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NASA Team Believed Foam Could Not Damage Space Shuttle



 
 
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  #1  
Old July 23rd 03, 03:18 AM
Scott M. Kozel
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Default NASA Team Believed Foam Could Not Damage Space Shuttle

http://www.nytimes.com/2003/07/22/na...D-SHUT.html?hp

"NASA Team Believed Foam Could Not Damage Space Shuttle"
_New York Times_ - July 22, 2003

The team managing the final mission of the shuttle Columbia was so
convinced that foam insulation could not seriously damage the spacecraft
that they quickly dismissed the issue, transcripts of the team's
meetings released today by NASA show.

Linda Ham, the chairwoman of the Mission Management Team, cut off a NASA
engineering manager, Don L. McCormack Jr., at a meeting on Jan. 24 while
he was discussing the uncertainties and unknown risks from the piece of
foam that struck the shuttle some 80 seconds into the launch. Ms. Ham
repeatedly stressed in the following discussion that the foam posed "no
safety of flight" concern and "no issue for this mission."

The transcripts show an orderly and efficient process of dealing with
the many problems that crop up during any shuttle mission, and they were
filled with jargon and occasional inside jokes.

It also shows a team that was not fully on guard: despite NASA rules
that the management team meet on a daily basis during missions, the
group held only five meetings during the 16-day mission, taking off for
the long weekend of the Martin Luther King, Jr. holiday. An analysis by
National Aeronautics and Space Administration since the accident
determined that an attempted rescue with the shuttle Atlantis would have
had to be put into motion within the first four days of the mission.

"Nobody on this team believed that foam could hurt the orbiter, could
hurt the RCC at all," a person who has worked with the investigation
said, referring to the reinforced carbon carbon in Columbia's left wing.
"They had one fundamentally flawed understanding: that foam couldn't
harm RCC, and that colored everything else."

Mr. McCormack's presentation was based on an analysis from engineers at
the Boeing Corporation, which suggested that foam posed little risk to
the shuttle, despite the fact that the piece that struck the orbiter on
Jan. 16 was twice the size of any chunk that had ever struck the orbiter
before.

Earlier this month, when researchers investigating the accident fired a
comparable piece of foam at the spot on the leading edge of the left
wing that took the hit on Columbia, it blasted a hole 16 inches across
in the carbon composite panel, which is made from a brittle reinforced
carbon carbon..

NASA has scheduled a news briefing for reporters with Ms. Ham and other
members of the Mission Management Team later today. It will be the first
time that Ms. Ham has spoken publicly about the Columbia disaster.

The transcripts were released in response to requests by The New York
Times and other news organizations under the Freedom of Information Act.
They show that issues of foam come up in meetings as an item of far
lower priority than water leaks and temperature fluctuations aboard the
shuttle. The subject does not come up at all on the first meeting the
day after the launch, on Jan. 17, which took place before the foam
strike had been observed on launch films.

At the next meeting, on Jan. 21, Mr. McCormack described the incident,
saying, "as everyone knows, we took a hit on the somewhere on the left
wing leading edge." He said the impact was being studied for possible
damage.

Ms. Ham then discussed the fact that a similar incident of foam shedding
had occurred on a recent launch of the shuttle Atlantis and that no harm
had resulted. "The material properties and density of the foam wouldn't
do any damage," she said.

She then referred to the fact that NASA had decided to continue flying
the shuttles while the area that the foam came from, the bipod ramp,
could be redesigned. "`I hope we had good flight rationale the," she
said. "Really, I don't think there is much we can do," she said,
presumably referring to whether the decision to return keep flying was
valid or not.

"What I'm really interested in," she said, "is making sure our flight
rationale two flights ago was good."

In the Jan. 24 meeting, foam was discussed at greater length. Foam was
first brought up by Phil Englauf, a mission operations official, who
said he had sent a video clip of the foam impact to the astronauts so
that they could answer questions about it if it came up during a news
conference that day. "We made it very clear to them, no concerns," he
said.

Later, Mr. McCormack discussed the analysis from Boeing and said that it
suggested that there was no "safety of flight" issue" The analysis
focused on tile, not leading-edge panels, and Mr. McCormack tried to
explain that there were several unanswered questions that could mean
greater damage. "Obviously, there is a lot of uncertainty in all this in
terms of the size of the debris and where it hit and angle of
incidence," he began to say.

But Ms. Ham cut that line of discussion short, turning to a tile expert
in the room, Calvin Schomburg, and asking questions that seemed to
include the preferred answer. "Same thing that you told me about the
other day in my office; we've seen pieces of this size before, haven't
we?" she asked.

In fact, the piece was twice the size of any other chunk of foam
observed on previous missions. But the tenor of the meeting is one that
squelched concerns, the person working with the investigation said.

The Jan. 27 meeting took up the foam issue almost as a footnote, as an
engineer described further analysis of what might have happened if the
foam hit an area closer to the wheel well.

"There is no predicted burn-through and no safety of flight issue," the
engineer said.

"A non-issue?" Ms. Ham asked.

"Yeah, possibly," the engineer replied.

Foam did not come up at all at the final meeting of the team on Jan. 30.

[end of article]
  #2  
Old July 23rd 03, 03:56 PM
Doug Ellison
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Default NASA Team Believed Foam Could Not Damage Space Shuttle


"An analysis by
National Aeronautics and Space Administration since the accident
determined that an attempted rescue with the shuttle Atlantis would have
had to be put into motion within the first four days of the mission.



Anyone know the specific details of how such a rescue could occur?

Spacewalk two at a time from one vehicle to the other - with one of the two
spacewalking back with the empty suit of the first walk? seven times?

Doug


  #3  
Old July 23rd 03, 04:49 PM
Doug Ellison
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Default NASA Team Believed Foam Could Not Damage Space Shuttle


"Herb Schaltegger" wrote in message
...
In article ,
"Doug Ellison" wrote:

"An analysis by
National Aeronautics and Space Administration since the accident
determined that an attempted rescue with the shuttle Atlantis would

have
had to be put into motion within the first four days of the mission.



Anyone know the specific details of how such a rescue could occur?

Spacewalk two at a time from one vehicle to the other - with one of the

two
spacewalking back with the empty suit of the first walk? seven times?

Doug



I think the premise of the various rescue scenarios discussed by the
CAIB would have had Atlantis launching with five additional EVA suits in
addition to the two normally carried on each flight. Combined with the
two already aboard Columbia for contingency EVAs, this would have
allowed two Atlantis EVA crew to ferry over the seven Columbia
astronauts. I know I've read this somewhere recently in the last few
weeks but I don't have a link handy at the moment.


two onboard columbia - 5 on the ground - how many of these things are there
and could the other 5 be checked out and ready-for-flight checked quick
enough?

Doug


  #4  
Old July 23rd 03, 05:17 PM
Herb Schaltegger
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Default NASA Team Believed Foam Could Not Damage Space Shuttle

In article ,
"Doug Ellison" wrote:

"Herb Schaltegger" wrote in message
...
In article ,
"Doug Ellison" wrote:

"An analysis by
National Aeronautics and Space Administration since the accident
determined that an attempted rescue with the shuttle Atlantis would

have
had to be put into motion within the first four days of the mission.


Anyone know the specific details of how such a rescue could occur?

Spacewalk two at a time from one vehicle to the other - with one of the

two
spacewalking back with the empty suit of the first walk? seven times?

Doug



I think the premise of the various rescue scenarios discussed by the
CAIB would have had Atlantis launching with five additional EVA suits in
addition to the two normally carried on each flight. Combined with the
two already aboard Columbia for contingency EVAs, this would have
allowed two Atlantis EVA crew to ferry over the seven Columbia
astronauts. I know I've read this somewhere recently in the last few
weeks but I don't have a link handy at the moment.


two onboard columbia - 5 on the ground - how many of these things are there
and could the other 5 be checked out and ready-for-flight checked quick
enough?

Doug



Yeah, I wondered about that, too, both when I read it the first time and
just as I was making my reply. I don't know what the current stock of
EVA suits is like, especially how many of each size components there are
(torso, legs, gloves, etc). However, given the exigencies of the
circumstances, I don't think exact fits for the five on Columbia who
lacked suits would be required. :-/

That said, I still would like to know what the general stock of suits is
like. Are we talking five or eight suits, total, or a dozen or more? I
noted that a NASA press release lately indicates that a new contract for
EVA suit processing was just let (I think it was for maintenance; I
don't know if it included any new production components). Anyone with
better info, please feel free to chime in.

--
Herb Schaltegger, Esq.
Chief Counsel, Human O-Ring Society
"I was promised flying cars! Where are the flying cars?!"
~ Avery Brooks
  #5  
Old July 23rd 03, 06:40 PM
jeff findley
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Default NASA Team Believed Foam Could Not Damage Space Shuttle

Herb Schaltegger writes:
Yeah, I wondered about that, too, both when I read it the first time and
just as I was making my reply. I don't know what the current stock of
EVA suits is like, especially how many of each size components there are
(torso, legs, gloves, etc). However, given the exigencies of the
circumstances, I don't think exact fits for the five on Columbia who
lacked suits would be required. :-/

That said, I still would like to know what the general stock of suits is
like. Are we talking five or eight suits, total, or a dozen or more? I
noted that a NASA press release lately indicates that a new contract for
EVA suit processing was just let (I think it was for maintenance; I
don't know if it included any new production components). Anyone with
better info, please feel free to chime in.


You get around these issues by doing multiple EVA's. One suit can be
used for multiple EVA's per shuttle/station mission. The first walk
to Columbia could have been used to deliver O2 tanks and CO2
scrubbers, so time would not have been as important of an issue as
safety during the subsequent EVAs.

Jeff
--
Remove "no" and "spam" from email address to reply.
If it says "This is not spam!", it's surely a lie.
  #6  
Old July 23rd 03, 07:19 PM
Herb Schaltegger
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Default NASA Team Believed Foam Could Not Damage Space Shuttle

In article ,
jeff findley wrote:

You get around these issues by doing multiple EVA's. One suit can be
used for multiple EVA's per shuttle/station mission. The first walk
to Columbia could have been used to deliver O2 tanks and CO2
scrubbers, so time would not have been as important of an issue as
safety during the subsequent EVAs.

Jeff


Well, IIUC, there are other issues involving shuttle EVAs that can't be
alleviated simply by ferrying over O2 cyclinders and LiOH cannisters.
For one thing, the shuttle airlock can only fit three people (and I
think that's only been done on one EVA years ago - the usual is two).
That issue may or may not be significant in light of the next issue,
which is this: the EVA suits aren't charged with cabin air, they are
charged by the shuttle ECLSS high-pressure 02. Also, the shuttle ECLSS
pressurizes the airlock (I think) rather than the airlock being
pressurized by a simple vent/pressure equalization valve from the
orbiter mid-deck. Either way, the number of airlock cycles you can go
through is limited and you run the risk of mechanical failures each time
you cycle the lock.

I would think, all things considered, that you'd probably want to ferry
over as many people per EVA as possible. It limits the number of
airlock cycles necessary, reduces the amount of time the orbiters must
spend in close, station-keeping proximity and gives you the most
operational flexibility in planning the return of the rescue mission.

--
Herb Schaltegger, Esq.
Chief Counsel, Human O-Ring Society
"I was promised flying cars! Where are the flying cars?!"
~ Avery Brooks
  #8  
Old July 24th 03, 05:19 AM
Jorge R. Frank
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Default NASA Team Believed Foam Could Not Damage Space Shuttle

"Doug Ellison" wrote in
:


"An analysis by
National Aeronautics and Space Administration since the accident
determined that an attempted rescue with the shuttle Atlantis would
have had to be put into motion within the first four days of the
mission.



Anyone know the specific details of how such a rescue could occur?

Spacewalk two at a time from one vehicle to the other - with one of
the two spacewalking back with the empty suit of the first walk?
seven times?


Not quite.

Columbia had two suits, so Columbia and Atlantis would depress their
airlocks simo with two crewmembers inside. On the first transfer, one
Atlantis crewmember would transfer LiOH cans and two more suits to
Columbia, and return with the first two Columbia crewmembers. They would
doff their suits and leave them in the Atlantis airlock while the third and
fourth Columbia crewmembers repress the airlock, get into the new suits,
and depress. Repeat for rest of crew.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.
  #9  
Old July 24th 03, 07:51 PM
Chris Jones
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Default NASA Team Believed Foam Could Not Damage Space Shuttle

"Terrence Daniels" writes:

"Scott M. Kozel" wrote in message
...
"Nobody on this team believed that foam could hurt the orbiter, could
hurt the RCC at all," a person who has worked with the investigation
said, referring to the reinforced carbon carbon in Columbia's left wing.
"They had one fundamentally flawed understanding: that foam couldn't
harm RCC, and that colored everything else."


Right, and then - here's me trying to understand this from an engineering
point of view - the best thing to do at that meeting would have been to ask
the people making the presentation, "How exactly did you determine that
there's no possibility of damage?" with a follow-up about "What about the
RCC?" Am I right?


I think so.

And then if you found out that nobody had ever done any testing on the
RCC... You'd be making some pretty big assumptions on no real data, just a
"gut feeling."

Not trying to fry anybody, I just want to understand what the RIGHT thing to
do would have been in that situation.


I think these were the flaws in the process: although the foam was not
supposed to shed, it *did* shed, and this was accepted. Most of this
acceptance seems to have been the result of thinking "it hasn't hurt
yet, ergo it won't hurt in the future". The modelling which was done
was insufficient to adequately answer, with a high degree of confidence,
what kind of damage foam could cause. The CRATER modelling, which was
used to try to determine the damage the foam could cause to the tiles,
was based on extrapolating from micrometeorite studies which used
impactor sizes far outside the range which were resulting from the foam
shedding, and it's hard to see how there could be confidence in the
conclusions reached as a result of that. In fact, some of the studies
concluded that the the tiles would be completely penetrated, but for
some reason these were ignored and the conclusion was stated that some
tile would remain, sufficient to prevent loss of vehicle. The
post-flight testing apparently has shown that, in fact, the foam was
unlikely to have caused catastrophic damage to the tiles, but I think
NASA was lucky that their flawed reasoning (IMO) ended up giving a
correct result. They weren't so lucky when it came to the RCC: the
conclusion, as near as we can see based on no relevant testing, was that
foam couldn't do more that scratch the RCC leading edge of the wing.
This turned out, as we have seen, to be wildly off the mark.

So, in my opinion, the right thing to do would have been to take the
foam shedding more seriously, and take more stringent steps to ensure it
wouldn't shed, and not fly until you were reasonably certain it
wouldn't. Failing that (and I think this would have been a mistake),
you really have to understand what kind of debris events you're likely
to see, under what circumstances, and what kind of damage these might
cause. None of this was done, as near as we can tell. When *this*
event was seen, and questions were asked about what it might mean, the
rationale for conclusions should have been questioned, to ensure that
this wasn't a case of garbage in, garbage out, or wishful thinking.
Not all of these failings are the MMT's, the lower level meetings should
have been doing this.

  #10  
Old July 25th 03, 08:33 AM
Michael R. Grabois ... change $ to \s\
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Default NASA Team Believed Foam Could Not Damage Space Shuttle

On Wed, 23 Jul 2003 13:19:18 -0500, Herb Schaltegger
wrote:

In article ,
jeff findley wrote:

You get around these issues by doing multiple EVA's. One suit can be
used for multiple EVA's per shuttle/station mission. The first walk
to Columbia could have been used to deliver O2 tanks and CO2
scrubbers, so time would not have been as important of an issue as
safety during the subsequent EVAs.


You can't just bring over an O2 tank and plug it into the orbiter's Pressure
Control System (PCS). The O2 tanks are in the payload bay under the liner and
cannot be accessed except on the ground. If you bring something into the crew
compartment, you better make sure that you don't have a problem with the
high-pressure O2 in the bottles.

The CO2 scrubbers are Lithium Hydroxide (LiOH, pronounced "lie-oh") cannisters
that get plugged into specially made holes in the middeck floor. The cabin fans
blow air through the cans, which captuer the CO2 in the air.

Well, IIUC, there are other issues involving shuttle EVAs that can't be
alleviated simply by ferrying over O2 cyclinders and LiOH cannisters.
For one thing, the shuttle airlock can only fit three people (and I
think that's only been done on one EVA years ago - the usual is two).


Yes, only once before, on STS-49.

That issue may or may not be significant in light of the next issue,
which is this: the EVA suits aren't charged with cabin air, they are
charged by the shuttle ECLSS high-pressure 02.


They also use the shuttle's supply water to recharge the EMUs.

Also, the shuttle ECLSS
pressurizes the airlock (I think) rather than the airlock being
pressurized by a simple vent/pressure equalization valve from the
orbiter mid-deck. Either way, the number of airlock cycles you can go
through is limited and you run the risk of mechanical failures each time
you cycle the lock.


The airlock is pressurized through equalization valves in the middeck hatch,
and depressurized by venting the air in the airlock overboard
(non-recoverable). So for every airlock depress, you lose 150 cubic feet of air
overboard. Depressing the airlock is as simple as opening up the airlock
depress valve.

The limiting factor on the number of airlock cycles is the orbiter N2 supply,
not hardware; they've done 5 or 6 EVAs from the shuttle before while servicing
the HST.

Another complicating factor is the bends. The standard protocol is to go to
10.2 psi in the cabin the day before, followed by an in-suit prebreathe of O2.
That's not something you want to rush or even skip - getting the bends is not
fun. And that adds time to the whole transfer scenario, too.


I would think, all things considered, that you'd probably want to ferry
over as many people per EVA as possible. It limits the number of
airlock cycles necessary, reduces the amount of time the orbiters must
spend in close, station-keeping proximity and gives you the most
operational flexibility in planning the return of the rescue mission.


Atlantis EV1(A) is in the payload bay while EV2(A) goes over to Columbia. He
brings as many EMUs as they can carry (say four). EV1(A) enters Columbia's
airlock but doesn't take off his EMU (if you break the seal, you have to go
through the prebreathe protocol all over, and you're at risk for the bends).
Two Columbia crewmembers, EV1(C) and EV2(C), leave the crippled ship along with
EV1(A) back to Atlantis. They all enter Atlantis' airlock and EV1(C) and EV2(C)
take off their EMUs, while EV1(A) stays in his.

Meanwhile, EV2(A) goes to Columbia and picks up EV3(C), EV4(C), and EV5(C), who
have been in their suits for a while. They travel back to Atlantis while EV1(A)
goes back to Columbia with two empty suits.

EV1(A) picks up EV6(C) and EV7(C) from Columbia and brings them back to
Atlantis. Somewhere in there, depending on consumables aboard Columbia and
space in the airlock, they might be able to salvage some stuff and carry it
over (videos, experiment data, personal effects, etc.).

That looks like three depress/repress cycles on Columbia. Depends on what the
consumables situation would have been like.

 




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