Hypersonic flight

Hypersonic flight is flight through the atmosphere below about 90km at speeds above Mach 5, a speed where dissociation of air begins to become significant and high heat loads exist.

History

The V-2 rocket, first used in World War II by Nazi Germany and later used by the United States in its early rocketry work, was the first manufactured object to achieve hypersonic flight. In February 1949, its upper stage reached a maximum speed of Mach 5 (3,836 miles per hour; 6138 kilometers per hour).^{[clarification needed]} The vehicle, however, burned on atmospheric re-entry, and only charred remnants were found. In April 1961, Russian Major Yuri Gagarin became the first human to travel at hypersonic speed, during the world's first piloted orbital flight. Soon after, in May 1961, Alan Shepard became the first American and second person to achieve hypersonic flight when his capsule reentered the atmosphere at a speed above Mach 5 at the end of his suborbital flight over the Atlantic Ocean.

In November, 1961, Air Force Major Robert White flew the X-15 research airplane at speeds over Mach 6.^[1]^[2]