The 123d Fighter Squadron (123d FS) is a unit of the Oregon Air National Guard 142d Fighter Wing located at Portland Air National Guard Base, Oregon. The 123d is equipped with the F-15C Eagle. The squadron is a descendant organization of the 123d Observation Squadron formed on 30 July 1940. It was activated on 18 April 1941. The squadron is one of the 29 original National Guard Observation Squadrons of the United States Army National Guard formed before World War II.