Bundesarchiv Bild 102-09500, Windmühlen-Aeroplan Cleaned'n'Cropped

The Cierva C.6 was the sixth

autogyro An autogyro (from Greek and , "self-turning"), also known as a ''gyroplane'', is a type of rotorcraft that uses an unpowered rotor in free autorotation to develop lift. Forward thrust is provided independently, by an engine-driven propeller. Whi ...

Juan de la Cierva Juan de la Cierva y Codorníu, 1st Count of la Cierva (; 21 September 1895 in Murcia, Spain – 9 December 1936 in Croydon, United Kingdom) was a Spanish civil engineer, pilot and a self taught aeronautical engineer. His most famous accomplis ...

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

Cierva The Cierva Autogiro Company was a British firm established in 1926 to develop the autogyro. The company was set up to further the designs of Juan de la Cierva, a Spanish engineer and pilot, with the financial backing of James George Weir, a Scotti ...

, the

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

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 programming. A prototype is generally used to ...

s. Therefore, in 1923, he turned to the Cuatro Vientos Aerodynamics Laboratory chief, Commander Emilio Herrera, who succeeded in persuading General Francisco Echagüe, 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 Greek and , "self-turning"), also known as a ''gyroplane'', is a type of rotorcraft that uses an unpowered rotor in free autorotation to develop lift. Forward thrust is provided independently, by an engine-driven propeller. ...

. After several

wind tunnel Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft ...

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

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

frame. This machine, piloted by Captain Joaquín Loriga Taboada, made three flights, all of them in March 1924. One of those flights, the eight-minute trip from

Cuatro Vientos Cuatro Vientos is a ward (''barrio'') 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 airport. External ...

airfield to

Getafe Getafe () is a 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 centre, within a flat ar ...

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 may refer to: Science and technology Engineering * Rotor (electric), the non-stationary part of an alternator or electric motor, operating with a stationary element so called the stator *Helicopter rotor, the rotary wing(s) of a rotorcraft ...

. Only the front propeller was powered, so this aircraft could not hover, and could lose control at low speed. The vertical axis rotor spun freely; the faster the autogyro flew, the faster the rotor would spin and the greater lift it produced. A replica of the Cierva C.6 was built to be shown in

Murcia Murcia (, , ) is a city in south-eastern Spain, the capital and most populous city of the autonomous community of the Region of Murcia, and the seventh largest city in the country. It has a population of 460,349 inhabitants in 2021 (about one ...

pavilion in

Seville Seville (; es, Sevilla, ) is the capital and largest city of the Spanish autonomous community of Andalusia and the province of Seville. It is situated on the lower reaches of the River Guadalquivir, in the southwest of the Iberian Penins ...

Expo '92

World's Fair A world's fair, also known as a universal exhibition or an expo, is a large international exhibition designed to showcase the achievements of nations. These exhibitions vary in character and are held in different parts of the world at a specif ...

. That replica can be now be seen in

Museo del Aire (Spain) Museum of Aeronautics and Astronautics ( es, Museo de Aeronáutica y Astronáutica), also known as Air Museum (), is an aviation museum located near of Madrid, is situated at Cuatro Vientos Air Base, Spain. The objective of the museum is to ac ...

, Cuatro Vientos,

Madrid Madrid ( , ) is the capital and most populous city of Spain. The city has almost 3.4 million inhabitants and a metropolitan area population of approximately 6.7 million. It is the second-largest city in the European Union (EU), and ...

, 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 was a nine-cylinder 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 Clerget 9Bf was ...

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