Hey guys, I wanted to tell you a story that all pilots will find important and something to keep in mind when flying far away. Today, I was flying my P4 about 1 mile away, just flying for fun around the 60 acres park. When I took off, it reminded me about compass issues and I already calibrated the compasses, and I thought that I would get better satlelite signal when I was up in the air. Usually when you lose signal, the drone would automaticly come back automatically. BUT* You always have to keep in mind that RTH is based on using the compass to get home. If you don't have any satellite signal, but still have the homepoint recorded, the drone will automaticly land once you lose signal and still don't have any satellite signal to get home. This is what happened today. For some reason when it landed, it still had 36 percent battery when I found it. I found it by the remote control finding the drone's signal and connecting it and it shows where the drone is. Here is the flight data:


So the lesson is don't fly too far is you don't have very strong compass signal. Or else you might lose your drone.

When I took off, it reminded me about compass issues and I already calibrated the compasses, and I thought that I would get better satlelite signal when I was up in the air.
It sounds like your compass was warning you that it detected magnetic interference near the launch point.
The most common source is launching from a reinforced concrete surface.
Ignoring this was your problem.
You should have moved the Phantom away from the magnetic interference it was warning you about.
A compass error will force the Phantom into atti mode and RTH won't be usable.
If you post a link to actual flight data, we can confirm whether my guess is correct.

To do that go to http://www.phantomhelp.com/LogViewer/Upload/
Follow the instructions there to upload your flight record from your phone or tablet.
Come back and post a link to the report it gives you.

So the lesson is don't fly too far is you don't have very strong compass signal.

The compass is never strong or weak.
The lesson is Don't launch from steel or reinforced concrete surfaces.
If the Phantom warns you of a compass error, move the Phantom away from the cause of the compass error.