The 131st Fighter Squadron is a unit of the Massachusetts Air National Guard 104th Fighter Wing located at Barnes Air National Guard Base, Westfield, Massachusetts. The 131st is equipped with the F-15C/D Eagle. History World War II The squadron was first established in August 1942 at Bellows Field, Hawaii Territory as the 333d Fighter Squadron. It was initially part of the air defense of Hawaii, equipped with P-39 Airacobras. It also served as a Replacement Training Unit (RTU) and flew reconnaissance patrols over Hawaii until late 1943. The 333d deployed to the Central Pacific as part of the Thirteenth Air Force island hopping campaign against Japanese in late 1943. It engaged in combat with the Japanese until April 1944, returning to Hawaii and being re-equipped and trained with long-range P-51 Mustangs. The squadron redeployed to the Western Pacific, and was stationed on Iwo Jima while the battle for the island was still ongoing and engaged in long-range B-29 Superfortress escort missions over Japan. It continued that mission until the end of hostilities in August 1945. The unit was reassigned to the Mariana Islands, as a Far East Air Forces fighter squadron, and was inactivated there in 1946. Massachusetts Air National Guard The wartime 333d Fighter Squadron was redesignated the 131st Fighter Squadron, and was allotted to the Massachusetts Air National Guard, on 24 May 1946. It was organized at Barnes Municipal Airport, Westfield, Massachusetts, and was extended federal recognition on 24 February 1947. The squadron was equipped with P-47D Thunderbolts and was assigned to the Massachusetts National Guard 102d Fighter Group. In 1950, the Massachusetts ANG converted to the wing-base (Hobson Plan) organization. As a result, the 67th Fighter Wing was withdrawn from the Air National Guard and inactivated on 31 October 1950. In its place, the 102d Fighter Group was assigned to the newly activated 102d Fighter Wing, however there was no change in mission to the 131st and it remained assigned to the 102d Fighter Group. Air Defense Mission The mission of the 131st Fighter Squadron was the air defense of Massachusetts. With the surprise invasion of South Korea on 25 June 1950, and the regular military's lack of readiness, most of the Air National Guard was federalized placed on active duty. The 131st was retained by the Commonwealth of Massachusetts to maintain the air defense mission. In 1951, the F-47s were retired to Davis-Monthan Air Force Base