Boeing B-29 Superfortress (1944)

Pending the arrival of significant numbers of Avro Lincolns, 88 ex-USAF B-29s were loaned to the RAF between 1950 and 1955 under the name Washington B.Mk 1. This aircraft was assigned to No.90 Squadron at RAF Marham, one of eight squadrons equipped with Washingtons.

Even without the atomic missions that the type flew against Japan in August 1945, the B-29 – the most advanced heavy bomber of the war – can be considered a war-winner on account of the devastating raids it conducted against the Japanese mainland in the preceding months.

Following the outbreak of war in Europe, in 1939 the U.S. Army Air Corps issued a requirement for a Very Heavy Bomber, a strategic bomber capable of carrying 9072kg (20,000lb) of weapons over a distance of 8582km (5333 miles) at a speed of 644km/h (400mph). When the Japanese attacked Pearl Harbor, the project assumed priority status. By now, the Very Heavy Bomber had been renamed as the Very Long Range project, with a view to deployment over the vast distances of the Pacific theatre.

After receiving the go-ahead from USAAC chief Henry H. ‘Hap’ Arnold, the project got underway in early 1940. Requests for proposals were issued to five manufacturers in January of that year, with contracts awarded to Boeing and Consolidated for the construction of two (later three) prototypes. The first of these to fly was the Consolidated XB-32, but it suffered development delays that led to a protracted service entry.

As of 1940, Boeing’s design had advanced much further than that of rival Consolidated, and the manufacturer convinced the USAAC that the finished aircraft would be available within two or three years. The big new four-engined bomber was soon ordered in significant numbers, with a request for 1500 examples received even before the first flight of a prototype XB-29, which occurred in September 1942. Among the futuristic features of the B-29 were its electrically-retractable tricycle undercarriage, pressurized accommodation for the crew and defensive gun turrets that were sighted from adjacent blister windows. The powerplant consisted of four Wright R-3350 Cyclone twin-row radial piston engines, each unit being provided with two superchargers.

In May 1943 plans were drawn up to employ the Superfortress exclusively in combat against Japan. As a result, production B-29 bombers were to be assigned to the 20th Air Force at bases in China and India. The initial aircraft delivered to service units were taken from the batch of 14 YB-29 test aircraft, the first of which flew in June 1943, and which were accepted by the 58th Very Heavy Bombardment Wing in July 1943.

The first true production bombers were the B-29-BW aircraft that were manufactured by Boeing at Wichita and at a new plant in Renton, as well as by Bell in Marietta and Martin in Omaha. In addition to these final-assembly plants, the Superfortress production effort made use of over 60 new factories, all of which provided major components as part of a complex supply chain.

The first B-29s were deployed in theatre in early 1944, initially in India. From here, the Superfortress made a first raid in June 1944 against Bangkok. A first raid on the Japanese mainland was undertaken later in the same month, flying from a hastily prepared base in Chengdu, China. In October 1944 the B-29s began flying missions against Japan from bases on Tinian, Saipan and Guam – newly captured islands in the Marianas chain.

Devastating Raids

During their initial nine months of service, the B-29s were employed mainly for high-level daylight raids, but tactics switched in March 1945, when they began low-level night attacks from the Marianas islands. These were the most destructive raids of the war in terms of casualties, with the first night-time incendiary raid on Tokyo killing around 80,000 people.

Total B-29 production amounted to 3970 aircraft. Two main sub-variants appeared during the war, the Renton-built B-29A-BN with a four-gun forward upper turret, changes to the fuel system and increased wingspan, and the Marietta-built B-29-BA with an increased bombload but a reduced gun armament to bring down its weight.

It was two Omaha-built B-29-45-MOs, named Enola Gay and Bock’s Car, of the 393rd Bombardment Squadron, that were responsible for dropping the atomic bombs Little Boy and Fat Man on the cities of Hiroshima and Nagasaki on 6 and 9 August 1945, respectively.

A total of 118 B-29s were converted for reconnaissance duties, being equipped with cameras and serving as F-13 and F-13A aircraft. These were used to provide reconnaissance for raids on Japan from December 1944.

B-29s remained in use after the war, converted for several other duties including in-flight refuelling, weather reconnaissance and rescue. The B-29 saw military service again in Korea between 1950 and 1953. The final example was retired from service in September 1960.

After the War

While many of the B-29s completed before the end of the war met this fate, some of them being disposed of direct from the production line, the Superfortress continued to provide useful service to the post-war Air Force. The B-29 was used in 1950–53 in the Korean War. At first, the bomber was used in normal strategic day-bombing missions, though North Korea’s few strategic targets and industries were quickly reduced to rubble. More importantly, in 1950 numbers of Soviet MiG-15 jet fighters appeared over Korea, and after the loss of 28 aircraft, future B-29 raids were restricted to night-only missions, largely in a supply-interdiction role. Over the course of the war, B-29s flew 20,000 sorties and dropped 200,000 tonnes (180,000 tons) of bombs. B-29 gunners were credited with shooting down 27 enemy aircraft.

In addition to their primary strategic bombing role, a total of 92 aircraft were converted to KB-29M tanker configuration, with a hose and reel in the aft fuselage. This was followed by the KB-29P (116 conversions), a tanker that made use of the ‘flying boom’ method, involving an operator that ‘flew’ the boom nozzle into a receptacle on the receiving aircraft.