csua.org/u/8cc -> www.washingtonmonthly.com/features/2001/8004.easterbrook-fulltext.html
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. 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; 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. The main cause of delay is currently the shuttle's refractory tiles, which disperse the heat of reentry from the ship's nose and fuselage. Columbia must be fitted out with 33,000 of these tiles, each to be applied individually, each unique in shape. The inch-thick tiles, made of pyrolized carbon, are amazing in two respects. They can be several hundred degrees hot on one side while remaining cool to the touch on the other. They do not boil away like the ablative heat shieldings of capsules and modules; But they're also a bit of a letdown in another respect--they're so fragile you can hardly touch them without shattering them. Fixing them to the Columbia without breaking them is like trying to eat a bar of Bonomo Turkish Taffy without cracking it. Most of the technicians swarming over Columbia are trying to glue down tiles. The tiles break so often, and must be remolded so painstakingly, the installation rate is currently one tile per technician per week. All this mounting was supposed to be finished before Columbia left Rockwell's factory. The move also allows computer testing to proceed while the tiles are being mounted. This exercise may have been practical, but it was staggering in cost: $50 million extra to attach the tiles at the Cape, according to congressional sources. Some suspect the tile mounting is the least of Columbia's difficulties. If enough fall off, the shuttle may become unstable during landing, and thus un-pilotable. The worry runs deep enough that NASA investigated installing a crane assembly in Columbia so the crew could inspect and repair damaged tiles in space. Former Apollo astronaut Richard Cooper doubts the computers know what they're meeping about. Many of the projections are based on the magnificent accuracy of the Apollo landings. Apollo went to the moon, came back, and dropped all its little manned modules into a target area about the size of Los Angeles International Airport. They were slightly asymmetrical and thus had a little lift for control, but basically they fell like well-aimed stones. The science of ballistics is much more precise and predictable than the art of flying. To assume that experience with one is the same as experience with the other is to confuse a slingshot with a seagull. The only way to find out about something as big and balky as Columbia, Cooper says, is to launch the thing and see what happens. Computers have never flown with the unpredictable combination of damaged tiles that a shuttle may experience. They've never been whacked by a sudden, nonprogrammed gust of jetstream wind. They've never flounced like a twig on the crazy rapids of "bias"--the bland physics term for unexplained variations in the earth's gravitational and magnetic fields. To find out if your ship can cope with them, you have to take it up there. One Year And Holding The people struggling with the tiles serve a useful function. They make the rest of the project look good by comparison. It's supposed to build a small rocket booster, the Inertial Upper Stage (IUS), to ride in the shuttle bay. IUS, will float away from the shuttle and fire satellites into the high altitudes that shuttles can't reach. It's based on conventional throw-away technology and should be the easiest part of the project, but it's two years behind schedule and $144 million over budget. Columbia is to be powered by the first large, high-performance "cryogenic" rocket engine, burning liquid hydrogen for fuel instead of kerosene. Cryogenie engines can achieve the impossible dream-combustion efficiency of 99 percent. But the shuttle's cryogenic engines have the annoying habit of blowing up. The failures, of course, are taking place on the test stand. During development, it's assumed that some engines will blow up; But the shuttle engines often start flaming under normal operational conditions. And then there was this embarrassing snag that made checking their reliability all but impossible. Although the engines must fire for 520 seconds dining a shuttle flight, Rockwell's test stand held only enough fuel for 300 seconds. For a time, engine progress looked so bleak that Congress convened a panel of National Academy of Science members to decide if the motors would ever work. Just after the engineers managed to get single engines to fire properly for the full duration, for instance, they tried to fire three simultaneously, as would be required during a launch. Meanwhile, down at the Johnson Space enter in Houston, astronaut preparation was months behind even the short-pole schedule. Computer-simulators, used to stage mock failures in the flight trainer, weren't working. This was a triumph of accurate simulation, but otherwise not amusing. Despite these problems--which have been widely discussed in the trade press since as early as 1977-NASA made routine announcements that a launch was right around the corner. A cluster of three shuttle engines had just caught fire at NASA's test stand, a scant nine seconds into a test. The partially finished Columbia was mounted on the back of its 747 ferry plane for the flight to Cape Kennedy. The instant the 747 nosed off the field, Columbia began to rattle itself to pieces. The big jet hastily banked back to the field and rolled to a stop. So on a fine morning m March 1979 with engines blowing up, pilots playing parcheesi to pass the time, Columbia melting like an icicle in routine flight NASA announced that the first shuttle launch would be December 1979. History will record that there were no rolled eyes in Congress, no catcalls and guffaws at press conferences, no panic on the floor at Lloyd's of London. If it turns out they work, they will take their rightful place among the premier achievements of modern engineering (see "Because Out There is There" on page 49). Problems involving tiles continue, with residual doubt about "whether they can be relied on at all," according to the General Accounting Office. The good part is that Congress throws you money, hoping you will come out. Until recently, the shuttle program had an admirable record for cost control. Budgets were drawn as if redesigns would never be needed, as if no contingencies would arise, as if 520-second engine tests could be conducted with 300-second tanks. Of course, NASA planners knew everything would not work the first time. In a complex technological project, very little works at first; But to help the shuttle win budget approval, NASA estimated costs as if there would be no problems, according to Dan Cassidy of the House subcommittee that oversees space projects. To be "success-oriented," NASA decided to test shuttle components only after assembling them together, instead of individually as had been the case with all previous spacecraft. But if it didn't, the damn thing had to be torn down and tested from scratch. In 1979 NASA asked for, and got, a $220 million supplemental appropriation for Columbia. This January it asked for still another $300 million extra. Money is also being shifted from other NASA projects, mainly planetary probes that are interesting but lack immediacy, and from construction of the other three shuttles, into patching Columbia. By the time all four shuttles are built, the bill for development and manufacture will come to $13 billion, GAO estimates. The promised $5 billion inflates to about $8 billion today. And NASA w...
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