 The WSR-1A, WSR-3, and WSR-4 were also variants of this radar.The first WSR-1 in the USA was at Washington National Airport in Washington, D.C. in 1947, and the last WSR-3 was retired by 1978.In 1946, the US Weather Bureau (ancestor of the National Weather Service) retrieved 25 AN/APS-2F aeronautical radars from the US Navy.