The Focke-Achgelis Fa 269 was a

tiltrotor A tiltrotor is an aircraft which generates lift and propulsion by way of one or more powered rotors (sometimes called ''proprotors'') mounted on rotating shafts or nacelles usually at the ends of a fixed wing. Almost all tiltrotors use a trans ...

VTOL A vertical take-off and landing (VTOL) aircraft is one that can take off and land vertically without relying on a runway. This classification can include a variety of types of aircraft including helicopters as well as thrust-vectoring fixed-wi ...

aircraft project designed by Henrich Focke.

Development

Conceived as a single-seat fighter, the Fa 269 project resulted from a design study order issued by the Reich Air Ministry to Focke-Achgelis in 1941. The order called for a local defence fighter which would combine the VTOL capabilities of a helicopter with the speed and economy of a conventional fixed-wing aircraft. A large amount of

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 ...

testing was undertaken, along with work on gearboxes, drives and power-pivoting mechanisms, and a full-scale mock-up of the aircraft was built to demonstrate the VTOL concept, but much of this was destroyed by Allied bombing raids and all work was shelved in 1944, when Focke-Achgelis estimated that there was little likelihood of a practical prototype being available before 1947.

Design

A mid-wing monoplane, the Fa 269 was to have been powered by a single

BMW 801 The BMW 801 was a powerful German air-cooled 14-cylinder- radial aircraft engine built by BMW and used in a number of German Luftwaffe aircraft of World War II. Production versions of the twin-row engine generated between 1,560 and 2,000 P ...

air-cooled

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 ...

buried in the fuselage behind the cockpit, which was to have driven transverse drive shafts in the leading edges of the fixed wing, the shafts turning three-bladed rotors via synchronised gearboxes. The

plane of rotation In geometry, a plane of rotation is an abstract object used to describe or visualize rotations in space. In three dimensions it is an alternative to the axis of rotation, but unlike the axis of rotation it can be used in other dimensions, such as ...

of the rotors would have been capable of being swivelled through 80° using angled extension shafts. It was proposed that the Fa 269 would adopt a high angle of attack when at rest using extremely long undercarriage units. For vertical take-off, the rotors would be lowered till their plane of rotation was parallel with the ground. For translation to conventional flight following take-off, the extension shafts were to pivot to the rear, the rotors then behaving as pusher propellers.

Specifications (Fa 269)

References

* * {{RLM aircraft designations Abandoned military aircraft projects of Germany Focke-Achgelis aircraft 1940s German experimental aircraft Research and development in Nazi Germany Tiltrotor aircraft Mid-engined aircraft Single-engined twin-prop pusher aircraft