1961-12-20 USA X-15 Flight by Neil Armstrong

A significant X-15 flight cover postmarked at Edwards Air Force Base with a machine cancel on December 20, 1961, and signed by Neil Armstrong (NASA research pilot). The cover commemorates Armstrong’s first successful flight of X-15 No. 3 (56-6672), following an aborted launch attempt the previous day.

On this historic flight, designated X-15 Flight 46 (3-1-2), Armstrong evaluated the newly rebuilt aircraft and its experimental MH-96 adaptive flight-control system, which he had helped develop. He reached an altitude of 81,000 feet and a speed of Mach 3.76, approximately 2,502 mph. The flight marked the first flight of the third X-15 and became an important milestone in Armstrong’s distinguished career as an experimental test pilot, less than eight years before he would command Apollo 11 and become the first person to walk on the Moon.