Curtiss YP-37

YP-37
Curtiss YP-37
General information
TypeFighter
National origin
United States
ManufacturerCurtiss-Wright Corporation
StatusCanceled
Primary userUnited States Army Air Corps
Number built14
History
Introduction date
1939 (YP-37)
First flightApril 1937 (XP-37)
Developed from
Curtiss P-36 Hawk

The Curtiss YP-37 was an American fighter aircraft developed by Curtiss-Wright in the late 1930s for the United States Army Air Corps (USAAC). A derivative of the Curtiss P-36 Hawk, the YP-37 was designed to improve performance by replacing the P-36's radial engine with a turbo-supercharged, liquid-cooled Allison V-1710 inline engine, resulting in a lengthened fuselage and a rearward-shifted cockpit. Although it demonstrated promising speed, the aircraft suffered from unreliable turbo-superchargers and poor visibility, leading to its cancellation after 14 units were built. The project was abandoned in favor of the more practical Curtiss P-40 Warhawk.

Design and development

In early 1937, recognizing the P-36 Hawk's inferiority to emerging European fighters like the Supermarine Spitfire and Messerschmitt Bf 109, the USAAC sought to enhance its fighter capabilities. Curtiss was tasked with adapting a P-36 airframe to use a turbo-supercharged Allison V-1710-11 engine, producing 1,150 hp (860 kW). The prototype Hawk was fitted with a turbo-supercharged 1,150 hp (860 kW) Allison V-1710-11 as the XP-37 (company designation Model 75I). The cockpit was moved back towards the tail to make room for the massive turbo-superchargers, and the engine was cooled by two radiators on either side of the nose. It was armed with one 0.30 in (7.62 mm) M1919 Browning machine gun and one 0.50 in (12.70 mm) M2 Browning machine gun in the nose. The XP-37 first flew in April 1937, achieving a top speed of 340 mph (547 km/h), but its turbo-supercharger was prone to failure, and visibility was severely limited.

Intrigued by the speed potential, the USAAC ordered 13 service-test YP-37 aircraft in 1938 for $531,305.12. These featured an improved V-1710-21 engine and a further extended nose to adjust balance. First flown in June 1939, the YP-37 retained the same armament but failed to resolve the reliability and visibility issues. By 1940, the USAAC canceled the project, shifting focus to the P-40 Warhawk, which used a simpler Allison engine configuration.

Variants

XP-37
One prototype with a V-1710-11 engine.
YP-37
13 service-test aircraft with V-1710-21 engines and an extended fuselage.

Specifications (YP-37)

Data from Curtiss aircraft 1907–1947, Baugher: Curtiss XP-37

General characteristics

Performance

331 mph (288 kn; 533 km/h) at 20,000 ft (6,100 m)

Armament

See also

Related development

References

  1. 1 2 3 Bowers, Peter M. (1987). Curtiss aircraft, 1907-1947. London: Putnam. pp. 348–365. ISBN 9780851778112.
  2. 1 2 Baugher, Joe. "Curtiss XP-37". www.joebaugher.com. Retrieved February 24, 2025.
  3. ↑ "ARMY AIR CORPS BUYS PURSUIT AIRPLANES". Air Corps News Letter. XXI (1). Air Corps Munitions Building, Washington, D.C.: Information Division USAAC: 2. 1 January 1938.
  4. ↑ Lednicer, David. "The Incomplete Guide to Airfoil Usage". m-selig.ae.illinois.edu. Retrieved 16 April 2019.