X-15 Flight 3-65-97, also known as X-15 Flight 191 (due to being the 191st free flight of the X-15), was a sub-orbital spaceflight of the North American X-15 experimental spaceplane, carrying seven experiments to an actual peak altitude of 266,000 feet, above NASA's definition of the start of space at 50 miles, but below the Krmn line. It took place on November 15, 1967, and was piloted by Michael J. Adams. It ended in tragedy when the aircraft broke apart minutes after launch due to technical difficulties, killing the pilot and destroying the plane.



The North American X-15 is a hypersonic rocket-powered aircraft. It was operated by the United States Air Force and the National Aeronautics and Space Administration as part of the X-plane series of experimental aircraft. The X-15 set speed and altitude records in the 1960s, reaching the edge of outer space and returning with valuable data used in aircraft and spacecraft design. The X-15's highest speed, 4,520 miles per hour (7,274 km/h; 2,021 m/s), was achieved on 3 October 1967, when William J. Knight flew at Mach 6.7 at an altitude of 102,100 feet (31,120 m), or 19.34 miles. This set the official world record for the highest speed ever recorded by a crewed, powered aircraft, which remains unbroken.During the X-15 program, 12 pilots flew a combined 199 flights. Of these, 8 pilots flew a combined 13 flights which met the Air Force spaceflight criterion by exceeding the altitude of 50 miles (80 km), thus qualifying these pilots as being astronauts. The Air Force pilots qualified for military astronaut wings immediately, while the civilian pilots were eventually awarded NASA astronaut wings in 2005, 35 years after the last X-15 flight.