Engineers To Fire Another Chunk Of Foam At Wing

Engineers investigating the demise of Columbia have one more crucial test to perform before the Columbia Accident Investigation Board (CAIB) writes its final report. Monday, they'll use a compressed-gas cannon to fire a 1.67 pound chunk of insulating foam at a shuttle wing panel where they think debris caused Columbia a fatal wound shortly after lift-off on January 16.

The wing element used in the test at the Southwest Research Institute in San Antonio (TX) will be completely made of a reinforced carbon composite taken from the shuttle Atlantis. It's the same material and configuration that investigators believe was struck by foam from the external fuel tank 82 seconds after Columbia launched. Members of the CAIB believe the foam breached the wing. When Columbia re-entered the atmosphere two weeks later, investigators theorize the breach allowed super-heated atmospheric gases to enter the wing structure, beginning a chain of events that led to the shuttle's disintegration over the skies of East Texas. All seven crew members aboard were killed.

Already, similar tests have proven that the insulating foam can indeed cause cracks in the "carbon-carbon" wing panels. G. Scott Hubbard, director of NASA's Ames Research Center at Moffet Field (CA) and a CAIB member, says Monday's test will help the board decide if the January 16th foam impact was a "highly probable" or a "most likely" cause of the Columbia disaster, according to New York Newsday.

NASA's Not Waiting

Even in advance of what NASA Administrator Sean O'Keefe has warned will be a blistering report from the CAIB, NASA and its contractors are making changes they hope will address the board's findings. Last month, officials at the Marshall Space Flight Center in Huntsville (AL) sat down for a preliminary design review on a new external fuel tank that won't use insulating foam at all. Instead, the design uses two small electric heaters to prevent ice from forming on the fuel tank. This month, NASA is performing wind tunnel tests and other analyses of the new design.

"There could be some surprises that would make us stop and back up," said Neil Ott, deputy manager for the external fuel tank program at Marshall. Still, he's confident that the new design will be in use by the end of the year.

Problem Not Just On The Drawing Board

The CAIB is slated to release its report to the president, Congress and the American people before lawmakers leave Washington for their August recess. Adm. Harold Gehman (USN, Ret.), CAIB Chairman, has already said as much as half the Columbia report will deal with non-technical issues like NASA's management and corporate culture. "We will not tell NASA how to organize," Gehman said recently. "But we will tell them what needs to be done."

Gehman says the board has been reading up on what he calls "high reliability" organizations. He points to the FAA as an organization that doesn't wait for disaster, but learns of its mistakes from near-tragedies. "You learn as you go," CAIB Consultant Howard McCurdy told media sources. "The FAA learns from near misses. The FAA pays a lot of attention to near misses." Another CAIB consultant says "high reliability" organizations don't linger over their successes. Instead, they are continually on alert for the unexpected and the unwelcome, spotting such eventualities and trying to address them before they can impact the program at hand.

That mindset goes directly against the NASA mindset before the Columbia tragedy. On at least seven flights previous to STS-107, controllers and engineers virtually ignored chunks of insulating foam falling from the external tank and impacting the orbiter. NASA, in fact, eventually viewed such debris strikes as being within the parameters of normal flight.

A similar assumption is thought to have contributed to the 1986 Challenger disaster. Moments after launch, Challenger exploded. That accident was eventually attributed to erosion within the O-rings of the solid rocket boosters.

"What are the other things that are continuously sending you signals," Gehman asked in April. "I'd like to find some other things that are kind of strange looking, kind of funny looking and NASA says we're going to live with them."

"That's really been a bedeviling question," O'Keefe said recently. "It's the 'How do you diagnose the next thing around the corner?'" But he said the agency must find ways to sift through documentation and "not get bogged down with something that turns into this compendium of stuff that doesn't tell you anything."

FMI: www.caib.us