Curtiss XP-46

XP-46
Curtiss XP-46 (USAF photo)
Role	Fighter
Manufacturer	Curtiss-Wright Corporation
Designer	Don R. Berlin
First flight	15 February 1941
Primary user	United States Army Air Corps (intended)
Number built	2
Developed from	Curtiss P-40
Developed into	Curtiss XP-53

The Curtiss XP-46 was a 1940s United States prototype fighter aircraft. It was a development of the Curtiss-Wright Corporation in an effort to introduce the best features found in European fighter aircraft in 1939 into a fighter aircraft which could succeed the Curtiss P-40, then in production.

Design and development

A United States Army Air Corps (USAAC) specification based upon a Curtiss proposal was the basis for an order placed in September 1939 for the XP-46. The requirements called for a single-engine, low-wing aircraft, slightly smaller than the P-40, and with a wide-track, inward-retracting landing gear. The selected powerplant was a 1,150 hp (858 kW) Allison V-1710-39 V-12 engine. The planned armament included two .50 in (12.7 mm) synchronized machine guns in the forward fuselage and provisions for eight .30 in (7.62 mm) wing-mounted guns. The USAAC later added requirements for self-sealing fuel tanks and 65 lb (29 kg) of armor, the weights of which were to adversely affect performance.

Testing

Two prototype aircraft were delivered, designated XP-46A, with the first flight occurring on 15 February 1941. However, the USAAC decided in July 1940 (while the XP-46s were under construction) to replace the XP-46 procurement effort with an upgraded P-40 which would use the planned XP-46 engine. In this manner, a serious disruption of the Curtiss production line would be avoided.

In 1940 the British Purchasing Commission had placed an order for P-46s as a replacement for the P-40, which had been ordered for the RAF as the 'Tomahawk', although the British order for P-46s was later cancelled.^[1]

While early models of the P-40 were being produced, Curtiss began testing a follow-on design, the XP-46. As it offered no particular improvements over the latest P-40s, the program was cancelled.^[2] The performance during trials of the XP-46 was subsequently found to be inferior to the upgraded P-40 (designated P-40D).

A myth surrounding the origins of the North American P-51 Mustang is linked to the North American Aviation (NAA) purchase of test data on the P-40 and P-46. NAA paid $56,000 to Curtiss for technical aerodynamic data on the XP-46 and although there are certain design similarities in the radiator/oil-cooler configuration, the new NA-73X (the company designation for the future P-51) even in preliminary design had already progressed beyond the XP-46.^[3] In addition, after the war, NAA engineers revealed that they had learned of a European study (before the US entry into World War II) which indicated the value of a well-designed embedded radiator, and were eager to apply that knowledge - the Meredith effect - to a new design.

Specifications (Curtiss XP-46A)

XP-46 side view

Data from Curtiss Aircraft 1907–1947^[4]

General characteristics

• Crew: one
• Length: 30 ft 2 in (9.19 m)
• Wingspan: 34 ft 3¾ in (10.45 m)
• Height: 10 ft 1 in (3.07 m)
• Wing area: 208 ft² (19.32 m²)
• Empty weight: 5,625 lb (2,551 kg)
• Max. takeoff weight: 7,665 lb (3,477 kg)
• Powerplant: 1 × Allison V-1710-39 liquid-cooled V12 engine, 1,150 hp (858 kW)

Performance

• Maximum speed: 355 mph (309 knots, 571 km/h) at 12,200 ft (3,720 m)
• Range: 325 mi (283 nmi, 523 km)
  
• Climb to 12,300 ft (3,750 m): 5 min

Armament

• Guns:
  
  • 2 × .50 in (12.7 mm) synchronized machine guns in the forward fuselage
  • Provision for 8 × .30 in (7.62 mm) wing-mounted guns

See also

References

Notes

Bibliography

External links

Wikimedia Commons has media related to Curtiss XP-46.

• Curtiss XP-46