[paulk]

I read something, somewhere (Marcaj?) about how the shape of a fractionally rigged mast and sail was closer to the optimal leading edge shape than a masthead rig. The fractional rig supposedly creates a "better" vortex off the sails, which means going faster with the same sail area. It seems that a curved, (or "jointed",as it is in a fractional rig) leading edge works better aerodynamically than a single straight line (as a masthead rig would have). Airplane leading edges are often swept back, perhaps for this same reason?

 

[paulk]

Good luck, Bob, though have you considered getting some new sails? Carbon ones might scare a lot of competition into making mistakes.