Mavic fly away, changed home point during flight

ronjacobs · Feb 6, 2017

When I was flying I decided to use RTH and pressed the button. (Home point was set during take of, 17 satelites, did the calibration) My mavic flew away from me landing 1 mile away. When looking at the log on my phone I noticed that the home point was altered during flight. It landed on that new home point. Why or how did the home point change?????
Any clues??
Happened to somebody??
Did I do something wrong?

msinger · Feb 6, 2017

Are you using DJI GO 3.1.2 on an Android device? If so, that's a known issue. Install DJI GO 4.

shvncrvn · Feb 6, 2017

I am talking under correction here, but the home point you chose on your map using the app uses your phones GPS co-ords or it's perception of it at that specific time (the phone also needs to acquire satellites to determine where it is). If this has not been updated to indicate your latest location it will send the wrong co-ords to the aircraft.

ronjacobs · Feb 6, 2017

Phantom Log Viewer - PhantomHelp.com

Look at 7 m 10.8 Home point updated ?????
The home distance changes from 2.2 ft to 3953.6 ft

AyeYo · Feb 6, 2017

I think another question that needs to be asked is: why did you use return to home in a non-emergency situation?

msinger · Feb 6, 2017

Ah, yes, you were using DJI GO 3.1.2. Either downgrade it or install DJI GO 4.

ronjacobs · Feb 6, 2017

msinger said:
Are you using DJI GO 3.1.2 on an Android device? If so, that's a known issue. Install DJI GO 4.

Where do I find that number?? in the app? I'm using android.

ronjacobs · Feb 6, 2017

AyeYo said:
I think another question that needs to be asked is: why did you use return to home in a non-emergency situation?

Just to try that function.

Chris J · Feb 6, 2017

AyeYo said:
I think another question that needs to be asked is: why did you use return to home in a non-emergency situation?

I can't really help the OP here, but I'd like to know why AyeYo is implying that RTH should only be used in an emergency situation. It's a function programmed into the unit, and it should be work whether you are in an emergency situation or not. Once I find a place big enough to test out all the functions of my mavic safely, I plan to test RTH. Will I be in an emergency situation? Hopefully not. Do I still expect it to work properly? Of course.

msinger · Feb 6, 2017

ronjacobs said:
Where di I find that number?

You can find the DJI GO version in the "General Settings" --> "About" section of DJI GO. There is no need to check though. Your flight log shows you were using version 3.1.2.

AyeYo · Feb 6, 2017

ronjacobs said:
Just to try that function.

As far back as the original Phantom, RTH has proved to be a crap shoot. It's gotten better over the years, but you're still rolling the dice every time you hit that button. It should not be used as a "I just didn't feel like flying back manually" function. There are too many things that need to be in order for it to work and it's too easy for one of them to fail. Always ask yourself before you hit that button whether it's worth the risk over simply flying back manually.

ronjacobs · Feb 6, 2017

ronjacobs said:
Where do I find that number?? in the app? I'm using android.

Found it. Installed DJI GO, with no nummber from google play store.
Going to install DJI GO 4 now.
Thanks

ronjacobs · Feb 6, 2017

AyeYo said:
As far back as the original Phantom, RTH has proved to be a crap shoot. It's gotten better over the years, but you're still rolling the dice every time you hit that button. It should not be used as a "I just didn't feel like flying back manually" function. There are too many things that need to be in order for it to work and it's too easy for one of them to fail. Always ask yourself before you hit that button whether it's worth the risk over simply flying back manually.

You are absolutely right. But in case something happens I want my drone to come back to me (in case of losing connection).

ronjacobs · Feb 6, 2017

msinger said:
You can find the DJI GO version in the "General Settings" --> "About" section of DJI GO. There is no need to check though. Your flight log shows you were using version 3.1.2.

Great, thanks.

Cyberpower678 · Feb 6, 2017

ronjacobs said:
Phantom Log Viewer - PhantomHelp.com

Look at 7 m 10.8 Home point updated ?????
The home distance changes from 2.2 ft to 3953.6 ft

Use DJI GO 4 instead. DJI GO 3 is not meant for the Mavic.

Cyberpower678 · Feb 6, 2017

HealthyDrones.com - Innovative flight data analysis that matters

Here's the same log on HealthyDrones.

Cyberpower678 · Feb 6, 2017

Here's to outdated browser data. I see the issue is resolved already. Posted my suggestion when the latest result was the flight log you posted.

ronjacobs · Feb 6, 2017

shvncrvn said:
I am talking under correction here, but the home point you chose on your map using the app uses your phones GPS co-ords or it's perception of it at that specific time (the phone also needs to acquire satellites to determine where it is). If this has not been updated to indicate your latest location it will send the wrong co-ords to the aircraft.

I thought the arcraft itself was connecting to satelites and deriving its home point. Never heard of phone sending home point to mavic. Also, the initial homepoint was set right. It showed on the map. It changed somehow during flight.

msinger · Feb 6, 2017

ronjacobs said:
I thought the arcraft itself was connecting to satelites and deriving its home point. Never heard of phone sending home point to mavic.

It does, but the home point will switch to your mobile device's current location if you choose to return to the current location when initiating RTH.

ronjacobs · Feb 6, 2017

Cyberpower678 said:
Here's to outdated browser data. I see the issue is resolved already. Posted my suggestion when the latest result was the flight log you posted.

Well, for me still not resolved. Is the DJI GO 4 app the solution? What can I read/learn from the Healthy Drones flight data? Will it happen again and what to do.
You see, I am a novice, just got my mavic last week.