The Focke-Wulf Fw 61 is often considered the first practical, functional

helicopter A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes ...

, first flown in 1936. It was also known as the Fa 61, as Focke began a new company—

Focke-Achgelis Focke-Achgelis & Co. G.m.b.H. was a German helicopter company founded in 1937 by Henrich Focke and Gerd Achgelis. History Henrich Focke was ousted in 1936 from the Focke-Wulf company, which he had cofounded in 1924, due to shareholder pressure ...

—in 1937.

Design and development

DBP 1979 1008 Jugendmarke Focke-Wulf FW 61 1936

Professor

Henrich Focke Henrich Focke (8 October 1890 – 25 February 1979) was a German aviation pioneer from Bremen and also a co-founder of the Focke-Wulf company. He is best known as the inventor of the Fw 61, the first successful German helicopter. Biography ...

, through his development of the Fw 186, and through the efforts of producing the C.19 and C.30 autogyros under licence, came to the conclusion that the limitations of autogyros could be eliminated only by an aircraft with a powered rotor, the helicopter. He and engineer

Gerd Achgelis Gerd Achgelis (16 July 1908 – 18 May 1991) was a German aviator, test pilot, and pioneer in the development of helicopters. Biography Achgelis was born in Golzwarden in Oldenburg, and after an apprenticeship as an electrician, began working ...

started the design for this helicopter in 1932. A free-flying model, built in 1934 and propelled by a small two-stroke engine, brought the promise of success. Today, the model can be seen in the

Deutsches Museum The Deutsches Museum (''German Museum'', officially (English: ''German Museum of Masterpieces of Science and Technology'')) in Munich, Germany, is the world's largest museum of science and technology, with about 28,000 exhibited objects from ...

Munich Munich ( ; german: München ; bar, Minga ) is the capital and most populous city of the States of Germany, German state of Bavaria. With a population of 1,558,395 inhabitants as of 31 July 2020, it is the List of cities in Germany by popu ...

. On 9 February 1935, Focke received an order for the building of a

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 prototyp ...

, which was designated the Fw 61; Focke referred to it as the F 61. Roluf Lucht of the technical office of the RLM extended the order for a second aircraft on 19 December 1935. The

airframe The mechanical structure of an aircraft is known as the airframe. This structure is typically considered to include the fuselage, undercarriage, empennage and wings, and excludes the propulsion system. Airframe design is a field of aerospa ...

was based on that of a well-tried training aircraft, the

Focke-Wulf Fw 44 The Focke-Wulf Fw 44 ''Stieglitz'' ("Goldfinch") is a 1930s German two-seat biplane. An early design by Kurt Tank, it was produced by the Focke-Wulf company as a pilot training and sports flying aircraft. It was also eventually built under lice ...

''Stieglitz''. Using rotor technology licensed from the

Cierva Autogiro Company 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 ...

, a single

radial engine The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders "radiate" outward from a central crankcase like the spokes of a wheel. It resembles a stylized star when viewed from the front, and is ca ...

drove twin rotors, set on tubular steel outriggers to the left and right of the

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

. Each main rotor consisted of three articulated and tapered blades, driven by the engine through gears and shafts. Longitudinal and directional control was achieved using cyclic pitch and asymmetric rotor lift. The counter-rotation of the two rotors solved the problem of

torque In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of th ...

-reaction as also shown by

Louis Bréguet Louis Charles Breguet (2 January 1880 in Paris – 4 May 1955 in Saint-Germain-en-Laye, Île-de-France) was a French aircraft designer and builder, one of the early aviation pioneers. Biography Louis Charles Breguet was the grandson of Lo ...

. The small horizontal-axis propeller directly driven by the engine was purely to provide the necessary airflow to cool the engine during low speed or hovering flight and provided negligible forward thrust. Only two aircraft were produced. The first prototype, the V 1 D-EBVU, had its first free flight on 26 June 1936 with

Ewald Rohlfs Ewald Rohlfs (1911 Bremen, Germany - 1984) was a test pilot. In June 1936 Rohlfs made the first flight of a helicopter A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This a ...

at the controls. By early 1937, the second prototype, V 2 D-EKRA, was completed and flown for its first flight. On 10 May 1937, it accomplished its first

autorotation Autorotation is a state of flight in which the main rotor system of a helicopter or other rotary-wing aircraft turns by the action of air moving up through the rotor, as with an autogyro, rather than engine power driving the rotor. Bensen, Igor ...

landing with the engine turned off. Focke-Achgelis began work on a two-seat sports version of the Fw 61, the ''Fa 224'', which would have used an Argus As 10C engine and had greater performance. However, the Fa 224 never left the drawing board at the outbreak of World War II.

Operational history

In February 1938, the Fw 61 was demonstrated by

Hanna Reitsch Hanna Reitsch (29 March 1912 – 24 August 1979) was a German aviator and test pilot. Along with Melitta von Stauffenberg, she flight tested many of Germany's new aircraft during World War II and received many honors. Reitsch was amon ...

indoors at the ''

Deutschlandhalle Deutschlandhalle was an arena located in the Westend neighbourhood of Berlin, Germany. It was inaugurated on 29 November 1935 by Adolf Hitler. The building was granted landmark status in 1995, but was demolished on 3 December 2011. History Buil ...

'' sports stadium in Berlin, Germany.Ruffin 2005, p. 19. It subsequently set several records for

altitude Altitude or height (also sometimes known as depth) is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context ...

speed In everyday use and in kinematics, the speed (commonly referred to as ''v'') of an object is the magnitude of the change of its position over time or the magnitude of the change of its position per unit of time; it is thus a scalar quanti ...

and flight

duration Duration may refer to: * The amount of time elapsed between two events * Duration (music) – an amount of time or a particular time interval, often cited as one of the fundamental aspects of music * Duration (philosophy) – a theory of time and ...

culminating, in June 1938, with an altitude record of 3,427 m (11,243 ft), breaking the unofficial altitude record of the TsAGI 1-EA single lift-rotor helicopter from the Soviet Union set in August 1932, and a straight line flight record of 230 km (143 mi). Neither of these machines appear to have survived

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

, although a replica is on display at the Hubschraubermuseum in

Bückeburg Bückeburg (Northern Low Saxon: ''Bückeborg'') is a town in Lower Saxony, Germany, on the border with North Rhine Westphalia. It is located in the district of Schaumburg close to the northern slopes of the Weserbergland ridge. Population: 21,0 ...

, Germany.

Specifications (Fw 61)

References

Notes

Bibliography

* Coates, Steve and Jean-Christophe Carbonel. ''Helicopters of the Third Reich''. Crowborough, UK: Classic Publications Ltd., 2002. . * Green, William. Aircraft of the Third Reich, Vol.1''. London: Aerospace Publishing Limited, (First ed.) 2010. . * Nowarra, Heinz J. ''German Helicopters, 1928–1945''. Atglen, Pennsylvania: Schiffer Publishing, 1990. . * Ruffin, Steven A. Aviation's Most Wanted: The Top 10 book of Winged Wonders, Lucky Landings and Other Aerial Oddities. Washington D.C.: Potomac Books, 2005. . * Smith, J. Richard. ''Focke-Wulf, an Aircraft Album''. London: Ian Allan Ltd., 1973. . * Smith, J. Richard and Anthony Kay. ''German Aircraft of the Second World War''. London: Putnam & Company Ltd., 1972 (3rd edition 1978). . * Witkowski, Ryszard. ''Rotorcraft of the Third Reich''. Redbourn, UK: Mushroom Model Publications, 2007. .

External links

French & German Helicopter Pioneers (Fa 61)

Focke Wulf Fw 61 luftwaffe
at YouTube
Vertical Rewind: Spoils of WarArchive
{{Use dmy dates, date=May 2019 1930s German experimental aircraft Military helicopters World War II helicopters of Germany Fw 061 1930s German helicopters Transverse rotor helicopters Single-engined piston helicopters Aircraft first flown in 1936