The Cierva C.6 was the sixth

autogyro An autogyro (from Greek and , "self-turning"), gyroscope, gyrocopter or gyroplane, is a class of rotorcraft that uses an unpowered rotor in free autorotation to develop lift. A gyroplane "means a rotorcraft whose rotors are not engine-d ...

Juan de la Cierva Juan de la Cierva y Codorníu, 1st Count of la Cierva (; 21 September 1895 – 9 December 1936), was a Spanish civil engineer, pilot and a self-taught aeronautical engineer. His most famous accomplishment was the invention in 1920 of a rotorcr ...

, and the first one to travel a "major" distance. Cierva, the

engineer Engineers, as practitioners of engineering, are professionals who Invention, invent, design, build, maintain and test machines, complex systems, structures, gadgets and materials. They aim to fulfill functional objectives and requirements while ...

responsible for the invention of the

, had spent all his funds on the research and creation of his first five

prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototype ...

s. Therefore, in 1923, he turned to the Cuatro Vientos Aerodynamics Laboratory chief, Commander Emilio Herrera, who succeeded in persuading General

Francisco Echagüe Francisco is the Spanish and Portuguese form of the masculine given name ''Franciscus''. Meaning of the name Francisco In Spanish, people with the name Francisco are sometimes nicknamed " Paco". San Francisco de Asís was known as ''Pater Comm ...

, the director of the Military Aviation Aeronautics Department, to take over the second stage in the research and development of Cierva's

autogyros An autogyro (from Ancient Greek, Greek and , "self-turning"), gyroscope, gyrocopter or gyroplane, is a class of rotorcraft that uses an unpowered Helicopter rotor, rotor in free autorotation to develop lift (force), lift. A gyroplane "means a ...

. After several

wind tunnel A wind tunnel is "an apparatus for producing a controlled stream of air for conducting aerodynamic experiments". The experiment is conducted in the test section of the wind tunnel and a complete tunnel configuration includes air ducting to and f ...

tests, Military Aviation built a Cierva C.6 autogyro in an

Avro 504 The Avro 504 is a single-engine biplane bomber made by the Avro, Avro aircraft company and under licence by others. Production during World War I totalled 8,970 and continued for almost 20 years, making it the most-produced aircraft of any kind ...

frame. This machine, piloted by Captain

Joaquín Loriga Joaquín Loriga Taboada (23 September 1895 in Lalín – 18 July 1927 in Cuatro Vientos Airport) was a Galician aviation pioneer. In 1926 as a captain, together with two pilots and three mechanical engineers, completed the first long-distance flig ...

Taboada, made three flights, all of them in March 1924. One of those flights, the eight-minute trip from

Cuatro Vientos Cuatro Vientos is an administrative neighborhood () of Madrid belonging to the district of Latina. Geography Cuatro Vientos is situated in the south-western area of central Madrid, close to the motorways A5 and M40 and to the homonymous airpor ...

airfield to

Getafe Getafe () is a municipalities in Spain, municipality and a city in Spain belonging to the Community of Madrid. , it has a population of 180,747, the region's sixth most populated municipality. Getafe is located 13 km south of Madrid's city c ...

airfield (), was considered a giant step for Cierva's autogyros. The Cierva C.6 prototype was fitted with ailerons mounted on two small wings, also with elevators and a rudder. This complete three-axis control scheme was needed because the pilot had only limited control over the

rotor ROTOR was an elaborate air defence radar system built by the British Government in the early 1950s to counter possible attack by Soviet bombers. To get it operational as quickly as possible, it was initially made up primarily of WWII-era syst ...

. The engine powered the propeller at the front while the rotor on top was unpowered, driven instead by air flowing upward through the inner region of the rotor disc. This meant that the aircraft, like all autogyros, could not hover. But so long as there was sufficient airflow to turn the rotor the aircraft could safely descend, even at low airspeeds where a conventional airplane would stall and possibly crash. A replica of the Cierva C.6 was built to be shown in

Murcia Murcia ( , , ) is a city in south-eastern Spain, the Capital (political), capital and most populous city of the autonomous community of the Region of Murcia, and the Ranked lists of Spanish municipalities#By population, seventh largest city i ...

pavilion in

Seville Seville ( ; , ) is the capital and largest city of the Spain, Spanish autonomous communities of Spain, autonomous community of Andalusia and the province of Seville. It is situated on the lower reaches of the Guadalquivir, River Guadalquivir, ...

Expo '92

World's Fair A world's fair, also known as a universal exhibition, is a large global exhibition designed to showcase the achievements of nations. These exhibitions vary in character and are held in different parts of the world at a specific site for a perio ...

. That replica can be now be seen in Museo del Aire (Spain), Cuatro Vientos,

Madrid Madrid ( ; ) is the capital and List of largest cities in Spain, most populous municipality of Spain. It has almost 3.5 million inhabitants and a Madrid metropolitan area, metropolitan area population of approximately 7 million. It i ...

, Spain.

Variants

;Cierva C.6: Prototype. ;Cierva C.6A: Powered by an Le Rhône 9Ja rotary piston engine. ;Cierva C.6B: ;Cierva C.6C: Powered by a

Clerget 9B The Clerget 9B is a nine-cylinder rotary engine, rotary aircraft engine of the World War I era designed by Pierre Clerget. Manufactured in both France and Great Britain (Gwynnes Limited), it was used on such aircraft as the Sopwith Camel. The Cler ...

rotary piston engine. Built in the United Kingdom as Avro Type 574. ;Cierva C.6D: Powered by a Clerget 9B rotary piston engine. Built in the United Kingdom as the Avro Type 575.

Specifications (C.6)

References

* Original pictures and data of this article were taken from "Museo del Aire", Cuatro Vientos, Madrid, Spain
Cierva c.6 / Avro 574

Variants

Specifications (C.6)

References

See also