Columbia's final readings deciphered
Data analysis sheds new light on problems before breakup
MSNBC STAFF AND WIRE REPORTS
The final seconds of flight data from the space shuttle
Columbia, transmitted even after contact was lost with
Mission Control, indicate that the crew members were
likely aware they were in serious trouble, NBC News
reported Thursday.
FOR SEVERAL DAYS now, experts at NASA's Johnson Space
Center have been immersed in the highly complex process
of reconstructing 32 seconds of data that were recorded
by computers in White Sands, N.M., but not displayed on
the computer monitors in Mission Control.
The data represent the final transmissions from Columbia,
which broke up over Texas on Feb. 1, killing all seven
astronauts aboard. The remaining three shuttles of NASA's
fleet have been grounded during the investigation of the
tragedy.
Investigators have said Columbia's final readings,
transmitted as the shuttle was descending toward a
landing in Florida, were so corrupted that NASA's
communication system kept them from being displayed at
Mission Control. However, new analysis techniques have
been used to interpret some of the corrupted data, NBC
space analyst James Oberg reported.
Bits of the data show a leak in the shuttle's Reaction
Control System, said Oberg, citing sources within NASA's
shuttle program who did not wish to be identified. This
system controls a series of small thrusters that were
firing furiously in an attempt to stabilize the orbiter.
Oberg, a former Mission Control engineer, said other
readings indicate a pressure drop in the left wing's
hydraulic system.
Such a scenario would have set off audible alarms in the
crew compartment. The last readable part of the White
Sands data indicates that Columbia's autopilot was
still functioning, Oberg reported, which means the
onboard computers were still operating at that point.
The corrupted data, which is still being analyzed, show
no indication so far of any voice communication from the
crew in the final 32 seconds, he said. The data would
support the prevailing view that Columbia's troubles
began with a breach on the shuttle's left side, but they
do not pinpoint the cause of the failure.
FOCUS ON FOAM
One leading theory is that foam insulation from Columbia's
external fuel tank, or perhaps the heavier material
beneath, may have done enough damage during liftoff to
trigger the breach during re-entry 16 days later.
The insulation is applied at a Lockheed Martin plant in
New Orleans. More of the foam is applied about a month
before liftoff in several small areas of the tank
needing touchup at NASA's Kennedy Space Center in Florida.
The board in charge of investigating the Columbia accident
has visited both sites and is going back for a second,
harder look at the techniques -- and safeguards -- used.
"That is getting a good bit of attention by more than one
of the groups," said NASA's Steve Nesbitt, referring to
the board's three working groups. "A couple of the groups
are looking at the thermal protection on the tank in this
area, and some of them will be going back to see the
manufacturing facilities, to talk to the people involved.
So it is getting some special attention."
Nesbitt said the theories that focus on the left side of
Columbia -- where all the overheating and other problems
developed -- "will be getting the earliest attention."
TROUBLED HISTORY
Air Force Maj. Gen. John Barry said earlier this week
that he and other board members are reviewing NASA's
troubled history of foam coming off the so-called bipod
area, where a pair of struts holds the tank to the
upper belly of the shuttle.
That is the spot where a chunk of foam came off 81
seconds into Columbia's flight on Jan. 16; the debris
slammed into the left wing during launch. An
engineering analysis days later concluded that any
damage was minimal and posed no safety threat.
NASA officials said that finding was based, in part,
on the fact that previous foam impacts had not caused
severe damage.
Barry said that four previous shuttle flights had foam
falling from the bipod area: Challenger in 1983,
Columbia in 1990 and again in 1992, and Atlantis just
last October. A 10-year gap exists between those two
last flights, he pointed out, "so we've got some
backtracking to do to be able to look at the history
and make the analysis."
Last week, the board inspected Atlantis and its fuel
tank at Kennedy and a completely assembled fuel tank
at Michoud Assembly Facility in New Orleans that is
identical to the one used by Columbia on its doomed
flight. The Michoud tank has been impounded by the
board for testing.
NASA estimates that the chunk of broken foam was 2.67
pounds (1.2 kilograms) and 20 by 16 by 6 inches (50 by
40 by 15 centimeters). The weight would be more if ice
were attached, a possibility under consideration by
the board. The panel also is looking into whether the
underlayer may have broken off.
Barry said he has learned that the heavier premolded,
ablative material beneath the foam "really doesn't
serve a purpose." He asked workers whether moisture
could have accumulated there and loosened the
insulation.
"We're looking at that as maybe an option on why the
foam came off and why we've had some problems in that
area," he said.
At Michoud, polyurethane foam insulation is sprayed
robotically about an inch (2.5 centimeters) thick over
the entire 154-foot (47-meter) tank to prevent ice
buildup on the metal tank, which is filled with
super-cold liquid hydrogen and oxygen during the final
hours of the countdown. The foam also helps protect
the tank from engine and aerodynamic heating.
In some small hard-to-spray areas, workers at Michoud
handpack the gaps with foam. At Kennedy, more foam is
applied by hand in the area around the bipod and also
around the other attach points.
PRIOR DAMAGE DESCRIBED
Internal NASA reports obtained by The Associated Press
describe damage during some of the earlier shuttle
missions, caused by foam from the bipod area.
Columbia suffered damage to three insulating tiles
during a June 1992 liftoff when a large chunk of
foam from the bipod -- 26 by 10 inches (66 by 25
centimeters) -- fell off. After the mission, NASA
determined that the shuttle fleet had suffered an
unprecedented amount of serious tile damage over 18
preceding flights.
Investigators believe damage to those three tiles was
from foam or similar material because of the size and
depth of the damage. On the same mission at liftoff,
ice and other insulating foam caused a "significant
concentration" of damaging strikes to tiles near
Columbia's right landing gear compartment. The
shuttle returned safely from that mission.
The damage to Atlantis in October was not considered
significant, at the time, by NASA. The foam from the
bipod area hit the bottom of one of the two booster
rockets, officials said.
During a visit Thursday to Stennis Space Center in
Mississippi, NASA chief Sean O'Keefe told reporters
that the analysis into the possible problems from
the external fuel tank alone fills an entire room at
Michoud. Everything is under consideration, though,
he stressed.
"There is no favorite theory. There is no favorite
approach to this. There is no preferred cause,"
O'Keefe said. "There is nothing right now that would
be argued as the most likely condition that I've
seen yet, and that is also the view of the Columbia
accident investigation board, I am advised."
IN OTHER DEVELOPMENTS
Teams of trained wilderness firefighters will join the
search for remnants of Columbia in Texas, NASA said
Thursday. In all, up to 3,500 searchers will operate
from four camps between Dallas and the Texas-Louisiana
state line.
Thirty-five helicopters also were being used in the
search for Columbia's remnants along a 240-mile-long
path that runs from just south of Dallas to the Toledo
Bend Reservoir, which sits between Texas and Louisiana.
U.S. Navy personnel are managing the search in the
reservoir, using side-scanning sonar and supervising
seven dive teams.
Experts investigating sick animals in Texas report no
evidence linking the problems to Columbia debris.
Concerns were raised that some cattle and deer came in
contact with potentially toxic debris following the
breakup of the shuttle. The probe by government
veterinarians began Feb. 7 after three cows had
swelling of the tongue and head. Two cows died.
But tests found signs of pneumonia, with bacterial
complications. Texas animal health officials say a
third cow is recovering.
Mental health counselors on the ground have helped the
three-member crew aboard the international space station
deal with their grief following the Columbia disaster,
the crew's commander said Thursday.
"One thing we talked a little about is standard grief
responses and the types of emotion you might feel,"
American astronaut Kenneth Bowersox said during a
broadcast interview.
The space station crew, which also includes American
Donald Pettit and Russian Nikolai Budarin, has planned
sessions with the psychological support team on a
regular basis, Bowersox said.
[NBC News' Dan Molina, The Associated Press and Reuters
contributed to this report.]
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