correcting myself... actually, the high aspect rudder doesn't reduce the
amount of drag, it just changes the "gear ratio" so to speak of the
so it doesn't have much effect on speed but it does lighten the
helm drmatically... the longer and skinner the blade, the less leverage the
blade has over the relatively longer tiller
--- In email@example.com, "etap28"
> I'll tell you what's
funny about those traditional catboats... if you make a high-aspect rudder, a
typical modern blade, the weather helm is mitigated hugely. Obviously if you
have a "barn door" sticking out the back, with about the same lever arm pulling
against the tiller as the tiller is pulling back, it's gonna hurt--especially
with a low aspect sail sticking out over one rail about 20 feet.
> Also, if you wanted to make a clever semi-balanced rudder, of a type
Bolger actually used on a lot of his designs, you could totally eliminate the
weather helm and hide that force vector in sideways torque against the rudder
> I used to preach this all the time to the traditionalist
cat boat types but nobody was all that interested . . . (PS I actually know
first hand that it works. I've had a few catboats, including a Woods HOle
Spritsail boat, one of about 3 in existence, and I made a nice foil shaped kick
up rudder for it and it sailed like a bullet... the absence of massive weather
helm obviously gets rid of a lot of drag).