Trimming the plane

Hi, I am working on my Skywalker V2 plane with Mateksys F765-WSE. GPS is M8Q-5883 and airspeed sensor is ASPD-4525. To begin with I have ARSPD_USE = 0, and I am not using compass. This is my first Ardupilot aircraft. My Tx is Taranis X9D.

Flight modes are controlled with two switches acting as a six position switch.

Currently I am focusing on trimming the plane, and want to use SERVO_AUTO_TRIM. I have read about this parameter, but I am a bit uncertain about the order of proceedings.

I have made a small ordered list of actions to perform before I start tuning the plane, and hope someone would be kind enough to comment on it.

  • All channels to 100% in Tx.
  • Tx trims centered.
  • Control surfaces leveled with the plane’s flying surfaces.
  • Radio calibration done in MP.
  • Plane leveled on the table and accel Leveled in MP.
  • Servo output MAX and MIN values set to suitable control surface deflections.
  • Servo output TRIMs set equal to the Tx neutrals for Aileron, Elevator and Rudder.
  • Servo output TRIM to bottom position for Throttle stick.
  • SERVO_AUTO_TRIM parameter set to 1.

Then:

  • Take off in Manual mode. Do not touch trims on Tx.
  • Switch to FBWA and fly around a few minutes trying to hold the plane level.
  • Land and check Servo output TRIM values.
  • If TRIM values are too far away from Tx neutrals (how much?), do mechanical adjustment of links.

Could anyone please comment on this? It would be very helpful.

Thanks, Helge.