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.
De la Cierva was born in Murcia, Spain to a wealthy family. After several successful experiments with aviation as a boy, he eventually earned a civil engineering degree. He moved to England in 1925 where with the support of Scottish industrialist James G. Weir, he established the Cierva Autogiro Co.
At the outbreak of the Spanish Civil War, De la Cierva supported the forces of Francisco Franco, helping the rebels to obtain the De Havilland DH-89 'Dragon Rapide' which flew general Franco from the Canary Isles to Morocco. He died in an airliner accident near London at the age of 41. On the morning of 9 December 1936, he boarded a Dutch DC-2 of KLM at Croydon airfield, bound for Amsterdam. After some delay caused by heavy fog, the airliner took off at about 10.30 a.m. but it crashed on the roof of a building at the end of the runway and was set on fire.
Technology developed for the Autogiro was utilized by experimenters in the development of the helicopter, the first fully successful example of which, the FA-61, was flown in 1936 by Cierva Autogiro Company's licensee Focke-Achgelis. The Autogiro also led directly to the Cierva C.38 Gyrodyne, which utilized a powered rotor for hovering and low speed flight, and a side-mounted propeller for torque correction and propulsion in cruise flight. The Fairey Gyrodyne, first flown in 1948, established the superiority of this configuration over that of the helicopter, which De la Cierva consistently rejected as too mechanically complicated, even though he agreed with the requirement for hovering performance.
Variants
| Variant Name | Date | Builder Detail | |
| Cierva C.1 | 1920 | Experimental autogyro. | |
| Cierva C.2 | 1921-1922 | Experimental autogyro. | |
| Cierva C.3 | 1921 | Experimental autogyro. | |
| Cierva C.4 | 1922 | Experimental autogyro - the first to fly successfully | |
| Cierva C.6 | 1923 | The first autogyro to travel a substantial distance. | |
| Cierva C.8 | 1926 | Built in association with Avro. | |
| Cierva C.9 | 1927 | Built by Cierva in association with Avro. | |
| Cierva C.12 | 1929 | Built by Cierva Autogiro Co in association with Avro. | |
| Cierva C.17 | 1928 | Built by Cierva Autogiro Co in association with Avro. | |
| Cierva C.19 | 1929 | Two-seater autogiro built by Avro. | |
| Cierva C.24 | 1931 | Built by De Havilland. | |
| Cierva C.30A | 1933-34 | Built by Cierva Autogiro Co and Avro. | |
| Cierva Air Horse | 1948 | By Cierva Autogiro Co | |
| Cierva W.9 | 1945 | Experimental Helicopter by Cierva Autogiro Co. | |
| Cierva CR Twin | 1969 | Utility Helicopter by Cierva Autogiro Co and Rotorcraft. |