Boeing B-52 Stratofortress B-52B

The B-52B was the first version to enter service with the USAF, on 29 June 1955, with the 93rd Bombardment Wing at Castle Air Force Base, California. It included minor engine and avionics changes enabling an extra 12,000 lbf of thrust with water injection; it was powered by Pratt & Whitney J57-P-29W, J57-P-29WA or J57-P-19W engines, all rated at 47 kN thrust each. The fleet was temporarily grounded after crashes in February and again in July 1956, delaying crew training. Seven B-52Bs were brought up to B-52C standard under "Project Sunflower".