 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.