An external adjustable ballast system for keeled sailboats comprising a
weight that is designed for low hydrodynamic drag, mounted through a beam
to a shaft running down the leading edge of the fin keel. Turning the
shaft moves the weight to optimize hull trim, both fore/aft and
athwartships, for a particular point of sail. If the weight and beam are
shaped as a lifting body and mounted to the shaft such that it pivots as
it rotates to optimize angle of attack, the dynamic balancing component
can allow for a lighter weight. Ballast weight and beam can be raised or
lowered to optimize performance for expected wind conditions. The leading
edge of the fin keel is a rotatable non spherical shaft. When rotated,
the shaft creates an asymmetric cross section which improves hydrodynamic
efficiency of the keel.