The 166th Air Refueling Squadron (166 ARS) is a unit of the Ohio Air National Guard 121st Air Refueling Wing located at Rickenbacker Air National Guard Base, Columbus, Ohio. Since 1993 the 166th has been equipped with ten KC-135R Stratotankers.

Prior to 1993, the unit was known as 166th Tactical Fighter Squadron (166 TFS), operating a variety of fighter and ground-attack aircraft including Republic F-84 Thunderjet, North American F-100 Super Sabre and LTV A-7 Corsair II.

The 364th Fighter Squadron was established at Hamilton Field, California in December 1942 and was part of the 357th Fighter Group.

Became part of the United States Air Forces in Europe army of occupation in Germany during 1945. Inactivated in Germany during August 1946.

The wartime 364th Fighter Squadron was re-designated as the 166th Fighter Squadron, and was allotted to the Ohio Air National Guard, on 24 May 1946. It was organized at Lockbourne Army Airfield, Columbus, Ohio, and was extended federal recognition on 10 November 1947 by the National Guard Bureau. The 166th Fighter Squadron was bestowed the lineage, history, honors, and colors of the 364th Fighter Squadron. The squadron was equipped with F-51D Mustangs and was assigned initially to the Illinois ANG 66th Fighter Wing, operationally gained by Continental Air Command. On 7 December 1947 the Ohio ANG 55th Fighter Wing, was federally recognized and the squadron was transferred.

With the formation and federal recognition of the Ohio ANG 121st Fighter Group at Lockbourne Field, near Columbus, the squadron was reassigned. The mission of the 166th Fighter Squadron was the air defense of Ohio. Parts were no problem and many of the maintenance personnel were World War II veterans so readiness was quite high and the planes were often much better maintained than their USAF counterparts. In some ways, the postwar Air National Guard was almost like a flying country club and a pilot could often show up at the field, check out an aircraft and go flying. However, the unit also had regular military exercises that kept up proficiency and in gunnery and bombing contests they would often score at least as well or better than active-duty USAF units, given the fact that most ANG pilots were World War II combat veterans.

In October 1948 the squadron exchanged its F-51Ds for F-51H Mustang very long range escort fighters that were suitable for long-range interception of unknown aircraft identified by Ground Control Interceptor radar stations, the 166th being one of the first ANG squadrons to receive the F-51H. In March 1950, the squadron entered the jet age with the receipt of Republic F-84C Thunderjets.

With the surprise invasion of South Korea on 25 June 1950, and the regular military's complete lack of readiness, most of the Air National Guard was called to active duty. The 166th Fighter Squadron was federalized on 10 February 1951 and assigned to the 122d Fighter-Interceptor Group of the Indiana Air National Guard of Air Defense Command as the 166th Fighter-Interceptor Squadron. The squadron initially remained at Lockbourne and flew air defense training missions.