The Boeing Dyna-Soar X-20, designed to be a 35.5-foot-long piloted vehicle with a sharply swept delta 20.4-foot-span wing, was shaped remarkably like the space shuttles of today. Constructed of super alloys, with a graphite and zirconia composite nose cap, the X-20 after re-entry would have landed on a dry lakebed using three retractable struts.