The base was the location of the first of twenty-eight stations built by ADC as part of the permanent air defense radar network, and was the top-priority site for ADC radars. The 505th Aircraft Control and Warning Group, the first postwar general surveillance radar organization was activated at McChord on 21 May 1947. Defensive warning radars became operational at McChord on 1 June 1950 with World War II-era AN/CPS-4 and AN/CPS-5 radars being operated by the 635th Aircraft Control and Warning Squadron. ADC completed installation of two AN/CPS-6B medium-range search and height-finder radars in February 1951. Performance of these new radars was deemed inferior to the World War II vintage models and the calibration process delayed operational readiness at this and other sites. An AN/FPS-6 height-finder radar was installed in the mid-1950s.