The 31st Test and Evaluation Squadron was Strategic Air Command's representative in the world of flight testing. The squadron was tasked with monitoring and participating in the initial operational test and evaluation (IOT&E) conducted for SAC at Edwards AFB, CA. An assignment to the 31st was a special activity MAJCOM assignment and the squadron reported directly to Headquarters SAC under the Deputy Chief of Staff/Plans. In 1987, with over 90 officers and 300 enlisted personnel, the 31st was the largest initial operational test and evaluation squadron in the Air Force. While squadron members belonged administratively to the 31st, they were operationally committed to their specific test programs.

The 31st TES took over the IOT&E reins from SAC's 4200th Test and Evaluation Squadron on July 1, 1986. The 4200th was deactivated and the former 31st Bombardment Squadron (H) was reactivated and redesignated by CINCSAC direction. The reason behind this action was that the former CINCSAC and current Air Force Chief of Staff, Gen.Larry Welch felt that it was critical for members of each SAC unit to have a rich combat heritage with which it could identify.

The 31st Aero squadron of the Army Signal Corps was organized at Kelly Field, TX on June 26, 1917. This was to be the genesis of a long and prestigious history. The squadron served in France during World War I and it was there that the "skull and crossbones" were first placed upon a 31st Aero Squadron aircraft. The patch was officially approved in 1934 by the War Department. The squadron was reconstituted following the war and was subsequently deactivated and redesignated as a Bombardment Squadron on March 24, 1923. It remained on the inactive list until April 1, 1931 when the squadron was activated at March Field, CA. On February 1, 1938, the 31st left for Hickam Field, Hawaii and had all of its B-18s either damaged or destroyed during the December 7, 1941, Japanese attack on Pearl Harbor and Hickam Field. The squadron was soon back in the air with B-17s, tasked to support maritime bombing and surveillance missions. During 1943, the squadron converted to B-24s and continued bombing the Japanese into submission in the South Pacific. Serving throughout the Pacific after the war, the squadron was redesignated in October 1947 as the 31st Reconnaissance Squadron. The squadron flew B-29s and RB-29s, and was part of the Far Eastern Air Force. In late 1950, the 31st was moved back to the U.S. and placed under the 5th Strategic Recon Wing at Travis AFB, CA, where it began flying RB-36s in 1951. It converted completely to the B-36 by 1955 and was redesignated once again as the 31st Bombardment Squadron (H). The 31st accepted the Strategic Air Command's first B-52G in February 1959 and soon relocated to Beale AFB in early 1960. The squadron remained there until its deactivation in February 1963. Its proud lineage rested on the inactive list until July 1, 1966 when the squadron was reactivated at Edwards AFB, CA. The 31st task was to be the final inspection station before a strategic system was utilized. Its important mission was to make absolutely certain that SAC's new weapons systems were operationally suitable and effective.

During 1982, Detachment 3, 4200th TES was tasked with FB-111A Simulator Test programs and Modification and Software Management at Plattsburgh and Pease AFB. It was one of three detachments for the 4200th TES in SAC located at a bombardment wing. The unit had ten people assigned, yet was responsible for simulator software management as well as for monitoring and administering civilian contracts for simulator modifications. The current contractor at the time was McDonnell Douglas Electronics Company, which was installing the ALR-62 Electronic Countermeasures System. The modification took approximately one year to complete. The detachment had many on-going software update projects for improved simulator training capabilities.