566th Air Defense Group

566th Air Defense Group
Cannon armed F-89 of the 84th FIS at Hamilton AFB
Active	1944-1945; 1952–1955
Country	United States
Branch	United States Air Force
Type	Fighter Interceptor
Role	Air Defense
Part of	Air Defense Command

The 566th Air Defense Group is a disbanded unit of the United States Air Force. Its last assignment was with the 28th Air Division at Hamilton Air Force Base, California where it was inactivated on 18 August 1955. The group was originally activated as a support unit for a combat group at the end of World War II but never deployed before it was inactivated in 1945.

The group was activated once again in 1952 to replace the support elements of the inactivating 78th Fighter-Interceptor Wing. A year later ADC established it as an operational headquarters for fighter-interceptor squadrons as well. It was replaced in 1955 when ADC transferred its mission, equipment, and personnel to the 78th Fighter Group in a project that replaced air defense groups commanding fighter squadrons with fighter groups with distinguished records during World War II.

The group was activated at Robins Field, Georgia toward the end of World War II as the 566th Air Service Group in 1944 and trained to support a single combat group. Its 984th Air Engineering Squadron would provide maintenance that was beyond the capability of the combat group, its 1004th Air Materiel Squadron would handle all supply matters, and its Headquarters & Base Services Squadron would provide other support. The group was inactivated before it could be deployed overseas. It was disbanded in 1948.

During the Cold War the group was reconstituted, redesignated as the 566th Air Base Group, and activated at Hamilton Air Force Base, California in 1952 in a major reorganization of Air Defense Command (ADC) responding to ADC's difficulty under the existing wing base organizational structure in deploying fighter squadrons to best advantage. It replaced the 78th Air Base Group as host unit for Hamilton. The 566th was assigned eight squadrons and one flight to perform its support responsibilities. The group also assumed responsibility to maintain aircraft stationed at Hamilton from the inactivating 78th Maintenance & Supply Group, while the operational elements of the 78th Fighter-Interceptor Wing were assigned to the 28th Air Division.