sentences:  In 1975 the 112th ended its air defense mission, receiving its first A-7D Corsair II aircraft and was reassigned to the Tactical Air Command.In 1991 with the retirement of the A-7D, the 112th Tactical Fighter Group became the 112th Air Refueling Group (ARG) under Strategic Air Command, receiving KC-135 Stratotankers that it operated jointly with the 171st, which had become an air refueling Wing at Pittsburgh in October 1972.Strategic Air Command was inactivated in June 1992 and the 112th ARG became a part of the Air Mobility Command (AMC).