... Hydrofoils operating at shallow depths ( e.g. keels and rudders) will be affected by the interactions between the lifting surfaces and the free surface. This problem is approached computationally and experimentally by examining the simple case of a surface-piercing hydrofoil operating at steady...

... perform best in the close­hauled condition in true wind speeds in excess of about 15 knots, or whether the yacht must perform best in wind speeds not exceeding 15 knots, in which case no differentiation is necessary between the different points of sailing. subscript waterline lifting surface...

... The use of the nonlinear, steady vortex-lattice technique to treat close-coupled sails is described. The sails are modeled as highly cambered, twisted lifting surfaces. The aspect ratio and planform can be arbitrary. The technique is limited by the angle of attack as long as separation occurs...