Lineage. Constituted 18th Pursuit Squadron (Interceptor) on 22 Dec 1939. Activated on 1 Feb 1940. Redesignated: 18th Fighter Squadron on 15 May 1942; 18th Fighter Squadron, Single Engine, 20 Aug 1943; 18th Fighter Squadron, Two Engine, on 6 Mar 1945. Inactivated on 15 Aug 1946. Redesignated 18th