Forty-six B-29s of this variant, built by the Glenn L. Martin Company at its Omaha plant, were used as the aircraft for the atomic bomb missions, modified to Silverplate specifications. Some 2,513 B-29s were manufactured by Boeing-Wichita (1,620), Bell-Atlanta (357), and Martin-Omaha (536). B-29A Section source: Baugher The B-29A was an improved version of the original B-29 production model. This is the definitive wartime variant of the B-29. All 1,119 B-29A's were built at the Boeing plant in Renton, Washington, formerly used by the United States Navy. Enhancements made in the B-29A included a better wing design and defensive modifications. Due to a demonstrated weakness to head-on fighter attacks, the number of machine guns in the forward dorsal turrets was doubled to four. Where the wings of previous models had been made by the sub-assembly of two sections, the B-29A wing was built up from three. This made construction easier, and increased the strength of the airframe. The B-29A was produced until May 1946, when the last aircraft was completed. It was much used during the Korean War, but was quickly phased out when the jet bomber (B-47 Stratojet) became operational. Washington B Mk 1 – This was the service name given to 88 B-29As supplied to the Royal Air Force. B-29B Section source: Baugher's Encyclopedia & National Museum of the USAF The B-29B was a modification used for low-level raids, designed with the intent of firebombing Japan. Since fighter opposition was minimal over Japan in late 1944, many of the Army Air Force leadership — most notably Curtis LeMay, commander of the XXI Bomber Command — felt that a (lighter) faster bomber would better evade Japanese flak. In the B-29B, as with the atomic raid-dedicated Silverplate versions earlier, all defensive armament was removed except for that in the tail turret. Initially the armament was two .50 in AN/M2 machine guns and one 20 mm M2 cannon which was soon changed to three .50 in AN/M2s. The weight saved by removing the guns increased the top speed from 357 mph to 364 mph (575 km/h to 586 km/h). Also incorporated on this version was an improved APQ-7 "Eagle" bombing-through-overcast radar that was fitted in an airfoil-shaped radome under the fuselage. All 311 B-29Bs were built at the Bell plant in Marietta, Georgia ("Bell-Atlanta"). B-29C The B-29C was a modification of the B-29A re-engined with improved Wright R-3350 engines. The Army