Juan de la Cierva

Juan de la Cierva (21 September 1895 –  9 December 1936) was a Spanish civil engineer and pilot. His most famous accomplishment was the invention in 1919 of the Autogiro, a type of aircraft that later came to be called an autogyro. After four years of experimentation, la Cierva developed the articulated rotor which resulted in the world's first successful flight of a stable rotary-wing aircraft in 1924 with his La Cierva C-6 prototype.
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