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In the wake of last Thursday’s dramatic spacewalk from the international
space station — a walk cut short by a cooling problem in one of
the Russian spacesuits — new questions have surfaced about whether
the walk was really as safe as NASA insisted, and about how much information
about the suit problems was shared between the Russian and American partners.
There is now evidence that at the very beginning of the spacewalk, NASA
broke one its safety rules to prevent a delay. Further, there are suggestions
that specialists at Russia’s Mission Control Center were aware of
problems with the malfunctioning spacesuit hours before NASA and the rest
of the world learned of them.
These two issues appear to be entirely unrelated, but together they paint
a picture of a NASA still too ready to take risks, and of a Russian partner
still too unwilling to share their insights into safety issues.
"I'd be bemused if I wasn't concerned," a former member of the
Columbia Accident Investigation Board who asked not to be named told MSNBC.com.
Commenting on NASA's compliance with safety rules for extravehicular activity,
the former board member said: "NASA didn't convey any immediacy for
this EVA, I can only surmise that their proceeding and breaking their
own rule could be indicative of yet another perceived schedule pressure,
plus a continuing culture of waiving established rules."
Elaborate set of procedures -- Thursday's outing was the first-ever spacewalk
from the international space station that left no crew member aboard.
In recognition of the risks, NASA and the Russian Aviation and Space Agency
developed and tested an elaborate set of backup procedures. And to aid
in real-time decision-making, space experts in both countries drew up
flight rules that included a "Minimum Equipment List," defining
which hardware must be working in order for the spacewalk to proceed safely.
But now it appears that NASA officials went ahead and violated one of
the prime rules — the requirement for redundancy of remote monitoring
of breakdowns — to allow the spacewalk to proceed, even after breaking
the rule concerning what NASA calls “Caution and Warning”
capabilities.
NASA’s internal "On-Orbit Status Report" for Saturday
states: "When [Service Module] panel power was turned off during
EVA prep[aration]s, the PCS [portable computer system] laptop in the SM
was also deactivated, which was in violation of a flight rule and the
EVA-9 Minimum Equipment List.” This appears to have been the result
of an incorrect configuration radioed up from Earth, which led the crew
to connect the computer to a plug that they erroneously expected to remain
“hot” even when a nearby control panel was turned off.
The loss of the backup computer should have resulted in termination of
the spacewalk. As the document explained, “the flight rule requires
a minimum of two active PCS's attached to core data busses for Caution
& Warning support.” That is, there must be two separate ways
— a prime and a backup path — for automatically detected hazards
(such as a fire, leak or short circuit) to be announced to the station’s
telemetry system for notifying Earth.
Violation deemed acceptable -- But the rule was then deemed unnecessary.
“After coordinated evaluation/assessment of the situation by [Houston]
specialists, including the [Mission Management Team] Chair, the violation
was deemed acceptable, and EVA ops continued as planned,” the status
report explained.
The Mission Management Team is the group that oversees the operation of
the flight director and the team of flight controllers in the Mission
Control Center. It was in this kind of meeting during the flight of Columbia
last year that NASA officials decided potential hazards to that flight
could be disregarded.
After the Columbia investigation, NASA vowed to increase safety awareness
and institute closer oversight of future Mission Management Team deliberations.
In this case, one of the NASA officials explained privately to MSNBC.com
that “the consideration was that we had near-continuous [radio link],
so we could monitor and take action on Caution and Warning." But
NASA veterans told MSNBC.com that such a move should have been debated
during the development of the flight rules, not as an afterthought.
NASA’s status report ended its discussion of the incident with the
upbeat assertion that “the [computer] was successfully reactivated
following the spacewalk." But once the crew was back aboard the station,
the explicitly documented need for two computers was no longer in effect.
Cooling system problem -- The crew was back aboard the station after four
hours, instead of the planned six, due to a problem with the cooling system
in the spacesuit used by Russian cosmonaut Alexander Kaleri. It turned
out that one of the suit's coolant lines was kinked.
According to a NASA status report published the day after the outing,
“the walk was proceeding smoothly and problem-free for almost three
hours until Kaleri reported that drops of water were beginning to form
inside his helmet visor.”
But the same day, a different version appeared in the Russian news media.
A TV correspondent for Moscow’s Channel 1, Ivan Yevdokimenko, said
“the fact that Alexander Kaleri’s spacesuit was not cooling
off properly was spotted by Mission Control minutes after the spacewalk
began.”
NASA told MSNBC.com not to believe Yevdokimenko’s story.
“This account is wrong,” NASA spokesman Rob Navias said in
response to an e-mail query Friday morning. “We reported the cooling
issue immediately.”
It does seem that the cooling issue had not been brought to NASA’s
attention until Kaleri mentioned it on the air-to-ground radio link; only
at that point did NASA, at last aware, release the information.
What did they know, when did they know it? -- During a Friday afternoon
telephone press event, NASA’s lead spacewalk controller for the
mission, Michael Hembree, passed on what he had later learned about this
communications lapse. Russia's lead spacewalk expert in Moscow had conferred
with his own specialists after the spacewalk, and according to the account
Hembree had heard, “they were monitoring the outgoing temperatures
in the [cooling system] and they were higher than expected.”
As a result of these readings, they requested several times that Kaleri
be asked how he was feeling, but without explaining their reasons. When
the cosmonaut did not report being overheated, they took no further action.
Since the Russian side was in charge of the spacewalk and there seemed
to be nothing going wrong, NASA had not been informed of the worrisome
telemetry measurements.
When NASA's space station managers discussed the shortened spacewalk with
journalists in a Friday telephone briefing, they said they were puzzled
about when and how the coolant tube had kinked. Michael Suffredini, the
operations integration manager for the station program, could not explain
how the water cooling line could have started off in working order and
then gotten kinked halfway through the planned six-hour spacewalk.
On Monday, Russia's Itar-Tass news agency quoted spacesuit engineer Gennady
Schavelev as saying that the coolant hose "might have bent while
the cosmonaut was putting the spacesuit on."
Like the Russians, American space engineers who have talked privately
with MSNBC.com consider it much more likely it had been crimped from the
time Kaleri put the suit on. This would account for the anomalous temperatures
noted in Moscow early in the spacewalk — hours before Americans
were made aware of the problem.
Questions to be answered -- Suffredini asked for patience while the incident
is being investigated. “What crimped the hose is still a question
to be answered,” he stated. “We don’t know the mechanism
of how the line can get kinked, or get kinked intermittently. ... The
line is designed not to kink.”
Suffredini stressed that there was no health concern for the crew. “Never
was there any time that the crew was at risk,” he told reporters.
But by setting aside a newly endorsed flight rule, and by remaining uninformed
about the Russians' spacesuit concerns for almost three hours, the NASA
team may have run unnecessary — if slight — additional risks.
In hindsight, and in light of how those attitudes contributed to the shuttle
disaster a little more than a year ago, it looks like a little more soul-searching
of the NASA “safety culture” is called for.
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