Loss of altitude during FW transition (talisitter quadplane)

ArduPlane VTOL Plane
1

I have seen other posts about this and even posted an ask for help some time ago but have found no sound soution or suggestions. I have a tailsitter quadplane (no control surfaces) and experience a large loss of altitude during transition. See attached graph showing alt in green, nav/pitch in red and pitch in blue.

Some info provided in other old threads reference TRIM_ARSPD_CM, which I have set to 1600cm/s, ARSPD_FBW_MIN which I have set to 25m/s and Q_TRAN_PIT_MAX which I have set to 3. None seem to be out of whack so looking for some help/suggestions. Why the heck is it pitching down so much during transition? Do I need to lower the target speeds? Is it diving because it thinks it is stalling? Thanks for any input! Params attached

alt
alt1741×1145 160 KB

swan feb 19.param (25.0 KB)

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In reviewing the logs in more detail, it seems the pitch down is after the transition is complete. I also notice the airspeed doesn’t increase as quick as the GPS speed. probably because the pitot is at such an extreme AOA for awhile. Maybe that is why it is pitching down? Even though it has good airspeed according to GPS, it is not seeing enough on the airspeed sensor? In this case, maybe a higher Q_TRAN_PIT_MAX to allow it to pitch over quicker to get air into the pitot quicker? But then maybe it will pitch down too much and drop even more alt? My head hurts. I wish it was easier to setup the simulator.