4620th Air Defense Wing
The 4620th Air Defense Wing (Air Def Wg) is a discontinued wing of the United States Air Force. Its last assignment was with Air Defense Command (ADC) at Santa Monica, California, where it was discontinued in 1961. The wing was organized in 1955 to ensure that the Semi-Automatic Ground Environment (SAGE) air defense system, was compatible with ADC's operational requirements. It also performed operational testing and training on SAGE and earlier systems. Once SAGE started to become operational, the need for the wing no longer existed and it was discontinued, although one of its  subordinate groups continued the SAGE training mission until 1962. History. The 4620th Air Defense Wing was established to implement the Semi-Automatic Ground Environment (SAGE) air defense system, a system of analog computer-equipped direction centers that could process information from ground radars, picket ships and ground observers onto a generated radar scope to create a composite picture of the emerging air battle. The wing was responsible to ensure that SAGE computer systems were based on approved operational concepts for air defense and provided guidance to operational units concerning the implementation, installation, testing, and utilization of SAGE computer programs. Until  December 1958, the wing also provided training on the existing manual air defense control systems that were being replaced by SAGE. The 4620th was originally located with MIT's Lincoln Laboratories, which had developed the SAGE system, to permit close coordination with the organization developing SAGE. In 1957, the 4620th Air Defense Group was organized at Richards-Gebaur Air Force Base, Missouri to manage programming and training for the SAGE system and was assigned to the wing. The wing moved to Santa Monica, California in 1958. Anticipating the wing move to Santa Monica, the 4620th Group was reassigned directly to  ADC. On 15 September, the 4620th group was renumbered as the 4606th Air Defense Group, and continued with that designation until discontinued on 25 June 1962. The wing prepared the operational employment plan for integration of IM-99 Bomarc surface-to-air missiles into the SAGE system. Preceded by extensive planning and testing of almost three years, the first SAGE air defense sector (New York) became operational on 26 June 1958. The first SAGE division (New York) became operational on 1 January 1959. As the SAGE system was becoming fully operational in 1961, the 4620th Wing had completed its mission and  was discontinued.