Bell X-14

X-14
275px
Bell Type 68 VTOL
Type	Experimental VTOL
Manufacturer	Bell Aircraft
Maiden flight	19 February 1957
Retired	29 May 1981
Status	Out of service
Primary users	NASA United States Air Force
Number built	1

The Bell X-14 (Bell Type 68) was an experimental VTOL aircraft flown in the United States in the 1950s. The main objective of the project was to demonstrate horizontal and vertical takeoff, hover, transition to forward flight, and vertical landing.

Development

Bell constructed the X-14 as an open-cockpit, all-metal monoplane. It was powered by two Armstrong Siddeley Viper turbojet engines equipped with thrust deflectors sited at the aircraft's centre of gravity. The engines are fixed in position; transition from vertical to horizontal flight is achieved with a system of movable vanes that control the direction of engine thrust. Top speed was 180 miles per hour with a service ceiling of 20,000 feet. The X-14 was designed using existing parts from two Beech aircraft: wings, ailerons, and landing gear of a Bonanza and the tailcone and empennage of a Model 45.

Operational history

The X-14 first flew on 19 February, 1957 as a vertical takeoff, hover, then vertical landing. The first transition from hover to horizontal flight occurred on 24 May, 1958. In 1959, its Viper engines were replaced with General Electric J85s. That year, the aircraft was delivered to the NASA Ames Research Center as the X-14A. It served as a test aircraft with NASA until 1981.

The X-14 project provided a great deal of data on VTOL (Vertical TakeOff and Landing) aircraft. The X-14A also was used by NASA for research on lunar landing maneuvers. The X-14A aircraft flight control system was similar to the one proposed for the Lunar Module; Neil Armstrong once flew it as a lunar-landing trainer.

In 1971, the X-14A was fitted with new J85-GE-19 engines as the X-14B. An onboard computer and digital fly-by-wire control system were also installed to enable emulation of landing characteristics of other VTOL aircraft.

The X-14B was used in this test role until it was damaged beyond repair in a landing accident on 29 May, 1981. At the time, there were plans to develop an X-14C with an enclosed cockpit. There were also plans for an X-14T trainer. None of these further versions got beyond the planning stage.

During all of its years of service, the X-14 was flown by over 25 pilots with no serious incidents or injuries. It was the only open cockpit X-plane.

Aircraft serial numbers

Although there was only one airframe, it kept changing serial numbers with every major upgrade.

• X-14 - USAF 56-4022
• X-14A - NASA 234 (N234NA).
• X-14B - NASA 704 (N704NA).

Post-operational history

The X-14 was rescued from the scrap yard in 1999 and is currently undergoing renovation as part of a private collection in western Indiana. The collection is displayed at the Ropkey Armor Museum.

File:X-14 Indiana (2007).JPG

The X-14 is currently undergoing renovation by a private collector in western Indiana. (photo taken 7/29/07)

Specifications (X-14A)

General characteristics

• Crew: 1
• Length: 25 ft 0 in (7.62 m)
• Wingspan: 34 ft 10 in (10.36 m)
• Height: 8 ft 0 in (2.40 m)
• Loaded weight: 3,100 lb (1,406 kg)
• Max takeoff weight: 4,269 lb (1,936 kg)
• Powerplant: 2× Armstrong Siddeley Viper 8 Turbojet, 1,750 lbf (7.8 kN) each

Performance

• Maximum speed: 172 mph (277 km/h)
• Range: 300 miles (482 km)
• Service ceiling: 20,000 ft (6,096 m)
• Thrust/weight: 1:0.9

See also

• List of experimental aircraft

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Bell X-14".