French aeronautical engineer who designed and flew a prototype of the helicopter. In 1907 he was successful in completing the first manned helicopter flight by flying one-foot (.3048 m) off the ground and hovering for 20 seconds. On later flights he acquired a height of 5 feet and (1.524 m) was timed at 6 miles per hour (9.656 km/hour). The two-rotor machine measured 40 ft (12.2 m), weighed 573 pounds (260 kg), and was powered by a 24-horsepower Antoinette engine. Its landing gear comprised 4 bicycle tires.