Juan de la Cierva
Juan de la Cierva y Codorníu (born September 21, 1895 in Murcia , † December 9, 1936 near London ) was a Spanish engineer and aviation pioneer. His research made a significant contribution to the development of the helicopter , which replaced the autogiro he had developed from the Second World War . In the meantime, gyroplanes are increasingly being used again, primarily by private pilots .
life and work
Juan de la Cierva was born as the son of the lawyer, mayor of Murcia and war minister of the second Spanish republic, Don Juan de la Cierva y Peñafiel . On December 10, 1919, he married María Luisa Gómez Acebo and had six children. At the age of 16 he was already calculating and constructing airplanes.
Aircraft construction
In 1910, Cierva began building aircraft with his friends José Barcala and Pablo Díaz. The three together founded the company BCD (for Barcala, Cierva and Díaz) in Madrid. As early as 1911 to 1913, BCD built double-deckers (BCD1 and BCD3) and a middle-decker (BCD2) with rotary engines from the Gnome company from France. In the period up to 1917, Cierva completed a civil engineering degree in road, canal and port construction in Madrid.
The joint company BCD presented a three-engine aircraft in 1918 with the BCD El Cangrejo . This was equipped with three red painted engines from Hispano-Suiza company , each of which had an output of 320 hp. With a take-off weight of around five tons, the aircraft reached an altitude of 6000 meters and a cruising speed of 160 km / h. It was destroyed on June 8, 1919 by a pilot's mistake. Then Juan de la Cierva acquired his own flight license.
Autogiro
In 1920 the first ideas for building the Autogiro , a gyroplane , matured . On June 20, 1920, the entry in the patent register and the entry of the Autogiro brand took place . However, there is also evidence that he took over the basic principle of the gyroplane from the Mallorcan Pere Sastre Obrador . Cierva's patent document dealt with the general design of a gyroplane, but also described a possibility of shortening the take-off distance by turning the rotor beforehand. His patent lists the coaxial rotor to compensate for the different buoyancy of advancing and retreating rotor blades, which, however, already proved unsuitable for this purpose in his first actually executed machine C.1 . The other experimental units C.2 and C.3 could not achieve a stable flight condition either.
Cierva C.4
It was only with the development of the flapping joint in 1922, which Cierva used in the C.4 and which was patented in 1923, that stable flight with a gyroplane became possible. This took place on January 17, 1923 during a test flight of the C.4 with the Spanish Lieutenant Gómez Spencer. Spencer made the first real flight 14 days later at Cuatro Vientos Airport, completing a four-kilometer circle in 3 minutes and 30 seconds.
The flapping hinges used for the first time in the Autogiro C.4 have been used in principle unchanged to this day. Some more modern designs replace the hinge with an elastic bearing of the blade root in combination with more elastic rotor blades made of composite materials.
Further development
In July 1923 the variant C.5 took off with a three-bladed rotor and by the end of the year Cierva was already working on the C.6 series . After the first flight in July, the first cross-country flight of the C.6 took place on December 12, 1924 under the command of Lieutenant Loriga. He took off from Madrid and flew to Getafe Airport , a distance of 12 kilometers. The gyroplane had a 110 hp engine and a total weight of 780 kilograms. With a climb rate of 10 m / s, a peak height of 6000 meters, a cruising speed of 230 km / h and a range of 530 kilometers, the model aroused great interest among the international military.
Juan de la Cierva was then able to fly over the English Channel between Lympne and Calais (around 40 kilometers) on September 18, 1928 in the Autogiro Cierva C.8L Mk.II at an altitude of 1200 meters and with a total flight time of 18 minutes . During the landings carried out here, de la Cierva proved that with his gyroplane you can take any approach angle between 15 and 80 degrees to the horizontal when approaching, and thus the landing distance can be reduced considerably. The distance between the touchdown point and the coasting distance was never more than 3 meters, although the autogiro continued its steep descent like a normal airplane and was only intercepted shortly before the touchdown point from a height of 1 to 2 meters.
The gyroplane demonstrated convincingly that it never got into the stall phase, as is common with fixed-wing aircraft. However, he still needed a longer take-off distance for take-off than for landing because the rotors could not be brought into the necessary rotation fast enough. Another problem was taking off on an uneven runway because the rotor blades often touched the tail unit and damaged it. In 1929 de la Cierva developed a tail unit that was protected from the rotor blades. In the same year, his American partner developed a device that drove the rotor faster during take-off and thus reduced the runway to 10 to 20 meters. An essential part of this was that when the lift speed was reached, the rotor drive was switched off and the gyroplane could continue to fly as before.
Foreign projects
Cierva emigrated to England in 1925 and founded the Cierva Autogiro Company of Great Britain Ltd. based in Southampton . Cierva carried out a number of his projects together with the British aircraft manufacturer Avro . In October, the two-seater model C.6-C received a civil license with the registration number G-EBTW. In 1926 the first C.6s were delivered to the Royal Air Force in England.
In 1928, Cierva laid the foundation stone for series production of the PCA-2 series in the USA with the founding of the Autogiro Co. of América in the USA , financially supported by the aviation-loving multimillionaire Harold Frederick Pitcairn, who also gave the production its name under the abbreviation PCA . The 300 hp machines made flights to Mexico and Cuba.
On July 29, 1926, the C.6D took off for the first flight, only to carry out the first flight with two people one day later; Juan de la Cierva himself was the passenger. Other nations also showed interest in this device at this time: in the same year on September 5, 1926, Ernst Udet flew the Cierva C.6D in Berlin at the Tempelhof airfield. C.6D built in England is considered the world's first two-seater autogiro. Due to the higher payload, a more powerful engine than in the previous models, a so-called Clerget engine with 97 kW (132 PS) was installed. Control was only possible from the rear seat.
In 1932, Cierva Autogiro GmbH was founded in Berlin . In the following years up to 1938, the Focke-Wulf company built a total of 43 type C30 gyroplanes under the license of Cierva Autogiro GmbH. This machine became known as the grasshopper . In 1933 the type C.30 began to be delivered to end customers in France, Sweden, Holland, Austria, Australia, Switzerland, Japan and Germany. Just a year later, Cierva founded Lioré & Olivier, a production company in France. At the end of 1936 Juan de la Cierva published the publication "Theory of Stresses on Autogiro Rotor Blades".
He died shortly afterwards, on December 9, 1936, at the age of only 41, in the crash of a KLM Douglas DC-2 liner aircraft , shortly after taking off from Croydon Airport near London.
Awards and honors
International
- Gold medal from the Federación Aeronáutique Internacional.
- Gran Prix Scientifique de l'Air, 1925, de la Société Française de la Navigation Aérienne.
- Miembro de la Société Française de Locomotion Aérienne.
- Honorary member of AIDA, Italy.
- "Fellow" of the Royal Aeronautical Society .
- Socio de honor del Aero Club Brasileño.
- John Scott Award, from the Board of Directors of City Trust, Philadelphia, USA.
- Order of Leopold, Belgium .
- Legion of Honor , France.
- Medalla de Oro de la Wakefield, concedida por la Royal Aeronautical Society (1934).
- Grand Prix Academie des Sports (Foundation "Henry Deutsch de la Meurthe", 1928).
- Honorary member of the Aero clubs of Greater Belgium, Germany, France and Belgium.
- Prix Latham, 1928, del Aero Club de Francia, por el viaje en Autogiro Londres-París (primera travesía del Canal de la Mancha).
Spain
- Premio de la Fundación Duque de Alba.
- Banda de la Orden de la República.
- Medalla de Oro del Trabajo, 1930.
- 1936, Premio de la Fundación Deu y Mata.
- Miembro de honor de la Asociación de Ingenieros Aeronáuticos.
- Medallas de Oro de las ciudades de Madrid y Murcia.
Posthumously
- 1937, a título póstumo, Medalla de Oro de la Royal Aeronautical Society, Inglaterra.
- From 1937 to March 1939, the Republican Post in Spain issued a two-peseta postage stamp showing Juan de la Cierva's autogiro high above the capital, and from January 14, 1939 the Franco government issued a series of seven postage stamps for the (mistakenly) 4th anniversary of death.
- Cierva Cove , a bay on the west coast of the Antarctic Peninsula , has been named in his honor since 1960 . Indirectly, he is also the namesake for the Cierva Point , a headland in the immediate vicinity
- A monument was erected in Murcia in honor of Juan de la Cierva.
- In 2003 a metro station in Madrid that bears his name went into operation.
Exhibits
Some aircraft can still be viewed today. A Cierva C19 Mk IV Autogiro from 1932 can be found in the Museo de Aeronautica y Astronautica in Madrid. The Musée de l'Air et de l'Espace at Le Bourget Airport near Paris exhibits a Cierva C 8 Autogiro and a Cierva CB 11 with approval G-EBYY. Further exhibits can be found in the Royal Air Force Museum in Hendon.
Photo gallery
Documents
Patent excerpt page 1
Drawing from patent specification with 10 centimos fee stamp
literature
- T. Martín-Barbadillo: El Autogiro, ayer, hoy y mañana . «Avión», Madrid 1935 enero 1956 y enero-april 1963
- Engelbert Zaschka : rotary wing aircraft. Gyroscopes and helicopters. CJE Volckmann Nachf. E. Wette, Berlin-Charlottenburg 1936, OCLC 20483709
- E. García Albors: Juan de la Cierva y su autogiro . Aeronática, Aviación, Aviones, Helicópteros. Bibl., Madrid 1965
- Peter W. Brooks: Cierva Autogiros . Smithsonian Institution Press, Washington 1988
- José Warleta: Autogiro. Juan de la Cierva y su obra . Colección Cultura y Ciencia, Instituto de España
- Bruce H. Charnov: From Autogiro to Gyroplane , Praeger, Westport Connecticut 2003, ISBN 1-56720-503-8
See also
Web links
- Royal Air Force Museum
- Image of the Cierva CB 11 with approval G-EBYY in Le Bourget
- Article on gyroplanes from June 1, 2006
- Metro station in Madrid - La estación de Juan de la Cierva
- The first constant flight of a helicopter on September 18, 1928 (see Allgemeine Automobil-Zeitung of October 15, 1928 - Austrian National Library)
Individual evidence
- ↑ a b Bruce H. Charnov: From Autogiro to Gyroplane , ISBN 1-56720-503-8 , p. 13
- ↑ a b Bruce H. Charnov: From Autogiro to Gyroplane , ISBN 1-56720-503-8 , p. 6
- ↑ Bruce H. Charnov: From Autogiro to Gyroplane , ISBN 1-56720-503-8 , p. 20
- ↑ a b c d e Bruce H. Charnov: From Autogiro to Gyroplane , ISBN 1-56720-503-8 , p. 17
- ↑ Text of the British patent 165.748 by June 30, 1921
- ↑ Text of U.S. Patent 1,590,497, March 31, 1923
- ↑ Aircraft accident in Croydon on December 9, 1936 , accessed on June 20, 2019
- ↑ Bruce H. Charnov: From Autogiro to Gyroplane , ISBN 1-56720-503-8 , p. 113
- ↑ Bruce H. Charnov: From Autogiro to Gyroplane , ISBN 1-56720-503-8 , p. 35
- ↑ Bruce H. Charnov: From Autogiro to Gyroplane , ISBN 1-56720-503-8 , p. 91
| personal data | |
|---|---|
| SURNAME | Cierva, Juan de la |
| ALTERNATIVE NAMES | Cierva y Codorníu, Juan de la |
| BRIEF DESCRIPTION | Spanish aviation pioneer |
| DATE OF BIRTH | September 21, 1895 |
| PLACE OF BIRTH | Murcia , Spain |
| DATE OF DEATH | December 9, 1936 |
| Place of death | near London |