So this is worrying. I took off and flew about 400 feet away when I lost gps signal and I got compass errors. I flew it back and it got gps signal back. I recovered safely but I'm worried about it on other flights. I flew immediately afterward and nothing happened. Hopefully I can find the problem so I can avoid it in the future. Thanks in advance for any advice! I can also submit the flight record if you need.

Are you flying in a crowded city environment? GPS works pretty much everywhere unless there are a lot of tall buildings around you. Or have you fitted any after-market accessories to the aircraft?

It would be good to know what model Phantom you have and what kind of area you were flying in.

Did you really lose GPS signal or did your Phantom switch to attti because of conflicting data coming from the compass and GPS?
You can look closely at the flight data to work out what really happened.
Go to http://www.phantomhelp.com/LogViewer/Upload/
Follow the instructions to upload your flight record and it will give you a full display of everything that happened.

I was flying in a rural area with about 400 foot cliffs half a mile away. No accessories on the phantom. I have a phantom 3 advanced. One of the only things I can think of is that there is a state park nearby and there might have been a geofence blocking me. I will post the flight record soon.

If there was a Geofence, you probably would have got a warning on your screen, with a dialog box asking you to accept 2 conditions before continuing the fly. I've been getting that quite a bit lately, but always in urban environments.

Also, I have lost GPS lock many times while flying, for various reasons. I don't freak out because I can fly in ATTI mode.

Chris

random flier Posted at 2016-7-24 01:16
I was flying in a rural area with about 400 foot cliffs half a mile away. No accessories on the phan ...

There is no system that blocks GPS reception.

Geebax Posted at 2016-7-23 19:45
There is no system that blocks GPS reception.

not yet anyhow..

http://www.usatoday.com/story/ne ... west-june/85562276/

http://www.militaryaerospace.com ... ite-navigation.html

good luck and have fun flying!

random flier Posted at 2016-7-24 01:16
I was flying in a rural area with about 400 foot cliffs half a mile away. No accessories on the phan ...

State parks aren't geofenced and a geofence is like a wall in the air - it has no effect on compass or GPS.
That you had compass errors and lost GPS sounds very much like compass error causing your Phantom to switch to atti mode rather than losing GPS sats.
Checking the flight data as I suggested previously would confirm the actual casue.

One possibliity is compass calibration in a (magnetically) bad area before the flight.