Hi Tim,
interesting construction. Some hints from our tri-tiltrotor experience:
I would choose an X-frame logic instead of H-frame logic, so that the torque of the propellers during forward-tranistion counteracts against disturbances at the roll axis. See: Tiltrotor support for plane and Tiltrotor support for plane
For the tiltservos you should each use a separate output (function 41)
Dont forget to set:
Q_ASSIST_SPEED 0 (tilted Motors cant help prevent stalling)
Q_TRANSITION_MS 0
Adjust the following parameters to your individual plane characteristics:
Q_TILT_MAX (Max. tiltangel while accelerating from hover to planflight and waiting, that FBWA_MIN will be reached)
Q_TILT_RATE_DN , Q_TILT_RATE_UP (degrees/second)
ARSPD_FBW_MIN xx (m/s, at thist airspeed the tiltable motors turns immediatly to plane mode and should be a little bit above stallspeed )
Be carefull: Do not accidentally switch directly from QHOVER to MANUAL MODE (instead FBWA) without enough speed or height above ground
Tiltrotor support for plane
Curious about your progress, good luck
Rolf