Lineage. Constituted 9 Pursuit Squadron (Interceptor) on 20 Nov 1940. Activated on 15 Jan 1941. Redesignated: 9 Fighter Squadron on 15 May 1942; 9 Fighter Squadron, Twin Engine, on 25 Jan 1943; 9 Fighter Squadron, Single Engine, on 19 Feb 1944; 9 Fighter Squadron, Two Engine, on 6 Nov 1944; 9