October 3

October 3, 1967 - United States Air Force test pilot William Knight piloted his X-15 to a speed of 4,520 miles per hours (Mach 6.72), setting a speed record for a manned aircraft that still stands today. While this was a remarkable feat, the mission did not achieve its intended goal of going fast enough to create 1.21 jiggawatts of energy, the amount necessary to send the X-15 back in time.