The Convair B-58 Hustler was the first operational supersonic jet bomber capable of Mach 2 flight. The aircraft was designed by Convair engineer Robert H. Widmer and developed for the United States Air Force for service in the Strategic Air Command (SAC) during the 1960s. It used a delta wing, which was also employed by Convair fighters such as the F-102, with four General Electric J79 engines in pods under the wing. It carried a nuclear weapon and fuel in a large pod under the fuselage rather than in an internal bomb bay. Replacing the Boeing B-47 Stratojet medium bomber, it was originally intended to fly at high altitudes and supersonic speeds to avoid Soviet fighters. The B-58 received a great deal of notoriety due to its sonic boom, which was often heard by the public as it passed overhead in supersonic flight.