The Boeing B-29 Superfortress is an American four-engined propeller-driven heavy bomber designed by Boeing and flown primarily by the United States during World War II and the Korean War. One of the largest aircraft of World War II, the B-29 had state-of-the-art technology, including a pressurized cabin, dual-wheeled, tricycle landing gear, and an analog computer-controlled fire-control system that allowed one gunner and a fire-control officer to direct four remote machine gun turrets.