The Boeing B-29 "Superfortress" will forever be linked to the atomic bombs dropped on the Japanese cities of Hiroshima and Nagasaki to help end World War 2 ("Bock's Car" and the "Enola Gay" were the selected aircraft). However, before the B-29 signaled the beginning of the end of the conflict, it served as a nearly untouchable, high-altitude, heavy bombing platform with revolutionary technologies incorporated throughout her impressive design. The Boeing B-29 only served in the Pacific Theater against the Empire of Japan during the war and was never called to action over Europe as the war against Germany was winding down by April-May of 1945. However, the bomber series would go one to serve extensively throughout the upcoming Korean War (1950-1953), solidifying its place in American military aviation history.
The B-29, like the Boeing B-17 Flying Fortress before it, was developed to a US Army Air Corps (USAAC) requirement for a high-level heavy bomber capable of extended operational ranges and increased payloads while operating at speeds nearing 400 miles per hour. The range requirement was of particular note due to the vast distances encountered in the Pacific. The B-29 program began slowly and appeared prior to America's entry into World War 2. After the Japanese attack on Pearl Harbor (December 7th, 1941), the B-29 program was pushed into full gear as the need for modern bombers was apparent. The first of three "XB-29" prototypes took to the air in 1942 with government orders already secured for over 1,500 production-quality units.
The B-29 Superfortress was a mid-wing monoplane design centered around a tubular fuselage powered by four large air-cooled radial piston engines. The pencil-like fuselage was heavily-glazed at the nose and provided the characteristic appearance for the series. Crew accommodations included ten personnel made up of pilots, bombardiers, navigators, specialists and dedicated gunners. All weapon systems were held in electrically-powered turret "barbettes" operated by way of integrated periscopes and fitted in dorsal, ventral and tail gun positions. This armament arrangement represented a vast departure from any bomber defenses fielded during the war, though necessitated by the B-29's high operating altitude (the B-17 still utilized some open-air machine gun ports, exposing the crew to the bitter cold temperatures of high-level flight).
Several modified - or converted - models of the B-29 were used exclusively for crew training, as dedicated Search and Rescue (SAR) systems, dedicated reconnaissance platforms outfitted with camera and weather survey platforms before the end of the aircraft's production run.
By the time of the Korean War, daylight bombing runs had become becoming increasingly costly to B-29 crews due to the arrival of the Soviet-built, single-seat, jet-powered Mikoyan-Gurevich MiG-15 "Fagot" fighters. As such, night time bombing campaigns grew in number as the B-29 continued serving under the new USAF Strategic Air Command (SAC).
The B-29 fitted a bevy of 12.7mm Browning M2 heavy machine guns for self-defense. Four were installed in an electrically-operated dorsal turret while a second dorsal turret fitted two more. A pair of 12.7mm machine guns were installed in a chin position with another two-gun system mounted under the rear fuselage. A pair of machine guns were installed in the tail to counter any incoming interceptors. Beyond these guns, the B-29's true value came in her ability to carry up to 20,000 lb of internally-held ordnance.
American authorities limited the B-29s combat action solely to the Pacific Theater during World War 2. Operational B-29s were being delivered to front lines as early as 1943 (these being largely service evaluation aircraft) and were utilized into 1944 as daylight, high-level bombers. Early sorties originated from bases in British India against Japanese targets in Thailand and, later, against targets on the Japanese mainland. Night time, low-level attacks were next on the B-29's agenda and such sorties against Japanese cities and military production facilities proved utterly lethal - a single fire-bomb attack by 279 Superfortresses killed upwards of 80,000 Japanese.
Production of B-29 Superfortress was split between several factories managed under different contractors to keep up with demand. This would ultimately include Boeing, Bell, and Martin - all being military aircraft powerhouses during this period - and production totaled nearly 4,000 examples before the end of the run. An improved B-29 model appeared in the years following the war and this example was designated the "B-50". Outwardly similar to the original B-29, the B-50 was completed with some 75% of the airframe newly designed, hence her all-new designation. The B-50 was differentiated from her predecessor by a revised vertical tail fin as well as more powerful engines. Additionally, the B-50's structure was further strengthened. This variant appeared in 1948 and was produced in about 370 examples up until 1953.
Beyond the United States, the United Kingdom and Australia both utilized the B-29 Superfortress in their respective air service inventories. The Soviet Union, always willing to gain more ground in the technology field against its American adversaries, reverse-engineered B-29s from three captured examples forced to land in Soviet territory after raids over Japan (among these was the "Ramp Tramp"). On Stalin's orders, the Tupolev concern took up the task and worked out the Boeing product right down to the final rivets - resulting in the Tupolev Tu-4 "Bull" which, itself, spawned the Tupolev Tu-70 dedicated transport platform. By all accounts, the Tu-4 was nothing more than an inferior copy of the excellent American product but nonetheless advanced the Soviet bomber program considerably.
The B-29 proved a critical design achievement for the American military, particularly concerning actions in World War 2 and Korea (1950-1953). It undoubtedly lay the ground work for future projects that would ultimately culminate in the world-renowned Boeing B-52 "Stratofortress" of Vietnam War (1955-1975) fame. The B-52 essentially marked the end of the dedicated Boeing "heavy bomber" era as the mantel was eventually taken over by the sleek swing-wing Rockwell B-1 "Lancer" and the technologically-advanced Northrop B-2 "Spirit" stealth bomber and missile-launching warships and submarines. Despite this, the B-52 continues to fly in a frontline role today.