my drone options will work now in the moment for this type of thing.
 
On March 23 during the flight gps module got out of order and wind started to blow the drone away. In a few minutes the signal was lost.
It appears that you flew downwind at high altitude in a strong tailwind.
Your drone easily achieved its max speed of 17 metres/sec on the outward leg at 4:00 at an altitude of 267 metres.
When it went to RTH from 5:57 - 6:45, it was traveling in the correct direction towards home but going slowly into a headwind.
This shows at around 6:35 where you could only make 3.5 m/s letting RTH do the driving (with no stick input)
At 6:45 you took over and attempted to pilot it home in Sport mode.
Sport mode goes faster ... but eats the battery faster too.
You went off course, heading more north rather than northwest, reaching 8 m/s around 7:34 with full right stick forward.
You briefly touched full sport speed of 22 m/s around 7:48 (31% battery).
This would be where you turned back to the east, away from home and started losing signal
At 8:15 you are back in RTH using full right stick and making 4.8 m/s towards home (28%) and still up 200 metres high.
You changed to Sport mode again at 8:33 (26%) and managed to get back to 7 m/s but you went off course again and did not keep the speed up.
From 9:31 - 9:36 the Phantom went into atti mode and the reason for this is not clear.
But the battery is now at 21% and you are still 925 metres downwind from home and at an altitude of 100 metres when the record ends.
i-wddz3jx-XL.jpg

It's not clear why the recorded data stops there but if you lost signal, the Phantom would have hovered (in atti it would have drifted) for three seconds and then reentered RTH (but only if it had GPS again).
If it stayed i atti, it would have drifted downwind until critical low battery level and autolanded then.
If it regained GPS, it would have gone to RTH but made very little headway and also autolanded when critical low battery level was reached.
I wouldn't like to guess where it will have come down and wherever it is, there are a lot of trees for it to be lost in.

Flying a large distance downwind at high altitude is always going to make for problems coming home and is something all flyers should avoid.
Looking at how the Phantom managed when in RTH, it appears that you could have brought it back if you just kept the right stick forward and reduced height as much as would be safe.
Sapping the battery in Sport mode was not a good move but might have worked out if you reduced altitude and steered straight towards home.
Going off course twice was the biggest problem and even though you ran into an issue with GPS and atti mode right at the end, I think it was your navigation and piloting that caused the loss of your Phantom.
 
I wonder how well the find my drone options will work now in the moment for this type of thing.
Any find my drone feature can only give you the last recorded location of the drone.
Sometimes that's where it is.
Sometimes there are enough clues to tell where it was going after signal was lost (behind obstacle RTH situations) and terrain mapping can help find a crash site or the course of drift can show a line to search for a landing spot.
And sometimes there are too many uncertainties (like this case) to know where it is now.
 
It appears that you flew downwind at high altitude in a strong tailwind.
Your drone easily achieved its max speed of 17 metres/sec on the outward leg at 4:00 at an altitude of 267 metres.
When it went to RTH from 5:57 - 6:45, it was traveling in the correct direction towards home but going slowly into a headwind.
This shows at around 6:35 where you could only make 3.5 m/s letting RTH do the driving (with no stick input)
At 6:45 you took over and attempted to pilot it home in Sport mode.
Sport mode goes faster ... but eats the battery faster too.
You went off course, heading more north rather than northwest, reaching 8 m/s around 7:34 with full right stick forward.
You briefly touched full sport speed of 22 m/s around 7:48 (31% battery).
This would be where you turned back to the east, away from home and started losing signal
At 8:15 you are back in RTH using full right stick and making 4.8 m/s towards home (28%) and still up 200 metres high.
You changed to Sport mode again at 8:33 (26%) and managed to get back to 7 m/s but you went off course again and did not keep the speed up.
From 9:31 - 9:36 the Phantom went into atti mode and the reason for this is not clear.
But the battery is now at 21% and you are still 925 metres downwind from home and at an altitude of 100 metres when the record ends.
i-wddz3jx-XL.jpg

It's not clear why the recorded data stops there but if you lost signal, the Phantom would have hovered (in atti it would have drifted) for three seconds and then reentered RTH (but only if it had GPS again).
If it stayed i atti, it would have drifted downwind until critical low battery level and autolanded then.
If it regained GPS, it would have gone to RTH but made very little headway and also autolanded when critical low battery level was reached.
I wouldn't like to guess where it will have come down and wherever it is, there are a lot of trees for it to be lost in.

Flying a large distance downwind at high altitude is always going to make for problems coming home and is something all flyers should avoid.
Looking at how the Phantom managed when in RTH, it appears that you could have brought it back if you just kept the right stick forward and reduced height as much as would be safe.
Sapping the battery in Sport mode was not a good move but might have worked out if you reduced altitude and steered straight towards home.
Going off course twice was the biggest problem and even though you ran into an issue with GPS and atti mode right at the end, I think it was your navigation and piloting that caused the loss of your Phantom.

I'm confused why it switched to ATTI, when the satellite count was so high.
 

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