Juan de la Cierva

Juan de la Cierva was a Spanish aeronautical engineer and pilot. His most famous accomplishment was the invention of the autogyro in 1923. It was a predecessor to the modern helicopter.

He was involved with a Cierva Autogyro Company

His craft used a tractor-mounted forward propeller and engine, a rotor mounted on a mast, and a vertical stabilizer. His first three designs the C.1, C.2, and C.3, constructed by Parnall were unstable. His fourth design, the C.4, was successful.

During the Spanish Civil War, he supported Francisco Franco's side. He died in a fixed-wing plane accident.