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'Echos' of Challenger found in report

WASHINGTON -- Lessons learned from the 1986 explosion of the space shuttle Challenger were "undone over time" by NASA managers long before the disintegration of its sister spacecraft Columbia in a fiery return to Earth in February.

Eighty-seven shuttle missions after Challenger, investigators are wondering why.

"It didn't get fixed last time," said Steven B. Wallace, a member of the Columbia Accident Investigation Board. "There has to be a different approach now."

The board, in its final report released Tuesday, found striking parallels between the Columbia and Challenger accidents. It said NASA must overcome its rigid culture of stifling dissent, discounting safety problems and worrying too much about flight schedules if it hopes to safely return the shuttle to flight.

"Despite all the post-Challenger changes at NASA and the agency's notable achievements since, the causes of the institutional failure responsible for Challenger have not been fixed," the board wrote, adding that unless the flaws are fixed, "the scene is set for another accident."

NASA officials have vigorously objected to comparisons between Challenger and Columbia, arguing that since the Challenger accident even lower-level employees have authority during preflight reviews to raise safety concerns that can halt a launch countdown.

One board member, Sheila Widnall, said Tuesday that she "wanted to make sure we were not the second report to be joined on a shelf, to be joined by a third report." Another board member, Maj. Gen. John Barry, found "echoes of Challenger."

With both shuttles, the board concluded, NASA managers became dangerously inured to lingering safety problems -- erosion of a crucial O-ring component in 1986 and shedding foam in 2003 -- and permitted flights that were fundamentally unsafe. Researchers describe the tendency to become increasingly comfortable with risks as the "normalization of deviance."

"NASA has quite a lot of work to do," said Diane Vaughan, a Boston College sociology professor who popularized the phrase in her 1997 book about the Challenger accident. "NASA has shown a surprising lack of awareness about how its organization really works. One wonders if they really have the skills to fix it."

In one of the few dramatic new disclosures in the board's report, a top shuttle manager, Linda Ham, confided in an e-mail before Columbia's breakup that NASA's rationale for allowing continued flights before resolving a problem with breakaway insulating foam was "lousy then and still is."

Yet she never sought to intervene and spiked a request for telescopes or spy satellites to capture images of possible damage to Columbia's wing.

The board compared that decision to NASA managers' decision to permit Challenger's launch in 1986 despite pointed concerns about erosion in an O-ring component.

"Neither problem was defined as a show-stopper," the board wrote.

The board determined that superheated gases penetrated protective wing panels on Columbia that had been loosened or pierced by insulating foam that broke off its external fuel tank 81 seconds after liftoff and smashed against the shuttle. Investigators believe searing re-entry temperatures up to 5,000 degrees melted key structures inside until Columbia tumbled out of control and broke apart at close to 13,000 miles per hour, killing its seven astronauts.

Challenger was destroyed 73 seconds after launch when a joint in one of its solid rocket boosters failed and hot gases caused a structural failure during liftoff that ended with the explosion of the shuttle's hydrogen fuel.

On the Net:

Columbia Accident Investigation Board: www.caib.us

NASA: www.nasa.gov