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Columbia Accident Investigation Board Press Briefing
Tuesday, April 29, 2003
1:00 p.m.
Center for Advanced Space Studies
Lunar and Planetary Institute
3600 Bay Area Boulevard
Clear Lake, Texas
ADM. GEHMAN: Good afternoon. I've got a couple of short announcements to make.
The debris search is winding down as per the schedule that we approved. The ground area of primary search is 99 percent finished, and the organized large-level-of-effort debris-searching will cease on the 30th of April, as we indicated.
The board is quite pleased with how much of the orbiter has been recovered. We're sneaking up on 40 percent. We won't quite get to 40 percent, but it will be 38 or 39 percent of the dry weight of the orbiter will have been recovered, including a number of significant pieces, which has helped the investigation considerably. There will still be a debris recovery office located at JSC which will remain open for weeks and months, for anyone who happens to find debris; and also there will be an occasional debris search located at various high-probability areas, particularly out west as time goes on.
During this week we did find another tile in the vicinity of Granbury, Texas, which at one time, remember, was the westernmost tile at one time. So that piece of tile has not yet been identified as to where it came from, but that makes now three pieces of debris that have been found significantly west of the Dallas/Fort Worth area. So as we examine that piece of tile and find out where it came from, I'm sure we'll learn more.
The U.S. Forest Service and the Texas Forest Service, who have been providing most of the manpower, of course, are repositioning themselves for what they do most of the time, which is fight forest fires. They're from all over the country, including Alaska, and they are now going to their home bases and getting a little time off and preparing themselves for their season. We are very grateful to them and to everybody else that participated in this very important piece of the investigation. The importance of debris will be brought home later in this briefing when Mr. Tetrault gets to talk to us about debris; and you'll see why we keep bringing debris up over and over again because it's one of the things that really helps us with this.
This has been a big week for the board in that we did some heavy lifting this week in two areas, none of which are newsworthy; but in both areas, at least to me as the chairman, I think it's significant.
The first one is in the development of what I call a working hypothesis or a working scenario. We released a little press release on Thursday afternoon after we had a very long and detailed meeting with everybody that's involved with this, both our own staff and the NAIT, the NASA Accident Investigation Team, everybody who knows anything about this. They briefed us. We had several briefers to the board, and we made some progress in agreeing on something which I am calling our working hypothesis.
We are not finished with that. We have appointed a subcommittee to continue to refine the details of this working hypothesis, but we made a lot of progress and did quite a bit of hard intellectual work in order to narrow down choices and eliminate some choices and satisfy ourselves that we know enough to agree on a working hypothesis without inadvertently eliminating something which might be important later. That work will continue and in the near future, I hope, seven to ten days, we will announce what is our working hypothesis. I can't tell you what it is right now because we're still working on it, but I can tell you in general terms it is a hypothesis which narrows down the options of how heat got into the left wing and the process by which the left wing of the orbiter was damaged. We have mountains of data and mountains of debris, and what we have to do is see if that debris agrees or conflicts and come up with a hypothesis that agrees with most of the things but for which there are no conflicts.
The test that we have is that not all the data have to agree with our hypothesis but there can be no conflicts. So we can't have any evidence which says that our hypothesis is no good. So that the board worked on for hours and hours, continues to work on very, very hard, and we will press that with some degree of urgency.
The second area that we did a considerable amount of work on, hard work, is in the area of risk assessment and understanding safety engineering and safety systems engineering. The board is satisfied that we have adequately founded our work in thermodynamics and aerodynamics and things like that with subject matter experts which are world recognized, world-class experts, and the board is satisfied that we are not likely to be challenged on any conclusion that we make as to an aerodynamic event or a thermodynamic cause or effect or something like that.
If the board is going to make some recommendations or some findings related to management, safety, risk assessment, or anything along those lines, the board feels that it needs to be equally well founded in that area of expertise. So what we've done this week, both in our public hearing which we held on Wednesday at which you heard about risk and various types of risk and different ways to look at risk and how the original designers of the shuttle looked at risk and how theorists like Diane Vaughan and other people look at risk -- we also had in conversations and briefings and meetings with the board, about a day and a half of more experts from industry, from the academic world, from the National Safety Council, in which we were apprized of other ways to study, measure, analyze, and make comments on risky activities in high-reliability organizations.
You might call this an education process. We were not evaluating NASA. We were putting ourselves into a position in which, when we do write something about risk management, that we can do so with some authority and we can do so with some knowledge -- once again, to put ourselves in a position like we are in the area of aerodynamics or debris reconstruction or something else where we have sufficient expertise that we are not likely to be challenged by somebody who has a different opinion. This is very hard work. It takes a lot of time. It takes a lot of patience. Sometimes I, for one, get a headache doing it; but it's very important.
We had four visits by members of Congress at our headquarters this week, and they are always welcome. The four members were all from the House, and they were all from the oversight committees, either the House Science Committee or the Subcommittee on Space and Aeronautics, and it's extraordinarily helpful to me to have this dialogue with members of Congress because we want to make sure that our report hits the bulls-eye when we write it. To so some degree, Congress determines where the bulls-eye is. So if they move the bulls-eye on me a little bit up or a little bit to the left, I need to know that so that I can structure the report that way.
In addition to that, I am leaving later this week to go make some more calls on Capitol Hill, again with the chairman and the ranking minority members of the oversight committees on both the House and Senate side, just to make sure that the work of the board meets the expectations when we get finished. As you probably are aware, the chairman of the Senate Commerce, Science, and Transportation Committee, Senator McCain, has called for a hearing on the 14th, at which I will be appearing.
Lastly, again, board-wide activities, is the board has just initiated -- and we don't have anything more to say about this than the fact that we've initiated it -- a line of inquiry into the ascent phase of the flight. That we intend to be as detailed and as rigorous as is the inquiry into the entry. There are a few things in the ascent phase that are interesting to look. One thing, of course, is the foam strike; but there are other things in there like aerodynamic forces and control surfaces which moved not out of limits but right up to the edge of what has ever been seen before. So we would like to examine those and some other things with the degree of intensity and the degree of detail that we have picked apart the entry scenario. I'll let my colleagues talk a little bit more about that, but I'm just going to say that we're just starting that and we find it to be interesting.
Let's see. I think that that's it. We're up to 78,000 pieces of debris now, for people who are keeping track; and they still come in at the rate of several hundred a day. So I will now call on my colleagues to talk about what their groups are doing.
General Barry, you have the floor.
GEN. BARRY: Good afternoon. I've just got a few things to talk about this morning. First of all, on Group 1, Maintenance, Management, and Materiel. Rear Admiral Steve Turcotte and Brigadier General Duane Deal will be going to KSC this week. They'll be leaving tomorrow, following up on some interviews and some other working investigation down there.
We've got a couple of subgroups that are being worked. We've got Bob Ballister and Commander Mike Francis who are working on the ascent time line, as the Admiral mentioned, and we've got another subgroup, Colonel Nakayama and Colonel Beer, who are going to be as KSC for follow-on interviews and infrastructure investigation.
We also hired a Dr. Roger Staley. He's a former professor at the University of Minnesota and Ohio State University, for corrosion analysis; and he's going to be down at the debris site and doing some work for us on some of key items down there.
A couple of things. Maintenance. On the maintenance effort, the next closeout fault tree that we are going to be examining will be on the solid rocket booster. Estimates right now is that's to be done in the middle of May. There will be one unresolved area that the NAIT, the NASA Accident Investigation Team, will be bring forward; and that will be on the bolt-catcher. So outside of that, they will bring everything forward about the middle of May.
Can I have the first slide. I want to talk about Day 2 debris. I know there's been a lot of debate in the press about. I'll give you the current debate from where we are. Right now, as has been mentioned before, the post-flight analysis really was after, of course, the mishap. We went back and examined the data.
There are two qualifying gates to figure out if this, in fact, was a valid debris that we saw on the second day; and those two gates have to be with the radar cross-section. There are 26 items that have been looked at. I will show you. There will be five more added and then, of course, the area-to-mass ratio. The radar cross-section is done at Wright Patterson Air Force Base. Dr. Brian Kent and Dr. Bob Morris at Colorado Springs for Space Command does the area-to-mass ratio.
So we've got two candidates that are still out there, and I will show you the next five. The RCC T-seal and the wing leading edge insulator.
Next slide, please. You can see over here; these still are not excluded. So we're still holding them as potential candidates. There's a lot written on the T-seal. Right now we've got Roger Tetrault who will be talking a little bit more about that in regards to what T-seals we think and the areas insofar as where the heat might or might not have come in.
The other five listings there are additional candidates. Those are all from the debris field that we have down at Kennedy Space Center, and those will be examined not only for RCS but also for area-to-mass ratio. So you can see a couple of those. There's another T-seal section. There's some RCC fragments that we want to look at and another carrier panel. This is the upper carrier panel. So we'll continue on this detective story as we continue on the investigation.
Next slide. This is just to show you an example. This happens to be the T-seal that you can see over on the left-hand side and how it fits in within the parameters as listed from the Wright Patterson laboratory. So we're trying to narrow this down as best we can; and as we get better information on what's going on with the debris, we'll be able to maybe zero in on this. It's like a sine curve, you know, and then eventually it gets kind of dampened out and we finally figure out where it is that we want to have on the final part and hopefully we'll conclude or give our best example of what we think that second day debris is.
Okay. Slide down, please.
A couple of other announcements just to make. We've got notification from U.S. Strat Com. They were put in charge of the DOD Columbia Investigation Support Team, and we've been in contact with them since Day 1. We were notified by letter that the DCIST or DOD Columbia Investigation Support Team has completed their collection and analysis of DOD information related to the flight, STS 107, and all analysis has been provided to the Cape. They're unaware of any further data or information relevant to the Columbia accident, but they're on call to continue to expert us as needed. So we've run that to ground, full circle.
The other one I want to announce also is we're getting a briefing today from Ralph Roe, and he's going to outline for the board the RCC NDE plan. That's non-destructive evaluation for the reinforced carbon-carbon. As you know, we've put out a preliminary finding; and that finding called for a more detailed NDE evaluation of the leading edge and the RCC in general.
A final point is on the management and human factors. We have a team made up of multiple groups within the board, subgroup members who were at Huntington Beach this week, and they are going to be concluding the investigation on crater and the transition of the Boeing Huntington Beach shuttle analyst support that moved from California mostly to JSC, but some to KSC.
That concludes my remarks.
ADM. GEHMAN: Thank you very much.
Dr. Ride.
DR. RIDE: Thank you. I'm here representing Group 2. Steve Wallace also and General Hess are both in town this week, and we're all pretty heavily involved in the aspects that I'll discuss.
We've finished the assessment of launch controller training and have found that not to be a contributing factor, not to be an issue. We've uncovered nothing remarkable in that training activity. We're right now deep into two other activities that you have heard something about. One is documenting the analysis and the disposition of the foam events. These are preceding and including STS 107. We're going to start with STS 32, a major bipod foam event; then skip to STS 50, another one; and then do 50 through 107, looking at the major events. For each, what we're interested in, our particular group, is how that event was handled through analysis, through briefings at the various reviews after the event, how it was taken up through the chain, was it declared an in-flight anomaly or not, was it briefed at the FRR or not, was a hazard analysis done. We're still in the middle of gathering information.
As you can imagine, this is a fair amount of information. You've seen briefing charts at some of our public meetings that showed the cataloged number of hits per flight. We're going quite a way beyond that, into the briefing charts after each flight and the minutes of meetings and that sort of thing, to really try to put together the story of how foam strikes were handled through the relatively recent history of the program.
That history of the foam strikes and the response to them kind of sets the stage for the decision-making that took place during STS 107, and that's the other principal area that we're involved in at the moment. We're continuing what is really very time-consuming work in documenting that decision-making process. We've nearly concluded but not concluded a pretty extensive set of interviews in this particular area and we're just at the stage where we're now starting to assess how the organization functioned and we're going to try to, in the next week or two, be stepping back to be able to take a look at the organization and how it responded to this. We think we have a fairly good understanding now of what happened, but what we really want to get at and what we think is the important piece of this is how did the organization function, because that's something that we can hope to make some constructive comments on.
As a part of this, we're bringing in some experts to help us develop the context and how to analyze and assess these processes. As Admiral Gehman said, we've got good grounding in aerodynamics and thermodynamics and we want to make sure that we avail ourselves of expertise in the safety and risk assessment area. So that's what we're starting to reach down to gather right now. You've heard from Diane Vaughan last week, who we had in. We also, as the Admiral mentioned, had a group of safety and risk assessment experts, accident investigation experts in yesterday. Allen McMillan from the National Safety Council, Jim Wick from Intel, Deb Grubbe from Dupont, Sam Mannan from Texas A&M, Nancy Leveson from MIT, and David Woods from Ohio State. So it was a good representation of industry corporate safety culture, safety organizations, and also academia; and we're really trying to understand what they can teach us and how they can help us to develop some methodology and constructs to make sense of what we're seeing and to, as I said, try to say something intelligent and constructive about the organization and the decision-making process.
The things that we saw in this accident, we're learning, are not different from things that are seen in other accidents or other areas of investigation, whether they be in health care incidents or whether they be in chemical industry accidents. So we're really trying to learn from the experience that they've got. We also want to get a perspective on safety and risk from recognized experts in corporate America and academia, how do they deal with safety through their cultures, and all of this is really to help us get a perspective on how does a large institution instill a safety culture, how does an organization approach developing metrics and using metrics that serve as advance indicators that there may be potential issues that should be paid attention to as they go forward.
We also got what we think is a pretty important briefing and reminder about hindsight bias. Hindsight is always 20/20, whether you've been watching a football game or analyzing a space shuttle accident; and it's very, very important for us to take advantage of some of the literature and some of the expertise that's out there on how to avoid hindsight bias and the importance of putting yourself in the place of the people who were involved in these decisions at the time. There's quite a bit of literature about that that we're getting some good insight into.
Again, we had some introduction to different sort of accident investigation models that we hope to use to be able to get at generalizing that we found in this investigation and pull, you know, kind of the gems on the organization. Perhaps it's processes. Maybe it's bias. Maybe it's tendencies. We don't know, but we think there are models out there that can actually help us, instead of trying to reinvent the wheel from a bunch of physicists and technical folks, but take advantage of a lot of rich work that's been done over the last several decades to help us make sense out of it.
I'll just add as an aside that one of the briefers that we had, David Woods, has done extensive work in analyzing decision-making in mission control, as well as in health care and other areas, and he in the past has found mission control to be the positive example in terms of how to handle decisions in real time and crisis decision-making. So he's got a lot of insight into the way that decisions occurring during a space flight are normally handled. So we expect to get quite a bit of help and insight from him.
ADM. GEHMAN: Thank you very much.
MR. TETRAULT: Good afternoon. I'm representing Group 3, which is the technology group, if you will. My teammates this week are busy. Sheila Widnall is at MIT. Scott Hubbard is leaving to go to Southwest Research, where the foam tests will begin on Thursday. Dr. Doug Osheroff is here from Stanford, and he's working on chemical analysis of debris. Dr. Jim Hallock is also here, and he's working on fault tree closeouts and sensors.
What I would like to do today is go ahead and do a quick review of the critical evidence that indicates the location that we are seeing in the breach of the left lower wing. I'm going to very quickly note two items and then come to this slide. All of you have seen the photographic analysis that showed the foam coming off the external tank and striking the RCC panel area, which is measured to be in the 6, 7, and 8 lower-wing area. You've also heard General Barry talk about the Day 2 radar event. The importance of that particular event, as far as I'm concerned, is that the OEX sensors show that very early on in this particular incident we have heating in the left wing; and that, in turn, indicates that the breach was probably there and that it existed at interface. Certainly if that's a fact, then it lends credence to the potential that a piece left the left wing, departing sometime during flight, and is the piece that we're looking for on the Day 2 radar event.
Now, let's look at this debris because that begins to point us into specific area in the left wing where we have some concerns. This debris shows some debris from Panel 9, 8; and this is 8, as well. What we see is there are some very unique events happening at Panels 9 and No. 8. These are the ridges, if you will, that go to the RCC panels and are normally attached to the panel on the sides. What is unique is that they have knife edges on the sides, which are shown here; and that is obviously a sign of high-temperature erosion during re-entry. Again, we don't see anything like this anyplace else in the debris field. We also have a very heavy element of slag that is molten metal which has been thrown forward on to the back side of the reinforced carbon-carbon panel here at Panel No. 8. Then in addition to that, there was a third element that was unique in that the carrier panels which would be located out in this area, we do have the tiles from the RCC No. 9 area carrier panel and those tiles are significantly slumped and molten compared to any of the others that we have seen. So those are the unique features which are pointing us kind of in that area, or at least were up until fairly recently.
In fact, probably the favorite hypothesis which we were using at that particular time was, since this particular T-seal was missing, that it might very well be the T-seal between these Carrier Panels No. 8 and No. 9. And there's reason why we favored the T-seal.
If I could have the next slide. It's because it made a nice gap through which we could see the potential for entry of hot gases creating the kind of incident we had, and it offered a protected area. This is the gap, if you look at it here. What I've shown is a make-believe T-seal covering the upper part of the wing, if you will, leaving a gap without the T-seal if the bottom half of the T-seal had been extracted. If that gap is there without any of the T-seal structure, including this rib face here, then you would have a gap of 1.15 inches. If the rib face remained in, such as it is here, and the gap was the size of this red piece, then it would be .775 inches.
Let me have the next slide, please. Now, one of the reasons that we favored the T-seal was because we saw a lot of T-seal failures in the debris down at Kennedy; and there were three different failure modes that we observed while we were at Kennedy. The first of those failure modes is a cross-sectional fracture, which is shown here in Photograph A, where we just cut across both the rib and the face plate and it separates. The second failure mode was a face plate fracture, which is shown here in B. That would be this plate, which is normally the sliding plate against the RCC, breaks off at the intersection with the rib. Then finally there is a flange fracture where you can slap this face -- and this is not the best photograph of it -- but you can slap this face and the rib actually pops off. So you may have the entire face or some piece of the face, as we have here, without attachment to the rib. So those are three different failure modes that we've seen in the debris; and recognizing that they do, in fact, fail or could, in fact, fail, we tended to have a preference for a T-seal as a potential culprit and where the breach occurred.
Next chart. Of course, as many of are you aware, last week NASA put a piece down on the floor which was labeled as being T-seal No. 8. This is in the gap between Panels 8 and 9. This is the area that we previously had thought we didn't have a T-seal for. They put this down as being certain that it was in the right spot. A subsequent audit of that proved that it was not a certainty, that, in fact, it was probably something less than that and maybe in the 70 to 80 percent range.
What brought them together on this issue is, in particular, this erosion mark on both sides of these pieces; and these two pieces do appear, because of that erosion mark, to be coupled together. When you couple them together, there are very few positions that you can put this piece down at. The preferred position was, as I said, at Position No. 8. However, since that time they have been doing additional work; and as of this morning, we have found similar erosion to this pattern here, in Position No. 10. So we're uncertain at this time whether this piece belongs in Position 8 or Position 10. It's probably a 50/50 at this particular point, so the potential of having no T-seal between Panels 8 and between Panels 9 is still a possibility.
Having said that, I'm now going to move away from that T-seal. If I could have the next slide, I'll begin to show you why we are actually moving more inboard on the wing in terms of where we believe the event actually occurred.
This is a shot of an X-ray taken of RCC Panel No. 8. There's actually three pieces of it. If you're familiar with what's been going on, these three pieces are all top half. So we have no bottom half of RCC Panel No. 8. What you see on the X-ray, you do not see visually when you look at these pieces of the RCC; and what you begin to see is deposits of heavy metals in certain patterns that we don't see when we look at it visually.
Let me show you what the patterns are. If you look in this area, you can see that there's definitely a pattern to how this area is being laid down. What you can't see from the photograph that I'm showing you is that, in fact, when you get down into this area, there are small nodules of metal which are being deposited in a very uniform pattern, going straight vertically up and down; and this would be where the RCC attaches to the T-seal. So it gives you an idea of how that orientation is. This orientation is on the side.
So we are going, if you will, if you stood behind the RCC panel and took a paint brush and sprayed it at the back of the RCC panel, you would get deposits that were very similar to this; and they're very uniform and very straight up and down. That begins to indicate that we're not getting a lot of side flow from, say, a T-seal position or even a panel further back.
Now, let me go to the next chart. This is a closeout photograph of the spar area, looking from inside the wing at the wing spar in the front. What I'm drawing on here are six out of the 15 wire runs of OEX sensors that run from basically left to right toward the fuselage. We haven't plotted all 15 of these yet because they're extremely difficult to plot. You have to virtually do them by eyeballs. The drawings aren't necessarily correct. For instance, the drawings actually show only three bundles; and as you can see from here, there are five bundles.
What I've also plotted is where we are directionally behind the spar. If you look at these four bolt heads that go through here, that's where T-seal No. 8 would be. That's the T-seal between RCC Panel No. 8 and RCC Panel No. 9. So that's the area of the T-seal. RCC Panel No. 9 extends from here to here; No. 8, from here to here where this spar is.
I've drawn the wires in here and shown you where they run, and in some cases I put them front of obstacles so you can follow them, instead of behind the obstacles. For instance, here obviously it wouldn't go across the front of this truss bar, it would go behind it, but I wanted you to be able to see and follow how they go.
The red one is a very famous sensor. That's the temperature sensor that goes out on the front end of the spar in the clevis area between 9 and 10, and that's coming in as one of the furthest out and running right along the center. Now, what's interesting is on the far left. As I've shown you, the order of failure in seconds from entry interface -- and these are the failures of those wires which we presume are being cut.
If you look at this, it tells us a few things. One, they're being cut from the center outward. They go red, then yellow, then blue, and then deep blue. So it's going outwards. It's coming from the center. Two, it includes failure of these two wires, which obviously tells you that the breach is not anywhere outboard of this area. If it was, it wouldn't be cutting these two wires. So it's beginning to localize this; and what you see then is it's localizing it further into 8 and away from T-seal No. 8.
Okay. In addition, what we see is this wire, the green one, which is this one right here, is the last one to go off, by some 25 seconds, which is a substantial period of time. So this breach, if you will, is progressing down the wall and hits this one. As you turn this corner -- I haven't shown this picture, but this wire actually comes back up in a short span of time and connects back to these bundles. So what this differential in time also suggests is that the breach and the cutting of these wires occurs somewhere in this area and not likely to be very far to the right of the picture that I'm showing you because otherwise this wire bundle would have been cut much sooner.
So the bottom line to the presentation I'm giving to you is that we don't know yet whether that is a T-seal No. 8 or whether it belongs in Position No. 10. It's probably 50/50. It is not likely, based on what we're seeing, to be that significant that we are moving slightly to the right and, as the General said, we've had this oscillating pattern of where it is but it's getting closer and closer and I feel that we're probably within 30 inches of where the actual breach occurred now.
That's all I have.
ADM. GEHMAN: Thank you very much.
LT. COL. WOODYARD: Okay. He'll begin again. Let's go over the rules of engagement one more time. We ask you that limit your questions to one question, not one two-part question or two one-part questions. Please give your name and publication, as well.
A REPORTER: Houston Chronicle. I think I want to follow up on Mr. Tetrault's last comments. I'm wondering if you can sort of tie together what the radar cross-section work needs to do to help you move to the right place, because it sort of seems like you're saying there may have been a breach either in the RCC panel itself or another fitting. I guess I'm not sort of clear where this is all pointing or pushing you now.
MR. TETRAULT: I think what's still open is a piece of RCC Panel No. 8 and/or some portion of T-seal No. 7, the one that's between Panel 7 and Panel No. 8. Those are the locations that these wires would tend to indicate that you should be looking at most closely.
In order for it to pass the two tests that there are on this ballistics, it appears, based on what we know, that it is likely to have to have an angle, it is likely to have to have a size that's more than 100 square inches. It requires that size in order to get the ballistics and it requires the angle to meet the radar signature items.
So if it has to have an angle, it probably has to have a rib. Because of the pristine nature of the carrier panel's tiles on the bottom of RCC 8 -- they look like they're new -- we doubt very seriously that, if there is a rib that it went out in space, that it would include the bottom part of the bottom panel called the spar rib. It would not include that because that spar rib probably had to be there to protect those tiles. So it would be more likely to have a side rib as opposed to a bottom rib.
A REPORTER: Florida Today. For Dr. Ride. The Rogers Commission wrote a chapter in their report about NASA's silent safety system, and I was wondering in your interviews to date after the Columbia accident how you would characterize NASA's safety system today and what role it may have played in the accident.
DR. RIDE: You're right, we did spend a lot of time during the Rogers Commission assessing NASA's safety program at the time; and it's our intent to, along with John Logsdon's group, assess the role of NASA's safety program today and see how that's evolved. We're at a relatively early stage in assessing that, I'd say. We're spending some time understanding safety's role, for example, in the disposition of foam leading up to the events and in the decision-making process during STS 107. We know that there were safety people involved in all the meetings during the decision-making process. You know, as organizationally they should have been, they were in attendance at the meetings. They didn't make significant contributions one way or another in most of these meetings.
We're not in a position yet to draw any conclusions from that because we really want to be able to take a step back and look at the larger picture; but we're trying to lay the groundwork in almost the case study, if you like, that we're putting together, that is, the on-orbit decision-making during 107 and the history of the foam events because we think that that will lay the basis for understanding how the safety program functions.
A REPORTER: Dallas Morning News. General Barry, I know you may not be ready to be specific; but I'm interested in what generally you think the interesting potential events are on ascent and this time line.
GEN. BARRY: Let me go over a couple of things. As the Admiral said, we want to get as much detail as we did on the re-entry. So here's a couple of things we're taking a hard look at.
First of all, the bipod design. The bipod itself has been designed three different times. The one that flew on Columbia was the third version. So we're taking a look at those.
The application procedures, environmental charts when the bipod was actually built, to make sure it was actually within spec.
The bipod debris. We're looking at the four previous debris problems where we have concrete evidence that it came off. There's one in question, but it looks like we've got a couple of hard to look at.
Looking at the specs for the foam to come off and hit the orbiter. The spec actually called for a .006-foot-pound impact limit on the orbiter, which is absolutely minuscule. So obviously the orbiter was not designed by spec to take hits. So we're taking a look at that.
Sally Ride's group is going to take a look at what decisions were made, as she mentioned, in the certification of flight. Also the FRR, the PRCB, and the PAR are all parts of looking to see what management decisions were made.
We're looking at the RCC aging, for the pin holes, the substrate loss. We know there was a mate, de-mate, and re-mate that was done on this.
There was crushed foamed that was identified prior to launch in the bipod region. So we're taking a look at the PR, the Problem Report that was done on that.
We've looked at the time-on-pad statistics for how much moisture was evident and any infrastructure issues. The launch out of experience the Admiral mentioned. We're looking at any and all of those, up through and including when the ET separated from the orbiter. And then, of course, the 81 seconds when the bipod actually allegedly came off.
We're looking at the MADs data, the cryopumping, the crater use, the Huntington Beach experience that was made, and the move that contributed to the crater analysis and then the spectral analysis. Finally, we're looking at the SRB bolt-catcher to make sure there's no issues there, and then finally the second-day orbital debris.
That will include a time line that will cover quite a bit. We want to have the detailed analysis just like we did for the re-entry last week and we are certainly going to include all of those and many more.
A REPORTER: And the temperature rise in the left wing?
ADM. GEHMAN: Whether there was one or not. It's not clear there was a temperature rise in the left wing.
A REPORTER: USA Today. For Dr. Ride. Since you've been doing more interviews about the decision-making during 107, can you shed any more light on what happened to the request for the imaging? You said, when you addressed us most recently, that there was kind of a tangle of relationships and discussions. Can you clarify on that for us, please?
DR. RIDE: A little bit. Since some of the information comes from interviews that were done under privilege, you know, we have to be a little bit careful about what we describe and how we describe it, as you can appreciate; but we know that there were several or a couple of different avenues where requests for photos or initiations of questions about photos arose. There was one from the tiger team that was working on this, as we discussed a couple of weeks ago. There was also questions about the possibility of photos that were initiated from people at KSC.
It looks to us, just to shed a little more light on the tangle that was this process, it looks as though the management chain heard about the requests that were coming from Florida, the questions about images that were coming from Florida, and at least in part were responding to those questions coming from, you know, not through a channel from engineers but from channels of just people who had seen the videos and were inquiring about whether photos should be taken and how to initiate the process, including making a couple of calls to DOD to ask that question.
Management appears to have been responding to those requests and saying, "Well, who's got the requirement for the photo?" Those responses were occurring at about the same time that the request from the tiger team was making its way up through another channel. So at least in some instances, the, "Well, who's got the requirement," kind of collided with the request coming up through another channel.
As a result, at least in part, the, "No, we're not ready to take photos," going back to the people asking from the KSC side came down to the engineers as a no to their request. Now, this is not the whole part of the story, but it sheds maybe a little more light on the many, many people that were involved and the way that the different roles in the organizational structure kind of played into all this. That's what we really hope to be able to tease out as we start looking at the organizational models to see what sort of useful things we can see from that.
A REPORTER: Did the MMT ever hear about either request?
DR. RIDE: It was not briefed in the MMT itself, no. The request for photos was not briefed in the MMT. Program management did hear about the desire to take photos, were unable to identify precisely where that request was coming from.
A REPORTER: New York Times. General Barry. You've been talking for weeks about doing foam impact tests at Southwest Research Institute. Have you started and, if you're holding off, are you waiting for Mr. Tetrault to tell you where to aim the foam or where is the holdup?
GEN. BARRY: Yes and no, I guess, is the answer. Bottom line is we're going to be monitoring that. It's mainly Group 3. I don't know if you want to talk to that.
MR. TETRAULT: The first testing of the foam is actually going to occur on Thursday of this week, and I think there's a second shoot that will be on Friday. That will be against tiles from a presumed lower wheel well door. We really won't get to the RCC panels until probably early June. That's because they're fabricating those particular panels. It will take a while to get them in the shape we need to get them in.
We've had great debate as to how that test should be run, as you indicated, in terms of how it should be shot, what types of instrumentation should be in there, should we only be looking at RCC panels or T-seals or both, what about the LESS structure underneath it, how do we try to get the best information about what's happening to that structure as we make these shoots with very limited pieces that we have available to us. So there's been an awful lot of scientific debate, if you will, about how best to run those tests, but they are being constructed right now and the expectation is that they will run on schedule, in June. For the RCC, the tiles will run --
ADM. GEHMAN: The testing starts this week but the testing is limited by the target, not by the bullets. We have plenty of foam. When we decided to do foam testing 30 days ago, we were talking about wheel well breaches, and so the first test rig that we built was a wheel well. That's what we're ready to shoot at. Now we're talking about the leading edge system, and it will take us a couple of weeks to build a representative leading edge.
A REPORTER: This new leading edge you're fabricating, that's from the Enterprise or what?
MR. TETRAULT: It's both.
ADM. GEHMAN: Part of it's going to be new and part of it -- we're going to do both.
MR. TETRAULT: We're shooting at a No. 6 panel which is an older panel which has had a number of flights on it. I don't recall exactly how many, but I thought it was 20.
ADM. GEHMAN: We're building up a leading edge section that's going to be essentially from Panel No. 6 to Panel No. 9 so that we can shoot at anything we want. By the time we get ready to actually shoot at it, we'll know more about what angle till we cover -- we may want to shoot at an angle that covers two T-seals and one panel or two panels and one T-seal, and we may shoot a couple of times.
MR. TETRAULT: There are significant angular differences between a panel at No. 6 position and one that's out at 8 and 9.
ADM. GEHMAN: So the limitation is the target. It just takes a long time to build that target up and get it instrumented right.
A REPORTER: Associated Press. For Mr. Tetrault. From what I gathered from your presentation, it no longer looks like T-seal 8 is in the running, so to speak, even if those pieces are not identified to be from No. 8, and that it's more now No. 7. If that's the case, do you have any pieces of T-seal No. 7 lying around and do you think that could have been the missing object in its entirety?
MR. TETRAULT: Let me answer the multiple questions here. With regard to T-seal No. 7. We do have piece of the upper half of T-seal No. 7, but we do not have the bottom half of T-seal 7. So that could be a candidate. I wouldn't say T-seal No. 8 is totally out of the picture in this game. I've found that every time you think you have an answer, you find that you've closed but you don't have an answer and something shows up that takes the wind out of your sails and you have to backtrack a little bit.
I would say it is getting more probable that the breach is a little bit further to the inboard side of the wing than where T-seal No. 8 is and we're beginning to understand a little bit of the unique features that occurred at No. 8 that led us to look at T-seal No. 8. For instance, I showed you the slag; and that may, in fact, be from a breach in No. 8, not from a T-seal. The slumping that is on No. 9, I mentioned that the bottom flange, the spar flange protected the No. 8 tiles. There is also a gap from that bottom flange at the corners of panel No. 8. That gap becomes a potential funnel that funnels hot air right at the carrier panel tiles, and that may be a very good explanation for why we have this extra slumping at Panel No. 9 is that the heat is coming out of 8, down at the bottom flange, through that gap, and is directed directly on those tile faces. So I think we're getting a better handle on why some of these pieces are unique, which allows to some degree to move a little bit to the right, as well.
ADM. GEHMAN: But I think, Roger, that it would be correct to say that a large fragment of an RCC panel is also -- as long as it contains an edge, as long as it contains a flange, that a fragment of lower RCC is also --
MR. TETRAULT: Right, a fragment of the lower RCC, the T-seal at 7, a little less likely a T-seal at 8.
A REPORTER: And the RCC fragment at No. 8.
MR. TETRAULT: That would be at Position No. 8.
GEN. BARRY: And that's one of the remaining five that we're going to test at the radar cross-section.
A REPORTER: NBC. Back off on the debris. Now, that we've been moving back and forth with the RCC panels, we're out a little further outboard. We're almost far enough outboard, aren't we, that the Maui AMOS pictures with viewing above the orbiter with the open payload bay doors, the doors eclipsed a good part of the inboard RCC panels, but at a certain point on the way out you begin to see RCC panels, the tops of them. I'm not sure exactly where --
MR. TETRAULT: I've seen that picture, and it starts at 9. We've seen from the wiring that we really don't believe we had a breach anywhere from 9 outboard.
A REPORTER: Okay. Because I've seen some interesting analysis of some of those pictures which indicates an irregularity outboard of the edge of one of the panels that could well still be a shadowing issue. It appears to be bigger than a pixel issue. It's not done by the board or by NASA but by some private work that I thought was fairly visually interesting.
MR. TETRAULT: I haven't seen that particular one, but what you saw there was only the tops of the RCC and, of course, we expect that the breach was really on the bottom sides.
A REPORTER: News 24 Houston. This question is for General Barry. In light of what Mr. Tetrault's group is finding out that it's more inboard, the breach, out of the seven test articles, which of these would still, in Admiral Gehman's words, not necessarily agree but not conflict?
GEN. BARRY: Well, two we know certainly pass through the gates, as I mentioned, insofar as the radar cross-section is concerned and the mass-to-area ratio. One happens to be the T-seal that we did, complete T-seal. The second one has to do with kind of the glove insulation inside. We don't really consider that to be a viable candidate even though it passed the RCS and the mass-to-area ratio because it's inboard and something would have to breach the RCC and then have that thing come out, which is highly unlikely.
The remaining five are probable candidates. We have got the T-seal sections that we're going to take form debris. We've got an RCC section that we're going to take from debris. So indications right now are those could be viable candidates. We've got some preliminary information this week that the mass-to-area ratio is allowed for for both the RCC segment and the T-seal segment that we're going to do. We're waiting for the radar cross-section, but those testings should be complete this week. So by next week we should have an answer to your question.
A REPORTER: Fox 7 News out of Austin. This is to whoever wants to answer it. With regards to the testing taking place in San Antonio later this week, can you explain one more time exactly what is going to be done and what do you hope to show out of it, if you can talk specifics.
ADM. GEHMAN: Well, the testing is designed to indicate whether or not a foam strike of the size and the velocity that we saw on this particular event has the capacity to damage the leading edge system with sufficient damage to cause a hole that would initiate this event. Previous foam hits, of which there have been lots and lots of foam hits, have all done extraordinarily minor amount damage to the orbiter. So the question is would a foam strike of this size produce sufficient damage to initiate the event. Even if we do create damage on the test article that is of sufficient magnitude to initiate this event, that doesn't prove it did it. It just proves it could have done it.
By the way, we have oversimplified to some degree what we're talking about here. For example, I could pound on this table with a sledge hammer and not do any damage to the table but break a leg. Same thing could be true of the leading edge system. We could hit the outside of the leading edge system and not do any damage to it but we could break the support structure, break a bolt, break a pin, in which case we would have something flapping in the breeze which might come off later.
So we're going to carefully instrument the inside of this target set so that we can, through analysis, better characterize all the ways that it could fail, not just a fracture to the RCC, even though that will be the most dramatic thing -- I mean, that would be the thing you get the picture of -- but we are going to have this carefully instrumented so that we can then infer all the ways that it could fail.
Roger, have I overstated that?
MR. TETRAULT: No, sir. That's exactly what the concern is is the fastener system.
A REPORTER: How fast will that be fired?
ADM. GEHMAN: It will be about 650 feet per second, plus or minus 25, which equates to about 500 miles an hour, which is not something you would want to stand in front of, even if it is just foam.
LT. COL. WOODYARD: Okay. We'll go to the phone bridge.
(Phone bridge not operational)
LT. COL. WOODYARD: All right. We'll go back to Houston. A question right here.
A REPORTER: Thanks for a second bite at the apple.
Houston Chronicle. Both my questions have to do with foam. A couple of weeks ago you mentioned you were going to do a film audit and see if you could track down other events other than these four major foam losses, to see if there was anything in the launch record. I just wondered if that had turned up anything yet, and I'm still curious about how you're going to deal with the possibility that the debris leaving the tank on the 107 launch was foam or foam plus ice or foam plus a piece of flange or ablator or something.
ADM. GEHMAN: We have been doing this audit of all the foam that was ever shed, and right now we have four events of known bipod shedding. Now, that doesn't mean that's all of them. As you are aware, some launches are at night and in some cases, as you may be aware, at ET separation, one of the things that the crews try to do very quickly is to jump up and take a picture of the ET as it comes off so we get a picture of that bipod foam. In some cases that didn't occur for one reason or another. Sometimes the ET rotates and the bipod area is away from the orbiter so you don't get a picture. So we don't know. There are four known cases of the bipod breaking, and they didn't all hit the orbiter. But there are launches at night and things like that. So we don't know of that.
Now, the foam audit that we're talking about refers to something else.
DR. RIDE: We have gone back and taken a look at what flights was there no visual, no ability to tell whether foam came off the bipod. From that we've concluded that, including 107, there were 5 out of 53 flights that had bipod foam loss. So in other words, on 53 flights, you can tell whether there was or wasn't bipod foam.
ADM. GEHMAN: Including 107.
DR. RIDE: The others you can't tell; you have no pictures of the bipod.
ADM. GEHMAN: Including 107.
DR. RIDE: Including 107.
ADM. GEHMAN: As far as the second part of your question, we don't anticipate mixing ice or anything like that in with the foam. The way that you account for that is, you account for it by the kinetic energy of the bullet that you're shooting. It doesn't make any difference what adds to the kinetic energy, how you add mass to it. You just vary the kinetic energy and try to replicate the strike as best you can.
There are other issues, though. There are other technical issues actually which vary the results more than was there a little bit of ice or a lot of ice. One of those technical issues is at what angle did the foam hit the RCC, did it hit it on an edge or a blunt surface. Once again, whether I do this or whether I do that makes a lot of difference; and we haven't quite wrestled that to earth yet. We might do it a couple of different ways to clock the angle around as to how it hits.
There's another technical issue, too. That is the issue of a boundary layer condition. We're going to shoot this at San Antonio level, sea level when these things come in contact with extraordinarily high speeds, there actually is a factor of cushioning caused by the air, which does not exist at 160,000 feet. So we also have to figure out how to account for that also.
That's why this design of the test has taken so much time, because we think we're only going to get a couple of shots because of lack of test articles. Once you hit a test article like this, it's probably irrelevant to hit it again because you've done so much damage to it. So we are taking a considerable amount of time to design the test.
GEN. BARRY: To follow on to the question of what is the makeup of the actual debris hit. We're not counting on it and it doesn't look like it's going to lend itself to a concrete answer, but spectral analysis is still ongoing on the film. We only have three colors that we can really discern that aids in the determination of what is the make-up of this thing. Obviously foam, the ablative material that was underneath the bipod, if there's any metal that might have come off of that, we're hoping, if anything, that the spectral analysis might give us a clue, but it's going to be very limited at best and the indications right now is it's not going to be very helpful. We're still not concluding yet on that, but we're hoping it's going to give us an answer.
LT. COL. WOODYARD: We're going to try the phone bridge one more time.
(Phone bridge not operational)
LT. COL. WOODYARD: Okay. We're going to pass on the phone bridge. We apologize. It's not working today.
A REPORTER: Florida Today. Probably for Admiral Gehman or maybe General Barry. Y'all mentioned that you're really initiating an inquiry into the ascent and putting together a detailed time line. Of course, there's the foam event at 81 seconds. I think Major General Barry had mentioned a gimbaling of the boosters around 62 seconds in response to an I-load. I wonder what else have you found out there in terms of the ascent and how this all might play into the whole big picture in terms of your investigation.
GEN. BARRY: Well, any single event you can't conclude is the most determining. So there's going to be a series of issues here that we're going to try to put to bed.
First of all, as I mentioned, when you talk about the foam, it is the application and the voids and figuring out what the design element as well as the application was concerned. The mate, de-mate, and re-mate, how much that got shook. Then there was a crushed foam issue that was identified prior to launch.
Then we have on ascent. It looks like three out-of-experience issues here. Now out of experience is out of spec. It's not out of tolerance. It's not even out of family, using NASA's terms. One certainly is a 61 seconds. We're still trying to run that down because we see this as a solid rocket motor movement that is well within the capabilities of the solid rocket motor but it is right at max dynamic pressure to see if that is. There's an indication from MADS and a few other things that there might be something at the beginning of launch and then towards the end, when the external tank separates. We're still trying to run that down. So I qualify that as out of experience, not certainly out of spec or anything else.
Now, if you add all these combinations, including the cryopumping, can you arrive at the point where the bipod separates from the external tank? What we're trying to do is say what, if any, of those incidents contributed to that single event. So we're going to run down each one of these as we hopefully get to a concluding point, and then we'll provide that in a report.
LT. COL. WOODYARD: One more question.
A REPORTER: Associated Press. (Barely audible) Along the same lines the ascent data from the OEX sensors on pressure and temperature blips that were unusual in the noise. Do you have any other words on that?
ADM. GEHMAN: That is exactly why we've announced this technical review with the same degree of detail that we have done on the entry. We have previously reported that nothing on ascent jumps out at you. On entry -- this is from the OEX MADS recorder -- on entry we had a couple of things that jumped right out at you. So we reported them right away.
Nothing on ascent leaps out at you as being startling, but there are some things which are going to bear close scrutiny. So I think really we've got to leave it at that point. What we said earlier remains today: Nothing on ascent jumps out at you. Nothing is out of spec or nothing went off line or rose or anything like that, but there were some little squiggles and things like that that we want to be sure that we account for, more from a point of view of completeness than anything else. More from a point of view of leaving no stone unturned that we think we can find something.
One of the reasons why this is coming up now is that the OEX recorder provides us more information, more relevant information to ascent than really the telemetry does -- for example, all the strain gauges and things like that. So if there was a period of max dynamic loading and things like that, you might see it in the strain gauges. So we have a lot of things we have to add up together. It's really premature to speculate that there is anything there. We really are doing this from the point of view of not missing anything rather than we smell a rat or something like that.
LT. COL. WOODYARD: I'm told the phone bridge is up. Can you hear me now?
A REPORTER: CBS. This is a question for Roger Tetrault. I just want to make sure I absolutely understand something. You were talking about the pattern of the slag blow-back, for lack of a better word I'll use. I assume what you were saying, in trying to visualize the geometry, that that was consistent with a plume entry into the bottom half of RCC 8 that then hits the spar, causes some kind of melting damage, and blows some part of that back onto the inner surface of the RCC as it burns through the spar. A, Is that correct; and B, does moving slightly inboard change anything with respect to the border of the cable bundle that burnt through that were running on the outboard side of wheel well as you ultimately got into the wheel well itself.
MR. TETRAULT: With regard to the first one, you have, I think, correctly stated it except for the fact that it probably hit the Incoflex before it hit the spar and that was the first deposits that were made to the back of the RCC panels.
With regard to the cutting of the wires along the wheel well. Actually by moving a little bit further inboard, you actually close the distance between those wires that were cut on the spar versus the wires that were probably cut along the wheel well, and that makes it even more possible that the sequence works properly.
ADM. GEHMAN: By the way, all this has to be confirmed by a thermodynamic analysis, too. We've got all that work to do to see whether the temperatures and the times match up. So lots of work to be done here.
A REPORTER: Los Angeles Times. This is for Admiral Gehman. As you've held these various hearings, you've gotten a number of recommendations about what would improve the safety of the shuttle system and the management system at NASA. I noticed that today you mentioned that you had had some meetings with members of Congress and you're going to have some additional ones. I'm wondering if, as you begin to deliberate about your findings and then your recommendations, whether fiscal realities will play a role in what you can recommend and, as part of that, if you could address whether you have requested or received any sort of cost briefings on what it would cost to implement certain kinds of changes that you might feel would be constructive. Thanks.
ADM. GEHMAN: The answer to your question is: We will not be constrained by costs. We probably would avail ourselves of technical information to determine whether or not one of our recommendations was even possible or even relevant or whether or not it was even humanly possible. Indeed, we may make ourselves aware of what things cost; but will not be constrained by costs.
If we come up with a series of recommendations which we believe would be prudent in order to continue safe manned space flight in the space shuttle vehicles and it ends up being too expensive for the nation to bear, so be it. It's someone else has to make that decision.
LT. COL. WOODYARD: Next question on the phone bridge.
Okay. What we'll do is we'll conclude today's press briefing. As always, our board members will remain for a brief period to answer any additional questions from Houston. Thank you all for coming.
(Conference concluded at 2:14 p.m.)
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