|
|
In the spring of 1938, a Northrop dive-bomber designated the BT-1 entered service with the US Navy. Its influence was felt over at the Douglas Company, where a new naval dive-bomber was designed and produced based on the Northrop design. Initially designated the XBT-2, the new design was later called the SBD when Northrop became a division of the Douglas Company. Production began in 1940, and although the SBD had a general likeness to its Northrop predecessor, it was a completely different airplane. Testing of the prototype revealed an exceptionally capable airplane. In April 1939, the US Marine Corps and US Navy placed orders for the SBD-1 and SBD-2, the latter having increased fuel capacity and revised armament. The first SBD-1s entered service with the Marines' VMB-2 Squadron in late 1940, and the first SBD-2s joined the Navy in early 1941. The next variant to appear, the SBD-3, entered service in March 1941, and incorporated self-sealing and larger fuel tanks, armor protection, a bullet-proof windshield, and four machine guns. The SBD-4 followed with an upgraded 24-volt electrical system, and a few of these were converted to SBD-4P reconnaissance platforms. The next, and most produced, variant was the SBD-5, which was built at Douglas's new Tulsa, Oklahoma plant. It had a 1,200-hp R-1820-60 engine and increased ammunition capacity. Over 2,400 SBD-5s were built, and a few were shipped to the Royal Navy's Fleet Air Arm, under the designation Dauntless DB.Mk I, but these were never used operationally. Mexico also took delivery of a small number of SBD-5s. The SBD-6, the final variant, had an even more powerful engine and greater fuel capacity.
|