Boeing X-50 Dragonfly

Last updated
X-50
Boeing X-50A.jpg
RoleExperimental gyrodyne UAV
Manufacturer Boeing
First flight24 November 2003
StatusCancelled
Primary user DARPA
Number built2

The Boeing X-50A Dragonfly, formerly known as the Canard Rotor/Wing Demonstrator, was a VTOL rotor wing experimental unmanned aerial vehicle that was developed by Boeing and DARPA to demonstrate the principle that a helicopter's rotor could be stopped in flight and act as a fixed wing, enabling it to transition between fixed-wing and rotary-wing flight.

Contents

The X-50A built upon the work of the Sikorsky S-72 X-Wing program of the 1980s by designing the vehicle as a multi-mode aircraft from the ground up. The X-50A was one of two projects funded by DARPA in its "Heliplane" program. [1] [2]

Neither of the two prototype aircraft ever successfully transitioned to full forward flight. DARPA withdrew funding for the X-50 program in late 2006 due to inherent design flaws. [1]

Development

Boeing initially proposed using the CRW configuration to fill a requirement for a VTOL aircraft suitable for escorting the V-22 tiltrotor.

The X-50A was a joint program between Boeing and DARPA, with each paying for half the development costs. The X-50A was powered by a single conventional turbofan engine. For rotary-wing mode, the engine's exhaust was diverted to nozzles in the tips of the rotor blades. When the aircraft transitioned to full forward flight, the engine exhaust was directed through a nozzle at the rear of the aircraft and the rotor was locked into a fixed position and functioned as a conventional wing. [1] Two proof-of-concept aircraft were built as part of the program. The X-50A's maiden flight took place on 24 November 2003.

Design

The X-50 had a "canard" foreplane as well as a conventional tailplane, allowing both to contribute lift during forward flight and to offload the main rotor wing.

For vertical take-off, hovering, low-speed flight, and vertical landing, the main rotor wing was driven by tip jets, by directing the exhaust from a jet engine through thrust nozzles in the rotor tips. Because the rotor is driven directly by jet thrust, there is no need for a tail rotor to control torque as in a conventional helicopter.

For high-speed forward flight, the exhaust is redirected through an ordinary jet nozzle and the rotor wing is stopped and held in a fixed position, as in a conventional airplane.

Operation

Crashes

During the third flight of the prototype X-50A, on 23 March 2004, the vehicle crashed, as a result of cross-coupling in the controls. [1]

A second, improved prototype ("Ship 2") was then built. On its sixth of 11 planned test flights, Ship 2 was completely destroyed in a crash at the Yuma Proving Ground on April 12, 2006. Subsequent investigation revealed that the aircraft's fuselage was subject to an aerodynamic pitching moment of extreme sensitivity. Both airspeed and rotor wake would produce a nose-up pitching motion that was greater than the flight controls could compensate for. [1]

Outcome

Neither aircraft was able to achieve transition to full forward flight mode during the portions of the test flight program that were completed. In September, 2006, DARPA recognized the inherent design flaws and withdrew funding for the program. [1]

Specifications

General characteristics

Performance

See also

Related Research Articles

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-wing aircraft and other hybrid aircraft with powered rotors such as cyclogyros/cyclocopters and gyrodynes.

<span class="mw-page-title-main">Rockwell-MBB X-31</span> Type of aircraft

The Rockwell-Messerschmitt-Bölkow-Blohm X-31 was an experimental jet fighter designed to test fighter thrust vectoring technology.

<span class="mw-page-title-main">Boeing X-32</span> Multirole combat aircraft prototype by Boeing

The Boeing X-32 is a concept demonstrator aircraft that was designed for the Joint Strike Fighter competition. It lost to the Lockheed Martin X-35 demonstrator, which was further developed into the Lockheed Martin F-35 Lightning II.

<span class="mw-page-title-main">Bell XV-15</span> American experimental tiltrotor aircraft

The Bell XV-15 is an American tiltrotor VTOL aircraft. It was the second successful experimental tiltrotor aircraft and the first to demonstrate the concept's high speed performance relative to conventional helicopters.

<span class="mw-page-title-main">Yakovlev Yak-141</span> Soviet VTOL fighter prototype

The Yakovlev Yak-141, also known as the Yak-41, is a Soviet supersonic vertical takeoff/landing (VTOL) fighter aircraft designed by Yakovlev. It was used for testing.

<span class="mw-page-title-main">Yakovlev Yak-36</span> Soviet experimental VSTOL aircraft

The Yakovlev Yak-36, also known as Izdeliye V, is a Soviet technology demonstrator for a VTOL combat aircraft.

<span class="mw-page-title-main">Curtiss-Wright X-19</span> Experimental VTOL tiltrotor quadcopter airplane

The Curtiss-Wright X-19, company designation Model 200, was an American experimental tiltrotor aircraft of the early 1960s. It was noteworthy for being the last aircraft of any kind manufactured by Curtiss-Wright.

<span class="mw-page-title-main">Lockheed XV-4 Hummingbird</span> American experimental VTOL aircraft

The Lockheed XV-4 Hummingbird was a U.S. Army project to demonstrate the feasibility of using VTOL for a surveillance aircraft carrying target-acquisition and sensory equipment. It was designed and built by the Lockheed Corporation in the 1960s, one of many attempts to produce a V/STOL vertical take off/landing jet. Both prototype aircraft were destroyed in accidents.

<span class="mw-page-title-main">Gyrodyne</span>

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 or jet engines to provide forward thrust during cruising flight. During forward flight the rotor is unpowered and free-spinning, like an autogyro, and lift is provided by a combination of the rotor and conventional wings. The gyrodyne is one of a number of similar concepts which attempt to combine helicopter-like low-speed performance with conventional fixed-wing high-speeds, including tiltrotors and tiltwings.

<span class="mw-page-title-main">Rotorcraft</span> Heavier-than-air aircraft which generates lift over rotating wings

A rotorcraft or rotary-wing aircraft is a heavier-than-air aircraft with rotary wings or rotor blades, which generate lift by rotating around a vertical mast. Several rotor blades mounted on a single mast are referred to as a rotor. The International Civil Aviation Organization (ICAO) defines a rotorcraft as "supported in flight by the reactions of the air on one or more rotors".

A convertiplane is defined by the Fédération Aéronautique Internationale as an aircraft which uses rotor power for vertical takeoff and landing (VTOL) and converts to fixed-wing lift in normal flight. In the US it is further classified as a sub-type of powered lift. In popular usage it sometimes includes any aircraft that converts in flight to change its method of obtaining lift.

<span class="mw-page-title-main">Rockwell XFV-12</span> American VTOL fighter prototype

The Rockwell XFV-12 was a prototype supersonic United States Navy fighter which was built in 1977. The XFV-12 design attempted to combine the Mach 2 speed and AIM-7 Sparrow armament of the McDonnell Douglas F-4 Phantom II in a VTOL fighter for the small Sea Control Ship which was under study at the time. On paper, it looked superior to the subsonic Hawker Siddeley Harrier attack fighter. However it was unable to demonstrate an untethered vertical takeoff and its inability to meet performance requirements terminated the program.

<span class="mw-page-title-main">LTV XC-142</span> Experimental military tilt-wing aircraft

The Ling-Temco-Vought (LTV) XC-142 was a tri-service 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, and on 11 January 1965, it completed its first transitional flight by taking off vertically, changing to forward flight and finally landing vertically. Its service sponsors pulled out of the program one by one, and it eventually ended due to a lack of interest after demonstrating its capabilities successfully.

<span class="mw-page-title-main">Sikorsky S-72</span> US experimental compound helicopter (hybrid helicopter/fixed-wing aircraft)

The Sikorsky S-72 was an experimental compound helicopter developed by helicopter manufacturer Sikorsky Aircraft.

<span class="mw-page-title-main">Short SC.1</span> British experimental VTOL aircraft

The Short SC.1 was the first British fixed-wing vertical take-off and landing (VTOL) jet aircraft. It was developed by Short Brothers. It was powered by an arrangement of five Rolls-Royce RB.108 turbojets, four of which were used for vertical flight and one for conventional horizontal flight. The SC.1 had the distinction of being the first British fixed-wing VTOL aircraft and the first one to transition between vertical and horizontal flight modes; it was also the first VTOL-capable aircraft with a fly-by-wire control system.

<span class="mw-page-title-main">Powered lift</span>

A powered lift aircraft takes off and lands vertically under engine power but uses a fixed wing for horizontal flight. Like helicopters, these aircraft do not need a long runway to take off and land, but they have a speed and performance similar to standard fixed-wing aircraft in combat or other situations.

<span class="mw-page-title-main">VTOL X-Plane</span> American experimental aircraft

The Vertical Take-Off and Landing Experimental Aircraft program is an American research project sponsored by the Defense Advanced Research Projects Agency (DARPA). The goal of the program is to demonstrate a VTOL aircraft design that can take off vertically and efficiently hover, while flying faster than conventional rotorcraft. There have been many previous attempts, most of them unsuccessful.

The period between 1945 and 1979 is sometimes called the post-war era or the period of the post-war political consensus. During this period, aviation was dominated by the arrival of the Jet Age. In civil aviation the jet engine allowed a huge expansion of commercial air travel, while in military aviation it led to the widespread introduction of supersonic aircraft.

<span class="mw-page-title-main">Aurora XV-24 LightningStrike</span> Experimental unmanned aerial vehicle

The Aurora XV-24 LightningStrike is an experimental unmanned aerial vehicle created by Aurora Flight Sciences and partners Rolls-Royce and Honeywell. It was developed for the Vertical Take-Off and Landing Experimental Aircraft program.

References

  1. 1 2 3 4 5 6 McKenna, James T. "One Step Beyond", Rotor & Wing, February, 2007, page 54
  2. "X-50 Dragonfly Canard Rotor/Wing (CRW)". GlobalSecurity.org. Retrieved 2009-03-13.