Maybe I miss something, but with the hoist line out in the rudder house – doesn´t the line tension prohibits the rudder turning?

The reasons for my configuration were three: two lines to keep the rudder in position at speed (not forced up by the water pressure), to keep the lines in center where they are not affected by the rudder angle, and to keep the rudder system in place without any added hardware.

Furthermore, on the prototype the bottom of the cylinder is faired into the keel to minimize the turbulence – as is the leading edge of the rudder blade. On most sea racers or surfskis the bottom section where the rudder goes (3 ft in under the stern) is fairly flat for the width of the cylinder, and even at max angle (which for a rudder blade without a leading skeg is approx 20°) the out-of-fairness of the cylinder bottom is very small.

BTW, the actual building plans are copyrighted – but ideas are not. Information should be free and ideas open for other to improve upon.