Boeing B-29 Superfortress

With tensions across the world rising, the issue of long-range bombers was discussed by the United States Army Air Corps, with the aircraft potentially being required to operate over the Pacific Ocean. This led to the release of Specification AC-219 on the 29th January 1940. This called for an aircraft which had a top speed of 400 mph, a range of 2,500 miles and could carry 20,000lb bombs.

Six companies, Boeing, Consolidated, Douglas, Lockheed, Martin and Sikorsky had proposals sent to them for designs, with Martin and Sikorsky the only companies not to submit a design, while both Douglas and Lockheed later withdrew their submissions. This left Boeing's XB-29 and Consolidated's XB-32 Dominator to be compared, and by the time an initial order of two prototypes of each, and one static test airframe XB-29, was placed on the 6rh September 1940, the specification had been modified. This was as a result of intelligence gathered about the air war over Europe, with self-sealing fuel tanks and an increase in defensive armament among the changes.

Two months later, in November 1940, a further XB-29 prototype was ordered, bringing the total to three flying and one static airframe. This was followed on the 1st May 1941 for an order for 250 aircraft, fourteen YB-29s were also ordered during 1941, and orders totalling 1,665 had been placed for the B-29 by September 1942. The 7th September 1942 saw the XB-32 Dominator make its first flight, fourteen days before Boeing's XB-29. However, the XB-32 required more development, so it was the B-29 that would be ordered in large numbers, with only 118 B-32s built.

Flying from Boeing Field, piloted by Edmund Allen, the first XB-29 prototype made its maiden flight on the 21st September 1942. While the first XB-29 prototypes first flight had gone well, the same could not be said for the second XB-29 prototype. On its maiden flight, on the 30th December 1942, an engine fire broke out, an engine fire would lead to the loss of the second XB-29 prototype on the 18th February 1943. This claimed the lives of Edmund Allen and ten crew members and twenty people on the ground. Engine issues would hamper the B-29's development. The final flying prototype was ready by May 1943.

The B-29 would normally have a crew of eleven, consisting of pilot, co-pilot, navigator, bomb-aimer, flight engineer, wireless operator, radar operator, top gunner, two side gunners and a rear gunner and featured pressurised cabins. Some of the aircraft's armament were gun barbettes, which were remote control. The gunners looked through a gun sight, separate to the turret, at their target and a computer would calculate the correct trajectory when firing. This system allowed one crew member to operate two guns at the same time. It had been decided during 1943 that the B-29 would be used solely in the Pacific during the Second World War (1939 – 1945), with March 1944 seeing the aircraft named the B-29 Superfortress.

The 1st May 1943 had seen the 58th Bombardment Operational Training Wing (Heavy), based at Smoky Hill Army Airfield, formed. They would take delivery of the YB-29s, the first of which flew in June 1943, so they could get the type ready for operational service. Two months after its formation, in July 1943, the 58th Bombardment Operational Training Wing (Heavy) was renamed the 58th Bombardment Wing (Heavy).

The B-29 was powered by the 2,200-hp Wright R-3350-23 Cyclone engine, its top speed was 358 mph, range 3,250 miles with a service ceiling of 31,850 ft. Armament was one 20mm cannon and ten 0.50-in machine-guns, bomb load was 20,000lb.

The B-29A, also known as the Washington B Mk I, followed, it was powered by the 2,200-hp Wright R-3350-28 Cyclone engine, giving the aircraft a top speed of 357 mph, a range of 4,100 miles and a service ceiling of 33,600 ft. Armament consisted of one 20 mm cannon and twelve 0.50-in machine-guns, with a bomb load of 20,000lb.

The aircraft entered United States Army Air Force service on the 8th May 1944. The following month, on the 5th June 1944, the B-29 performed its first operational sortie. Operating from airfields in India, ninety eight aircraft, from the 58th Bombardment Wing (Very Heavy), targeted railway yards in Bangkok, Thailand, losing five aircraft. Ten days later, on the 15th June 1944, the B-29 performed its first raid on mainland Japan, when sixty eight aircraft from the 58th Bombardment Wing (Very Heavy), now operating from airfields in China, targeted the Imperial Iron and Steel Works at Yawata, Kyushu.

Operating from airfields in China proved difficult, particularly providing the necessary supplies, so no concentrated B-29 campaign could be undertaken. It wouldn't be until the capture of Saipan, Guam and Tinian, part of the Mariana Islands in July 1944 and August 1944 and the building of airfields on these islands that the B-29 could be deployed in larger numbers.

January 1945 saw production of the B-29B begin. Powered by the 2,200-hp Wright R-3350-41 Duplex Cyclone engine, its top speed was 364 mph, range 4,200 miles with a service ceiling of 32,000 ft. Armament was one 20mm cannon and two 0.50-in machine-guns in a rear turret, bomb load was 20,000lb.

The number of B-29s being used in the bombing campaign against Japan increased and on the 9th March 1944, flying from airfields on the Mariana Islands, 334 B-29s attacked Tokyo, Japan. As a result, around 80,000 people died.

The B-29 was chosen to drop the atomic bombs, in fact, the aircraft cost more to develop than the atomic bomb, and two B-29s from the 393rd Bombardment Squadron carried out the task. The Enola Gay, piloted by Colonel Paul Tibbets, would drop the first atomic bomb on Hiroshima, Japan on the 6th August 1945. Over 70,000 people died, with around 70,000 people dying as a result of the raid in the days and weeks that followed. Three days later, on the 9th August 1945, Bockscar, piloted by Major Charles Sweeney, dropped the second atomic bomb, this time on Nagasaki, Japan. Between 60,000 – 80,000 people died as a result. Shortly after these events, the Second World War came to an end, officially on the 2nd September 1945.

B-29s would remain in service with the United States Army Air Force post-war and would see action during the Korean War (1950 – 1953) and a number would serve with the Royal Air Force, known as Washington B Mk Is.

In total, 3,970 B-29s had been built by the time production ended in May 1946.