yournamehere

Actually, the turbojet-powered Heinkel He-178 was flown in 1939 - 5 years before the ME-262.
(Sorry - I'm a WWII buff <i>and</i> an aviation buff)

To answer your question, I assume you mean in "level flight." If so - it was the F-100 Super Sabre (1953). It was flown by the same test pilot who "unofficially" broke the sound barrier mere minutes before Chuck Yeager "officially" did it in the X-1.

Who was he?

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