Quad copter always drifting 'home'

I’ve been struggling with some new drifting lately, i noticed it on my 2013 X4 a few weeks back and now with a larger 2014 X4 w/ new GPS (same APM however). At first i thought it was wind, but then there wasn’t any wind…

Anyway, it seems that the quad always drifts downward, towards me, in Simple mode. I then re-armed and launched again facing 180 degrees from my original position, and sure enough, the quad drifts ‘down’ towards me. This was in Simple mode in Stabilize & Alt. Hold, and the effect is visible in Land as well. Loiter works for the most part, though it has been choppy the last few flights (erroneous input?).

My trims are centered on transmitter, and I’ve gone through all offsets on transmitter to confirm nothing sneaky there. I’m on 3.1.4, I’ve calibrated radio and accel, even erased several times. The APM is mounted on a vibration dampening frame.

If anyone has some guidance on what to look for in the logs I’m hoping something will be there.


I should say that this drift ‘down/towards home’ occurs no matter the heading change with yaw. This is why I think is has something to do with APM or transmitter. However everything is zero’d on transmitter.

Please provide a logfile.

This is one from that flight. Towards the end of the flight time I just tried to tune it out with trim to just get some fpv testing done… I’m hoping this is prior to that.

I did erase and reflash when moving my apm to this frame setup, but I going to try a 3.2 beta. I wanted to check something out there anyway.

If you have a chance to show me what t look for in these logs i’ll dial in on it next time, i’m going to get some IMU log for vibrations as well (though i assume its ok with the setup i have, who knows)

Thanks for all your time.

Well good news, despite having erased and reflashed previously, i erased and flashed 3.2rc1. All the things that were having difficulty before like hover & autotune, works. went from the ground up, and after an autotune session and some trim adjustments i’m pleased with where i’m at.

On two occasions however when powering up the copter on level group, the horizon in apm planner/mission planner was skewed. accel calibration fixes it. Though i’m perturbed that it would be so off suddenly. On a previous frame there were some crashes due to bad gps, but who knows…

so far so good.