Air Defense Command activated the 740th Aircraft Control and Warning Squadron at Rapid City AFB on 1 February 1953 under the ADC 31st Air Division. The site was located on the base, and was given designation M-97. The site was part of the ADC's planned deployment of 44 mobile radar stations across the United States to support the permanent air defense radar network established during the Cold War. The squadron was reassigned to the 29th Air Division on 16 February 1953, and Rapid City AFB was re-designated Ellsworth AFB.