I would think with the GMP cub, the center line would be referenced through the horizontal stab at level flight with the correct CG; whether the center line will follow through the motor shalt is unknown due to possible motor down thrust / placement.... I checked my Sig plans and the engine shaft center line is well below the center line of the horizontal stab, so assume the center line is offset.
John M,
Last edited by John_M_; 03-21-2014 at 03:44 PM.