The F-86 was the U.S. Air Force's first swept-wing jet aircraft and the first production aircraft to break the sound barrier at Mach 1. First flown on October 1, 1947, it set a world speed record in 1948. Originally designed as a high-altitude day fighter, it was redesigned into an all-weather interceptor and fighter-bomber. A total of 9,860 of all variant models were produced. The F-86F had an upgraded engine and a larger "6-3" wing without leading-edge slats. The F-86 first saw combat in the Korean War, where it engaged Russian MiG-15 fighter jets. By the end of hostilities, it had shot down 792 MiGs while losing only 76 Sabre jets, a victory ratio of 10 to 1. This F-86F aircraft, serial number 52-5513, was donated to the Air Force Armament Museum by General Cho Young Bock of the Republic of Korea Air Force. It depicts F-86F Sabre serial number 51-2910, flown by Captain Joseph McConnell, who achieved triple-ace status with 16 MiG-15 kills while stationed with the 39th Fighter Interceptor Squadron in Korea during the Korean Conflict. The 39th Fighter Interceptor Squadron was later designated the 39th Flight Test Squadron at Eglin Air Force Base and is now part of the 40th Test Squadron.