|Columbia Accident Investigation Board Press Briefing
Wednesday, March 26, 2003
8701 Astronaut Boulevard
Cape Canaveral, Florida
Reporting: Keith L. Vincent, CSR
Esquire Deposition Services
ADM. GEHMAN: Good afternoon. We're pleased to be holding our press conference down here at KSC for a change. As is our usual practice, the board members have a few introductory comments to make. We will then be available to answer questions. The way we view these press conferences is this is an opportunity to dialogue. We aren't here to make news. We don't save up our news for Tuesdays or Wednesdays or whatever day of the week it is we try not to, anyway but this is an opportunity for you to dig a little deeper and delve a little more into what's been going on.
I am joined today by three board members representing three subpanels that we've broken ourselves into Admiral Steve Turcotte, Major General Ken Hess, and Dr. Steve Hubbard, each of whom will get an opportunity to speak.
By way of introduction, I think you are
probably aware that, unlike as I advertised last week,
my testimony before the Senate Commerce, Science and
Transportation Committee was canceled due to world
events. So I don't have anything to say about that.
As we have revealed this morning in our
discussions about debris, the way I would characterize
what I took away from that for you is that about
two thirds of the high-probability debris field grids have been searched and they're estimating it will take
about 30 days to finish the remaining part. On the
other hand, the detailed chemical/metallurgical
scientific analysis of the debris has really just
started. We really are just at the front edge of that.
So we've got a lot more to learn from there, and we're
just at the front end of that.
With that, I'll get out of the way; and
we'll just go right down the row here. First of all is
Admiral Turcotte, who is representing the group that
does the material and maintenance issues.
ADM. TURCOTTE: Good afternoon. I'd like
to give you a brief update today on the status of our
group, which includes Brigadier General Deal, Major
General John Barry, and myself.
General Deal spent much of last week
doing interviews at Michoud and looking at the process
of foam. We've all heard the term "follow the foam."
We're starting from way back, going back to when the
tanks were put together, and doing a thorough analysis
of what that tank looked like perhaps when it went
A first step to that was to take a tank that was of similar nature, last week, dissect it and see if we could find any abnormalities were process-related putting this into flight. We did find some anomalies. We found a couple of small voids that were in the bipod area where the insulation is sprayed and a couple of small voids that could probably cause and we're looking at that either a cryopumping effect or a breakage of some sort. That's still under analysis, and we're going to look at several other tanks to see if we find the same anomaly.
General Barry spent much of his time you've all heard on Day 2 of the shuttle that there's a radar signal that showed something drift away from the shuttle. We have, in the process to try and get a better idea of what that perhaps might have been, sent several samples of what-ifs to the Air Force laboratory at Wright Patterson Air Force Base to take a look at what kind of radar cross-section could that have been and try and marry that up. We have sent and I'll talk about it here in a second some carrier panels, some blankets, some tiles, other various items that could have, in any one of our theories on the left wing, separated from the aircraft. That analysis is ongoing, we've got some preliminary data back. It's pretty inconclusive at this point. More to follow on that as we engineer and develop that data.
Finally, I spent some time looking at the reinforced carbon-carbon material last week in Dallas
at the plant, and I'd like to focus my energy over here
to the left. If you could look, the first big piece
you see here is Panel No. 16. It is a reinforced
carbon-carbon panel. It's about a quarter of an inch
thick. It has a silicon carbide coating that carries
the heat, and in between it is 19 plies of impregnated
fabric that actually carries the dynamic load. So when
you refer to an RCC panel, that's what a real one looks
like. That came off the Enterprise. It's not flown
hardware, but it came off of the Enterprise.
At the end of it, if you could turn it
slightly and point out the T seal when we talk about
what the T seal looks like. The T seal is on the far
right hand side closest to you. If you could turn
around so that you can see where it actually splits and
joins and point to that, to the actual panel. Those
are what link each of the reinforced carbon-carbon
panels together on the shuttle.
ADM. GEHMAN: You can see why it's called
a T seal.
ADM. TURCOTTE: Absolutely. That's why
it's called a T seal. Now, what you don't see there
are some of the metal linkage in the hardware that you
may or may not have seen this morning from the public hearing. Now, that hardware is made out of Inconel
metal which, as we found out, comes apart at about
2450 degrees. A large part of the inside of those RCC
panels was covered with that linkage hardware.
Another two panels there. The very short
one, is a closeout panel. The bigger one is a closeout
panel that's from the top of the wing, and the smaller
one's from the bottom. Carrier panel. Closeout panel.
A number of different terminologies. But this is the
panel, if you can hold that up and show that in
relation to the RCC, where it attaches to the leading
edge of the wing. It's about like that. So that's
what's right between the blunt part of the wing and the
We're also looking at the processes. As
in the foam, was there perhaps a degradation in the
material. We're looking to go back to find out how old
these panels, how long they've been on the aircraft,
have they been inspected, and what quality perhaps were
they. Both in the foam and the RCC, non-destructive
evaluation is an ongoing issue that we're looking at
very heavily to ascertain the actual flight conditions
that the shuttle was in at the time that it took off.
That concludes my remarks.
ADM. GEHMAN: Thank you very much.
Major General Ken Hess.
GEN. HESS: Good afternoon. Over the
period of the time in the last week, Group 2, which is
myself and Steve Wallace, as well as Dr. Sally Ride,
have busied ourself doing many, many interviews, to
include going to Washington, D.C., last week to do some
senior NASA officials. Steve Wallace continues his
work toward return-to-flight issues as well as kind of
a new mission for him, and that's focusing the board's
recommendation process just a bit. Dr. Sally Ride has
keyed in on decision processes that were involved in
the key operational parts of this mission, to include
the much-reported DOD request for imagery as well as
the disposition of other STS foam events as they
affected the decision to fly STS 107.
I would encourage us all just to keep in
context the E-mails and a lot of the information that's
been said until we have a pretty complete story here
that will be reported, because the E-mails are just a
very small part of the overall picture that will be put
together by the group and recommended to the overall
board for some degree of decisions.
We're also busying ourselves now,
starting last week, taking a look at the safety
organization. Of course, the Rogers Commission indicted the safety organization within NASA as being
silent; and, of course, we're going to take a look at
the newly re-engineered safety organization and ask
ourselves questions about responsibility and
accountability to see what opinions we might form in
As Admiral Gehman has indicated, the
debris collection effort that we all heard about this
morning is coming into its probably final stages and we
will be bringing a briefing to the board through the
debris committee out there that recommends how we
actually will close that out and will be working with
NASA to determine the appropriate way and timing on
that closure effort.
Probably within the next week or ten
days, I expect that we will close out from our previous
deliberations all aspects of crew training and
performance as they relate to the mishap, as well as
certification issues on the crew itself.
That concludes my remarks.
MR. HUBBARD: I'm here representing
Group 3 this afternoon. That includes Jim Hallock,
Doug Osheroff, Roger Tetrault, Sheila Widnall, and
myself. We've continued to use all the data we can
collect from the telemetry, from the debris field, from other examinations of downlinked information to bound
the event in the orbiter, and we're on the verge now of
beginning to oversee some tests which we hope will
either confirm or exclude some of the conclusions that
you've been aware of.
This afternoon I'd like to report on
three different areas. First of all, I would like to
give you an update on the so-called OEX box. This is
the flight recorder-like device that was found;
secondly, talk a little bit about the analysis of the
visual data, where we're hoping to hone in even more on
where this external tank debris hit the leading edge;
and then finally talk about the tests of the foam
impact that are being prepared and will commence here
in about ten days.
So to start, let's examine the OEX
recorder. The million-dollar question, of course, is
what's on it. It arrived in overall good condition.
It's got 1-inch tape with 28 tracks on it. If you look
closely in the lower right-hand corner, you can see the
very end of the tape there, which had a crumpled and
wrinkled section about 10 to 15 inches long. Initial
testing that was done just yesterday shows there is no
data on this section. We believe this is actually a
good outcome. It indicates, we hope, that the data recording is back in the earlier part of the reel where
it is, relatively speaking, undamaged.
The timetable for this is that the box is
here at the Kennedy Space Center. They will duplicate
the good tape that's on that reel and send it back to
Johnson Space Center by Friday. That will be processed
over the weekend, and the data review will begin on
Monday the 31st.
We've looked into what is believed to be on this tape. If it is a perfect world, we will have 721 measurement sensor outputs. This covers the wings, the fuselage, and the vertical tail surfaces. Of particular interest are going to be 182 pressure measurements; 53 temperature measurements; and 447 loads, dynamics, and stress measurements. Among these will include a series of measurements, if we get all the data back, on the left wing strains, stresses and strains, temperatures and pressures.
Now, we have to note that this has been
through a very severe environment. We don't know if
the tape has been demagnetized. We don't know yet the
quality of the data on there. What I'm describing to
you is if it's a perfect outcome. We also have to note
that the wires from this box to the sensors pass
through the same wheel well area where other sensors went off line. So just wait and see over the next few
days what we find. If all the data were there that
I've described, of course, this would be a gold mine of
information that could lead us to a much, much better
understanding of what happened throughout the vehicle
and particularly on the left wing. It's expected that
if it was a normal mission, it would have about 30
minutes of data from ascent and, in a nominal mission,
an hour of entry data. Of course, no on-orbit data.
Now I'd like to turn to the work that's been done with the visual analysis of the external tank impact. I think you all know that there are two cameras that took pictures, one video and one film, of the debris-shedding event that occurred at 82 seconds. What the various visual analysis teams have been able to do, they have taken this data and taken the view from one angle, the back side, the view from the other angle, the front side of the orbiter at this time and constructed now a three-dimensional trajectory path. I think if you look here, you can see that path in red. It looks like a pipe and it begins very, very near the bipod ramp area lending further credence to the speculation that this was the origin of this event and carrying down to the leading edge there. I'll describe a little bit further in the next slide where the trajectory analysis says that it hit.
Now, imagine that this piece came off and
it's tumbling and spinning, coning, turning, and
therefore it's creating a footprint, an impact
footprint. This footprint is probably at least 2 feet
in diameter, perhaps 3 or more. It depends on exactly
how this sample or this piece of debris came down
through the flow field that couples with the vehicle as
If you take that information, a plotting
of each position frame by frame, and put a
2-foot-diameter impact ring around it, then you see
something like this. Imagine this impact footprint now
intersecting with the three-dimensional leading edge
here. It's the same kind of curved surface that you
see on the RCC panel over here. As you can see, the
area of impact begins somewhere around Panel 5, goes
through Panel 6, extends into Panel 7, then begins to
cover the tile acreage on the bottom of the wing and,
of course, moves very close to the main landing gear
This information, which is derived
directly from the visual frames both in the film from
one angle and the video from the other angle, leads us
directly into testing whether or not this impact could have been the initiating event for the tragedy that
followed. So let me go now to foam impact testing.
Oh, you can see here another picture of
how this footprint would have traveled across the
T seal and across the RCC Panel 6 and then moving into
what Admiral Turcotte described earlier as the closeout
panel area. This is what informs about where to go and
test to see what damage this could have created.
These tests will be conducted in four areas the main landing gear door tiles, the wing tiles, the carrier panel also known as the closeout panel that I showed you, and the reinforced carbon-carbon leading edge subsystem. Currently two sizes are being evaluated by the NASA team. Their test plan is one that will be brought forward to the group, first Group 3 of the board and then, if necessary, consideration by the entire board before the tests are initiated. They're looking at a 1- and a 2-pound mass traveling at about 500 miles per hour, 700 feet per second. One size would be 3 inches by 12 inches by 24 inches. That is the best current measurement from observing the debris that actually fell off the tank and hit the wing. The other is a size of about 6 inches by 14 inches by 24 inches, which is the size that was first evaluated during the mission. The angles will be close to simulate to the visual observations, on the order of 10 to 20 degrees, and the calibration tests will be conducted at Southwest Research Institute, using a gas-pressurized gun with an appropriate sized barrel.
Now, the size of this piece is being also determined by the size of the piece that fell off during STS 50. If this is the bipod ramp so this is an exact model of the foam you look at this black line. This black line indicates on STS 50 the size of the piece that fell off. It weighed about a pound, some 700-plus cubic inches. This is close to the calculated dimension from the visual observations. So a chunk like this may well have been what fell off and hit the leading edge.
Once all the analyses are concluded, a piece like this is what will be fired from this gun into the four kinds of samples that I described; and that's informed by the visual analysis done that says in this intersection you could have hit any one of these four types of materials tiles on the under side, tiles near the main landing gear door, a closeout panel, and, of course, the reinforced carbon leading edge.
I'll conclude now just by showing you one of the tests that was done in the calibration test.
Don't pay any attention to that white plume. It just
happened to be a cold morning with warm air. So this
is condensation. This shows the kind of calibrations
that have been done thus far with pieces of foam with
angles that are approximately those of the ones that
I'll just finish by saying that we will
continue to be challenged to match the tests and the
analysis with the observed events and that we will not
be able to conclude that we know the initiating event
that started this tragedy until our theories match the
facts. That's all.
ADM. GEHMAN: Thank you very much, panel
members. We're ready for questions.
A REPORTER: Florida Today. I would just
like to know where you are with the other element of
the imagery, the spectral analysis of the debris to try
to determine whether or not the makeup is only foam.
MR. HUBBARD: Well, there's two questions
embedded there. One is spectral analysis of any of the
visual data. We don't hold out at this point a great
deal of hope that this is going to yield anything. It
would be just fortuitous happenstance because of the
kind of data that we've got. There's groups within NASA that are looking at this; but, frankly, at this
point we'd be very surprised if we learned anything.
The other part of the question is what could be in here if something like this, indeed, was the impacting element besides just the foam. For that I will refer to the statement by Admiral Turcotte that when they cut open the External Tank 120, they found voids. Those voids could be places where so-called cryopumping this is just the action of the very cold surface in fact, condensed nitrogen or air or water vapor. So when a piece this size came off, it possibly could have carried ice with it. We simply don't know that; but in the testing, what's going to be done is probably some smaller-scale tests with materials other than just foam, to see what the impact might be.
ADM. GEHMAN: Scott, if I could follow up on that and if I don't state this correctly, you correct me because I don't want to say something wrong. One of the reasons why in the foam impact testing we vary the weight, we vary the density is to cover all the possibilities there might have been something in there, without even worrying what it is. Is that right?
MR. HUBBARD: The initial baseline on the
testing is to try to mimic as closely as possible what was observed, and that's looking like 1 to 2 pounds.
But by varying the velocity and varying the mass, we
can, in fact, mimic or bound, if you will, the
possibility that there were other things in here. The
question on the testing and how far we go is limited by
the number of pieces of material we have to impact, to
A REPORTER: New York Times. Why are you
testing this against RCC that has not flown, when
you've already shown us thermographs of RCC that has
flown that presumably doesn't look like virgin RCC that
has not flown? Will your tests be valid?
MR. HUBBARD: Well, your supposition is
incorrect, Matt. The tests will be in a staged
fashion, and one of the things that the board will
insist on is that we get tests impact articles that are
as close as possible to what was on Columbia. It's
necessary, for purposes of calibration, to start off
with some material that is 20-plus years old from
Enterprise, RCC Panels 16 and 17. They haven't flown,
but they've got the age on them. They will be
instrumented with all manner of sensors so that we can
understand what the impact may have done. Then once
that's known, we'll move on to Panel 6 from Orbiter 3
that does have, in fact, more than 20 flights on it. So the intent there is to be able to duplicate as
closely as possible the type of material that was on
A REPORTER: A quick clarification. Orbiter 3 103, Columbia?
MR. HUBBARD: No, 103 is Discovery.
That's where the used panel is coming from.
A REPORTER: I guess for General Hess.
We're all aware of the images from Hawaii and the
Kirtland Air Force Base which was by the employees on
their own time using the small telescope. Are there
any other images taken either from the ground or from
orbits from U.S. Government assets, of Columbia, that
were obtained incidentally that are available for the
board; and, if so, can we get access to those?
GEN. HESS: Actually there are no other
images that we have. I mean, the images that we have,
you have seen. There is quite a bit of work going on,
as Dr. Hubbard has related, in trying to enhance the
current images that we do have. In fact, Kodak has
done some things to take individual frames and enhance
them. For example, enhancing digitally. It takes one
of those frames and turns it into a 50-meg file. And
they're meeting continuously to try to get the most out
of the pictures that we do have so that we can get more conclusory information from them.
A REPORTER: Washington Post. On your continuing concept of a chain of events and working back from the RCC, have you found any contributing factors in the way the RCC is applied the bolts, the hardware, weak spots that may have been aggravated, may have been lurking beneath the surface, because that RCC panel looks pretty sturdy on its own?
ADM. TURCOTTE: Yes, we have. Throughout the flight history of OV 102, it went through a lot. All but two of these panels were original. We've only replaced, on the left side, two panels a number of T seals which I don't recall, but only two panels.
Now, in that, there's been maintenance,
micrometeor impacts. They've gone back for some
refurbishment. They've gone back through a couple of
different layers of seals and sealing processes back at
the factory, and at the OMMs they are inspected very
carefully. At each of those, there were some areas of
stress that were filled. There were some areas that
were discovered; and as we have looked at the rest of
the fleet, we are finding that in the rest of the fleet
there are some areas of concern. There are some areas
that have been repaired that we don't know enough about
yet to make a judgment. That is part of the ongoing process of looking at ways to better understand what
was really on OV 102 by looking at the rest of the
ADM. GEHMAN: By the way, there are other
issues also. I mean, if Mr. Tetrault were here, he
would answer the same question with a "yes" except
instead of talking about RCC panels, he would talk
about Inconel bolts and corrosion and exposure to salt
air, as we were told by one of the astronauts the other
day that, his calculation, Columbia had spent
2 1/2 years out on the launch pad. So there is
corrosion. So there's a whole series of
strength-and-materials issues here, of which the RCC
panels is clearly one.
A REPORTER: NBC. Mr. Hubbard, could you
show us on the RCC panel exactly where the footprint
hit? Was that on the top leading side or back?
Also, Admiral Turcotte, would you share
with us the preliminary data you received back from
Wright Pat, what it points out at this time? We'll
promise to be big children.
ADM. TURCOTTE: You want me to hold the
RCC panel for you?
ADM. GEHMAN: It's sufficient to say it's
MR. HUBBARD: It's the underside. I was
going to bring up the footprint diagram, but it's on
the underside but it's an area that's so big, you know.
It's sitting on the underside. That's correct.
ADM. GEHMAN: And the radar
ADM. TURCOTTE: The Wright Pat? I will
say that we have ruled out more than we have focused
on, on a number of parts. And I can't remember the
number. Somewhere between a number bigger than 15 and
less than 20 went there, and we've ruled out a lot of
the lesser things. Like blankets aren't very radar
reactive. So we've got it down to a smaller group, but
we don't have a clear enough definition on what that
is. There's more tests to follow, different bands,
different wave lengths we're going to look at to see if
we can refine that even better. So the answer is we're
narrowing down and we're excluding a few.
A REPORTER: Are the carrier panels still
ADM. TURCOTTE: Yes.
A REPORTER: Space.com. I guess for
Mr. Hubbard. Going back to the tests again. You
mentioned the one piece falling off the bipod there.
Are you going to also model that it broke into three,
maybe three smaller pieces, or are you just going to throw that one big piece at it? When you shoot the one
big piece at it, will the RCC panel be modeling this
corrosion and both mechanical issues as well, or just
the raw RCC panels?
MR. HUBBARD: Good series of questions
here. If I forget it, remind me of it. First of all,
the question about big pieces versus smaller pieces.
The piece that I showed you here is one that was
actually observed to fall off. At least from the
dimensions, the mass, the weight and volume, it
resembles what we believe fell off of here.
In 1999, there were a whole series of
tests done with much smaller pieces,
3-inch-by-3-inch-by-1-inch pieces, at the same
facility, Southwest Research, but in a different gun.
One of the plans on the table is to duplicate some of
these tests and carry them further, to shoot small
pieces into other tiles or into some of these materials
and to look at how those pieces might change as a
function of temperature, you know, what happens if a
foam is cold versus being room temperature and so
forth. So there will be, I think, a growing data base
of not only large piece but also smaller pieces, as
Now, at this point, I don't think the visual analysis is conclusive on whether or not there
were three pieces that hit or only one. The frames
simply don't show enough of that; and because of the
impact energy, we're focusing naturally on the largest
piece. But it's clear that we ought to understand what
happens with smaller pieces and we're going to use that
to fill out the test program.
Now, the second question that you had had
to do with how do you simulate a real-life launch
condition. And this is a difficult thing to do because
this orbiter is rising at a velocity that puts a lot of
pressure on the system, so-called dynamic pressure,
maybe 700 pounds per square foot. Simulating this on
the ground in something like that gun I showed you.
How we're approaching that is the
following. First of all, there will be an actual unit
like this that is hit by a piece of foam. It won't
just be a sheet of carbon-carbon. It's the whole
structure, and the structure itself is going to be
instrumented by things called strain gauges that
measure how much tension or compression, by
accelerometers that measure how much vibration goes on,
and by some other devices. Those will, in turn, be
used to calculate from analytic models what would happen under the load of the launch and also to help us
extrapolate to what happens when you take a piece of
Inconel bolt, to use Roger Tetrault's favorite item, to
fracture, how much stress does it take to fracture a
bolt. So we're hoping that between the test approach
and the analysis by all of this instrumentation, we
will be able to give ourselves a good idea of what
happened under launch loads.
Now, clearly if we see some things here
that are very suggestive, it might be necessary to go
back in with more tests, you know, perhaps find out
whatever Groups 1 and 2 have learned about corrosion
and maintenance, and factor that back into the
equation; but we're very aware of the need to try to
test the entire structure system, not just a piece of
tile or a piece of carbon.
A REPORTER: WKMG out of Orlando. This
question is for General Hess and Admiral Turcotte and
it deals more with the war that is going on right now.
How difficult is it for you guys to stay mentally,
physically, emotionally involved in the game, as far as
Shuttle Columbia is involved, when you see what's going
on overseas in Iraq right now? And for Admiral Gehman
also, are we still concentrating, is NASA and the White
House and Congress still making this a priority when it comes to the accident, as opposed to the war that's
going on right now?
GEN. HESS: Well, I can obviously speak
for myself in that, first of all, personally and
professionally, I'm very committed to the investigation
that's ongoing. So I'm not necessarily distracted from
my duties here, but I'm keeping an eye on the war very
carefully and there's obviously part of me that would
like to be with my comrades. But this is a very
important work for the nation to get done, as well.
ADM. TURCOTTE: I concur with that. It's
like we've lost some wingmen in combat; and that's the
way we're looking at this, is going back in and trying
to figure out the reason why. And we are just as
focused. But like General Hess, I'm watching very
closely the events overseas.
ADM. GEHMAN: For my part, clearly the
events that are going on in Iraq have got everybody's
concerns; and everybody's worried about it here on this
board and in Washington. But there are still enormous
things at stake as a result of this investigation. And
there's a lot of attention. We have contact certainly
weekly with the oversight committees, if not several
times a week, and there are a lot of people paying
attention to what we're doing here. So I don't feel any lack of oversight.
A REPORTER: ABC News. A couple of
questions, I think, for Mr. Hubbard. First of all, in
terms of the OEX recorder, is it possible that there
was a strain gauge that might measure the velocity of
the impact that hit the left wing that would be
recorded on that box, the force or momentum of it?
Second of all, in terms of the criticality of foam, do
you have a sense of whether foam was a Criticality 1,
for example, in looking at how it was treated?
MR. HUBBARD: Okay. First question. Could the OEX box have data in it from the ascent phase that measured the impact of this piece of foam? There are sensors on there that are strain gauge sensors, the compression transducers, pressure gauges. Whether or not you could pick out the impact of a piece of foam, even traveling at 500 miles an hour, from the enormous pressures and stresses that are going on during ascent? This period is near what they call Max Q. That is to say it is near the period of maximum dynamic pressure on the vehicle, which is some 700 pounds per square foot. What we have with a 1-or-2-pound piece of foam here is something that would be equivalent to driving in your car at 60 miles an hour and being hit by a 70-pound sack of cement. You're clearly going to notice that in your 2,000-pound auto. Whether in a 220,000-pound orbiter in fact, the whole system here is millions of pounds I would say it's very difficult. Certainly you would be looking down in the noise of this data and seeing if you can pick out any blip or blibbet. And they'll look at that but at this point I would say the signal-to-noise ratio is going to be pretty small.
The second question: Is foam a
Critical 1 material? I guess I would turn to one of my
colleagues here and say: Does that show up in any of
your reviews as being a Crit 1?
GEN. HESS: It has not. I'm not going to
say that it's 100 percent certainty it's not there, but
in our initial looks in the FEMA process to look and
see if foam has been identified as an individual
component, the initial answer we're getting is, no, it
A REPORTER: Palm Beach Post. Forgive me
if this question has been asked in previous weeks. In
your review, have you looked at the discussion on the
foam from the FRR for 113, I believe, and was the
analysis that they did similar to or identical to the
one that was done in flight on 107 or different or
less? If you could get into those details.
GEN. HESS: I think that the STS mission
we want to start with is 112, and we're tracking the
disposition of the foam events from 112 through 113 to
107. And we know that in the FRR process for 107, foam
was not addressed as an issue. We are digging up all
the paperwork on the mission between 112, where we had
a significant piece of foam loss, to 113, to see how it
was dispositioned in that particular event and taken
care of. That analysis is not complete; but before
we're done, we're going to have tracked that all
A REPORTER: Discovery Channel. For
Mr. Hubbard. Could you compare and contrast the data
that you expect to get from the Southwest Research
Institute tests with the engineering analysis that was
done during the 107 flight which determined the foam
impact was not a safety-of-flight issue, and also when
the Southwest tests are scheduled to begin?
MR. HUBBARD: Okay. The analysis that
was done during the STS 107 mission was just that: It
was analysis. What they did was to say we believe the
size of the material that fell off was so and so big.
6 inches by 14 by 24, I believe, was what they were
thinking at the time. And they went to a model called
Crater. Crater is what's called in the trade a semi-empirical model. Basically it's a spreadsheet
into which a lot of data points have been entered from
previous tests; and they said, okay, this is about
where it falls, using this analytical model, this
computer tool, and therefore through three iterations
of analysis or presentations, they concluded that there
would still be enough material in the tiles. This
model focuses on tile damage; it does not have RCC
damage in its data base. There is another much less
sophisticated model that is sometimes used, but this
was a focus on the tiles.
That is different, quite different from
what we're going to do at Southwest. Southwest built
up a data base with small pieces four years ago; and
we're going to go and actually fire a full-size chunk,
as best that can be determined of the right mass and
right dimensions, against existing not only tiles but
the so-called closeout panels, as well as this RCC
structure. So we're going to collect actual test data,
not just run computer models.
A REPORTER: When is the test going to
MR. HUBBARD: The schedule. The first
test will be with the tiles, because that's the most
straightforward way to begin, will be the week of April 6th. I can't tell you exactly which day but
during that week.
A REPORTER: Associated Press for Admiral
Turcotte. I'd like to find out a little bit more about
the flaws that you found in the bipod ramp foam from
the one tank. Do you have any idea what the process
called that, whether it was defective foam, improper
handling or application? How many voids did you see,
and how old was this tank? And just some more details
about the whole thing.
ADM. TURCOTTE: Well, first off, the
amount of voids, if I recall clearly, were 3. Three
small voids that were found when we carefully dissected
As far as the age of the tank
(To Mr. Hubbard) Do you know when 120
was built, how old?
MR. HUBBARD: That's a cousin of 94, but
it's a couple of years old.
ADM. TURCOTTE: Just guessing, it's a
couple of years old. It's not as old as the ET that
was on Columbia, but it's a couple of years old. But
the same process was used. We're looking behind those,
however. There are some process changes that have
happened over the years in the application of the foam; and that's part of what our investigation is looking at
is exactly who did it and what processes were changed
or what was done differently, what propellants perhaps
were used back then and what are being used now. Those
are all part of the investigation. And I might add
further that we're going to go to a sister tank and
take a look at that once we dissect one more bipod
element. And then we're going to come up with a better
test plan and dissect this one a little differently
just to make sure that we did the first two right.
A REPORTER: Aviation Week. For Admiral
Turcotte and General Hess. Admiral Turcotte, on the
RCC documentation for Columbia, did RCC Panels 6, 7, 8,
the general area of interest, have any significant
write-ups or maintenance that you've tied into?
For General Hess. In your management
interviews, have you found any threads or trends, not
necessarily conclusions but threads or trends that are
ADM. TURCOTTE: I'll cover the RCC first.
First off, again, all but two panels were on the
orbiter since it first started flying. So over the
years, you're going to see some wear and tear from both
micrometeor damage or micrometeorite damage and just
wear and tear. So, yes, we've carefully looked at each of the panels. We've looked at the records. We have
carefully reviewed the records page by page from its
last flight, its flow, and have done a cursory review
of the records for its last major maintenance period in
OMM and found nothing of significance that would cause
us anything, any reason to think that we have a
However, I just want to let you know
there is maintenance done on most all of these, and
there has been done for quite some time. Now, we're
looking very carefully at the evaluation methods used
to continue this and keep these in service. That is
primarily the focus of what we're at and so we can
understand what was really underneath those panels.
GEN. HESS: In answer to your second
question, in terms of the management interviews, I
would say we have not found anything provocative; but I
think that's fairly normal. In any hierarchical
organization, you're going to find different
perceptions and levels of information as you work
yourself up and down the levels of that hierarchy. So
some of the disposition that we've seen between E-mails
and our interviews with management about those same
E-mails involve just a matter of the perspective that's
viewed and based on the decisions that were made, as opposed to anything that's out of order.
A REPORTER: CBS. Some OEX questions for
Scott Hubbard. I'm assuming that the 721 possible
things you're measured, is that from mapping STS 109
OEX output so that you know which sensors were active
and which ones might have failed over the years, No. 1?
No. 2, you mentioned that some of the left wing sensory wiring is in the same bundle or I'm assuming you were trying to tell us it's in the same bundle on the outboard side of the wheel well and on the forward edge so that you could lose some of that data but you would still have other data on the recorder that might prove useful.
The last part of my normal 15-minute question is the void in the RCC panels, that void that runs along the wing. I'm assuming there are sensors in the leading edge of the wing or I guess there are and we could, in theory, get some sense of how hot gas is moving through there from the very beginning of this. Is that not a possibility that could give you some indication of where this started?
MR. HUBBARD: Okay. You'll have to help
me here. I may have missed something here. Okay. The
721 measurements is a total and I have breakdowns, but
they're not ready to be distributed yet. I am sure that we, within the next day or two, will be able to
give you a much more detailed release, through the
regular channels, of what they are and where they're
distributed. So the sense of your first question was
where do all these go?
A REPORTER: No, the sense of my first
question is the OEX system, some sensors that have
failed over the years have not been replaced because
it's not an active system anymore. It was my
understanding that the guys were going back to look at
STS 109 to map out which sensors were actually
operational going into this mission, and I was trying
to find out if that 721 was in reference to that.
MR. HUBBARD: The 721 is the best information I have as of an hour ago is that this is by actual count of the beginning of the mission. In other words, this box Columbia, of course, is different. The three newer orbiters have boxes that are similar but not nearly as extensive. They may have 2 or 3 hundred sensors. This was part of the development of the first vehicle, but the 721 is the current sensor count and this is routinely read out after every flight. So when it goes up, they have a tabulation of which sensors are intended to be record; and, of course, that's checked against the post-flight data. So that was the first question.
And the second question was what, Bill?
A REPORTER: I'm sorry. With the cable
runs from the left wing or at least some of the left
wing sensors around the wheel well and you could, in
theory, lose some of those but you would still be
getting data from the rest of the vehicle that would be
of use to you.
MR. HUBBARD: Oh, yes. This box and the distribution of these sensors is all over the vehicle. I was just cautioning that if people expect that, you know, whatever bad thing it was that happened to the other wire bundles in the left wing would or wouldn't happen here is that, if it did, we might lose the data at roughly the same point. But there is data distributed throughout the vehicle, up on the fuselage, on the right wing and so forth. Some of that aerodynamic data could be extremely valuable in determining what the status of the vehicle was. And then finally you asked if the temperature sensors and are there, according to the maps I've got, temperature sensors near the leading edge. This is the hottest area, and that's why the RCC is there to protect it. There are some that are near that; and if those recorded the data and stayed on line, we could hopefully begin a much better map of the temperature flow and maybe this plume of superheated gas.
A REPORTER: Florida Today. I am not
sure for whom. A couple of weeks ago, y'all mentioned
that you were closing out fault trees. I'm wondering
if you've been able to exonerate any systems or
elements such as the SRBs or the SSME shack; and I'm
also wondering if you could give us an update on when
we might see interim advisories, I think, as the
admiral has called them.
ADM. GEHMAN: We don't do fault trees.
That's a NASA methodology. NASA is currently briefing
fault tree closeouts to their chain of command, which
will eventually get to us for approval. We have agreed
with NASA on the process. They have a couple ready to
be closed out, and they have to agree themselves
they're finished. Then whichever group has cognizance
over that area will listen to the brief, and then a
shortened version of that brief will come to the board
for closeout approval. The process of NASA briefing
themselves is going on right now for the first couple.
I don't want to get ahead of them and say this fault
tree's almost ready and this fault tree will be next
because it might get rejected to go back and look at something else.
What was the second part of your question? Oh, interim reports. We have already issued interim advisories that are not interim reports. We are going to issue interim advisories whenever we are satisfied, ourselves, that a certain area should be that NASA should be advised that we've come to a tentative conclusion on something and it is most likely going to be not in our report. If we are satisfied that we studied this enough, we might as well tell NASA about it as soon as possible. We have a couple that are percolating their way up. We looked at them as a board collectively last week. The first two needed a little more polishing and a little more research. So the answer is, yes, we are going to issue interim advisories as the board satisfies itself that we know enough about the subject and it will be useful for NASA to know about it.
A REPORTER: NASA TV. This one will be
for Scott Hubbard. Your analysis showing that the
debris hits the leading edge of the wing suggests that
NASA mission management simply called it wrong during
the mission in terms of where the debris hit. Can you
comment on that and can you comment on that with
respect to the gap filler tile or carrier panel tiles or whatever you're calling those tiles? And is that an
issue, the fact that if they missed the call, you know,
should they have done their work better in terms of
figuring out where it hit?
MR. HUBBARD: Well, I don't want to get
ahead of the other teams that are looking into
management decisions and what the various processes
were or checks and balances for decision-making during
the pressure of a mission; but what I can say is this,
that to get to this point, of being able to say within
an error bar of a foot or two where this hit, required
weeks of data analysis. We're at the two-month point
here. This data had to be washed and cleaned and in
some cases digitized, studied, evaluated. New models
had to be created in two dimensions and then made into
three dimensions. Coordinates had to be translated.
So there was a huge amount of work to get to this point
to be able to say that this is really looking like
where the pork chop impact region was here. So whether
or not that level of analysis could have been done
during the middle of a two-week mission, I am not
prepared to speculate on. It has taken quite a bit of
effort to get to this point, though.
A REPORTER: And just the other part of
that, too, where the carrier panel, the tiles. I mean, do they behave differently than the other tiles on the
MR. HUBBARD: Well, right here you can
see I've highlighted two closeout panels, carrier
panels. What these are are the black tiles that cover
a lot of acreage on the bottom of the orbiter, but they
have attach points into a metal structure. So maybe if
you can hold that up again there, we can highlight what
we're talking about. So you see those tiles on the
front there? Those are the kinds of tiles that you
find on the bottom of the orbiter, but they have some
differences. One is they're scalloped out on the edge.
In fact, these things are attached on the
top by four bolts and on the bottom by two bolts and
they are, in fact, scalloped out of this side. So this
side here has less material on it than the acreage
that's here. And, of course, there's all the structure
that goes on underneath. So, yes, the thermal
protection part of this is a similar kind of ceramic;
but the structure of it is something different.
So, for example, if this pork chop shaped
or lamb chop shaped piece of region happened to hit
that just right on the edge, you can imagine snapping
that off. Whether or not that's what actually
happened, that's part of what the test is going to do.
A REPORTER: New York Times. For
Mr. Hubbard. Actually I have a question that I already
asked you a couple of weeks ago or more. Aside from
the foam that disintegrates after it hits the underside
of the shuttle, there's also another piece from another
view, from another rear view of the beach tracker, as
they call it, where you see this piece of solid
material that seems to either hit the shuttle and
bounce off or I was wondering if it is actually coming
off the shuttle. And it is not a piece that
disintegrates. It looks like a solid piece that
remains in one piece.
MR. HUBBARD: I'm not sure if that has
been validated. You know, the focus is on the big
piece that obviously did hit about in this region,
because that's the one that would have done the most
damage. Smaller pieces seem to be visible; and one of
the reasons that this very high-resolution, digitized
version of the film is being prepared is to, in fact,
go and evaluate that next level of detail. As General
Hess said, a study of that is in process. What kind of
impact it could have had at this point is speculation;
but as I said, that's one of the reasons that tests are
being run with smaller impacters.
A REPORTER: Have you looked into the possibility that that actually could have been a piece
of the shuttle coming off as a result of the impact
with the foam?
MR. HUBBARD: I don't think that that scenario has received very much attention because, if I can back up here well, it's not I thought red was reverse. Okay. Never mind.
The impact footprint from all the
available visual data shows this column that's 2 to
3 feet across that proceeds from the bipod ramp area up
here and goes down and hits the wing. There is no
other data at this point that suggests anything came
off from elsewhere.
A REPORTER: Houston Chronicle. I have
two for Admiral Turcotte. Are the RCC Panels 6, 7,
and 8 among those that were original to Columbia?
ADM. TURCOTTE: Yes.
A REPORTER: On the radar cross-section
tests, I could not hear your earlier answer on this;
but I just wondered if tile ice, carrier panel, and RCC
are still in the running among candidates that the
returns could indicate was what was coming off the
ADM. TURCOTTE: Most anything that is a
hard object like what you see there is still in the running. What we've really taken off are some of the
blanket materials, some of the frizzy blankets, those
kinds of things that are much smaller and did not have
a big cross-section; but I will say it's preliminary.
We haven't done a full analysis. There is more in
different frequencies, different wave lengths to be
looked at. So those could be brought back on the
A REPORTER: SpaceFlightNow.com. I think
this question's for General Hess and perhaps Scott
Hubbard, as well. Just to revisit the 112
foam-shedding incident. We haven't really received
much information about what damage was done to the
solid rocket booster. There was some documentation
from NASA released in the last week that said there was
a 4-inch-diameter-by-3-inch-deep impact site on the
booster. I'm wondering if you know any more about that
and whether you think it's strange that in the
following Flight Readiness Review there was really no
reference to an impact on the booster, it just dealt
with the fact that foam shedded.
GEN. HESS: I think the information that
we have is consistent with what you just suggested,
that there was a strike on the solid rocket booster. I
have not seen the actual picture of that particular strike other than just the post-mission reports of it.
I've forgotten the second half of your
A REPORTER: It was whether you thought
it was strange that, in the discussions that seemed to
follow at the next mission's Flight Readiness Review,
it seemed like there was little reference to the fact
that a booster had been struck, it was just that foam
had separated from the tank.
GEN. HESS: I don't necessarily want to
agree with your characterization of thinking it strange
right now, because that would mean I've decided
already. We are going to take a look at how that foam
event was dispositioned from 112 to 113 to 107. It's a
little bit difficult to track it through the safety
process. So by the time I get back to Houston,
hopefully, we're going to have all that data lined up
so I can actually track it and determine for myself was
it declared to be an in-flight anomaly and, if so, how
was it handled. If it was an in-flight anomaly and
handled as some lesser safety event, how was that
disposition and was it handled at a lower level? All
their actions may have been appropriate, but I need to
read it all myself in a consistent fashion before I can
make a judgment on it.
ADM. GEHMAN: I want to comment on the
112 foam strike. I mean, you saw the skirt, didn't
ADM. TURCOTTE: I saw a little bit what
he's talking about. Just from the technical aspect, it
was soft on soft. It was a part of a cover that had
some other rubber material on it. So it was not a
metal or it was not a hard object that it hit. So that
was essentially the results of that analysis. Now,
where that fits into the rest, I couldn't tell you.
A REPORTER: Orlando Sentinel. For Scott
Hubbard, I believe. I understand that, along with all
the other debris you're analyzing in the hangar, that
you're also looking, of course, at remains of the crew
compartment, which I guess are kept segregated from the
other pieces of debris. Could you talk a bit about how
much of the crew compartment you've recovered so far,
what it shows as far as damage is concerned, and where
the pieces were recovered along the debris track and
what sort of big-picture conclusions you can draw as
far as the forces it was subjected to and when it came
ADM. GEHMAN: I'm the crew compartment
guy. You are correct: Anything having to do with the
crew is being reconstructed in the hangar, but separately. Anything that we learn from the crew
equipment, crew compartment is examined; and if it's
relevant to the investigation, if it tells us anything
about the cause in the investigation or characterizes
how the orbiter came apart, we then carry it over the
top of the curtain and put it out on the floor. If it
doesn't support our investigation as to what caused
this accident, then we don't take it across the
curtain. As far as questions like how long did the
crew compartment stay together and things like that,
we're not commenting on.
A REPORTER: L.A. Times. Could you tell
me whether, when the RCC panels were originally
designed and manufactured, whether there was a
specification that it had to withstand a certain burst,
a so-called burst strength or some type of intrusion
specification and then, secondly, can you tell me if
you've made any determination of whether ageing, these
microfractures, these worm holes and voids, how much
that would have reduced that strength?
ADM. TURCOTTE: First question, on design
specs. This was designed primarily to withstand
orbital debris types of impacts, and there was a number
of tests done at very high velocity low mass that
showed different failure modes. And the majority of those failure modes were survivable. Part of our
investigation, to my knowledge right now, there was not
any testing done on ascent impacts of high mass and
relatively medium velocity. That's part of what we're
looking at right now, and that's why we're doing the
testing that we're doing.
Part 2. The ageing. This is a carbon
fiber substance. It's got a porosity value of about
20 percent. It is very strong; but as in any composite
material, it does age. Over those years, they have
done extensive maintenance on it; and, yes, we have
found some areas that have been repaired and brought
back to life. We have seen a lot of cracks. We have
seen some oxidation. Based on the inspection that
we've done and the process that we've done, we've taken
some out of service and replaced them. So, yes, they
have aged. To what extent is part of what we're
looking at very closely now to come up with a baseline
assessment of the density and the actual makeup or the
nature of really what we're looking at across the
A REPORTER: Was there an actual
ADM. TURCOTTE: There are design specs,
yes. And I don't have them in front of me but I can tell you they are X amount of millimeters thick and if
they fail that, then after that you replace them.
Those kinds of specifications, yes.
MS. BROWN: We're going to take three
questions from the phone bridge now.
A REPORTER: For Mr. Hubbard. Forgive me if you said this earlier. First of all, with respect to the OEX
MS. BROWN: Can you say where you're
A REPORTER: Washington Times. With
respect to the OEX, is it too early to know whether or
not there is a magnetic signal on the tape?
MR. HUBBARD: Yes.
A REPORTER: Secondly, what's potentially
the most important information you can get from that?
Then with respect to the foam testing, can you describe
the equipment used to fire the foam itself; and do the
tests take into account that the foam might have ice or
something like that?
MR. HUBBARD: Okay. The first question
was is it too early to know if we have a magnetic
digital signal on the tape. Yes, it is too early.
That's what we hope to find out within the next day or
two when the tape is duplicated here at the Kennedy Space Center.
The second question is the most important
information. We have focused a lot of our attention on
the left wing and particularly the left wing leading
edge. If the sensors that are there were active and
working and got recorded, that information would be
extremely valuable. As I said in answer to an earlier
question, though, if for some reason those sensors
dropped out, the orientation of the vehicle from some
of the other sensors could also help us determine the
attitude of the vehicle; and that might give us a
better sense of what was going on.
The third question was about what's used
to fire the foam. It is a nitrogen-pressurized gas
gun, and I think the sense of your question was how are
we going to make it as much like the real event as
possible. We're taking every precaution to see that
the size and the mass and the velocity and so forth are
like what was observed, and we're using all the sensor
data that we'll get from instrumenting these pieces and
therefore using analysis to determine what would have
happened to the whole structure. So we can't duplicate
everything, but our intent is to do a lot of analysis
from sensor data and extend our knowledge out to where
we don't have test data.
A REPORTER: Daily Press. According to
NASA Langley Public Affairs, the investigation board
interviewed Langley engineer Bob Dougherty and one of
his supervisors, Mike Stewart, yesterday. I was
wondering, now that you've interviewed them, what, if
anything, you have to say about the significance of
their E-mails, the ones that were written before this
disaster, and were they handled appropriately and, if
you don't know, if you can't say now, when do you think
you'll reach the point where you'll be able to give a
conclusion of whether these E-mails were significant or
GEN. HESS: This is Ken Hess. I haven't
heard the outcomes of those interviews yet. Those did
take place at Langley yesterday and there is a task
force that runs along this seam between Group 1 and 2
that are conducting a lot of the background interviews
that have to do with those E-mails. And I have to
plead a little ignorance on the outcome of those
A REPORTER: Richmond Times Dispatch. A
follow-up on that, General. You had talked earlier
about keeping the E-mail exchange in proper context.
What is the task force and your team learning about
that proper context and the safety management issues, and could you describe in more detail how you're going
back to the Rogers Commission safety recommendations
and how they are implemented today at NASA?
GEN. HESS: Let me see if I can answer
those. First of all, it tied together a couple of
different aspects of what we are learning as you take a
complete look at NASA and their organization or
structure. One is that, being a very hierarchical
organization, there are certainly levels of information
and decision processes that are made at varying levels.
That becomes very, very evident to us in terms of how
we view the overall process of making a decision like
the COFR, because lots of information gets worked at
low levels and then it's basically informed through
their committee process, if you will, because there's
no way that the top executives of NASA could handle the
volume of information that's required to get a shuttle
commitment to launch. So there a lot of checks and
balances to a process that reports out key issues and
the most important issues to the leadership.
So as you begin to look at the levels of
information that are available at any particular level,
as well as the relationships between the various
groups, you begin to have an appreciation for how the
E-mails could have been perceived or how dialog between one particular group may have been perceived. And if
we stand back from it as not being part of it, well, we
can draw any number of conclusions. So we have to be
very careful that we understand all of those
relationships when we come to our final commitments to
how we think that the issue was handled, be it for DOD
imagery or for a decision on how the crater analysis
was applied and how it was reported up the chain to the
leaderships in the FRR process.
Secondly, when we take a look at the
safety organization, the part that we want to take a
look at and have an appreciation for is the level of
oversight versus insight as well as what that means to
the management levels. I mean, there is safety in the
workplace where you're worried about loss of workdays
and stuff; and all the statistics are excellent here.
We have no indication that the NASA USA contractor
family is not conducting a very aggressive safety
program; but when you work the levels up and you try to
ask yourself is there a fair balance between management
and then independent safety oversight as I think was
envisioned in the Rogers Commission, then we have to
judge that a little bit differently. And we're doing
that through getting as much information as we can and
interviewing everybody that's involved in that process so that we can form a board opinion on whether or not
we think that process is effective.
MS. BROWN: Thank you very much. That
will conclude the press briefing for today.
(Conference concluded at 2:16 p.m.)
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