The 27th Fighter Squadron (27 FS) is a unit of the United States Air Force 1st Operations Group located at Joint Base Langley–Eustis, Virginia. The 27th is equipped with the F-22 Raptor. The 27th Fighter Squadron is the oldest active fighter squadron in the United States Air Force, with over 95 years of service to the nation. It was organized as the 21st (later 27th) Aero Squadron on 15 June 1917 at Kelly Field, Texas. The squadron deployed to France and fought on the Western Front during World War I as a pursuit squadron. It took part in the Champagne-Marne defensive; Aisne-Marne offensive; St. Mihiel offensive, and Meuse-Argonne offensive.