The Aviationist on MSN

Going Hypersonic: A Look at the Record-setting X-15

An important part of data collection for the United States space program, the North American X-15 had astonishing performance ...
National Security Journal on MSN

The Mach 6.7 X-15 ‘Hypersonic Rocket Plane’ Has a Message for the U.S. Air Force

The X-15 was a rocket-powered research aircraft that pushed human flight to the edge of space and deep into the hypersonic regime. -Air-launched from a B-52, three X-15s flew 199 missions between 1959 ...