[Phil Hertzler]

I think I found the answer with the help of “Physics of Sailing” by John Kimball.  My cable from the centerboard to the cylinder is 2:1 and I suppose the increased diameter of the drum that takes up the pennant provides the leverage.  The equation is f = 2R/r * F where f is the force of the centerboard, r is the radius of the cylinder that winds the wire and R is the radius of the drum (minus the radius of the cylinder).  If R = 8″ and r = 1″ (or any ratio thereof) than raising a centerboard weight of 96 pounds would require 6 pounds of pull on the pennant, increasing as turns are taken up on the drum.  Sound reasonable?

[Phil Hertzler]

Hi Richard,
Check out the Cal 20.  It is about the size of the Scot but has a keel and self-bailing cockpit.  There are several fleets in Southern California that race.

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