First, let me say that I am glad you found a solution to your problem. However, I do have a question that perhaps someone could shed some light upon. This takes the possibilities of any trim, setup or dissimilar wing incidence issues out of the equation and relates specifically to the assessment of a ground effect induced problem.

If I understand correctly, the contention is that ground effect was causing the left. Was this left in one axis or more than one? It seems as though you were discussing a yaw AND roll movement (which was corrected by your trim tab retarding the roll axis movement). I guess it was perceived as a roll more than yaw. If roll was part of the movement, is the roll the cause or affect? Even considering ground effect, what is producing the asymmetrical lift? Is the aircraft tracking with right side leading edge in front of the left (aircraft crabbing instead of straight)? I just don't understand how if everything was straight and true, the right wing (bottom wing at that) produce more lift than the left wing. I have reviewed P-factor, torque, and gyroscopic procession, along with tail-wheel -vs. - rudder effectiveness and can understand the movement based upon all of these things, but I cannot get my head around an asymmetrical lift produced specifically based upon ground effect. If all else is equal, shouldn’t ground effect be produced symmetrically?

Please let me know where I am going wrong and not seeing it through.

Thx,