X-15 aircraft and B-52 mothership in flight, 1960s. Footage of a B-52 mothership with an attached X-15 aircraft (under its right wing), in flight at high altitude. The X-15 was a rocket-powered research aircraft designed to fly at hypersonic speeds. Its powerful XLR99 rocket motor was fuelled with ammonia and liquid oxygen. Manufactured by North American Aviation, it was operated by the United States Air Force (USAF) and the National Aeronautics and Space Administration (NASA). Three X-15s flew a total of 199 missions between 1959 and 1968. The X-15 was carried into the air by one of two converted B-52 bombers and released at high altitude. The pilot then ignited the X-15's rocket motor for a flight lasting around 10 minutes. It was the first plane to reach the edge of outer space (the highest altitude attained was 107 kilometres), and set records for the fastest manned aircraft (7, 274 kilometres per hour, or Mach 6.72). Take-off was from Edwards Air Force Base, California, USA, with landings after successful flights taking place at nearby Rogers Dry Lake. |