It was reactivated in 1969 as the 66th Fighter Weapons Squadron, an advanced training unit for Wild Weasel tactics until inactivating in 1981.

The 66th focuses on the A-10 Thunderbolt II, with the climax of the course being the mission employment phase, a two-week staged battle over the Nevada Test and Training Range.

Formed as a P-40 Warhawk pursuit squadron in January 1941 as part of the Army Air Corps Northeast Defense Sector (later I Fighter Command) at Mitchel Field, New York.

Took part in the British Western Desert campaign, engaged in combat during the Battle of El Alamein and, as part of Ninth Air Force, supported the Commonwealth Eighth Army's drive across Egypt and Libya, escorting bombers and flying strafing and dive-bombing missions against airfields, communications, and troop concentrations until Axis defeat in Tunisia in May 1943.

The squadron supported the British Eighth Army's landing at Termoli and subsequent operations in Italy, being reassigned to Twelfth Air Force in August 1943.

It flew interdiction missions against railroads, communication targets, and motor vehicles behind enemy lines, providing a minimum of 48 fighter-bomber sorties per day.

Was reassigned to Oxnard AFB, California in 1957, but was never equipped or manned due to budgetary constraints, inactivated by Air Defense command, January 1958.

Reactivated by Tactical Air Command at Nellis AFB, Nevada in October 1969 Assumed the F-105C/D Thunderchief assets of the provisional 4537th Fighter Weapons Squadron, tail coded "WC".