We are having an issue with altitude loss happening after the DO_VTOL_TRANSITION mission command is used. I am attaching videos of the problem here (screen recording from SITL) as well as the logs here.
The problem happens both in SITL and on the real drone in flight.
The altitude drop with a regular waypoint in SITL was 17m (repeated 3 times and was 17 each time), whereas with a LOITER_TO_ALT it was 5-6m (also repeated 3 times). Unfortunately despite working in SITL for me, replacing that waypoint with a loiter_to_alt did not work in flight with the real drone. Although there was no altitude drop, the drone reached the loiter_to_alt point in fixed-wing mode (transitioned fine, no altitude drop) but at the point it simply stopped in VTOL mode and hovered there. Maybe this is because I have Q_GUIDED mode enabled, but I also have Q_GUIDED mode enabled in SITL, and it wasn’t happening.
I also think that most physical factors can be eliminated as being causes of this issue, because the drone (and SITL) do a perfect VTOL to fixed-wing transition right after the VTOL_TAKEOFF. (Although no DO_VTOL_TRANSITION is used there - maybe this is a clue?).
Any ideas for how we could resolve this issue, and have the drone transition from VTOL to fixed-wing smoothly?