Phantom 4 Pro Flyaway

[Meta4]

Yes, it was enabled

If there are no obstacles to worry about, you gain extra speed by disabling obstacle avoidance.

 

[Meta4]

It flew away, and there was problem with GPS. After that problem it start to fly away from me and in a few seconds signal was lost.

Flyaway suggests that the Phantom took off on its own and was not able to be controlled.
That did not happen in this case.
The Phantom was perfectly controllable right up to the time it went to atti mode but you didn't bring it home.
After it went to atti mode, it was still controllable but piloting it in a strong wind requires more skill and practice.

 

[bkushner]

I remember your post about that. It was in ATTI for just few moments right? I wander would Litchi, GS or Autopilot mission recover from that.

Yes it went into Atti mode showing like 19 sats...Flight data showed this GPS Mismatch...It was a hard to control atti as well. And map said I was 3 blocks in one direction while I was one block in another. One thing I suspect is it happened right after an IMU calibration..and I wonder if I did something wrong there. Sent the data and questions to DJI never heard back.

 

[KevMo Photog]

If there are no obstacles to worry about, you gain extra speed by disabling obstacle avoidance.

Are you sure about that in P Mode Meta4? Now I know when it's close to something it will slow and move cautiously but as soon as it's up and out and on it's way it does the full 25-30mph on mine. And in Sport Mode Object Avoidance is off anyway. Very sorry this dude has lost his bird btw. That sucks! Sounds like he underestimated the wind and then was streering off because it is so touchy if you yaw at all in Sport Mode. But also a concern with having a sattelite issue or GPS disconnect!

 

[Meta4]

Are you sure about that in P Mode Meta4? Now I know when it's close to something it will slow and move cautiously but as soon as it's up and out and on it's way it does the full 25-30mph on mine.

I'm certain because I need speed and range for my photography and there's nothing to hit where I fly.
I get 36 mph in still air with OA off and slower if it's on.

 

[KevMo Photog]

I'm certain because I need speed and range for my photography and there's nothing to hit where I fly.
I get 36 mph in still air with OA off and slower if it's on.

Wow! Im gonna have to revisit that for sure as that added speed will help some shots too! Instead of going full blown Sport Mode. Thx man!

 

[msinger]

fuzzylogic, as Meta4 explained above, there are two possible outcomes. Your Phantom either continued to drift further away from the home point and auto landed or it switched back to P mode at some point and tried to fly back to the home point.

Assuming the Phantom stayed in ATTI until it landed, I'd recommended you search between the following points:

59.549439, 28.106388 (last point in your flight log)
59.550014, 28.110642

The red line in the image below is the path between those two points.

After your remote controller disconnected from your Phantom, it would have started to auto land after 3 seconds. Since the wind was strong (or at least gusty at the end of the flight log), your Phantom would have been moving further away from the home point (along that red line if the direction of the wind did not change) as it auto landed.

 

[fuzzylogic]

fuzzylogic, as Meta4 explained above, there are two possible outcomes. Your Phantom either continued to drift further away from the home point and auto landed or it switched back to P mode at some point and tried to fly back to the home point.

Assuming the Phantom stayed in ATTI until it landed, I'd recommended you search between the following points:

59.549439, 28.106388 (last point in your flight log)
59.550014, 28.110642

The red line in the image below is the path between those two points.

View attachment 80641

View attachment 80643


After your remote controller disconnected from your Phantom, it would have started to auto land after 3 seconds. Since the wind was strong (or at least gusty at the end of the flight log), your Phantom would have been moving further away from the home point (along that red line if the direction of the wind did not change) as it auto landed.

Wow, thanks! It will help me a lot!
One more question - If I set Retrun-to-Home if RC signal lost in DJI GO settings what will drone do if it has gps error? Will it land automatically in current location or will drift by the wind?

 

[msinger]

if RC signal lost in DJI GO settings what will drone do if it has gps error?

If the drone is flying in ATTI mode due to unusable GPS data, it'll auto land at its current location after 3 seconds. When in ATTI mode, it's not able to hover in place. That means it would drift with the wind as it auto lands.

 

[neven]

If the drone is flying in ATTI mode due to unusable GPS data, it'll auto land at its current location after 3 seconds. When in ATTI mode, it's not able to hover in place. That means it would drift with the wind as it auto lands.

If GPS is regained during that process what will happen? Would it proceed with GPS assisted autoland or switch to RTH mode?

 

[msinger]

If GPS is regained during that process what will happen? Would it proceed with GPS assisted autoland or switch to RTH mode?

I'm not sure since I've never seen a log where that happened. If already in the process of auto landing, I'm assuming the Phantom would hold its current location and continue to auto land.

 

[sar104]

I'm not sure since I've never seen a log where that happened. If already in the process of auto landing, I'm assuming the Phantom would hold its current location and continue to auto land.

And it's not going to make much difference in this scenario, since in GPS mode it would not have moved very fast or for very long against the wind before autolanding anyway.

 

[neven]

And it's not going to make much difference in this scenario, since in GPS mode it would not have moved very fast or for very long against the wind before autolanding anyway.

It makes huge difference if that happens in autonomous flight when during 20 minute mission I only have signal in first and last 30 seconds.

 

[sar104]

It makes huge difference if that happens in autonomous flight when during 20 minute mission I only have signal in first and last 30 seconds.

In that case it certainly would make a big difference. I was referring to the OP's situation.

 

[neven]

In that case it certainly would make a big difference. I was referring to the OP's situation.

I agree with you on that one.

I had few unexpected ATTI modes with my P3P caused by compass errors but they were during LoS flights with good signal. It really doesn't take too much skill to bring it back but panic is your worst enemy. If you stay calm and concentrated you'll probably make it home. If you panic you are doomed.

 

[pe9999]

That is not the answer I want to hear

When doing out of LOS autonomous missions with no connection between AC and RC, you need rock solid GPS. If it glitches it ain't coming back.

*before someone gives me the lecture how those are not alowed let me say that I have all permits for doing them

What kind of permits you have?

 

[neven]

What kind of permits you have?

National agency for civil aviation. S&R operations.

 

[AlanTheBeast]

Yes it went into Atti mode showing like 19 sats...Flight data showed this GPS Mismatch...It was a hard to control atti as well. And map said I was 3 blocks in one direction while I was one block in another. One thing I suspect is it happened right after an IMU calibration..and I wonder if I did something wrong there. Sent the data and questions to DJI never heard back.

"GPS Mismatch"? What does that even mean? Does it mean:

• GPS and GLONASS have different solutions?
• That the PR's don't solve within a certain spherical error ball?
• That DJI do not use a Kalman filter integrating GPS, GLONASS, IMU's, Mag compass and Baro?

(Well - pretty clear the last one is correct )

 

[Ranger 007]

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%?

SEND IT BACK TO DJI IT IS DEFECTIVE

 

[sar104]

"GPS Mismatch"? What does that even mean? Does it mean:

• GPS and GLONASS have different solutions?
• That the PR's don't solve within a certain spherical error ball?
• That DJI do not use a Kalman filter integrating GPS, GLONASS, IMU's, Mag compass and Baro?

(Well - pretty clear the last one is correct )

Just based on looking at the circumtances in which that message has been reported by various users, it typically seems mostly to be associated with high winds. I wonder if it is just a badly phrased message and the FC is actually simply reporting that it cannot hold the desired location or course.