Neil Armstrong with his X-15

Test pilot Neil Armstrong poses with X-15 aircraft #1 after a research flight in 1960. The X-15 was a rocket-powered aircraft 50 feet long with a wingspan of 22 feet. It was flown over a period of nearly 10 years, from June 1959 to October 1968, and set the world's unofficial speed and altitude records during that time.

Photo courtesy of the National Aeronautics and Space Administration. (The image number there is: E60-6286.)

See our biography of Neil Armstrong