On the Hydrodynamic Performance of Sailboards

Master's thesis in Naval Architecture & Offshore Engineering, University of California at Berkeley, 12/87.
Presented April 6, 1988 to the SNAME Northern California Section.
Awarded national SNAME Graduate Paper Honor Prize, 12/88.


The vortex lattice method is used to predict the forces on sailboard/fin combinations that plane at high Froude number (Velocity / (g*Beam)^0.5). Results compare well with existing analytical solutions and with experimental data for Froude numbers greater than 4, corresponding to board speeds greater than 20 knots. The analysis also predicts that a speed increase of 55% (from 39 to 60 knots) is achievable by an increase in beam. The paper describes the physical nature of planing, the mathematical model used and the effect of variations in both sailing trim and geometry (camber, rocker, vee, concavity and planform). In the appendices, the speed potential of a sailboard [generalization of Marchaj] and a method for fin optimization [under the influence of a partial end-plate] are discussed.

Last Update: 18 February 1997