Facing a shortage of combat aircraft in January 1940, the British government established the British Purchasing Commission to acquire U.S. aircraft that would help supplement domestic production. Among the U.S. fighter aircraft that caught the Commission's attention was the Brewster. The remaining 32 B-339 aircraft ordered by the Belgians, suspended at the fall of France, were passed on to the United Kingdom. Appraisal by Royal Air Force acceptance personnel criticized it on numerous points including inadequate armament and lack of pilot armor, poor high-altitude performance, engine overheating, maintenance issues, and cockpit controls, while it was praised for its handling, roomy cockpit, and visibility. With a top speed of about 323 mph (520 km/h) at 21,000 ft (6,400 m), but with fuel starvation issues over 15,000 ft (4,600 m), it was considered unfit for duty in western Europe. Still desperately in need of fighter aircraft in the Pacific and Asia for British and Commonwealth air forces, the UK ordered an additional 170 aircraft under the type specification B-339E. The aircraft were sent to Royal Australian Air Force, RAF and Royal New Zealand Air Force fighter squadrons in Singapore, Malaya and Burma, shortly before the outbreak of war with Japan.