Forces on sails to stay within the limitations of a craft's stability and power requirements, which are functions of hull (for boats) or chassis (for land craft) design. Sails derive power from wind that varies in time and with height above the surface. In order to do so, they are designed to adjust to the wind force for various points of sail. Both their design and method for control include means to match their lift and drag capabilities to the available apparent wind, by changing surface area, angle of attack, and curvature. Wind speed increases with height above the surface; at the same
1975–76 San Diego Sails season holding Portland's Bill Walton to 6 points and 11 rebounds, but Portland won 98-85. Despite the Sails' loss the ABA won 31 games against the NBA in that preseason, compared to 17 wins for the NBA. The ABA opened its 1975-76 season on October 24, 1975, and on that night the Sails hosted the Denver Nuggets before 3,060 fans. Denver's Ralph Simpson led all scorers with 30 points and Denver won 120-108. The next night the Sails began a long road swing by earning their first win in franchise history with a road victory against the Utah Stars. Bo Lamar