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CAIB Press Conference Transcript March 4, 2003 (Part 2)

Status Report From: CAIB
Posted: Tuesday, March 11, 2003

Part 1 | 2

ADM. GEHMAN: Let me make a comment here because I saw a couple of you shaking your head at one of the things that Mr. Tetrault said during his statement. It gets to this question. Right now we've got all these random pieces and we're seeing all these marks and chars and destruction. It will be useful to us when we get an identical piece from the right wing and the left wing and we can see there's a difference in how they looked. For example, if we did a right wing elevon and it has certain marks on it, we might attribute those marks, as Roger has said, to the normal effects of the vehicle breaking up and this piece entering the atmosphere. Then we look at the left elevon and it has all those things plus other marks. It's the "plus other" ones that lead us into the investigation. So until we get a couple of identical pieces -- that's why the tires are important. We have all six tires now and we have two of the landing gears. We have the complete nose landing gear, complete, and pieces of the others.

MR. TETRAULT: We have pieces -- that piece that we found of the strut, we are fairly certain now is, in fact, from the left side. The upper strut, that we have no certainty of exactly which side it came from and may never have certainty.

ADM. GEHMAN: But it's the comparative analysis which will be able to help us answer the questions you're asking. Right now we just don't know.

MR. TETRAULT: Let me give you one comparison. As I said, if you look at the debris from the right side, you can see that there is significant damage to the right side from reentry. We see the black deposits on the right side, not to the extent that we see it on the left side but it's on the right side as well, which means you had molten aluminum being sprayed or deposited onto those tiles on the right side where the event was not occurring. That's a very hot reentry.

A SPEAKER: ABC News. Can you tell us a little bit more about this picture of debris of tiles that came from the left main landing wheel rear door last week and what does the damage on that tile tell you about how the heat may have circulated and how temperatures may have evolved?

MR. TETRAULT: Let me talk to two of those things from last week. I think first there was the Lubbock tile, and it looked like it was almost heat coming up underneath that tile. One of the things that we observed when we went down there and started looking at a lot more tiles is that a lot of tiles looked like that. In fact, that seems to be the way that they fracture and the way that they remove themselves from the skin of the aircraft. They leave a piece of the RTV and the felt pad behind and a piece of the tile and they kind of break out in a conical section. You can almost take some of those tiles and replace them over the top of this cone that you see. I feel certain at some point we'll actually find one that matches. So the Lubbock tile is a little bit less interesting than we started out.

The other piece which we talked about last week, which was the left inboard wheel well frame on the forward side had an area in the aluminum frame which looked like air, very hot air, was blowing out of the wheel well and laterally across the normal air flow. So it would be 90 degrees perpendicular to the air flow. We've added two subsequent pieces to that which have now given us the entire frame of the inside door well, which I mentioned to you we now have, but we have no pieces of the door itself.

I would also like to say that as we look at this and try to analyze what's happening, it's going to be equally as important to recognize what we don't have as what we do have, because the stuff that started coming off out of California and Nevada and Utah we're not going to have unless somebody finds it out there. That, in fact, is going to be some kind of a clue as to where the breach occurred.

A SPEAKER: Associated Press. Mr. Tetrault, in your list of items that you discovered and analyzed, I'm wondering which offers the most encouragement to you in the pursuit of the piece you're seeking, which piece is particularly tantalizing.

MR. TETRAULT: Well, the ones that are just interesting and one where we're in a kind of purely speculative situation is the slag on the RCCs and how does it blow forward and how do you get the stainless steel and aluminum up onto the front and back edge, if you will, of an RCC when, in fact, that stainless steel is behind the area. So that to me is a little bit intriguing and something that we'll have to spend some time. I think the question that was asked about that panel where it appears to be blowing out and going laterally, that may be a late event. It may have something to do with the tires. We don't know at this particular point, but as we read these things eventually, I think we'll get answers to these questions.

A SPEAKER: New York Times. A question for Mr. Tetrault and Mr. Wallace. Looking at these E-mails that bounced around at various levels, this may be a cultural issue. Mr. Tetrault, you have long experience in the nuclear field. There are nuclear near-misses where there were lower-level people who did not bounce things up who may have had cultural reasons not to do it, were afraid of repercussions, afraid of losing their jobs. Have you gotten to the stage of looking at the culture of NASA or looking at whether there's a written procedural flaw here that prevented this from rising to an appropriate level?

MR. WALLACE: I'll give Roger a brief break. No, we haven't, but I also think that that is something that Admiral Gehman is probably going to charge the players-to-be-named-later group to look at. As I say, we will be running those E-mails to ground, getting the whole sort of factual story clear and interviewing all the people who are in that decision-making on-again-off-again process to understand what they decided and why. You know, I think, beyond that, in sort of the more root cultural management issues, that's actually a topic which is somewhat shared across the board and I think also expected to be given to the new group.

MR. TETRAULT: Can I finish that question? You brought up the nuclear issue, and obviously I come out of that side of the field. I've seen a number of articles which have asked why are there so many nuclear guys on this group, not only in the board but underneath at some of the levels. My own personal opinion is the nuclear has a history and because of that history it had to adopt certain attitudes and qualities over the years and particularly a questioning attitude about prove to me that it's right rather than I assume that it's wrong. And I think to some degree Sean O'Keefe saw the nuclear Navy as having some of those attributes that he probably wanted on this board to look at those kinds of things. I know in certain things I have looked at, I'm a little bit suspect of that questioning attitude that should be there that I'm not seeing. It's not in all areas obviously but in certain select areas.

ADM. GEHMAN: Steve Wallace replied exactly the way I would reply. In my calls on the oversight committees last week, I assured them that all of these issues about management and culture and history and oversight and lessons learned from previous studies from Challenger, we're going to get to that; but you've got to remember that at this point in the Challenger investigation they knew what went wrong. So the review of who did what to whom and who did his job well and who didn't do his job well was relatively fairly focused. I'm not really interested in casting about NASA to look for everybody just without any particular focus or without any reason, just casting about and casting some chill over NASA that we're searching for everybody who parked in the wrong parking place when they came to work this morning. So it has to follow either a deduced fault or an actual direct fault that we find. We will then do a complete review of all the aspects of the history and culture of NASA, getting into all those issues, but it has to follow a logical order.

Now, we're going to conduct our review through these management boards and committees and all those kinds of things in nice due process, but you've got to remember we're not following any particular fault here because we don't know what happened. With that caveat, yes, we're going to go after all those things.

A SPEAKER: CBS News. I think for you, Mr. Tetrault, two things about what you were telling us. I've never understood the telemetry of wheel well temperature rise rates in the context of an actual burn-through in the wheel well. I've never understood how the plasma could be in the wheel well that you wouldn't see more radical telemetry. Have you got a better sense of how something like that could happen that you wouldn't see more telemetry? The other thing is when you're telling us about the aluminum and the coating on the right and left, does anything of that tell you anything about the attitude of the vehicle in that last 25 seconds or 27 seconds before the final off the signal? Do you have any sense? I'm guessing what you're telling me is this thing could have going sideways or whatever and you're seeing the kind of natural flow you would have before it broke up.

MR. TETRAULT: I'm not sure I'm going to answer your question very specifically. With regard to the attitude and the telemetry, let me say this. I'm having difficulty with some of the off-nominal timings, as I mentioned to you. One of the reasons I'm having trouble is it's very simple physics. There was a Temperature A, brake line hydraulic fluid Temperature A that went up very early in the event. It was either the second or the third one that went off nominal. Temperature B, which sits about 2 inches away from it, did not rise until about a minute and a half later, whereas Temperature C which is probably 6 feet away and Temperature D which is 4 feet away were all rising off nominal. That doesn't make a lot of physical sense to me. What we find as we look at these temperatures is that it appears to be a straight line up and at some point NASA has called it off nominal and there may be some variability in where that call is on where it is off nominal. So what I'm trying to tell you is if you're trying to put together a time line, I think you can be fairly certain when it went off line; but when it says it's off nominal, I think you're going to have to take that with a little grain of salt and eventually you may find, as we build that time line, some shifting of these sequences around to some degree. Hopefully that answers your sensor question.

The one with regard to attitude, if you look at the sensors themselves and telemetry, it is interesting to note that all of them were going up off nominal but then they went up in a very, very sharp fashion as soon it rolled into the left-wing-down attitude. I won't say anything more, but it's interesting to note that that occurred that way.

A SPEAKER: Orlando Sentinel for Mr. Tetrault also. As you step back sort of just to sum up some of these earlier questions and look at the evidence you've accumulated so far, in your opinion, does it seem to be moving more towards a breach in the leading edge or a breach in the wheel well?

MR. TETRAULT: I think those are both equally alive. Everybody has their own theory. I'm sure each of you have your own theory. Everybody on the board has their own theory. I'm going to be patient and not express my theory at this time.

A SPEAKER: Houston Chronicle. I wonder if you could bring us up to speed on the foam story, what you're looking at now, if you're any closer to where the foam debris struck the underside wing, whether it was one or more pieces.

MR. TETRAULT: I really don't have a lot more to report other than what you have already heard. I do know that earlier this week that NASA is trying to develop a variety of experiments where they can look at cryo-pumping and some of those kinds of things in small-scale experiments where they can look at how well does this adhere and what is the likelihood that something would come off and so on and so forth. We reviewed that test plan earlier this week and gave them permission to go ahead and run that test plan. They also wanted, as part of that test plan, the authority to chop into a bipod, starting with the right bipod on external tank No. 120, which is very light weight but has the same configuration you would find on the 93 that was on the OV 102. We have not given them permission to do that and cut into it until they come back to us and tell us the results they got on the initial test plan.

ADM. TURCOTTE: To walk that backwards, there is another tank, ET94, I believe it is. It's a sister tank. We're looking back at the process, when that was put together, what were some of the process flows that went into that, were some of the propellant was changed at certain process points, some of the epoxies were changed. We're looking at all of those to figure out in many ways, if it did separate, how much did it separate and why did it separate, what lot number of the paint was used and what lot number, et cetera, et cetera. So it's just much more than just looking at the photos. We're trying to what-if. If there were some failure modes present, what if, how much would come off and when.

MS. BROWN: We'll take about four or five more questions here.

A SPEAKER: CBS News Radio. This is kind of an accounting question, so I don't know which one of you wants to tackle it. Could you clarify the most recent significant debris finds in the last week or so, what have been the most significant pieces, and also can you just reclarify your westernmost find, what it was and where it was again?

ADM. GEHMAN: The westernmost find is still a fraction of a piece of tile. It's not a whole tile. It was found in the area of Littlefield, Texas, which is well west of Fort Worth, as you know. We don't have a picture of that piece of tile. It's only a fraction of a tile. It's just now being inducted into the system. And I think Mr. Tetrault has already gone over his favorite piece several times. Certainly the landing gear, the wheels are very significant, but you're never sure when the golden nugget is going to show up. So it's hard to say what's significant.

MR. TETRAULT: A lot of times it's a very overlooked piece initially.

A SPEAKER: I guess I was trying to get a time frame. I'm sorry. Were those found during the last week is what I was getting at.

MR. TETRAULT: Not necessarily. The stuff we're continuing to find is mostly fairly small things. My understanding is what's happening in the field is most of the big stuff has been found and we are finding lots of screws and bolts and tile and tile pieces and those kinds of things which continue to come in, but we're not finding many of the really large things. That's just hearsay, if you will, about what they're finding in the field.

A SPEAKER: Newsday. I'm still interested in this aluminum spray. I'm wondering whether this flow that you mentioned that was 90 degrees to the flow of the air, was that flowing from the left wheel well toward the right side of the craft, and is it conceivable that could have been some aluminum in that.

MR. TETRAULT: No, it actually appears to be the opposite of that. It appears to go from the inboard left wheel well frame toward the left wing tip.

A SPEAKER: Can you say anything about what the mechanism might be to get that spray across?

MR. TETRAULT: None whatsoever.

ADM. GEHMAN: The flow, I don't think it's molten aluminum. It's not aluminum. It's a discoloration which seems to indicate a heat flow. It seems to flow from the left forward inboard side of the wheel well towards the fuselage.

MR. TETRAULT: I'm going to agree with the admiral because that's the side that the tiles are on.

ADM. GEHMAN: That's correct. Now, what does that mean? Stay tuned.

A SPEAKER: USA Today. Can you give us any progress report on the two or three or four different analyses going on with regard to trying to locate the breach or the thermal analysis, the aerodynamic analysis and whatever?

ADM. GEHMAN: I can tell you that the studies that we mentioned last week, which were kind of thumbnail studies, are now getting to be a little bit more sophisticated. Some of the things that we thought they would show us are now being challenged by experts, but we are still trying to do what we call a fact test. And Roger mentioned this two or three times. We're trying to find a scenario which fits the temperature readings. And we are inducing holes and we are inducing heat flow into the vehicle in various places and we are more sophisticatedly modeling how the heat flows in through all the little openings and cubbyholes and things like that. We don't have anything to tell you on the conclusion side. All I can tell you is that the analysis is getting more sophisticated and we're doing more of it.

Same with the aerodynamic analysis that Dr. Widnall is working on. We're trying to get smarter about that. The only thing I can tell you about the aerodynamic analysis is that even though the vehicle -- even at the time of the final two seconds in the extra 32 seconds after the loss of signal, the vehicle's attitude and position was correct. We do believe that the vehicle was fighting forces more strongly than we -- the fight was getting a little more vigorous at that point and we also believe that the beginning of some of the control measures that the vehicle was taking to maintain its attitude started earlier than we previously thought. So we're down now to it's a little bit more refined. So it looks like the vehicle was fighting aerodynamic flow forces a little earlier -- I'm talking seconds, not minutes -- a minute or two earlier than we previously thought. Little tiny deflections that we hadn't noticed before. But I can't tell you anything more about localizing or anything else.

MS. BROWN: A couple more questions here.

A SPEAKER: On the debris issues, we were told last week that the cassette that was shown last week was recovered near Palestine and the press reports I've seen on the other crew module contents being found further east. Was the debris spread from the crew module indicating that this cassette was unusually upstream, or were crew module materials spread out on a much larger area?

MR. TETRAULT: All the crew module debris is kept in a separate location that's in the same hangar. I haven't a spent a huge amount of time there because I've been concentrating on the left wing. I don't know exactly at this point where any piece of debris has landed. We have asked for that information; we have not received it. For us to analyze and go backwards and try to say where did the heat come from, we have to subtract out all of the reentry heat, if you will. And in order to do that what we need to do is find out where the debris landed, then try to get a ballistic coefficient from that and back it into the sky and say it left the aircraft here. That's part of all the analysis that we have to do. So my realistic answer to your question is: I don't know.

ADM. GEHMAN: I'm the spokesman on crew issues. Because of the sensitivities to the families and things like that, we are conducting that examination pretty circumspectly and anything that we learn -- if we learn anything that's unique or special from the crew debris, the crew module cabin or anything like that, we then carry it over -- we take it over to the curtain and put it out on the floor. So far nothing remarkable has come out of it. The cassette was located kind of in the primary debris field, and it was kind of in the same area where lots of stuff was found. So nothing remarkable about it was found.

MS. BROWN: One more.

A SPEAKER: CNN. Have we found more of one side of the vehicle? Do we know a percentage of which side we've found, a 60/40 percentage? And the tile that we have identified, are we going to be able to identify what part of the vehicle it was from and how that process happened?

ADM. TURCOTTE: I just left there yesterday. I spent about five, six hours yesterday and the day before. It's pretty evenly split, and not all of what we have is there. For example, we don't have the hydrazine tanks and some of the other vessels that are in there. They're in a separate location. So not all of what we have is there. As a broad brush scope, most of what you see is kind of a scattered range. If you were going to take a shot gun, it would be a good analogy to that. Again, a lot of what you see there is also stored on the left-hand side. Those are still for further processing. So as they come out and they're identified, it could come to take shape a little better; but right now it's pretty much of a general scatter.

A SPEAKER: The Los Angeles Times. Mr. Tetrault, you mentioned an interesting point that it's important to recognize what you don't have as well as what you do have and the importance of that. Given that you have most of the frame of the landing gear door but not the door itself, does that support the notion that the door might have been damaged or even been dislodged fairly early in the accident and also, if so, might that have anything to do directly with the trauma that has now been recognized in the tires?

MR. TETRAULT: At this point I would say it's just an interesting observation and I wouldn't want to jump to any conclusions about what might have caused us not to find the landing gear door. I think at some point we'll be able to answer that question, but I think it's way premature at this point to speculate on it.

ADM. GEHMAN: Our job is to fit six or seven of these investigatory themes together into a pattern that fits. If, for example, the thermodynamic investigation indicates that the loss of a tile would not have induced enough heat to show these kinds of things, if heat had to be introduced directly into the wheel well, then the door becomes very interesting. So these things all have to fit together before we can answer any of those questions. Right now they don't fit together, not that we can see.

MR. TETRAULT: But we do have some interesting tools. We know when various metals melt. So when we find deposits, we can get an idea of heat. We know that the core bond that's used on the aluminum skin begins to degrade at about 400 degrees. The RTV degrades at 500 degrees. All of these things we can put into a pattern as we look at this debris and try to figure out what was the cause, where was the heat coming from, and how do we back into it.

MS. BROWN: I think we had a couple of questions over here. Two more. Go ahead.

A SPEAKER: Dallas Morning News. Just listening to the general conversation here, it sounds like you people are dramatically farther along this week than you have been in the past. Would you characterize it that way, and does it mean anything for the speed with which you might reach a conclusion?

ADM. GEHMAN: Well, I would characterize this week as a very good week because we have so many independent investigations going on which are beginning to lead to little tidbits of information. The problem is that since we don't know where we're going, we don't know how far along the road we are. I think Yogi Bera had a saying, something about if you don't know where you're going, any road will do. That's kind of where we are. We're investigating everything right now because we don't want to leave any stone unturned. Yes, I would characterize this as a very, very good week because of the travel and the investigations that you heard reported by these officers, plus you multiply every one of these guys by six or seven and you realize how many things are going on here at the same time.

A SPEAKER: Aviation Week. Has the work in the last week on the ground-based photography shown anything provocative beyond last week? Secondly, as you look for this debris in the coming two weeks or so in the world of black-box type retaining data or cameras retaining imagery, what are some top priorities there?

ADM. GEHMAN: The photo imagery continues, but there's nothing new since I reported last week. The photo imagery shows debris shedding over California, which surprised me how early it showed debris shedding, tiny little pieces which probably never made it to the ground or, if they did, we aren't likely to find. The larger pieces of debris that were shed early, thanks to the NTSB and the FAA and military, we've tracked several of them all the way to the ground. Those are the ones that we're asking the local sheriff to go out and look in this spot, we're pretty sure there's a piece of debris out there. Unfortunately, the weather's been bad, it's covered with snow and things like that. So the answer to your question is, no, the analysis of the photography continues but nothing remarkable to report there.

We continue to put a high emphasis on the recovery of anything that has data, anything that stores data. It turns out that there are literally dozens and dozens of pieces of equipment on the shuttle that store data at one part or another. As we come across them, just like we did with the crew tape, after we finish, we're pretty sure that we've analyzed them and we've taken anything sensitive out of them, we make it public as soon as we have it. And there are no black boxes on the shuttle.

A SPEAKER: I meant generically.

MR. WALLACE: Right. There are no black boxes and flight data recorders. Of course, with the telemetry, they're actually in many respects way ahead of the civil aviation sector in that area. I would say, as far as cameras, there are three cameras which photographed the external tank separation right in the umbilical tube. These cameras are the ones you may have seen on past missions, extremely high-resolution photographs of the external tank separating. Unfortunately that requires a return to earth of the film. So it would be something we would love to see, but I don't think we're optimistic.

ADM. GEHMAN: That might possibly show the famous left bipod ramp. That's why we would like to see that.

MS. BROWN: Thank you very much. I want to apologize to the folks on the phone bridge. Someone had a phone ringing, and so we had to shut you down. Call us, and we'll answer your questions. The board members will stay around here a little while here to answer some further questions for you guys.

(End of conference, 2:16 p.m.)

1. Should indicate Admiral Turcotte is on Group No. 1
2. Should indicate two non-NASA people will appear
3. Should indicate SIAT
4. Should indicate it's called the Shuttle Independent Analysis Team



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