Neil Armstrong and the Cutting Edge of Hypersonic Flight

From the program’s inception, Neil Armstrong was actively engaged in both the piloting and engineering aspects of the X-15. He flew the first mission using a new flow-direction sensor (ball nose) and the first flight with a self-adaptive flight control system. Collaborating closely with designers and engineers on the system’s development, he made seven flights in the X-15 between December 1960 and July 1962. During these missions, he reached a peak altitude of 207,500 feet in the X-15-3 and a top speed of 3,989 mph (Mach 5.74) in the X-15-1.