Tibbets, Jr., in command of the Superfortress Enola Gay, dropped a highly enriched uranium, explosion-type, 'gun-fired,' atomic bomb on Hiroshima, Japan.

During the war in the Pacific Theater, the B-29 delivered the first nuclear weapons used in combat. Boeing installed very advanced armament, propulsion, and avionics systems into the Superfortress. Boeing's B-29 Superfortress was the most sophisticated, propeller-driven, bomber to fly during World War II, and the first bomber to house its crew in pressurized compartments.