Monday, December 29, 2003

The fate of a wing shaped by politics: "Fragments of Columbia were laid out on a vast concrete floor like broken bones on an autopsy table. … For weeks, wreckage poured into the isolated hangar at Florida's Kennedy Space Center—27 tractor-trailer loads in all delivered by Lone Star Trucking."

"A key to interpreting the debris in the hangar was Columbia's flight data recorder. … 620 sensors had actually recorded reliable data. Fortuitously, there were more working sensors on the left wing than anywhere else on the vehicle. They matched the timing of interruptions in the sensor readings with the physical locations of wires that fed data to the recorder. By reconstructing the sequence of burning wires, they could follow the heat through the left wing. The new data established the timing of the accident and, by inference, narrowed the location of the initial wing damage.

"Wing sensor V07P8074A—one of the first to fail during reentry—also had recorded an unusual spike in pressure 16 days earlier, only 81.9 seconds after liftoff, just about the moment a spinning block of foam hit the leading edge.

"The debris, too, pointed to the left wing. Searchers found 827 pieces of the wing. Looking for the sense in so much slag, technicians in the reconstruction hangar used a computer database to match fragments against the locations where they were found. The resulting map revealed that the left wing had disintegrated first, falling to Earth west of Nacogdoches in East Texas."

"Few remember why the shuttle had a delta wing in the first place, but Max Faget does. … As a leading architect of human spaceflight, Faget left his stamp on virtually every U.S. manned spacecraft. He led the team that designed the blunt-bodied Mercury and Gemini space capsules. He collaborated on the design of the Apollo moon capsule. His name is on patent documents for the space shuttle system.

"By 1969, NASA had 13 different concepts for a fully reusable shuttle on its drawing boards. Faget was the chief engineer at NASA's Manned Spacecraft Center. For a space shuttle, Faget had in mind a two-stage reusable rocket plane with enough cargo capacity to resupply a space station. His design featured short, straight wings like those of a DC-3 cargo plane and a true tail so the shuttle could maneuver under its own power like an airplane, instead of gliding heavily to the ground like Columbia.

"In those plans, Faget proposed that the shuttle minimize the fierce heat of reentry by descending with its nose pointed up at a much steeper angle than the spacecraft that NASA would eventually build. The craft's belly would act like the blunt body of the Mercury and Apollo capsules he designed, spreading the heat more evenly across the broad underside of the spacecraft, rather than concentrating it along the leading edges of the wings.

"In 1971, the purity of the shuttle's design collided with the reality of politics. President Richard M. Nixon informed the space agency that there would be no Mars missions, no space station, no nuclear rocket engines. The remaining moon missions were canceled not long after. Unless NASA officials could win the support of the Air Force, there would be no space shuttle either.

"That meant NASA had to make more room in the cargo bay for big spy satellites. It meant NASA had to build a broad delta wing for the craft to carry out maneuvers required for military missions. All that extra weight meant an even heavier heat-shield system. Among other things, the extra pounds made it harder to accommodate the weight of crew escape pods or a stronger, more heat-resistant crew compartment. 'The delta wing was really the price of the space shuttle,' Faget said."

"At NASA, the men and women who tended the space shuttles were no longer its inventors and innovators. They were by necessity curators of an operational museum piece. At least a quarter of NASA's scientists and engineers were expected to retire within five years. Already the people over 60 outnumbered those under 30 by nearly 3 to 1. 'People talk about the learning curve,' said physicist Paul Dimotakis of Caltech. 'Nobody talks about the forgetting curve.' When it came to Columbia, time had made a mockery of NASA's institutional memory.

"The space agency had millions of technical documents meant to capture the expertise of the thousands of engineers who had designed and built the space shuttle fleet. Over the years, there had been so many design changes and so little money to document them that thousands of shuttle blueprints appeared to describe a vehicle that no longer existed. When accident investigators sought out a report documenting details of the shuttle's design or performance, they often found only PowerPoint presentations.

"Without the knowledgeable voice of the engineers who had originally presented them, the slides were meaningless. The board's investigators soon coined a phrase for this new institutional amnesia. 'Death by PowerPoint.'"

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