 In the late 1950s, the United States government believed it was significantly behind the USSR in terms of the size of its jet-powered bomber fleet.In response, the USAF had ordered two interceptors from Convair, the F-102 Delta Dagger and the F-106 Delta Dart, but both aircraft were experiencing long development delays.The Starfighter's speed and rate-of-climb performance intrigued the Air Force, who pressed the F-104A into service as an interim interceptor with the Air Defense Command (ADC), even though its range and armament were not well-suited for the role.