The Flettner Fl 185 was an experimental

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

gyrodyne A gyrodyne is a type of VTOL aircraft with a helicopter rotor-like system that is driven by its engine for takeoff and landing only, and includes one or more conventional propeller (aircraft), propeller or jet engines to provide forward thrust d ...

developed by

Anton Flettner Anton Flettner (November 1, 1885 – December 29, 1961) was a German aviation engineer and inventor. Born in Eddersheim (today a district of Hattersheim am Main), Flettner made important contributions to airplane, helicopter, vessel, and automo ...

, a machine which could fly both as a

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 ...

and as a

gyroplane 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 ...

Design and development

This aircraft was developed in 1936 with support of the ''

Kriegsmarine The (, ) was the navy of Germany from 1935 to 1945. It superseded the Imperial German Navy of the German Empire (1871–1918) and the inter-war (1919–1935) of the Weimar Republic. The was one of three official branches, along with the a ...

''. It was powered by a BMW-Bramo Sh 14 A radial piston engine with

forced-air A forced-air central heating system is one which uses air as its heat transfer medium. These systems rely on ductwork, vents, and plenums as means of air distribution, separate from the actual heating and air conditioning systems. The return pl ...

cooling, mounted at the nose. The engine drove a 12 m diameter main rotor and two auxiliary propellers mounted on outriggers attached to the fuselage. At take-off or when hovering, the auxiliary propellers worked in opposition to each other and served to cancel the torque of the main rotor, a function handled by a single, variable-pitch tail rotor on contemporary helicopters. In forward flight, however, both propellers worked to provide forward thrust while the rotor autorotated, as in a twin-engined autogyro. The landing gear consisted of a nose-wheel, two smaller stabilising wheels under the outriggers and a tail skid. Only one prototype was constructed.

Design and development

Specifications (Fl 185)

See also

Notes

References

Further reading