Hughes D-2

Infobox Aircraft
name=Hughes D-2
type=Fighter aircraft, Bomber
manufacturer=Hughes Aircraft


caption=Howard Hughes inspecting the port engine c. 1943
designer=Howard Hughes
first flight= 20 June 1943
introduced= Cancelled
retired= 1944
primary user=U.S. Army Air Corps (intended)
number built=1 prototype
related program=Hughes XF-11
program cost=
related program=
developed from=
variants with their own articles=Hughes XF-11The Hughes D-2 was a mysterious American fighter and bomber project begun by Howard Hughes. It never proceeded past the flight testing phase but was considered the inspiration for the later Hughes XF-11. [ Winchester 2005, p. 114.]

Design and development

Howard Hughes began the design of an advanced twin-engine, twin-boom interceptor prior to World War II that was similar to the Lockheed P-38 that won the 1939 United States Army Air Corps design competition. Rather than abandoning the project, he later recounted in the 1947 Senate investigation that he "decided to design and build from the ground up, and with my own money, an entirely new airplane which would be so sensational in its performance that the Army would have to accept it." [ Barton 1982, p. 14-15.]

Most of the airframe of the "DX-2" was made of Duramold plywood, a plastic-bonded plywood molded under heat and high pressure. Initially, the aircraft was to have been a "taildragger," but the landing gear was later changed to a tricycle configuration with the main undercarriage units retracting rearwards into the twin booms and the nosewheel retracing rearwards and rotating 90 degrees to lie flat in the small central fuselage. The powerplants were to have been a pair of experimental Wright Tornado forty-two cylinder, liquid-cooled radial engines. The D-2 was built in secret at the Hughes Culver City, California factory with longtime associate, Glenn Odekirk, providing engineering inputs. Final assembly was done at the Hughes Harper Dry Lake facility in the Mojave Desert. The fighter that emerged from the Hughes experimental shop looked like a scaled-up P-38 Lightning and, on paper, sported similar performance potential.

Difficulties encountered in obtaining the Wright Tornado engines led to the substitution of proven Pratt & Whitney R-2800s. During the development of the fighter, Hughes considered changing the aircraft into a high-speed bomber, resulting in the USAAC issuing two different designations, the XP-73 and XA-37 to the fighter and bomber versions, respectively.

Testing

After it was readied for flight in 1942, Hughes himself took over the flight test program. However, after only a few brief hops, it was clear that high control forces were a problem. When full flight tests were finally conducted in 1943, modifications still had not be made to correct this problem. Hughes reluctantly concluded that the D-2 needed major modifications, including a complete redesign of the wings and a change in aerofoil section. The wing center section, which was continuous through the fuselage nacelle, was to be revised to increase the size of the proposed bomb bay. Following these changes, the aircraft was to be assigned the company designation D-5. After only a few test flights, the sole prototype was destroyed by a freak lightning strike at its desert hangar in November 1944. Barton 1982, p. 15. ]

Aftermath

In 1943, Colonel Elliott Roosevelt, the President's son, had recommended that the D-2 or its successor be ordered as a photo reconnaissance aircraft. Despite his leadership in a military reconnaissance mission, the USAAC did not immediately act on Roosevelt's recommendation, partly due to Hughes' insistence that the D-2 development costs be factored into the proposed contract. Finally in mid-1944, Hughes agreed to develop a high-altitude, high-speed version of the D-2/D-5, known as the XF-11.

pecifications

"McDonnell Douglas Aircraft since 1920: Volume II" [ Francillon 1990, p. 58.]
* Manufacturer: Hughes Aircraft Aircraft
* Crew/Passengers: one pilot, crew of two (in bomber version)
* Powerplant: two convert|2000|hp|abbr=on Pratt and Whitney R-2800-49 (2000 hp)
* Dimensions
** Length: 57 ft 10 in (17.6 m)
** Height: 27 ft 4 in (8.3 m)
** Wing Span: 60 ft (18.29 m)
** Wing area: 616 ft² (57.23 m²)
* Weights
** Loaded: 31,672 lb (14,366 kg)
* Performance(projected)
** Maximum speed 433 mph at 25,000 ft (697 km/h at 7,620 m)
** Cruising speed: 274 mph (441 km/h)
** Rate of Climb: 2,620 ft/min (13 m/sec)
** Service ceiling: 36,000 ft (10,975 m)
** Range: 1,000 miles (1,610 km)
* Armament: None

References

Notes

Bibliography

* Barton, Charles. "Howard Hughes and the 10,000 ft. Split-S." "Air Classics, Vol. 18, no. 8, August 1982".
* Francillon, René J. "McDonnell Douglas Aircraft since 1920: Volume II". Annapolis, Maryland: Naval Institute Press, 1990. ISBN 1-55750-550-0.
* Winchester, Jim. "Hughes XF-11." "Concept Aircraft: Prototypes, X-Planes and Experimental Aircraft". Kent, UK: Grange Books plc., 2005. ISBN 1-84013-309-2.

External links

* [http://library.nevada.edu/hughes/photos/sm_0321_0130.jpgPhoto of the D-2 under construction]
* [http://home.att.net/~jbaugher1/p73.html Hughes XP-73]