 The group focused on defending the Oak Ridge atomic plant and Alcoa aluminum production site.In July 1957 the 355th was reduced to a single fighter squadron when the 469th was inactivated.Regular Air Force operations at McGhee Tyson ended on 8 January 1958 when the 355th Group and the 354th Squadron inactivated, and the base was turned over to the Tennessee Air National Guard, which had organized the 134th Fighter Group there the previous month.