Mitchell (1879-1936) was the renowned pioneer of U.S. air power and generally regarded as one of the most far-sighted military leaders of his age.
One of the most famous U.S. aviators of WWI, he commanded the largest concentration of aircraft in France in September 1918 – about 1,500 warplanes.
Mitchell is thought to have logged flight time in the Thomas Morse Scout. The B-25 Mitchell used by the Doolittle Raiders was named after Billy Mitchell in honor of his contribution to airpower.
Both of these examples are on display at the Yanks Air Museum.