Charles Elwood Yeager was a United States Air Force officer, flying ace, and record-setting test pilot who in 1947 became the first pilot in history confirmed to have exceeded the speed of sound in level flight.
Yeager's career began in World War II as a private in the United States Army, assigned to the Army Air Forces in 1941. After serving as an aircraft mechanic, in September 1942, he entered enlisted pilot training and upon graduation was promoted to the rank of flight officer, later achieving most of his aerial victories as a P-51 Mustang fighter pilot on the Western Front, where he was credited with shooting down 11.5 enemy aircraft. On October 12, 1944, he attained "ace in a day" status, shooting down five enemy aircraft in one mission.
After the war, Yeager became a test pilot and flew many types of aircraft, including experimental rocket-powered aircraft for the National Advisory Committee for Aeronautics. Through the NACA program, he became the first human to officially break the sound barrier on October 14, 1947, when he flew the experimental Bell X-1 at Mach 1 at an altitude of 45,000 ft, for which he won both the Collier and Mackay trophies in 1948.