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The top American ace of all time, the U.S. Ace of Aces was Richard Ira Bong. He shot down 40 Japanese planes in the Pacific. Over the years, there's been a lot of ink spilled about the relative scores of German and American aces. 27 Americans shot down over 20 enemy planes.
The pilots of the United States Air Force were heavily outnumbered and flew an airplane that in many ways was inferior to the MiG-15s flown by their Communist adversaries. Nor could they pursue the MiGs into their sanctuaries beyond the Yalu River. Nonetheless, they built up an impressive combat record. They included old hands from World War Two like Gabby Gabreski, John Bolt, and Bud Mahurin; newcomers like Hal Fischer and Pete Fernandez; and future astronauts like John Glenn, Buzz Aldrin, and Wally Schirra. Forty American fighter pilots achieved the coveted status of ace in Korea.