This week in Edwards flight test history Published Dec. 8, 2016 412th Test Wing Public Affairs EDWARDS AIR FORCE BASE, Calif. -- On Dec. 5, 1963, U.S. Air Force pilot Maj. Bob Rushworth flew an X-15 to Mach 6.06 which, at the time, was the highest speed achieved by a winged aircraft. During his time with the program, Rushworth completed 34 X-15 flights, more than any other pilot.