In overall configuration, the Brewster Model 340 was very similar to its predecessor, with a mid-wing, inward-retracting landing gear and internal weapon bay. The shapes of the major components were also similar, but the overall dimensions were increased to double the internal bomb-load to 1,000 lb (454 kg) and to permit installation of the 1,700 hp Wright R-2600-8 Cyclone two-row radial. Another innovation in the Model 340 design was the provision for a power-operated turret in the fuselage aft of the wing, taking the place of the open gun positions in the SBA-1.
The US Navy ordered a prototype of the new Brewster design on April 4, 1939, with the designation XSB2A-1 (BuNo 1632), and this aircraft made its first flight on June 17, 1941, powered by a 1,700 hp Wright R-2600-8 engine. Large-scale production at Brewster's Johnsville factory in Pennsylvania had already started, as the company had succeeded in selling the Model 340 to the British Purchasing Commission which ordered 750 in July 1940 as Bermudas, and to the Dutch Government which ordered 162 for the Royal Netherlands Indies Army.
On December 24, 1940, the USN ordered 140 aircraft, and during 1941, after passage of the Lend-Lease Act through Congress, the USAAF and USN jointly assumed responsibility for the aircraft which had been ordered by Britain. Production aircraft dispensed with the dorsal turret, which was only ever carried in dummy form by the prototype.
During 1943 the USN began accepting 80 SB2A-2s, similar to the SB2A-1 but having two 0.50 in (12.7 mm) caliber nose guns and only two 0.30 in (7.62 mm) wing guns plus the two dorsal 0.30s. Final production variant was the SB2A-3, ordered in 1942 and delivered early in 1944; the sixty aircraft of this type had folding wings and arrester hooks, making them the only Buccaneers capable of carrier operations.
Meanwhile, the 162 Dutch aircraft had been repossessed by the USN before delivery and designated SB2A-4. Lacking some of the equipment of the SB2A-2, these aircraft were somewhat lighter and carried the original armament of eight 0.30s. They were used as trainers by Marine squadrons, particularly VMF(N)-531, the first Marine night fighting unit. There are no records to show that any of 771 Buccaneers and Bermudas were ever involved in combat."
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