was assigned to the USAAF's Second Air Force under the XX Bomber Command. On 12 April 1944, the Marietta Army Airfield was reassigned to the "17th Bombardment Operation Training Unit". In the spring of 1943 the adjacent Bell Aircraft Company's factory, an additional plant (besides a pair of Boeing plants Renton, Washington and Wichita, Kansas (former Stearman Aircraft) and a Martin plant at Offutt Field, Omaha, Nebraska) for manufacturing B-29 Superfortresses was completed. The "Defense Plant Corporation" of the Department of War paid for the construction of this factory, and the Department called it "Plant #6". Bell Aircraft completed its first B-29 on schedule, and this was first test-flown on November 4, 1943. The production of B-29s at this factory increased slowly during 1944, and by the fall of 1944, Bell Aircraft's output of new B-29s began to meet and exceed the goals of the Department of War. By January 1945, Bell Aircraft had completed 357 B-29A's. After the completion of the last one of these, the production in Marietta was switched to the B-29B Superfortress, which was a simplified version of the B-29 without the computerized gun system and other components that raised the allowable bomb load from 11,000 to 18,000 pounds. The new B-29B radar, mounted in a wing-shaped radome under the fuselage, gave much better images of the ground. The 315th Bombardment Wing based at Northwest Field, Guam, received most of the B-29Bs for night low altitude pathfinder led missions against Japan. Bell built a total of 311 B-29Bs before the plant closed in January 1946. At its height, the Bell Bomber plant employed 28,263. Post-war Marietta Army Airfield remained open after the war and became the home of Georgia Air National Guard (ANG) and Air Force Reserve units. The first post-war ANG unit, the 128th Fighter Squadron, activated at Marietta on 20 August 1946, with P-47 Thunderbolts. This was followed by the activation of the headquarters of the 116th Fighter Group on 9 September and the activation of the headquarters of the 54th Fighter Wing which commanded 56 units of the Air National Guard throughout the Southeastern states. In 1948, part of the land and barracks at the original Naval Air Station Atlanta in nearby Chamblee were given to the state for the purpose of creating an engineering technology school that could rapidly train returning soldiers for civilian work in various technical fields. Also in 1948