Fixed wing inverting altitude and crashes

Hi all,
Trying px4 on a fixed wing. This is flying ok as long as I stay in Manual mode.
As soon as I pass in Stabilized, or Mission or any assisted mode (tried each and repaired every time :wink: ), the wing gets upside down and dives to the grounds.
Even if I calibrate every sensor before each flight, the z axis is inverted. An example flight-crash log:

You can see my local position z reversed.
The model chosen in QgroundControl is a FX-79 buffalo wing.

Any idea would be welcome.

@david17 PX4 uses a NED(North East Down) coordinate system, so I don’t think your local position z is reversed.

What I see in the log is that it seems like your roll and pitch control surfaces might be reversed. You can see that the vehicle is not able to track the roll rate and pitch rate setpoints. Have you checked in stabilized mode whether the control surfaces are reacting in the right direction?

Thanks for answering so fast Jaeyoung-Lim. From what you said I remembered that I had to reverse the RC directions. I guess I should have check the wirings of the Buffalo. Looking at the reference page(Airframes Reference | PX4 User Guide) I could see that that model has the main 1 on the right aileron (the only frame like that!!). It’s too windy in France to try now, but I hope it’s the right analysis. Sure you were thinking about something like that?
Thanks again.