The 108th Air Refueling Squadron (108 ARS) is a unit of the Illinois Air National Guard 126th Air Refueling Wing located at Scott Air Force Base, Belleville, Illinois. The 108th is equipped with the KC-135R Stratotanker. The squadron is a descendant organization of the World War I 108th Aero Squadron, established on 27 August 1917. It was reformed on 1 July 1927, as the 108th 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.