559th Fighter-Escort Squadron, 559th Strategic Fighter Squadron and 559th Fighter-Day Squadron

Constituted 81 Bombardment Squadron (Light) on 20 Nov 1940. Activated on 15 Jan 1941. Redesignated: 81 Bombardment Squadron (Medium) on 30 Dec 1941; 81 Bombardment Squadron, Medium, on 9 Oct 1944. Inactivated on 22 Jan 1946. Redesignated 81 Bombardment Squadron, Light, on 29 Apr 1947. Activated on 19 May 1947. Inactivated on 10 Sep 1948. Redesignated 559 Fighter-Escort Squadron on 27 Oct 1950. Activated on 1 Nov 1950; 559 Strategic Fighter Squadron on 20 Jan 1953; 559 Fighter-Day Squadron on 1 Jul 1957. Inactivated on 8 Jan 1958.