Describes how the X15 Aircraft was designed and built by North American Aviation. Engineered to be the worlds fastest aircraft, the North American X15 was a hypersonic rocketpowered aircraft operated by the USAF and the National Aeronautics and Space Administration (NASA) as part of the Xplane experimental aerospace projects. The X15 set speed and altitude records in the 1960s, reaching the edge of outer space and returning with valuable data later used in aircraft design. As of September 2015, the X15 holds the official world record for the highest speed ever recorded by a manned, powered aircraft. It would ultimately reach a top speed of 4,520 miles per hour (7,274 km/h), or Mach 6.72.