The U.S. Air Force returned with Boeing KC-135 Stratotankers deployed on rotation from the many KC-135 bases in the USA. On 15 November 1978 the 11th Strategic Group (11 SG) was activated at RAF Fairford. It was not manned until the following February and used KC-135 aircraft and crews from SAC, Air National Guard, and AF Reserve units until the 11 SG received its own aircraft in September 1979. It soon began aerial refueling support for all USAF operations, deployments and redeployments, as well as participating in NATO exercises.