A tiltwing

aircraft An aircraft ( aircraft) is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or the Lift (force), dynamic lift of an airfoil, or, i ...

features a wing that is horizontal for conventional forward flight and rotates up for vertical takeoff and landing. It is similar to the

tiltrotor A tiltrotor is an aircraft that generates lift (force), lift and thrust, propulsion by way of one or more powered Helicopter rotor, rotors (sometimes called ''proprotors'') mounted on rotating shaft (mechanical engineering), shafts or nacelles ...

design where only the

propeller A propeller (often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working flu ...

and engine rotate. Tiltwing aircraft are typically fully capable of

VTOL A vertical take-off and landing (VTOL) aircraft is one that can takeoff and landing, 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- ...

operations.Markman, Steve and Bill Holder. "Tilt-Wing VTOL Systems". ''Straight Up: A History of Vertical Flight''. Schiffer Publishing, 2000. . VTOL DiscLoad-LiftEfficiency

The tiltwing design offers certain advantages in vertical flight relative to a tiltrotor. Because the slipstream from the rotor strikes the wing on its smallest dimension, the tiltwing is able to apply more of its engine power to lifting the aircraft. For comparison, the

V-22 Osprey The Bell Boeing V-22 Osprey is an American multi-use, tiltrotor military transport aircraft, military transport and cargo aircraft with both vertical takeoff and landing (VTOL) and short takeoff and landing (STOL) capabilities. It is designed ...

tiltrotor loses about 10% of its thrust to interference from the wings. Another advantage of tiltwing aircraft is the ease of transition between VTOL and horizontal flight modes. A tiltrotor must first fly forwards like a helicopter, building airspeed until wing lift is sufficient to allow the nacelles to begin tilting down. As a note, the MV-22 Osprey's stall speed in airplane mode is . Conversely, a tiltwing aircraft can begin the transition from helicopter to airplane at zero forward airspeed. Because of this, the Canadair CL-84 Dynavert was able to take off vertically, then accelerate from zero airspeed to in 8 seconds. However, the fixed wing of a tiltrotor aircraft offers a superior

angle of attack In fluid dynamics, angle of attack (AOA, α, or \alpha) is the angle between a Airfoil#Airfoil terminology, reference line on a body (often the chord (aircraft), chord line of an airfoil) and the vector (geometry), vector representing the relat ...

—thus more lift and a shorter takeoff roll—when performing

STOL A short takeoff and landing (STOL) aircraft is a fixed-wing aircraft that can takeoff/land on short runways. Many STOL-designed aircraft can operate on airstrips with harsh conditions (such as high altitude or ice). STOL aircraft, including tho ...

STOVL A short take-off and vertical landing aircraft (STOVL aircraft) is a fixed-wing aircraft that is able to take off from a short runway (or take off vertically if it does not have a heavy payload) and land vertically (i.e. with no runway). The ...

operations. The main drawbacks of tiltwing aircraft are susceptibility to wind gusts in VTOL mode and lower hover efficiency. The wing tilted vertically represents a large surface area for crosswinds to push against. Tiltrotors generally have better hover efficiency than tiltwings, but less than helicopters. This is due to the difference in rotor disk loading. As of 2014,

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

is testing a diesel-electric hybrid 10-foot 10-rotor tiltwing called the GL-10 Greased Lightning, with most propellers folding during horizontal flight.Warwick, Graham. "Distributed power" ''

Aviation Week & Space Technology ''Aviation Week & Space Technology'', often abbreviated ''Aviation Week'' or ''AW&ST'', is the flagship magazine of the Aviation Week Network, a division of Informa. The weekly magazine is available in print and online, reporting on the aeros ...

'' page 31, 25 August 2014. Accessed: 26 August 2014.

List of tiltwing aircraft

Tiltwing designs with rocket, jet, or propeller propulsion * Weserflug P.1003 (1938) * Vertol VZ-2 (1957) * Hiller X-18 (1959) *

Kaman K-16B The Kaman K-16B is an experimental VTOL, vertical-takeoff-and-landing aircraft that was constructed by Kaman Aircraft for the United States Navy in 1959 to evaluate the tiltwing concept. Converted from a Grumman Goose amphibian, the K-16B underwe ...

(1959) *

LTV XC-142 The Ling-Temco-Vought (LTV) XC-142 is a tiltwing experimental aircraft designed to investigate the operational suitability of vertical/short takeoff and landing (V/STOL) transports. An XC-142A first flew conventionally on 29 September 1964, an ...

(1964) * Canadair CL-84 Dynavert (1965) * NASA GL-10 Greased Lightning (2014) * Airbus A³ Vahana (2018)

References

{{Aircraft types (by method of thrust and lift) Aircraft configurations

List of tiltwing aircraft

See also

References