Enola Gay B-29 airplane model. 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. Boeing installed very advanced armament, propulsion, and avionics systems into the Superfortress. During the war in the Pacific Theater, the B-29 delivered the first nuclear weapons used in combat. On August 6, 1945, Colonel Paul W. Tibbets, Jr., in command of the Superfortress "Enola Gay," dropped an atomic bomb on Hiroshima, Japan. Three days later, Major Charles W. Sweeney piloted another B-29 named "Bockscar" and dropped a second atomic bomb on Nagasaki, Japan. On August 14, 1945, the Japanese accepted Allied terms for unconditional surrender.