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
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
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."