HOUSTON -- Nearly three years before Columbia launched, NASA engineers listed a host of potentially risky problems with foam insulation applied to shuttle fuel tanks at Lockheed Martin's factory near New Orleans, agency records show.
A list of "high risk" items was circulated among tank program officials in February 2000, including manufacturing processes at the Michoud Assembly Facility. That's where investigators are now probing whether application flaws caused foam debris to break away from Columbia's tank.
NASA investigators have zeroed in on wing damage from foam debris as the cause of the Feb. 1 accident that destroyed the $2 billion shuttle and killed seven astronauts. Today, the Columbia Accident Investigation Board will unveil its "working hypothesis" of what caused the ship to disintegrate after hearing testimony from a string of NASA witnesses.
The agency's internal investigators are convinced the foam impact 82 seconds after liftoff dealt a fatal blow to Columbia's heat shield. It caused a breach through which hot gas flowed as the ship plummeted through Earth's atmosphere, they say. The board is expected to concur.
A NASA manager working closely with the internal investigation told Florida Today the space agency and the board are waiting on the results of air-cannon tests -- in which engineers shoot pieces of foam at protective material and judge the results -- as possible proof. Other evidence gathered thus far points to the foam strike. Some of the issues at the heart of the Columbia investigation appeared on that 2000 list of "high risk" concerns. The list was compiled by external tank program officials at the Marshall Space Flight Center in Hunstville, Ala. The concerns included:
Foam coming off the tank because of improper application; deficiencies in the materials used; degradation during its transport to the Cape; the loading of supercold fuels; and the violent ride to space. Florida Today reported earlier this year that foam came off the tank on at least 71 flights to date, but NASA did not consider the resulting damage to the heat shield a safety issue.
Requirements and specifications not being followed in testing and manufacturing of the external tank.
Loss of institutional knowledge and experience at NASA and the Michoud plant because of "lots of old-timers retiring or taking buyouts" as the shuttle program reduced its workforce throughout the latter half of the 1990s.
NASA's limited insight into changes vendors had made with materials used in making the tanks.
Environmental requirements requiring removal of freon from the process for spraying the foam insulation onto the tank. NASA has said that the freon-free application method resulted in foam that initially did not adhere to the tank as well, but changes were later made to strengthen the bond of the environmentally friendly foam.
June Malone, a NASA spokeswoman at Marshall Space Flight Center, said she could not comment on the documents because she did not know the context in which the high risk list was created. She said she submitted questions to NASA managers who could explain the document, but would not get answers until Tuesday. Lockheed spokesman Marion LeNasa questioned the context too.
"I don't know what context those comments were issued in," LeNasa said. He and Malone both said it would be important to know who was asking the team to list their concerns and why.
The 2000 document was created by former tank program manager Joe Lusk, who compiled the "high risk" items from suggestions submitted by others on the project. Everyone on the project was asked to list their top five concerns, Lusk said in a March 1, 2000, e-mail to colleagues, which was released under the Freedom of Information Act.
Another concern raised on the 2000 list was reduced workforce at Michoud trying to keep up with schedule demands.
"Too much work and not enough time to really get up to speed on areas of responsibility" was a notation on one of two 2000 memos listing the concerns.
Bruce Wright of New Orleans, a former Michoud quality control inspector who was laid off in September 2002, said he too was concerned about the reduced workforce. He said the number of processes and parts inspected by NASA and Lockheed quality control inspectors declined over the years along with the number of workers at the plant.
"It's a very complicated system," Wright said. "As we know now, the foam adhesion is quite important. It was mandated by NASA to reduce the number of personnel. So we had to find ways to cut down on inspection points because we did not have the people to do the job. So they picked the steps generally done by inspectors that they felt were foolproof and eliminated those as inspection points.
"I don't think we should have removed so many inspectors."
Published under license from FLORIDA TODAY. Copyright © 2003 FLORIDA TODAY. No portion of this material may be reproduced in any way without the written consent of FLORIDA TODAY.
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