Lilienthal, Otto (1848-1896)

German aviation pioneer who inspired US aviators Orville and Wilbur Wright. From 1891 he made and successfully flew many gliders, including two biplanes, before he was killed in a glider crash. Lilienthal demonstrated the superiority of cambered wings over flat wings - the principle of the aerofoil. In his planes the pilot was suspended by the arms, as in a modern hang-glider. He achieved glides of more than 300 m/1,000 ft, and gliding began to catch on as a sport. Lilienthal was born in Pomerania (then part of Prussia), and trained as an engineer. From studies of the flight of birds, he learned that curved wings allow horizontal flight without an angle of incidence to the wind, and that soaring is related to air thermals. Having shown conclusively that birds produce thrust by the action of their outer primary feathers, he built a powered machine with moving wing tips, using a carbon dioxide motor. The machine was not tested. Lilienthal's book Der Vogelflug als Grundlage der Fliegekunst/Bird Flight as a Basis for Aviation 1889 greatly influenced other aviation pioneers.