NEWS: After Columbia Tragedy, NASA Considers Space Rescue

On Tue, 26 Aug 2003 21:34:36 GMT, "Steven D. Litvintchouk"
wrote:


Reuters

Aug. 26
— By Deborah Zabarenko

WASHINGTON (Reuters) - Could the Columbia disaster have been avoided?
After the fatal accident, NASA came up with a possible scenario to
rescue the crew with another shuttle.

If shuttle controllers knew by the seventh day of the mission there
was catastrophic damage to Columbia's left wing, they could have
rushed shuttle Atlantis into orbit and evacuated Columbia's crew
before the supply of breathable air ran out, investigators said in
their report on Tuesday.

We've been all thru this already, repeatedly.

Rushing Atlantis for launch contradicts the strong CAIB recommendations
that NASA shouldn't launch the shuttle if there is significant suspicion
that a major safety problem exists. Well guess what, the fact that
Columbia's left wing would have known to be damaged would have made them
just a little suspicious that a safety problem exists that could
jeopardize Atlantis too, don't you think?

With that problem unsolved at that point, they could have lost Atlantis
to exactly the same wing problem as they were losing Columbia.

And beyond that, rushing Atlantis for launch and insisting it launch no
matter what, in order to reach Columbia in time, could have caused other
safety problems to crop up.

Better to lose one shuttle and seven astronauts, then to lose two
shuttles and 11 astronauts.

The shuttle is an experimental vehicle, not some routine spaceliner.
And in experiments, you never risk any more people than you have to.



Here's what the CAIB report says about an Atlantis rescue mission:

Page 173



"...6.4 POSSIBILITY OF RESCUE OR REPAIR

To put the decisions made during the flight of STS-107 into
perspective, the Board asked NASA to determine if there were options
for the safe return of the STS-107 crew. In this study, NASA was to
assume that the extent of damage to the leading edge of the left wing
was determined by national imaging assets or by a spacewalk. NASA was
then asked to evaluate the possibility of:

1. Rescuing the STS-107 crew by launching Atlantis. Atlantis would be
hurried to the pad, launched, rendezvous with Columbia, and take on
Columbia's crew for a return. It was assumed that NASA would be
willing to expose Atlantis and its crew to the same possibility of
External Tank bipod foam loss that damaged Columbia.

2. Repairing damage to Columbia's wing on orbit. In the repair
scenario, astronauts would use onboard materials to rig a temporary
fix. Some of Columbia's cargo might be jettisoned and a different
re-entry profile would be flown to lessen heating on the left wing
leading edge. The crew would be prepared to bail out if the wing
structure was predicted to fail on landing.

In its study of these two options, NASA assumed the following
timeline. Following the debris strike discovery on Flight Day Two,
Mission Managers requested imagery by Flight Day Three. That imagery
was inconclusive, leading to a decision on Flight Day Four to perform
a spacewalk on Flight Day Five. That spacewalk revealed potentially
catastrophic damage. The crew was directed to begin conserving
consumables, such as oxygen and water, and Shuttle managers began
around-the-clock processing of Atlantis to prepare it for launch.
Shuttle managers pursued both the rescue and the repair options from
Flight Day Six to Flight Day 26, and on that day (February 10) decided
which one to abandon.The NASA team deemed this timeline realistic for
several reasons. First, the team determined that a spacewalk to
inspect the left wing could be easily accomplished. The team then
assessed how the crew could limit its use of consumables
to determine how long Columbia could stay in orbit. The limiting
consumable was the lithium hydroxide canisters, which scrub from the
cabin atmosphere the carbon dioxide the crew exhales. After consulting
with flight surgeons, the team concluded that by modifying crew
activity and sleep time carbon dioxide could be kept to acceptable
levels until Flight Day 30 (the morning of February 15). All other
consumables would last longer. Oxygen, the next most critical, would
require the crew to return on Flight Day 31.

Repairing Damage On Orbit

The repair option (see Figure 6.4-1), while logistically viable
using existing materials onboard Columbia, relied on so many
uncertainties that NASA rated this option “high risk.” To complete a
repair, the crew would perform a spacewalk to fill an assumed 6-inch
hole in an RCC panel with heavy metal tools, small pieces of titanium,
or other metal scavenged from the crew cabin. These heavy metals,
which would help protect the wing structure, would be held in place
during

re-entry by a water-filled bag that had turned into ice in the cold of
space. The ice and metal would help restore wing leading edge
geometry, preventing a turbulent airflow over the wing and therefore
keeping heating and burn-through levels low enough for the crew to
survive re-entry and bail out before landing. Because the NASA team
could not verify that the repairs would survive even a modified
re-entry, the rescue option had a considerably higher chance of
bringing Columbia's crew back alive.

Rescuing the STS-107 Crew with Atlantis

Accelerating the processing of Atlantis for early launch and
rendezvous with Columbia was by far the most complex task in the
rescue scenario. On Columbia's Flight Day Four, Atlantis was in the
Orbiter Processing Facility at Kennedy Space Center with its main
engines installed and only 41 days from its scheduled March 1 launch.
The Solid Rocket Boosters were already mated with the External Tank in
the Vehicle Assembly Building. By working three around-the-clock
shifts seven days a week, Atlantis could be readied for launch, with
no necessary testing skipped, by February 10. If launch processing and
countdown proceeded smoothly, this would provide a five-day window,
from February 10 to February 15, in which Atlantis could rendezvous
with Columbia before Columbia's consumables ran out. According
to records, the weather on these days allowed a launch. Atlantis would
be launched with a crew of four: a commander, pilot, and two
astronauts trained for spacewalks. In January, seven commanders, seven
pilots, and nine spacewalk-trained astronauts were available. During
the rendezvous on Atlantis's first day in orbit, the two Orbiters
would maneuver to face each other with their payload bay doors open
(see Figure 6.4-2). Suited Columbia crew members would then be
transferred to Atlantis via spacewalks. Atlantis would return with
four crew members on the flight deck and seven in the mid-deck.
Mission Control would then configure Columbia for a de-orbit burn that
would ditch the Orbiter in the Pacific Ocean, or would have the
Columbia crew take it to a higher orbit for a possible subsequent
repair mission if more thorough repairs could be developed.

This rescue was considered challenging but feasible. To succeed, it
required problem-free processing of Atlantis and a flawless launch
countdown. If Program managers had understood the threat that the
bipod foam strike posed and were able to unequivocally determine
before Flight Day Seven that there was potentially catastrophic damage
to the left wing, these repair and rescue plans would most likely have
been developed, and a rescue would have been conceivable. For a
detailed discussion of the rescue and repair options, see Appendix
D.13.

Findings:

F6.4-1 The repair option, while logistically viable using existing
materials onboard Columbia, relied on so many uncertainties that NASA
rated this option high risk.

F6.4-2 If Program managers were able to unequivocally determine before
Flight Day Seven that there was potentially catastrophic damage to the
left wing, accelerated processing of Atlantis might have provided a
window in which Atlantis could rendezvous with Columbia before
Columbia's limited consumables ran out...."









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