NASA: Gases Breached Shuttle Wing in 2000

Superheated gases breached the left wing of shuttle Atlantis during its fiery return to earth in hauntingly similar fashion to the demise of Columbia nearly three years later, according to internal NASA documents.

Unlike Columbia, Atlantis suffered no irreparable damage during the May 2000 episode and, after repairs, returned to flight just four months later. NASA ordered fleetwide changes in how employees install protective wing panels and sealant materials.

The small leak through a seam in Atlantis' wing during its return from the International Space Station was disclosed in documents sought by The Associated Press under the Freedom of Information Act. The mission commander was James Halsell, a shuttle veteran who is coordinating NASA's effort to return the shuttles to flight.

One of the seven Atlantis astronauts, Mary Ellen Weber, said NASA never told her about the breach, which was not discovered until the shuttle had landed.

"There are thousands and thousands of things that can go wrong, and the crew is very much aware this can happen," Weber said. "Certainly, when you learn about this, if it had progressed, it could have been much more dire."

Weber operated the robotic arm aboard Atlantis and flew aboard Discovery in July 1995. She said NASA may have reported the wing damage to other crew members. Attempts by AP to reach the other astronauts by telephone through family members and NASA offices in Houston and Washington were unsuccessful; one Atlantis crewman was a Russian cosmonaut and another has left NASA to return to the Air Force.

NASA spokesman James Hartsfield said crews and engineers generally participate in two months of meetings to discuss their experiences and spacecraft conditions. He could not say whether the shuttle's commander or pilot was told about the wing breach, which NASA blamed on incorrectly installed sealant material.

Some experts expressed surprise that superheated gases ever had leaked inside a shuttle's wing. Although protective wing panels have been found damaged, even cracked, the Columbia disaster was widely believed outside NASA to have been the first such breach.

"Very little information about the flaws of the tile system ever make it into the open literature, so those of us who work on this ... seldom hear much about serious problems such as this one," said Steven P. Schneider, an associate professor at Purdue University's Aerospace Sciences Lab. "I've never heard this sort of leak occurred."

NASA said it later determined Atlantis' exterior wing panels were not damaged by the overheating despite being discolored from the high temperatures. Aluminum structures inside the wing "looked outstanding," NASA said. Other parts immediately behind the wing panels were covered with a glassy material, apparently from melted insulating tile and other sealant material.

The space agency formally reported the damage to its Program Requirements Control Board, an internal safety oversight body, which ordered fleetwide improvements in the installation of sealant materials before Atlantis was allowed to launch for its mission in September 2000. Atlantis is expected to be the next shuttle into space when NASA is cleared to resume flights.

Weber, now an associate vice president at the University of Texas Southwestern Medical Center in Dallas, described Atlantis' return to Earth as mostly routine and remembered seeing an orange glow from hot gases dancing outside the shuttle windows.

Although damage inside Atlantis' left wing was detected post-flight, NASA worried about the shuttle's return even before the discovery.

During liftoff, a 6-inch chunk of ice had smashed against the back edge of the right wing; so experts deemed it prudent to adjust Atlantis' flight to rapidly cool its wings prior to the fiery trip through the atmosphere, NASA documents showed.

It was impossible to know whether this cooling technique, called a thermal conditioning maneuver, also helped minimize heat damage inside Atlantis' defective left wing. NASA later determined damage on the right wing was relatively minor.

The board investigating Columbia's Feb. 1 breakup determined that superheated gases penetrated protective wing panels that had been loosened by insulating foam that broke off its external fuel tank on liftoff and smashed against the shuttle. Investigators believe searing re-entry temperatures 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.

NASA did not consider ordering the thermal conditioning maneuver on Columbia because it believed such a move would have interfered with efforts to warm Columbia's landing gear tires for a safe landing.

NASA blamed the Atlantis damage on improper installation of a seal between two protective panels on the shuttle's left wing, "called a butterfly gap filler," at the Boeing Co. plant in Palmdale, Calif., during an overhaul of Atlantis in late 1997. The mistake went unnoticed during subsequent inspections because the part could not be seen without removing protective panels, NASA said.

Engineers found the damage on Atlantis while investigating the mystery of a partially melted insulating tile. Removing two protective wing panels nearby and peering inside the wing structure, they determined the dislodged seal had created "a substantial flow path," according to NASA's internal reports. The gap measured just over one-quarter inch, about the width of a paperclip or a No. 2 pencil.

The protective panels, insulators and other hardware inside the left wing "shows various signs of overheating," NASA reported. Photographs showed charred and scorched components, including parts made from titanium and inconel, two of the most heat-resistant materials on the shuttle. Titanium melts about 3,000 degrees; inconel melts about 2,550 degrees.

Investigators examining Columbia's breakup remain uncertain over the size of the gap that permitted hot gases to penetrate that shuttle's wing. But they believe it was as small as a one-inch slit running vertically up the wing for nearly 30 inches. In a test Monday, a chunk of foam blew open a dramatic 16-inch hole in parts of a mock-up of a shuttle wing.

Temperatures during a shuttle's return can climb to almost 3,000 degrees — nearly one-third as hot as the surface of the sun — along parts of the spacecraft, especially the leading edges of its wings. Damage there is considerably more likely to doom a shuttle than anywhere else. NASA requires immediate repairs when damage to the wing's protective panels exceeds four-hundredths of an inch, about the thickness of a dime.

Best summary so far, the only problem with the article is that it neglects to mention that the Vice President (Al - Wolfman - Gore) is in charge of the space program...

Did PC Science Cause Shuttle Disaster?

Friday, February 07, 2003
By Steven Milloy
http://www.foxnews.com/story/0,2933,77832,00.html

NASA is reconsidering whether tank foam debris caused the Columbia disaster. That’s quite a shift from days earlier when the foam was the "leading candidate" -- an explanation that quickly became embarrassing.

We may never know precisely what happened to Columbia, but one thing should be clear -- NASA should not be in charge of investigating itself.

A chunk of foam insulation broke off the external fuel tank during launch, perhaps damaging Columbia’s heat-protecting tiles. “We’re making the assumption that the external tank was the root cause of the accident,” said shuttle program manager Ron Dittemore in the immediate aftermath.

It seemed a very reasonable assumption based on Columbia’s history.

Until 1997, Columbia’s external fuel tanks were insulated with a Freon-based foam. Freon is a chlorofluorocarbon (CFC) supposedly linked with ozone depletion and phased out of widespread use under the international treaty known as the Montreal Protocol.

Despite that the Freon-based foam worked well and that an exemption from the CFC phase-out could have been obtained, NASA succumbed to political correctness. The agency substituted an allegedly more eco-friendly foam for the Freon-based foam.

PC-foam was an immediate problem.

The first mission with PC-foam resulted in 11 times more damaged thermal tiles on Columbia than the previous mission with the Freon-based foam.

A Dec. 23, 1997, diary entry on the NASA Web site reported: “308 hits were counted during the inspection, 132 were greater than 1-inch. Some of the hits measured 15 inches long, with depths measuring up to 1.5 inches. Considering that the depth of a tile is 2 inches, a 75 percent penetration depth had been reached.”

More than 100 tiles were damaged beyond repair, well over the normal count of 40. Flaking PC-foam was the chief suspect.

In 2001, the Environmental Protection Agency exempted NASA from the CFC phase-out. Even assuming for the sake of argument that widespread use of CFCs might significantly damage the ozone layer, the relatively small amount used by NASA would have no measurable impact. The bulk of CFC use, after all, was in consumer products such as air conditioners, refrigerators and aerosol cans.

But contrary to the exercise of common sense, NASA didn’t return to the safer Freon-based foam. Instead, NASA knowingly continued to risk tile damage -- and disaster -- with reformulated PC-foam.

This is obviously a potentially embarrassing situation for NASA.

In what smacks of an effort to avoid blame, NASA is now claiming the disintegration of Columbia has turned into a scientific mystery.

NASA says computer modeling fails to show how foam insulation striking the thermal tiles could do enough damage to cause catastrophe -- apparently ignoring that flaking foam substantially penetrated thermal tiles on an earlier flight.

NASA has even offered up the ultimate exculpatory theory -- that space junk or even a meteor could have hit the wing and damage the thermal tiles.

It’s certainly possible that a force majeure could have caused the disaster. But I’d like to see qualified independent experts come to that improbable conclusion.

Instead, NASA administrator Sean O’Keefe has activated the Space Shuttle Mishap Interagency Investigation Board. The board is a standing panel created by NASA in the mid-1990s. Its members are generals and other senior bureaucrats from the Department of Transportation -- except that no one from the National Transportation Safety Board is on the panel.

The appearance of independence is lacking. The board is a NASA creation. Its senior government bureaucrats may be reluctant to blame fellow senior bureaucrats. I also wonder whether the panel members personally possess the requisite technical expertise to investigate the accident.

The combination of NASA’s “lone meteor theory” and self-anointed commission strikes me as eerily similar to the Warren Commission and its controversial, if not dubious “lone gunman theory” for the assassination of President Kennedy.

Further, NASA previously dismantled its supposedly “independent” Aerospace Safety Advisory Panel after it questioned the agency’s long-term plans for safety.

NASA is not above pulling the wool over the public’s eyes for its own benefit.

Facing significant budget cuts in 1997, NASA produced the “Mars rock” -- a softball-sized meteorite found in Antarctica in 1984 containing complex organic molecules. Hoping to boost interest in the agency’s mission -- and its budget -- NASA boasted the rock was “evidence of primitive life on early Mars.”

Mars rock soon turned out to be Mars crock. Independent scientists arrived at a much more plausible Earth-bound explanation for the presence of the organic molecules.

NASA is an agency under pressure -- its mission is unclear and its budget demands are high. The last thing NASA needs is for its political correctness or other avoidable errors on the part of the agency to be the cause of the Columbia disaster.

The investigation into what happened to Columbia needs to be turned over to a truly independent and qualified commission -- and before the evidentiary trail starts to disappear.

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