That first flight of the X-15 took place in September, nineteen fifty-nine. But the story began in the nineteen forties with the X series of experimental aircraft.
The first plane ever to fly faster than the speed of sound was the X-1 in nineteen forty-seven. United States government agencies and America's airplane industry realized then that it was possible to build an even faster plane. It would reach hypersonic speeds -- five times the speed of sound.
The first proposal for this new research vehicle, the X-15, was made in nineteen fifty-four. The space agency, Air Force and Navy jointly supported the program. They wanted a plane that could test conditions for future flights into space.
The project moved quickly. The North American Aviation company won the competition to design and build the plane. The design would be part aircraft and part spacecraft. The company took less than four years to produce three X-15s.
The planes were not big. They were just fifteen meters long with wings less than seven meters across. They were designed to fly at speeds up to six thousand four hundred kilometers an hour. They were designed to reach heights of eighty kilometers. Their purpose was to explore some of the problems of manned flight, during short periods, in lower space. No one had ever done that before.
The X-15 project had four major goals. It would test flight conditions at the edge of Earth's atmosphere. It would leave the atmosphere briefly, then return, testing the effects of the extreme heat of re-entry. It would provide information on the controls needed in the near weightless environment of lower space. And it would answer a very important question: How would humans react to space flight?
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25