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Thursday, August 04, 2005

'04 Report Faulted Application of Shuttle Foam - New York Times

'04 Report Faulted Application of Shuttle Foam - New York TimesAugust 4, 2005
'04 Report Faulted Application of Shuttle Foam
By JOHN SCHWARTZ

HOUSTON, Aug. 3 - An internal NASA report last December warned of deficiencies in the way insulating foam was being applied to sections of the fuel tank to be used on the shuttle Discovery's current mission.

The report was provided to The New York Times by a person outside the space agency who is part of an informal network of people concerned about shuttle safety, and it did not recommend against launching the Discovery. But it delivered a harsh critique of the quality control and practices at the Michoud Assembly Facility in New Orleans.

That plant, managed by a major space contractor, Lockheed Martin, had come under intense criticism after a foam accident at liftoff led to the loss of the shuttle Columbia and its crew of seven astronauts in 2003.

While the National Aeronautics and Space Administration spent two and a half years and some $200 million to address foam problems after the disaster, they resurfaced on July 26, when a piece of foam as much as 33 inches long broke from the tank two minutes after liftoff. Future shuttle flights have been suspended until the problems are resolved.

The December 2004 report, by Conley Perry, a retired NASA division chief for quality engineering at the Johnson Space Center here, said it was obvious that Lockheed's external tank engineers "did not do a thorough job" of identifying the quirks and variations that can occur when foam is applied by hand. And despite the space agency's insistence that it would not allow scheduling pressures to dictate a return to flight before it was safe, Mr. Perry wrote, its reluctance to re-evaluate the quality-control problems "stems from the 'schedule-first' attitude" of Lockheed Martin management.

According to the report, even after two years of effort to correct the foam debris problem, "there will continue to be a threat of critical debris generation."

"This variable could reasonably be eliminated," the report went on, "and yet it continues."

The 23-page document was initially sent to safety managers by e-mail and came to be distributed more broadly. The person who provided it to The Times did so on condition of anonymity, saying he had not been authorized to read it.

Mr. Perry declined to discuss the document when reached by telephone.

The report was also reviewed by the independent group that monitored the space agency's progress in improving safety. A spokesman for that group referred questions to NASA.

David Mould, the agency's assistant administrator for public affairs, said a point-by-point response to the report was prepared but could not be released at this time because the information fell under confidentiality rules of the export controls that govern space technology.

But Mr. Mould added: "NASA and its contractors have made a number of process and quality improvements in the manual application of foam on the external fuel tank which have resulted in substantially less debris coming off the tank at launch. But as we saw, we still have work to do with the foam."

He continued, "There are still issues that we need to address and we will do that."

Marion LaNasa Jr., a Lockheed Martin spokesman, said, "We will defer to NASA regarding specifics of the memo, but would strongly emphasize that safety and quality are the guiding forces behind our workmanship on the external tank."

A former director of the Johnson Space Center, George Abbey, said that he had seen the paper and that its conclusions were cause for concern.

"You would think that American industry could solve and fix this whole problem when you look at what they've done to develop the technology that's gone into the rest of the shuttle," Mr. Abbey said.

As they prepared for the shuttle fleet's return to orbit, officials said they expected to see no foam bits larger than 0.03 pounds fall off the new tanks during the launching. The foam that broke away two minutes into the Discovery's liftoff, narrowly missing the craft, weighed 0.9 pounds. At least three other pieces also exceeded NASA's safety limits.

The agency administrator, Michael D. Griffin, has appointed a "tiger team" of engineers to find the causes of the incident and ways to fix the problem.

Attention has focused on the manufacture of the tank and on the area where the largest piece of foam fell off, a long aerodynamic feature known as the protuberance air load ramp, or PAL ramp.

The agency had long recognized that the PAL ramp could be a source of foam debris. Like the part of the tank in the Columbia's last mission, known as the bipod arm ramp, the foam on the PAL ramp is applied by hand. Those areas have tended to lose more foam than the large surface areas of foam that are applied by machine. Although flight histories showed only two incidents of foam loss from that ramp, the last in the early 1980's, there were dozens of night launchings in which falling foam would have been missed.

After the loss of the Columbia, NASA considered removing or redesigning the PAL ramp. But agency officials said that no good alternatives emerged, and ultimately decided not to change it. Instead, the ramp would be examined through an internal scan that would not require cutting into the material, to look for the air pockets, or voids, that are the leading cause of foam shedding.

Agency officials have broadly admitted since then that this decision was a mistake. As Dr. Griffin said in a television interview on Sunday, "We goofed on that one."

Mr. Perry's report did not dispute the decision to fly the tank with the hand-applied foam. According to the document, "there is no credible information available to bring into question the existing areas that have been designated as 'use as is' foam areas."

The paper concluded: "Notwithstanding the concerns discussed herein, I am comfortable with the decisions made by the various groups that identified the areas that required redesign and those that can be flown 'as is.' "

According to the report, Tank 121, which would be put on the Discovery flight, was "ready to support the resumption of flight operations."

As a test engineer, Mr. Perry worked on the investigation of the Apollo launching pad fire that killed three astronauts in 1967, and he conducted the test in which NASA burned a mockup of the capsule.

He retired in 1993 but was called back in the aftermath of the Columbia accident by the space agency's return-to-flight office of safety and mission assurance and was asked to monitor the quality of the operation at Michoud.

Mr. Abbey, the former Johnson Space Center director, said he was not surprised that Mr. Perry would not call for long delays over the PAL ramp issue, even though his overall criticism was so strong.

"I think he was probably torn between his recognition of the urgency to fly again and his concern about the tank," Mr. Abbey said.

He added that the problem with foam and the tank had needlessly undercut the successes of the return-to-flight mission. "You've got a complex system that's working amazingly well," Mr. Abbey said. By contrast, there have been persistent problems with "this essentially passive element that doesn't do much more than hold the fuel" for the eight and a half minutes it takes to reach orbit.

"That's given the shuttle - a great system - a bad name," he said. "And that's not fair."

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