The Curtiss-Wright-CW-21 was a single seat, all-metal cantilever low-wing monoplane with rearward retracting landing gear and was powered by a 1,000 hp (746 kW) Wright Cyclone R-1820-G5 nine cylinder air-cooled radial engine.
In 1940, The Netherlands ordered 24 examples of a modified version designated the CW-21B (together with a number of two-seat CW-22), for the Royal Netherlands East Indies Army Military Aviation (Militaire Luchtvaart van het Koninklijk Nederlands-Indisch Leger; ML-KNIL).
