Hypersonics Before the Shuttle- Part of the NASA Monographs in Aerospace History, Number 18, June 2000
NASA Armstrong Fact Sheet- X-15 Hypersonic Research Program
The X-15, the Pilot and the Space Shuttle
SpaceX to Launch Secretive Robotic Spaceplane for US Air Force- Robin Seemangal
A clean, simple landing page with an embedded HTML5 audio player (and audio cards for Twitter and Facebook).
Paste this code to embed an HTML5 audio player with controls.
Useful if you want to create a direct download link, embed in your own player, post from another publishing engine, link to from Patreon, etc.'