09/30/2008. Remarks by Johan Visschedijk: "In early 1940, chief engineer Willis Wells of the Curtiss-Wright St. Louis Airplane Division developed the CW-21 single-seat fighter into the CW-21B by incorporating the fully enclosed inward-retracting main undercarriage members and hydraulically-operated flaps developed for the CW-23 basic combat trainer.
On April 17, 1940, twenty-four CW-21Bs were ordered by the Dutch government for use in Holland. As the Netherlands were attacked by Germany on May 10, 1940, and surrendered on May 14, a revised contract was signed on July 11, transferring the aircraft for use by the ML-KNIL (Militaire Luchtvaart van het Koninklijk Nederlands-Indisch Leger, Military Aviation of the Royal Netherlands East Indies Army).
The CW-21B was powered by a 1,000 hp Wright R-1820-G5 Cyclone nine-cylinder air-cooled radial engine and armed with four 0.303 in (7.7 mm) US Colt guns. The first CW-21B, registered NC338, was flown mid-September, 1940, and together with the second aircraft, c/n 2853, registered NC339, it was used for performance flights and firing tests. Later they received the ML-KNIL serials CW-343 and CW-344.
The photo shows the first CW-21B with William E. Nickey, assistant manager of Curtiss-Wright at the controls during an early test flight."