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.