openings (filed on April 2, 1952, granted on March 18, 1958) – Mechanical directional and trim control for helicopters (filed on August 16, 1951, granted on November 8, 1960) – Swash plate operating mechanism and combination with swash plate (filed on Mar 11, 1958, granted on April 4, 1961) – Helicopter rotor head (filed on July 29, 1958, granted on November 7, 1961) – Rotor and blade for rotorcraft (filed on December 27, 1956, granted on November 7, 1961) – Rotor head with collective pitch control (filed on July 2, 1958, granted on March 26, 1963) – Rotor with two joints in drive shaft (filed on January 30, 1961, granted on April 30, 1963) – Oscillation damper for the hub of a rotorcraft rotor and its combination with a rotorcraft (filed on October 16, 1975, granted on January 25, 1977) – Damping mechanism for the rotor hub of a helicopter for ground resonance and waddle and its combination with the rotor (filed on June 14, 1976, granted on February 14, 1978) – Wind turbine with drive train disturbance isolation (filed on April 22, 1980, granted on May 11, 1982) – Wind turbine with yaw trimming (filed on May 19, 1980, granted on October 12, 1982) – Minimization of the effects of yaw oscillations in wind turbines (filed on November 8, 1982, granted on May 7, 1985) – Variable speed wind turbine (filed on November 18, 1985, granted on September 22, 1987) See also Seawind Ocean Technology Gamma 60 wind turbine NASA wind turbines Floating wind turbine Anton Flettner Kurt Hohenemser Variable speed wind turbine Offshore wind power References External links Doman Helicopters Blue H Technologies Norwegian project Dr. Techn. Olav Olsen Seawind Ocean Technology 1921 births 2016 deaths American aerospace engineers Aviation pioneers Renewable energy Renewable energy technology Wind turbines University of Michigan College of Engineering alumni American expatriates in Italy