3.6 QuadPlane - horizontal motor turned off during transition to plane

Hey, we have performed our first few tests of VTOL transition with 3.6 firmware. First AUTO mission was perfect (VTOL takeoff, few waypoints and VTOL land).
During second attempt (same mission) our horizontal motor just turned off few seconds after transition has started. RCOU.C3 just went to 1000. I’ve tried QRTL but I was behaving strangely so I landed using QHOVER.

It’s not a problem with motor or ESC, so what went wrong? Logs: https://www.dropbox.com/sh/1svs0v01da784p5/AAAvEPE6_OFF6VH6J_4RDotoa?dl=0

I can upload a footage from tail camera if needed (all motors are in frame).

Thank you for helping me and thanks for new firmware!

I’m confused. There are new parameters, for example: Q_M_THST_HOVER, right? In my logs you can see that there’s no parameter, instead I have Q_THR_MID, which is old if I’m correct. So I was flying on new firmware without some parameters? HOW?

Mission planner does not necessarily have all the latest parameters and sometimes need to be updated. Once in MP use Ctrl-f and then select “param gen”. Failing that you will need to use another GCS, mavproxy or CLI.

Your forward motor going off after a transition sounds weird. Maybe try a RC calibration and make sure the throttle is working correctly (not reversed etc). How did you do the transition was it in auto as well? Try doing a manual transition ie takeoff in qloiter/qhover and switch to FBWA 2-3 mistakes high.

Also be careful not to arm the aircraft and go to RTL, as this will launch the aircraft from the ground.

@Ekci - just curious, when you say “First AUTO mission was perfect (VTOL takeoff, few waypoints and VTOL land).”, was it all in quad mode or did you actually transition to fixed-wing? I’m having troubles to run an AUTO mission with VTOL takeoff + waypoints, in quad mode only. The aircraft just won’t start navigating to the waypoint after it takes off.