The 4713th Defense Systems Evaluation Squadron is an inactive United States Air Force unit. It was last assigned to the 21st Air Division at Westover Air Force Base, Massachusetts, where it was inactivated on 15 April 1974. The squadron was first organized as the 4713th Radar Evaluation Flight at Griffiss Air Force Base, New york in March 1954 and expanded to a squadron in 1958. It began flying Martin B-57 Canberra aircraft in 1959, and continued to do so in the role of testing air defense systems until inactivating,