Getting Ready to Try Again

By David Brand

For the first time since that winter day 29 months ago when the shuttle Challenger and its crew of seven disappeared in a sickening cloud of smoke and debris, signs of vitality were evident at Florida's Kennedy Space Center last week. To the cheers of hundreds of workers, the redesigned 85-ton orbiter Discovery was rolled into the 52-story Vehicle Assembly Building to be attached to the two solid-fuel rocket boosters and the external fuel tank. This week plans call for the entire structure to be moved, at a glacial pace, more than four miles to launching pad 39B and poised for launch in late August or September. "The test results look good. The hardware looks great," said Deputy Operations Director Robert Crippen. "We're in the countdown to launch."

NASA at last appears to have pulled itself together after last January's damning revelation that a special commission had charged NASA and its contractors with routinely criticizing or ignoring employees who spoke up about lax shuttle safety. Agency officials now insist that safety, and not a prescribed timetable, is its No. 1 priority. NASA knows it is fighting for its life. "If it's anything short of picture perfect, the shuttle program is going to be at an end," says John Pike, space-policy director for the Federation of American Scientists. "NASA will be chopped up into little pieces."

Thus the watchword at NASA these days is caution. More than 200 modifications have been made to the orbiter alone, and dozens of others to the rocket boosters and the fuel tank. Would-be whistle blowers are encouraged to / report problems anonymously right to the top. "The real challenge," says Richard Truly, NASA associate administrator for space flight, "is to make sure we don't strangle ourselves with being worried excessively about safety."

The agency's renewed interest in safety is due in part to a $5.2 million lawsuit filed last year by Sylvia Robins, a systems engineer at a subsidiary of Rockwell International, the shuttle's principal contractor, and Ria Solomon, a former worker at Unisys, a subcontractor. Both claimed they were victims of corporate retaliation for whistle blowing. Charges that there were serious lapses in safety, quality control and security have been substantiated in a two-month investigation by a House Science, Space and Technology subcommittee. It also found that in 1986 and 1987 NASA and its contractors may have cut corners in developing and reviewing vital flight computer software in order to keep the shuttle on schedule. Rockwell may not share NASA's improved attitude: the company continues to call such charges "untrue."

One major milestone in the shuttle's flight readiness will come in mid-July, when Discovery's three modified main engines will be fired in unison for the first time. A few days later will come the final test of a booster by Morton Thiokol, the builder. Some of the three synthetic-rubber O rings (increased from two on previous rockets) that seal the booster's joints will be purposely flawed to see how well the rings can prevent the kind of leakage that triggered the Challenger explosion. Based on the outcome of the tests, NASA will decide on a precise launch date.

Even as NASA worries about safety, it must take many calculated risks. In May, for example, agency officials had to make a decision about a potential danger if a flight had to be aborted shortly after lift-off. What would happen, asked NASA analysts, if one or more of the valves that allow the liquid fuels to flow from the external tank into the orbiter's main engines failed to shut after the tank was jettisoned? The thrust from leaking fuel, they feared, could cause the orbiter and tank to collide. Since the shuttle's computer is not programmed to identify which valves have failed, the astronauts would not know how to maneuver their craft out of danger. In the end, officials decided not to reprogram the computer. The reasons: it was unlikely that both an aborted flight and valve failures would occur at the same time, and an analysis showed that the orbiter and tank would in fact miss . each other by five to eight feet. That, says Shuttle Avionics Chief Jack Boykin, is not close enough to justify complex changes in computer programs.

If the Discovery mission is successful, the NASA schedule will then call for nine flights next year and another nine in 1990. One hitch: there may not be enough solid rocket fuel. The shortage, which will begin next year, is the result of a series of explosions in early May that destroyed a Nevada plant that produced about 50% of the nation's ammonium perchlorate. The compound constitutes about 70% of the solid fuel used in the shuttle boosters.

NASA's more immediate concern is proving that it can get Discovery safely into space and back again. Most Americans, who will be watching on launch day, are just as anxious as NASA to see the shuttle program back in orbit.

With reporting by Jay Peterzell/Washington and Richard Woodbury/Houston