The 120th Fighter Squadron (120 FS) is a unit of the Colorado Air National Guard 140th Wing located at Buckley Air Force Base, Aurora, Colorado. The 120th is equipped with the F-16C/D Fighting Falcon. The squadron is a descendant organization of the World War I 120th Aero Squadron, established on 28 August 1917. It was reformed on 27 June 1923, as the 120th Observation Squadron, and is one of the 29 original National Guard Observation Squadrons of the United States Army National Guard formed before World War II.