Space: From the Washington Post, Board Urges Capability for In-Flight Repair: “The board investigating the Columbia disaster strongly urged NASA yesterday to develop a system to enable astronauts to inspect and repair ‘the widest practicable range’ of damage to shuttles while orbiting in space.”
I was calling the shuttle the “Space Porsche” back in 1983, as it spends much more time in the repair shop than NASA was willing to predict. Gregg Easterbrook’s 1980 article illustrated some problems that contributed to Columbia’s doomed reentry:
To truly grasp the challenge of building a space shuttle, think about its flight. The ship includes a 60-by-15-foot open space, narrow wings, and a large cabin where men must be provided that delicately slender range of temperatures and pressures they can endure. During ascent, the shuttle must withstand 3 Gs of stress–inertial drag equivalent to three times its own weight. While all five engines are screaming, there will be acoustic vibrations reaching 167 decibels, enough to kill an unprotected person. In orbit, the shuttle will drift through –250°F. vacuum, what engineers call the “cold soak.” It’s cold enough to embrittle and shatter most materials. During reentry, the ship’s skin goes from cold soak to 2,700°F., hot enough to transform many metals into Silly Putty. Then the shuttle must glide along, under control, at speeds up to Mach 25, three times faster than any other piloted aircraft has ever flown. After reentry, it cascades through the air without power; finally thunking down onto the runway at 220 m.p.h. The like-sized DC-9 lands, with power, at 130 m.p.h. Rockets are throwaway contraptions in part so that no one piece ever has to endure such a wild variety of conditions. The shuttle’s design goal is to take this nightmare ride 100 times.
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