Consolidated Vultee XP-81
From Wikipedia, the free encyclopedia
| Consolidated Vultee XP-81 | |
|---|---|
 |
|
| Type | Escort fighter |
| Manufacturer | Consolidated Vultee Aircraft Corporation |
| Maiden flight | 11 February 1945 |
| Status | Cancelled |
| Primary user | United States Air Force |
| Number built | 2 |
| Unit cost | US$4.6 million for the program[1] |
The Consolidated Vultee XP-81 was a development of the Consolidated Vultee Aircraft Corporation to build a single seat, long range escort fighter that combined use of both a turbojet and a turboprop engines. Although promising, the lack of a suitable engine combined with the end of World War II doomed the project.
Contents |
[edit] Design and development
Two prototype aircraft were ordered on 11 February 1944 that were designated XP-81. The engine selection was an attempt to couple the high-speed capability of the jet engine with the endurance offered by the propeller engine. The XP-81 was designed to use the General Electric TG-100 turboprop engine (later designated XT-31) in the nose driving a four-bladed propeller and an Allison J33 turbojet in the rear fuselage. The turboprop would be used for normal flight and cruising and the turbojet added for high-speed flight.
[edit] Testing
The first XP-81 (serial 44-91000) was completed in January 1945 but because of developmental problems the turboprop engine was not ready for installation. A decision was then made to mount a complete V-1650-7 Merlin engine package from a P-51D aircraft in place of the turboprop for initial flight tests. This was done in a week and the Merlin-powered XP-81 was sent to the Muroc airbase where it flew for the first time on 11 February 1945. During ten flight test hours, the XP-81 displayed good handling characteristics except for inadequate directional stability due to the longer forward portion of the fuselage (this was rectified by enlarging the vertical tail.[2]
While 13 YP-81 pre-production aircraft had been ordered, the capture of Guam and Saipan removed the need for long-range, high-speed escort fighters and, then, just before VJ Day the contract was cancelled, after 85% of the engineering was completed. The YP-81 was to be essentially the same as the prototype but with a lighter, more powerful TG-110 turboprop engine, the wing moved aft 10 inches (0.25 m), and armament of either six .50 cal (12.7 mm) machine guns or six 20 mm cannon.
After the XP-81 was returned to Vultee Field, the TG-100 turboprop was installed and flight testing resumed. However, the turboprop engine was not able to produce its designed power; producing only the same output as the Merlin (1,490 hp or 1112 kW) with the resultant performance limited to that of the Merlin-powered configuration.
[edit] Cancellation
With the termination of hostilities, the two prototypes continued to be tested until 1947 when they were both ignominiously consigned to a bombing range as photography targets.[3]
[edit] Specifications (XP-81)
Note: Performance is estimated with 'full powered' TG-100 General characteristics
- Crew: 1
- Length: 44 ft 10 in (13.67 m)
- Wingspan: 50 ft 6 in (15.39 m)
- Height: 14 ft 0 in (4.27 m)
- Wing area: 425 ft² (39.5 m²)
- Empty weight: 12,755 lb (5,786 kg)
- Loaded weight: 19,500 lb (8,850 kg)
- Max takeoff weight: 24,650 lb (11,180 kg)
- Powerplant:
- 1× Allison J33-GE-5 turbojet, 3,750 lbf (16.7 kN)
- 1× General Electric XT31-GE-1 turboprop, 2,300 hp (1,700 kW)
Performance
- Maximum speed: 507 mph (440 knots, 811 km/h)
- Range: 2,500 mi (2,200 nm, 4,000 km)
- Service ceiling 35,500 ft (10,800 m)
- Rate of climb: 5,300 ft/min (26 m/s)
- Wing loading: 106 lb/ft² (518 kg/m²)
Projected armament
[edit] References
[edit] Notes
[edit] Bibliography
- Ginter, Steve. Consolidated Vultee XP-81 (Air Force Legends Number 214). Simi Valley, California: Ginter Books, 2007. ISBN 0-942612-87-6.
- Green, William. War Planes of the Second World War, Volume Four: Fighters. London: Macdonald & Co.(Publishers) Ltd.,1961. ISBN 0-356-01448-7.
- Green, William and Swanborough, Gordon. WW2 Aircraft Fact Files: US Army Air Force Fighters, Part 2. London: Macdonald and Jane's Publishers Ltd., 1978. ISBN 0-354-01072-7.
- Knaack, Marcelle Size. Encyclopedia of US Air Force Aircraft and Missile Systems: Volume 1 Post-World War II Fighters 1945-1973. Washington, DC: Office of Air Force History, 1978. ISBN 0-912799-59-5.
- Winchester, Jim. The World's Worst Aircraft: From Pioneering Failures to Multimillion Dollar Disasters. London: Amber Books Ltd., 2005. ISBN 1-904687-34-2.
[edit] External links
[edit] See also
Related development
Comparable aircraft
Related lists
|
||||||||||||||
|
||||||||
