<p>The wing is the controlling element for more than a dozen space warning squadrons located across the USA, and in Germany, Greenland and Australia to provide ground-based early warning sites. The wing is also responsible for the C-21As operated on behalf of HQ AFSPC.
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<p>Another unit which began life as a Fighter-Bomber Wing, the 21st was activated in January 1953 at George AFB with the F-51 but was soon replaced by the F-86. The wing was transferred to USAFE to co-ordinate special weapons tactical air operations at Chambley AB, France with the F-86. The unit was redesignated the 21st Tactical Fighter Wing and moved to Misawa AB with PACAF in July 1958, before inactivating in June 1960. The designation was changed to the 21st Composite Wing and activated by Alaskan Air Command (AAC) at Elmendorf AFB in July 1966 with a variety of types including the C-118, C-124, C-130, F-4, F-102, H-21 and T-33. Squadrons from Elmendorf won the Hughes Achievement Trophy for excellence in air defense in 1972 and 1977 while operating the F-4E. The unit converted to the F-15A commencing March 1982 and upgraded to the F-15C version in 1987. The F-15E was added during 1992. The wing was absorbed into PACAF when AAC was dissolved in August 1990. The unit changed designation to the 21st FW during September 1991, but was replaced by the 3rd Wing in December 1991 as the major unit at Elmendorf AFB. The wing was reactivated at Peterson AFB early in 1992 to replace the 1st Space Wing.
