NEW ORLEANS — A half dozen current and former inspectors at the Louisiana plant that built Columbia’s external fuel tank have told The Miami Herald that the equipment endured chronic problems with failed adhesion of the insulating foam — the very flaw that may have befallen the space shuttle or contributed to its collapse.
“Could it be safer? Of course it could,” said one. “I can tell you I would never go into space under the current system — not until it’s safer. There have been too many cutbacks.”
Their warnings echo those detailed in studies that cite failings with the space shuttle’s tank, foam and tiles. At least two NASA reports describe debris from the sprayed-on foam insulation as the largest source of potential damage to the shuttle’s life-saving heat armor.
“It is estimated that 90 percent of the Thermal Protection System damage on the orbiter’s ‘belly’ results from de-bonded Sprayed-On Foam Insulation during ascent,” the 1997 study summary says.
NASA, aware of such warnings, nevertheless believed the foam that shot off Columbia’s fuel tank 81 seconds into flight Jan. 16 was not serious enough to cripple the craft.
NASA relied on assessments by Boeing Co. and its own engineers that concluded a “safe return — even with significant tile damage.” Those reports — obtained by The Herald — did not take into account the more dire possibility that the debris struck the vulnerable leading edge of the wing.
Now NASA and an outside investigative panel are exploring whether the space agency badly miscalculated.
NASA has made clear — and made clear again Monday — that it has come to no definitive conclusions as to what caused Columbia to collapse in the sky Feb. 1, killing seven astronauts.
“Everything is on the table,” NASA Administrator Sean O’Keefe told reporters. “There is no favored theory.”
Yet from moments after the shuttle’s demise, investigators have focused close scrutiny on the nearly 3-pound chunk of foam that catapulted off the 154-foot external fuel tank and into Columbia’s life-saving thermal tiles.
Those tiles are meant to protect the shuttle and its passengers from heat reaching 3,000 degrees. NASA’s own analysis shows Columbia suffered escalating temperatures on its left side, where the debris could be seen thumping the shuttle. On Monday, NASA said it recovered part of Columbia’s left wing, the suspect section.
Inspectors at the Michoud Space Center plant in Louisiana, where contractor Lockheed Martin made the fuel tank, are raising questions about the role foam may have played in the disaster.
“They used to lose foam, sometimes in significant amounts, with every flight,” said one quality engineer who retired in 1997. “They would send teams out to walk up and down the beach after a launch to pick up foam that came off.
They were never able to resolve that issue.”
Several inspectors — interviewed independently — said cutbacks in the number of quality inspectors may be linked to escalating foam failures.
“NASA’s budget cuts have meant we lost inspectors,” said a supervisor who oversaw the construction of the external tank for years. “Some things used to have 100 percent inspections. We just got limited, and I think it is very unhealthy.”