Drift away and then spirals?

While flying the drone stopped at end one leg and just slowly drifted away. I recovered it manually. Went to pick up the flight from the last way point and the drone took off hesitated at height then headed to the way point doing small spirals! Very odd. Once it reached then way point it continued as normal.

It has done similar hesitations before but recovered but not this time.

26th July

P4Pro

IPhone X

2.78

Sounds like a GPS issue. Possibly compass, but I don’t think it would be that drastic.

Hello Thanks for reaching out. I would make sure you are using our latest version of our software and also the firmware version. Usually when your drone drifts away is that it has changed to GPS ATTI mode, a full manual control mode which is a fail safe when GPS connection has been lost.

As far as the spiral that is unheard of. I would definitely take a look at the flight logs to see what may be going on and to rule out a hardware issue.

Thanks!

Spiralling isn’t unheard of at all.
It is usually an indication of compass problems

Also Atti mode isn’t a failsafe when GPS is lost.
It’s what you have when there’s no GPS signal or when a compass error forces the Phantom to ignore GPS data because of a data conflict due to a compass error.

Now that sounds like it. I haven’t had a chance to look at the flight log yet, but I bet that’s it. I haven’t recalibrate the compass for ages.

GPS doesn’t have to be completely lost for ATTI to take over. If the GPS signal becomes unstable due to interference or loses the necessary number of satellites to maintain a fix ATTI will kick in. It’s called DGPS in GNSS terms and Float when GPS is not fixed. Essentially it is a way for the system to provide maximum stability in those conditions by eliminating them and the vision system to use the barometer for altitude. You can use whatever term you want, but it is a safety measure to try and keep the system as controllable as possible where otherwise you would be out of control and at the system’s mercy in poor conditions. You can also switch to it manually if needed or if you just want to semi-manually fly.

Well I had it out for a re-calibration yesterday and it seems to have done the trick. It just needs some body to point out the obvious sometimes.

Thanks