and the 131st was re-equipped with the F-51H Mustang Very Long Range fighter. With its air defense mission, the 131st was redesignated as the 131st Fighter-Interceptor Squadron.Beginning on 1 March 1953, the 131st placed two F-51H fighters and five pilots on air defense "runway alert" from one hour before sunrise to one hour after sunset. The runway alert program was the first broad effort to integrate reserve forces into a major Air Force operational mission on a volunteer basis during peacetime. In 1954, the Mustangs were reaching the end of their service life, and the 131st entered the Jet Age when it received F-94A Starfire interceptors. After the Korean War, the Massachusetts Air Guard began to modernize and expand. On 1 May 1956 the 102d wing was redesignated as the 102d Air Defense Wing and the Guard units at Barnes were authorized to expand to a group level, and the 104th Fighter Group (Air Defense) was established, with the 131st becoming the group's flying squadron. Other squadrons assigned into the group were the 104th Material Squadron, 104th Air Base Squadron, and the 104th USAF Infirmary. The 104th, along with the 102d Fighter Group (Air Defense) at Logan Airport, Boston began attending annual training at Otis Air Force Base. Tactical Air Command The squadron's air defense mission ended on 10 November 1958 when the Massachusetts Air Guard and its units were reassigned to Tactical Air Command (TAC) and converted to F-86H Sabre fighter-bombers. During the 1950s and early 1960s, better training and equipment, and closer relations with the Air Force improved the readiness of the Massachusetts Air National Guard. 1961 Berlin Federalization During the summer of 1961, as the 1961 Berlin Crisis unfolded, the 131st Tactical Fighter Squadron was notified on 16 August of its pending federalization and call to active duty. On 1 October the 131st was federalized and assigned to the 102d Tactical Fighter Wing, which was federalized and placed on active duty at Otis Air Force Base. The mission of the 102d wing was to reinforce the United States Air Forces in Europe (USAFE) and deploy units to Phalsbourg-Bourscheid Air Base, France. In France, the units were to provide close air support and air interdiction to North Atlantic Treaty Organization (NATO) ground forces. This involved keeping its aircraft on 24/7 alert. Between 28 and 30 October, wing elements departed Otis AFB for Phalsbourg. The wing deployed 82 F-86H