Curtiss-Wright CW-21 Demon Fighter / Interceptor Aircraft
Developed for export, the Curtiss-Wright CW-21 Demon held many faults in its attempt to stay a lightweight interceptor.
Authored By Staff Writer; Content ©www.MilitaryFactory.com
In the pre-World War 2 world, engineers at Curtiss-Wright began work on an export-minded, single-seat, single-engine fighter-interceptor influenced by the company's previous twin-seat "Model 19" utility aircraft. Performance was to be the key quality of the lightweight design - particularly in its rate-of-climb - affording the pilot the ability to take-off and meet incoming bomber formations in short order and escape potential fighter-versus-fighter dueling if pressed . The aircraft was christened "Model 21" and took on the formal designation of CW-21 "Demon" in sales.
The aircraft was given a typical configuration for the period with its low-set monoplane wings. Metal was incorporated throughout its construction. The radial piston engine, driving a three-blade propeller unit, was fitted to a forward compartment. The pilot sat in a cockpit at amidships looking down the rather long nose assembly. There was a raised fuselage spine aft of the cockpit to incorporate the needed internal volume but this also limited rearward visibility. The cockpit was covered in a framed canopy with decent views of the surrounding area - again limited by the spine, the long nose and the monoplane wings underneath. The fuselage tapered at the rear in the usual way, the tail capped by a small-area rounded vertical fin and low-set horizontal tailplanes. The undercarriage was of the "tail-dragger" configuration that included two main legs under the wings and a small tail wheel. All three systems were retractable into the design with the main legs retracting into underwing fairings. Power was served through a Wright R-1820-G5 9-cylinder, air-cooled radial piston engine of 1,000 horsepower and performance from this was as expected - a maximum speed of 315 miles per hour with a strong rate-of-climb.
The aircraft was to be armed with a combination machine gun arrangement. When first flown on September 22nd, 1938, it was fitted with 1 x 0.50 caliber heavy machine gun and 1 x 0.30 caliber medium machine gun in the engine cowling. Conversely, a customer could accept a fighter with 2 x 0.50 machine guns or 2 x 0.30 machine guns as needed. In any case, both machine gun mounts were synchronized to fire through the spinning propeller blades which limited their rate-of-fire but lightened wing loads.
Of mention here is the decision by Curtiss-Wright to delete several key life-saving qualities from the design to maintain its impressive lightweight stature and performance. The aircraft lacked cockpit armoring and self-sealing fuel tanks - two qualities that would become commonplace for any World War 2 classic fighter design. Armament was deliberately lightweight which limited the aircraft's offensive "punch" and overall construction was not as robust as required of a military fighter.
Budget-conscious China took an early interest in the CW-21 and a single prototype was delivered for review. The Chinese liked what they saw and pressed for a procurement contract with Curtiss-Wright. During this time, the prototype was actually fielded in combat against Japanese forces with reportedly good results when the aircraft managed to down an enemy bomber. The contract called for retainment of the single prototype and the addition of three more flyable units. To this was added a contract for twenty-seven operational-quality aircraft - these to be delivered with 2 x 0.50 and 2 x 0.30 machine guns as standard armament. Manufacture of the batch would be conducted locally at a Chinese plant using kits delivered by Curtiss-Wright.