The SB2U scout bomber was one of the first monoplanes used by the US Navy. It was contracted 1934 and first flew in 1936. Three versions were quickly developed and delivered to the Navy and the Marine Corps. The SB2U-3 had increased fuel capacity, provisions for long-range drop tanks, .50-caliber guns and increased armor protection. Woefully obsolete by the beginning of World War II and eclipsed by the better performing Northrop BT-1 and its successor, the Douglas SBD Dauntless, the Vindicator saw limited use.