Curtiss-Wright CW-21

The Curtiss-Wright CW-21 Interceptor (also known as the Curtiss-Wright Demon) was a United States-built interceptor fighter plane, developed by the Curtiss-Wright Corporation during the 1930s.

Curtiss-Wright CW-21
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Type	fighter
Manufacturer	Curtiss-Wright Corporation
Maiden flight	January 1939
Introduced	1939
Status	Retired
Primary users	Chinese Air Force Militaire Luchtvaart KNIL
Produced	1939-1940
Number built	62

Design and development

The CW-21 was not commissioned by the U.S. military; it was developed for export sales by the St. Louis Airplane Division of Curtiss-Wright. The aircraft was a single engined, low-wing monoplane with rearward retracting landing gear, and was powered by a 1,000 hp (750 kW) Wright Cyclone nine cylinder air-cooled radial Wright R-1820-G5 engine.

The CW-21 Interceptor was based on the CW-19R two seat, general-purpose military monoplane. A prototype flew in January 1939 and bore the civil experimental registration NX19431. The prototype was designed to carry various combinations of two 0.3 or 0.5 inch (7.62 or 12.7 mm) machines guns, mounted in the nose and synchronized to fire through the propeller.

Chinese service

The first sale of the CW-21 Demon, in 1939, was to the Chinese Air Force, which received three completed examples and kits for 32 more. These were armed with one 0.3 and one 0.5 inch (12.7 mm) machine guns. Three other CW-21Bs were furnished to the Chinese as kits, assembled in Loi-Wing, that were delivered to the American Volunteer Group (Flying Tigers). But these crashed in poor visibility on the delivery flight from Rangoon on 23 December 1941.

Netherlands East Indies service

In 1940, The Netherlands ordered 24 examples of a modified version designated the CW-21B (together with a number of two-seat CW-20s), for the Royal Netherlands East Indies Army Military Aviation (Militaire Luchtvaart van het Koninklijk Nederlands-Indisch Leger; ML-KNIL).

The modifications consisted of inward retracting landing gear, a semi-retractable tail wheel, two each 0.3 and 0.5 inch (7.62 and 12.7 mm) machine guns, and a slightly large fuel tank. These changes gained an eight mph (13 km/h) speed increase at sea level.

Deliveries started in June 1940 but only 17 had been received by Vliegtuigroep IV, Afdeling 2 (No. 2 Squadron, Air Group IV; 2-VlG IV), when war with Japan began on 8 December 1941. With its rudimentary pilot protection, no self-sealing fuel tanks and light construction, the CW-21B was not unlike the opposing Japanese planes. It had better firepower than the Nakajima Ki-43 "Oscar", but worse than the cannon-armed Mitsubishi Zero. Its climb rate was far better than either.

Specifications (CW-21B)

General characteristics

• Crew: one, pilot
• Length: 27 ft 2 in (8.3 m)
• Wingspan: 35 ft (10.7 m)
• Height: 8 ft 11 in (2.7 m)
• Wing area: 174.3 ft² (16 m²)
• Empty: 3,382 lb (1534 kg)
• Loaded: 4,500 lb (2041 kg)
• Powerplant: one Wright Cyclone R-1820-G5 nine cylinder radial air-cooled engine 1,000 hp (750 kW)

Performance

• Maximum speed: 315 mi/h (506 km/h) at 17,000 ft (5200 m)
• Range: 630 statute miles (1010 km)
• Service ceiling: 34,300 ft (10,500 m)
• Initial rate of climb: 4,500 ft/min (1400 m/min)
• Power/mass: 1,000 hp (750 kW)

Armament

• Two each 0.3 and 0.5 in (7.62 and 12.7 mm) Browning M-2 machine guns

References

• Green, William. War Planes of the Second World War - Fighters (Vol 4). London: MacDonald, 1961.
• Taylor, John W. R. "Curtiss-Wright CW-21." Combat Aircraft of the World from 1909 to the present. New York: G.P. Putnam's Sons, 1969. ISBN 0-425-03633-2.