Columbia Accident Investigation Board Press Briefing
Tuesday, March 11, 2003
1:00 p.m.
Center for Advanced Space Studies Lunar and Planetary Institute
3600 Bay Area Boulevard
Clear Lake, Texas
* See errata notes at end of transcript
MS. BROWN: Is everybody ready? For those of you who haven't been here before, we'll have each of the board members give a presentation about what their group is working on, after the Admiral speaks. Then we'll save all the questions to the end. We'll take some questions from here, and then I will take some questions from the phone bridge, if they are still active. Ready?
I'd like to introduce Chairman Hal Gehman.
ADM. GEHMAN: Good afternoon. I'm joined today by three of my colleagues on the board, one representing each of the subboards or working groups that we have established. To my left is Ken Hess, who is working in the operations section. Beside him is John Barry, who's working in the section that's looking at material and maintenance issues. To his left is Dr. Sheila Widnall, who's working on the engineering and technical relations section. I'll make a few comments, and then each of them will make some short comments as to what their groups are working on and where their fellow board members are. Then we'll open it up to questions. As is our practice every week, we try not to save up news for Tuesday. We release things as they become apparent. The purpose of this press conference is really more of a dialogue so you can ask questions and get a two-way dialogue going with the board members on anything that you're interested in.
Once again, I think that we've had a good week here. We are moving along methodically in our understanding of what happened to the orbiter. That is, let me rephrase that. We're moving along nicely in our understanding of the forces that were at work when the orbiter as it failed to properly enter the earth's atmosphere. I would not want to say that we're moving along rapidly at finding the cause, because it remains elusive; but we are doing a considerable amount of good, hard engineering and science work at understanding the environment and the forces the orbiter was subjected to and also narrowing down the part of the geography of the orbiter where the assault seems to have taken place. Every time we do a little analysis, every time we see another study, it tends to focus us a little bit more; and I think that my colleagues here will talk about that some more.
We continue to rely primarily on the six major detective stories that I told you about before. They are the aerodynamic analysis, the thermal analysis, the videographic and picture analysis of debris shedding, the refinement of the time line, debris collection layout and analysis, and the material documentation of everything that was done to the orbiter or anyone who touched the orbiter in between its flights. Those are the six primary areas that we hope will lead us to an answer to this riddle, and a lot of work has been done in each of those areas.
The board this week as a group spent a lot of time, many hours this week, testing, proposing, and discarding scenarios. Now, by that I mean individual little pieces of scenarios, relatively detailed discussions. The purpose of these hours that we spent together was not necessarily to find the scenario that caused the orbiter to fail. We're not smart enough to do that yet, but we did want to determine what tests would be necessary in order to either prove or disprove a scenario. In other words, if somebody has a theory or a scenario which seems to be relevant, then we want to develop what it takes to either prove or disprove that. So we went through that. We spent a considerable number of hours going through that process. We don't have an answer for you, so I won't go into any more detail than that.
The public hearing I found to be very useful. We're going to continue with the public hearing process. The next public hearings are Monday afternoon next and Tuesday morning. We are going to go for three or four hours on Monday afternoon and go for three or four hours on Tuesday morning here at JSC. It's actually going to be at the Clear Lake Hilton Hotel in one of their ballrooms there. We're going to discuss investigatory matters. We're going to have some of the experts on thermo and aero analysis come and brief us with charts and view graphs and movies and videographs as to exactly where they are. So you will get a postgraduate-level education on aerodynamics and thermodynamics so you will see, be able to tell at the end of that exactly how far we've gone, how deep we've gone, but also how far we have to go.
Another issue that the board worked very hard this week was the issue of debris testing. We and NASA had several meetings. The board has some testing initiatives that we want to get started. Just laying the debris out on the floor is not enough to find the answer to this mystery. We need to do metallurgic testing. We need to do heat testing. There's a whole series of tests that need to be conducted. At the same time, we have to be very careful that we don't in any way disturb or remove anything that might be evidence. So this has been a very careful and methodical process between us, NASA, and the people who are helping us, like the NTSB and other people who are helping us like that.
The last thing I'm going to mention is three new members that I announced last week. Dr. Sally Ride has already been at work. She was here last week and has already made a significant contribution. Dr. Douglas Osheroff I've been in contact with. He will be visiting us this week. He already has a bunch of ideas that he wants to pursue. Dr. John Logsdon and I have exchanged a couple of telephone calls and E-mails, and I will be meeting with him next week. So all three of the new board members are either on or already participating either in person or by remote, and essentially from now on they will be coming and going essentially weekly, if they can, to participate and help our investigation along.
That's a quick summary. Let me throw some facts out, just some facts and figures. As of close of business last night, we have collected 28,286 pieces total that at Kennedy. We've collected thousands more than that. Kennedy has 28,286 pieces, of which 25,404 have been identified. Now, when you see pictures of the floor and you see pictures of the grid, that represents only 1,038 pieces of the 25,000 because you have to remember that we are laying the orbiter out in two dimensions, not three dimensions, upside down. So what we're interested is the bottom surface. So those are the 1,000 pieces that we have out there – the landing gear, the landing gear door, the tiles, elevons, and things like that. All the rest of the pieces are cataloged and stored, and they are available for us to use for analysis.
The 28,286 pieces represent 39,300 pounds – I haven't divided that into the dry weight, but it works out to something like 18 or 19 percent. On a daily basis, every day of the week, there have been over 4,000 people out collecting debris. On one day last week – I think I'm looking at the 7th here – they had actually 5300 people out on one particular day. They continue to average a dozen aircraft a day, helicopters and fixed-wing. The Navy team in the two lakes, the Toledo Bend Lake and the Lake Nacogdoches, have identified over 200 submerged targets which are of great interest, by electronic means, by sonar means, and then they're going to go back and dive on them. We're hopeful that included in there are the main engines. I think that that's kind of all the – oh, among the 1,038 pieces laid out in the grid are 233 that are from the left wing, which, of course, is what we're most interested in. I think that covers all the introductory things. I'll pass it now to General Ken Hess.
GEN. HESS: Good afternoon. Group 2 is continuing on its marks through the basic processes that got the shuttle into launch and have to do with training and payload and operations. If you recall from our previous sessions with you, we kind of described our approach as kind of in phases. We're, I would say, maybe two thirds of the way through Phase 1 that's just understanding and appreciating all the processes that lead to a launch. This last week we finished looking at the training and certification as well as a complete research of the impounded records that NASA had on hold for us. In the payload area, we've completed our documentation review and we looked at the telemetry that had to do with the payload and everything that was downwind to NASA; and we didn't find anything that was unusual in those areas.
In the areas of operations, we are continuing our look into the DOD request for imagery. We are sharing that with Group 1, and also with Group 1 we're looking at E-mails that were exchanged between engineers as well as looking at the impounded records and logs of the mission control center at the time. And this last week saw us begin our initial sets of interviews with the astronaut office.
In the area of mission management, we've started to take a look at NASA's organizational structure and those actions and decisions that led to launch preparation and launch decisions as well as the things that took place while the shuttle was on orbit; and we'll begin taking a look at the MMT, specifically its organization and performance, here in the coming weeks, with the addition of Dr. Ride to our team.
Last week I had the opportunity to go to Kirtland Air Force Base as part of the Air Force research lab and go to the Starfire Optical Range. If you recall, they took the picture of the orbiter overhead where people have been suggesting perhaps that there was leading-edge damage that was in that picture. We're trying to verify that. I went there because I wanted to understand the techniques that were used to take that picture and also to find out what kinds of things that had been done to enhance that image by the Department of Defense.
Now, I must tell you that those photo experts are just now beginning their work in liaison with aerodynamics experts and plasma experts to try to see what the picture will really yield. So the important part right now is to enhance the photo as much as can be done without adjusting the facts behind the photo. We have an excellent team that's working that process right now.
The team added two new members. Admiral Gehman mention Dr. Sally Ride. She's going to be joining our team and she's going to concentrate mostly in the flight readiness review and certification processes as well as pinch hitting in other groups and areas where she has expertise. We are also adding tonight Dr. Tracy Dillinger who's a human factors and organizational psychologist. If you look in the McDonald's independent assessment, you will find that she was part of the human factors group in that particular report, as well.
In the very near future, we're going to be attending an integrated simulation training between astronauts who are preparing for a mission and their ground team so we can look at all aspects of that training; and I think that will be probably the last piece that we will look at as far as active training processes.
We are beginning to outline our approach to taking a look at the safety organization and processes, in the next week or so; and then several members of the team will travel to DC this next week to begin interviewing at NASA headquarters those people who are in our area of responsibility.
Dr. Dillinger and many others who are already on the team, to include a Ph.D. from the NTSB, will join us in coming together with a strategy to begin looking at human factors. I think everybody realizes that our whole investigation will fall short if all we do is concentrate on the technical aspects and ignore the organizational dynamic. As you recall, Dr. McDonald last week says he has great confidence that the management would make the right decisions if they had the right information. So we're going to take a look at the organizational dynamic, with an attempt to try to understand the implications of what Dr. McDonald was telling us.
Our goal still remains mishap prevention by identifying the hazards and coming up with risk mitigation strategies that would be helpful. So we'll look at the processes and talk to the personnel both in maintenance, with General Barry's group, and on the operational side with Group 2, and then work the seam of that issue together. And in the coming weeks we expect to finish Phase 1 and then basically use safety and the human factors processes, being our Phase 2 approach to the overall investigation. Thank you.
GEN. BARRY: Good afternoon. As a member of Group 1, right now we have General Duane Deal who's out at KSC right now. Admiral Turcotte will leave tonight to go to KSC. We'll follow up that with visits to Michoud and we're planning to also next Tuesday visit the vendor for the RCC and also follow up with General Hess' group when we head up to the headquarters at NASA to do some interviews.
As you remember, our group is responsible for maintenance, materials, and management. Human factors kinds of considerations also. We've got a number of subteams up right now. They are going out and continuing their investigation, at least two to three key investigators for each subgroup. I'm going to give you a couple of updates on maintenance and then I'm going to follow up with material. So let me just cover the maintenance area.
Closeout on fault trees is progressing at a pretty good rate. We continue to work the issues that will eventually be categorized as non-factors. To date, we are closing out on the fault trees probably in about a week. There still has to be a formal presentation to the board, but we expect to see the SSME, the space shuttle main engine; the SRB, the solid rocket booster; and the placement on the solid rocket motor. So we expect that probably to be done in the next couple of weeks, and we'll give you updates as we go along there. Nothing's been finalized yet on the closeout, but right now to date that looks like a pretty good schedule. The external tank will take a little bit longer because right now there are 14 working groups and about 3200 blocks on their tree. And, of course, the orbiter. So we still have a little more to do on that one. So that's the update on maintenance.
Let me just turn to material. If I could have the first slide, please. I'm going to show you a couple of slides here, some of which you have seen before. And, Woody, if I could have you come down and just pick up. This is the bipod that I think you've seen before. Right now we're trying to follow the foam. And here is the connector, as you can make the comparison between what the slide has and what we have that Woody's holding in his hand.
I will also tell you that as we follow the foam, we're also looking at the fact that ET 93, which was the external tank involved with Columbia, was mated, de-mated, and then re-mated. And there was a problem report generated on that, on damaged foam, which is not unusual when that happens, visually inspected and concluded that there was no problem.
Next slide, please. Also what I want to bring to the attention is this is what is underneath the foam. There are three kinds of ablative material, and we have examples of it up here that you can take a look at. This is light cork, if you want to think of it that way; but part of this is clearly going to be an issue insofar as cryopumping is concerned. We're still looking at that as an issue. Cryopumping, as you remember, is when we have liquid nitrogen or trapped air that liquefies when it is cold; and that's what happens when it's sitting on a ramp. Then when it launches, of course, we have the fuel being transferred inside the external tank and we have trapped gases that eventually need to be what they call flash-evaporated. And that can expand rapidly and break foam, break ablative, and break TPS, thermal protection system bonds. So these kinds of ablative material that you see there from our investigation today to date clearly show that it's questionable on whether it's even needed; and, in fact, the alternatives that are being designed by NASA right now do not include the ablative material underneath the foam. But there will be some changes to this bipod. You can see that a lot of it's at a pretty strong right angle. They're looking at making it more aerodynamic and they're considering where exactly it is, how they're going to pack the connections underneath so they can maintain the integrity of the system.
Next slide, please.
I want to give you an update on RCC. This is, as some of have you seen, a quarter-inch complete RCC that shows you not only the fact that we have a sealant on top but also that we have a silicone carbide coating on top of the carbon-carbon. You go to the carbon-carbon with another silicone coating, and that is a quarter of an inch. That is really what is protecting the RCC.
One of the things that we're looking at, if we can have the next slide, please, is the issue – here's an Atlantis panel where we've had some problems with pin holes and what I will introduce, as some of you have heard before, as oxidation. Oxidation is when you have a void underneath the surface, a void in the surface that translates down to the lower levels. A void or a pocket, if want to think about that, as you can.
Here we have an indication that Atlantis, where they found a defect – next slide – when they went ahead and did further analysis, this is what we call a CAT scan, an X-ray. You can see where not only the surface but also the subsurface shows some problems. Now, this is one way of looking at it, besides the visual inspection. Let me introduce another one. Next slide.
This happens to be what they call thermography. If you hear the term "tomography," that has to do with CAT scans. If you hear the term "thermography," it has to be a flash of heat on the surface and as it cools down, you get an idea of what's underneath it. This is that same panel. It happens to be a repair that went bad, but you can see clearly with Area 3 and 4 that those show some voided areas, as well as Area 5. Now, I introduce this as not the answer on how to do this, but I know NASA is looking at trying to validate this as a probable way of doing nondestructive examination of this very vital piece of the orbiter.
Next slide. I want to also show this one. It's a little bit of a side cut on another panel that was discovered on Discovery. You can see where the carbon silicone carbide is on top and then also that we have the kind of a graze crack and underneath that is a void. If you do a visual or you do a tap test on this, maybe it will penetrate, maybe it won't, but clearly we want to explore the options of improved capabilities for NDE. So that is thermography and also the issue of oxidation.
Next slide. Day 2 debris, I also want to mention, is being analyzed by Patterson Air Force Base.1 We are reading 3R radar signatures on a number of items from tiles, RCC blanket ice, horse collars, and carrier plates to get some comparative signatures that we can maybe get some idea of what it is that floated off on the second day. That's proceeding rapidly.
We also have what I will characterize as an interesting aspect on ascent. On ascent, what you try to do is measure the winds on liftoff. They send a balloon up and they figure where the wind shears are. The wind shears allow you to make a prediction in the software on how the orbiter roll or the power ought to be adjusted to transient through any wind shear. We have an issue with that that we're looking into and I just wanted to share with y'all. The bottom line is, as we move to understand that, at 62 seconds on launch, we saw one of the larger transients we've seen on the solid rocket motor. It was well within parameters but, interestingly enough, the two largest ones we've seen on ascent both happened to be Columbia. Both happened to be going on 39-degree inclinations. Both have lightweight tanks. So we're trying to identify if there is any commonality there as an additional stress load on the left-hand side of the orbiter, because it was on the left solid rocket motor they had this input. Again, well within parameters but just one more as we follow the foam and as we follow the transient stresses on the orbiter that might have been able to contribute to one more issue as we trace down this detective story.
ADM. GEHMAN: Thank you very much. Dr. Widnall.
DR. WIDNALL: Okay. Well, I'm here to report on the activities of Group 3. Our chairman, Jim Hallock, is back at our offices and he's working on the fault tree analysis of vehicle failure that General Barry mentioned. Scott Hubbard and Roger Tetrault are at KSC today. Actually, they'll be there much of the week, basically analyzing debris and kind of postulating what kind of chemical and material analysis would yield important facts about that debris. We expect to be joined later this week, as Admiral Gehman mentioned, by Dr. Douglas Osheroff, who's a Nobel Prize physicist from Stanford University. So we'll work him into the group. So probably I should ask the question what have I been doing. Well, last week, last Monday, I went to KSC to examine the debris and look at some of the damage that occurred in flight. As an aerodynamicist, I'm paying particular attention to the flight profiles, the temperature, dynamic pressures on the vehicle.
I'm really gratified. I've been contacted by so many members of the scientific and engineering community who have provided important data relative to our charge. And let me just give you two examples out of the many inputs that I've received. I guess we have a visual on the first one. It deals with the question of the NEXRAD data system, the weather radar system. You may know that our country is under constant weather radar observation. Do we have a visual of that? We don't have. Okay. Well, Let me show it to you; and it will be on our website. I receive an input from a meteorologist who was a research scientist at the National Center for Atmospheric Research and also spent some time at Lincoln Lab. Basically, the question that the picture raises is: Is there any useful data that could be obtained from the NEXRAD system during the period of time of interest. So I've gone back to this individual and we're working up a sort of search for the data in the national data base and he's going to try to put together a set of sort of snapshots in time of what the NEXRAD system might have picked up. It's a work in progress. I have nothing to report.
Another example. When I went back home on the weekend, I was able to engage in some very profitable brainstorming sessions with colleagues at MIT. Really on a moment's notice. They were very forthcoming. One of the issues we got into was to talk about the thermal environment seen by the vehicle and by its structure and the properties of aluminum at very high temperatures. Without its oxide coating, aluminum is a very reactive material; and when it's exposed to high temperatures and a high-speed gas flow, the possibility exists of vaporization of aluminum, which could be followed then by a very rapid burning of aluminum vapor. That's obviously a scenario that we want to follow up. Our group is examining many scenarios. Some of these scenarios focus on the leading edge of the wing. Reconstruction of the flight conditions from flight data indicates the development of an increased aerodynamic imbalance which appears to be located on the left wing. Some of you may know that NASA has begun a set of wind tunnel tests to determine what kinds of postulated damage on the wing leading edge could explain the level of imbalance. It turns out that a single missing tile or missing panel at the leading edge does not explain the measured effect. So obviously a series of wind tunnel tests will be run to determine what extent of damage is needed to produce the observed imbalance.
Our group has been focusing on the initial damage that was caused by the foam that impacted the shuttle wing near the leading edge. So I have a short video that shows this debris impact. It's about a 4-or-5-second loop, and we'll keep running it. Obviously what you want to look is the piece of foam that comes down, impacting the leading edge. Maybe we should dim the lights so we can really kind of see what's going on. You see the white – there it is. Let me use – I mean, you can see it. Right in there. You see there's – I mean, the video gives you a sense of motion. Obviously the stills that one could get out of this could be a little higher quality. It's very difficult thing, but I think our group is convinced that that foam impacts the shuttle on the lower surface near the leading edge and basically pulverizes, turns to powder. So obviously we're very interested in this.
That's basically all I have.
ADM. GEHMAN: All right. Thank you very much, panel. I'll say something else about that loop there. Kind of an amateur interpretation of that loop there, you only see one piece of debris; but other photography indicates that there's more than one piece of debris. The second gross-level interpretation is that that piece of debris appears to hit – it appears to hit on the leading edge, as Sheila Widnall just said, but on the lower half of the RCC. In other words, the debris doesn't appear to go over the top and under the wing. All the debris appears to go under the wing. So it appears to hit the leading edge but kind of on the underside of the leading edge and then all the debris follows the wind pattern. And it appears to hit the RCC somewhere at RCC Panel 6, 7, or 8, no closer than 6 and no more than 8, which unfortunately is not visible on the on-orbit photograph that we have. It's too close in. As you see, after debris goes by, there's no missing tile. Nothing's missing. So, once again, we have these tantalizing little pieces of evidence that don't fit together. So, with that, I thank the panel and, Laura, we're ready to start.
A SPEAKER: Space.com Space News. You mentioned at the beginning about scenarios that you now have tossed out. Would you elucidate a little bit on which ones you are sure –
ADM. GEHMAN: Illuminate?
A SPEAKER: I was looking for a big word.
ADM. GEHMAN: I don't know that I want to get into the specifics of it, but what we are attempting to do is take these broad scenarios that we have, like hot gas has got into the left wing somehow, and be a little bit more definitive as to what could happen – remember, we can't prove any of this – and if they seem plausible, then what kind of tests do we absolutely need to do either to prove it or disprove it. You know, one of the scenarios might be that this had nothing to do with tiles or RCC, the heat got in there another way. There are some indications that there were some fuselage temperatures that went hot. So one of the scenarios might be that the heat got in there another way. Okay. Without in any way evaluating that scenario, we then say, okay, now what kind of tests, what kind of data would we need in order to bring that one home, just as an example. So what we're attempting to do is to take what has been a very, very broad and open and not-fenced investigation. We're attempting – as I said last week, we're trying to pick up the pace a little bit. We're attempting to focus a little, without leaving anything out.
So I wouldn't want to get into a specific scenario because whichever one I mention will become the favorite of the day, and we don't have a favorite scenario.
MS. BROWN: I would like to ask you to identify yourself by affiliation.
A SPEAKER: Associated Press, I think, for Dr. Widnall. We've heard so much talk about foam, and you mentioned the ablative material. Is there any progress made on just exactly what the debris was that hit the left wing, whether you're leaning towards something besides foam, possibly ice or the ablative material or all three? How is that going?
DR. WIDNALL: I almost want to ask General Barry that question. You know, a lot of what the three groups are doing has a lot of overlap. I think in material and operations, really there is a lot of overlap. We, for example, are monitoring and may run some tests of our own to see what kind of damage is caused by foam impacting, you know, a set of tiles or some RCC. I mean, that would be the way the sort of technology group formulates the problem. The question of what do we see in the video, what do we see in operations, what do we see in materials is almost an issue that's shared between two groups.
GEN. BARRY: If I might comment on that, we've sent in the original photographs and film to a commercial expert. We've got some of our experts at Kirtland who are working this right now and what they are trying to do is figure out through spectral analysis whether that splash you see coming off the wing, if I can use that term, is it foam, is it tile, is it ice, is there any metallic elements in there. It's going to be a very tedious process to go through and they're working very hard in the last week and a half to be able to do that. So we expect to see some results very shortly, but it's an excellent question and that's the process we're going through to do it.
A SPEAKER: Dallas Morning News. Can you tell us whether any of the Panels 6, 7, or 8 that appear to have been hit in that film have been recovered and if there's any telltale condition on them?
ADM. GEHMAN: I'll have to take that question to be specific. In the left wing we have recovered a piece of almost every RCC. Now, it may be a mounting bracket or something like that, but I believe that we're only missing two or three of the total number of RCCs from the left wing. I don't know if anybody wants to help me with that. To get to your specific question, we'll get back to you on that. But we have recovered some part of almost every RCC panel. But so far we have nothing on the left wing. If we had something of the RCC on the left wing which related to this video, we would have told you that immediately. No, we don't have anything exciting about that.
A SPEAKER: Houston Chronicle. My question has to do, I think, for General Barry on the wind shear you saw at 62 seconds. How does this play into what you're looking at that's interesting as though it might be one of these series of events that happened on this particular mission that played into it? And I'm looking for the content.
GEN. BARRY: As we're doing the analysis and trying to figure out what was different about this flight, we're trying to pick on anything and everything that stands out as different. This particular incident had to do with what they call the absolute angle. It has to do with the amount that the solid rocket motor moved to be able to translate either roll or turn the orbiter. This is a software program input that is done on the ground in order to counteract what they know to be a wind shear up top. What's interesting is this one was the highest and the closest to the max dynamic pressure point that they had on flight.
Now, what does that mean to the mishap? We're looking at this as just another additional stress load on the orbiter on ascent. Now, does that mean that they're anything that contributed to the mishap or foam? But this is at 62 seconds. We know the foam that we think came off from the external tank – and we're still clarifying what exactly that material is – came off at 81 seconds. So we're looking for any of these anomalies that might stand out as making this a different aspect. So stress loads and stress factors and what we call high loads also are some of the things that we're looking into on this ascent. We're still digging. It's a detective story, and we take one piece at a time.
A SPEAKER: Can you just clarify, though? You said this is the most extreme or the second most? Did you mean in all shuttle launches or in some other period of time?
GEN. BARRY: All the shuttles go to different inclinations. They have different external tanks, in some cases the lightweight or super-lightweight. It turns out Columbia had two that stand out, and I can go over this in a little bit more detail with you on slides after we break out. But clearly the two that stand out are STS 90 and 107 and both of them were at 39-degree inclinations and both of them had lightweight tanks. Both of them were Columbia. We are just trying to see if there is any kind of a common thread there that might lead us down a path to give us some kind of an insight into the stress on the orbiter.
A SPEAKER: ABC News. I think this is for Dr. Widnall. Earlier there was some discussion about breach in the wing, a plasma breach in the wing. Has there been any analysis done on the debris that gives an indication of where the plasma may have initially – the location where it may have initially breached the wing?
DR. WIDNALL: Well, I think examining the debris down at KSC, I think one sees several interesting things. One sees melted aluminum slag on some of the interior sections in the RCC panel. One sees some very suggestive patterns in some of the tiles and some of the metal around the wheel well. It really is a detective story. I'm not ready to make any final conclusions about it, but the debris is really reflecting the heating and aerodynamic load that it saw. So I think there's a wealth of information in that.
A SPEAKER: But nothing definitive yet?
DR. WIDNALL: Nothing definitive. Again, I don't think we want to leap to conclusions. It's too early on this. There's going to be a chemical analysis and a material properties analysis. Then, of course, the whole question is: How can you analyze that without destroying the piece? So it's the whole question of what sample size can we use to get the data without destroying the piece. So that's a really important question.
A SPEAKER: NBC News. To follow up on that, Dr. Widnall, is what you're seeing giving you any further indication as to whether gas was escaping out or coming in at the left wheel well; and also is the new time line data giving you any further information?
DR. WIDNALL: Well, I'm sure everybody has their favorite scenario on that. The scenarios that are being examined are really a balance, you know between damage to the leading edge, damage to tiles. I guess when I think about everything that's being examined, I would say the bulk of those show hot gas going in upstream of the wheel well and then exiting in the wheel well, but I don't want to be categorical. There may be some other scenarios that are being examined that have other features.
A SPEAKER: The additions to the time line, are they helping you?
ADM. GEHMAN: Everything helps. I've been over the time line kind of line by line myself, and I didn't see anything in there that struck me as being very revealing. A lot of times the more data we get, the more it confuses us rather than helps us. I didn't see anything in the latest revision of the time line, and I'm fully aware of all the issues that are out about the data element that seems to indicate that the stick had been moved. There's another one which we are also puzzling over. It's a few seconds before that. I think it's in the first 5 seconds. It shows a master warning light, which, of course, would have been seen in the cockpit; but the data is not able to attribute what caused the master alarm to go off. So that's interesting, too. It could have been any one of a thousand things by this time because it's at loss of signal.
A SPEAKER: NBC. Back to the time line – and by the way, I've spent a lot of time looking at that and it's a marvelous document for insight and for questions, especially the very first page which talks about the earliest known off-nominal external event, Sequence No. 21 and 21.5, the earliest known off-nominal external event having to do with first a left yaw, then the yaw followed a few seconds later by a right yaw. I don't understand what this earliest known external off-nominal event is. Is it just the RTS firing, or what caused the RTS firing and do we have any idea why at that time?
GEN. HESS: Actually we don't have any real conclusion on that other than as we work through the whole time line, it becomes apparent that the shuttle working with the digital flight controls in auto is compensating up until the very end for the yaw rates that are starting to come on the shuttle.
A SPEAKER: And that's occurring with a QBAR of under 10 PSF? How big of a drag do we have any idea could that be? Is it a 1-or-2-square-foot irregularity, or is it bigger or smaller?
GEN. HESS: I think I might try to pass this off to Dr. Widnall.
DR. WIDNALL: Great. No more stars for you.
GEN. HESS: This is part of the investigative process that's ongoing. They're actually working through the structural scenarios like this so they can have a full understanding about how much of a problem would have to be present to cause the shuttle to react down the path that's laid out in that chronology, and we're just not there yet.
ADM. GEHMAN: Let me jump in there. It's a very good question, and last week I mentioned that one of the things that the time line had demonstrated to us was the impression that things were happening earlier in the reentry than we previously had been given to understand. So what you were looking at there. To me, the question that I take away from that is, even though I understand yours is a very good question, but to me what it gets to is the question of which started first. In other words, did the thermo event cause loss of tiles and thereby these aerodynamic forces or did we lose an aerodynamic surface first which then allowed the heat to start unzippering this aircraft? Every time I think I've got it figured out, I get a piece of data which changes my mind. If the aerodynamic surface were disturbed long before reentry, that then leads you to believe that there was some physical misarrangement on the wing that had nothing to do with entry. On the other hand, all of our photographic evidence indicates that if there was a physical misarrangement on the wing, it was so tiny that it's not visible to anybody else, which would lead you that it was some kind of a thermal event which was the trigger event which then started the unzippering process. So the fact that the orbiter was fighting an aerodynamic misarrangement earlier than we previously had thought makes my riddle very intriguing.
A SPEAKER: Dr. Widnall has avoided answering.
DR. WIDNALL: I'm actually just returning from Cambridge, haven't really had a time to study the time line. You know, it could be one of those situations where the commander leaned on the stick and it would go like that.
A SPEAKER: There was some thermal finds at that point, you know, your water vent temperatures showing an unusual high. Something funny happening there. I'm glad it's got your attention.
A SPEAKER: USA Today. Would you go into greater detail about what the wind tunnel tests have shown?
DR. WIDNALL: Well, it's really quite straightforward; and I got a briefing on this. NASA put a model of the shuttle with a little notch out of the leading edge and measured the aerodynamic moments and then compared those with the basically guidance and control analysis that backed out of the flight data, what aerodynamic forces must have been acting on the vehicle in order to produce the observed flight behavior, the reaction jets and all the things the vehicle was trying to do. So out of that analysis is inferred the aerodynamic forces and moments that must have been acting on the vehicle during the last part of the data where the aerodynamics got really serious. So they tested the shuttle in the wind tunnel with a notch out of the leading edge and they found that the moment coefficients, they had their sine right but the magnitude was about four times smaller than it needed to be. So the obvious thing to do – and they will do this – is to go back into the wind tunnel and remove more sections from the leading edge and see at what point do you get moments that are comparable to the calculated moments from the guidance and control solution.
A SPEAKER: Do you have an idea of how big the notch was?
DR. WIDNALL: I believe it was equivalent to one panel.
ADM. GEHMAN: Yes. That's right.
DR. WIDNALL: So roughly speaking, we would be looking to take four or five panels out of the leading edge, roughly speaking, in order to produce the observed flight characteristics.
A SPEAKER: I'm sorry to go on about this, but it went on a curve. What point on that curve were you looking at, at the maximum at the end or –
DR. WIDNALL: Well, this was basically they have data for the entire flight trajectory up to the point where they had loss of signal. So they can back out the aerodynamic moments and relate them – they know the vehicle attitudes. They can relate it to vehicle attitude and they can calculate basically the moments that existed on the vehicle. So they can back out the effective vehicle trajectory.
A SPEAKER: Florida Today, for the Admiral. You mentioned that the piece of debris we see in the video was not the only piece of debris that you're aware of. Could you tell us what your either photo documentation or other evidence has shown you about other pieces coming off during launch, where they might have come from and whether they hit the vehicle?
ADM. GEHMAN: From other camera angles with a little bit more sunlight, most photo analysts think that there were a total of three pieces of debris. This is the largest one. By the way, they're all clumped together. They all hit the wing at the same time. So you can't tell piece by piece how each one acted, from the photography.
In this particular angle, it looks like one piece of debris; but it's all one event. In other words, they all come off at the same time, they all follow the same path, and then one or more of them hits the underside of the wing. From other angles, you can see what appears to be Debris No. 2 or Debris No. 3; and they all fly the same path. So you can't discern anything out of them. Now, whether or not two of those pieces is foam and one is ice or whether they're all foam with ice in it, we can't tell that right now. I just wanted to make sure that the record didn't seem to indicate we're changing our story about the three pieces of debris. That's still a good valid analysis.
A SPEAKER: Orlando Sentinel, for Dr. Widnall. I wonder if you could talk a little bit about this issue of boundary layer transition. Do we know if Columbia was experiencing that transition at the time of the accident, and how big a factor might this be?
DR. WIDNALL: Well, at the same briefing that we had on basically the aerodynamic effect and the size of the yaw moments and the wind tunnel tests that were done on the single panel missing, roughly speaking, the asymmetric boundary layer transition, more boundary layer transition on one wing than on the other wing, produces a moment that is roughly comparable to one leading-edge panel missing. In other words, it is roughly a factor of 4 smaller than the observed asymmetry in the moments due to whatever damage exists on the wing. So even if you had asymmetric boundary layer transition, it appears to be a factor of 4 too small to explain the size of the moments that existed on the vehicle.
A SPEAKER: So are you saying that has been ruled out as a factor?
DR. WIDNALL: Well, I don't want to rule anything out; but it does not seem to be of the magnitude that was measured in flight.
MS. BROWN: I'm going to take a few questions from the phone bridge; and then if you have a few last questions, maybe you can ask them afterwards. On the phone, do you have any questions? Can you hear me?
A SPEAKER: For Dr. Widnall. Just to clear up a little bit, the wind tunnel combined with what the flight showed. I mean, is there some kind of convergence that you're seeing in terms of you think that the debris hit in this defined area of the RCC and it looks like you maybe have one or more RCCs on the left side of the wing to produce the effects you saw on the mishap? I know you haven't settled on one theory, but is there a convergence that you're seeing in these pieces of the RCC on the left wing?
DR. WIDNALL: Well, I'm not going to settle on a single theory, but I've looked at the after data and I guess from my point of view what I see is a heating event followed by a very rapidly developing aerodynamic event. I think the guidance and control group has done a very good job of backing out those aerodynamic forces. The aerodynamic event, when it occurs, is pretty dramatic. I mulled over that for a while and I looked at the flight profiles and I realized that the aerodynamic event occurs at the time when the dynamic pressure is undergoing a rapid increase of roughly 30 percent. Now, that makes sense to me that the vehicle was kind of coasting along with heat damage and then there was a sudden increase in dynamic pressure that came from the flight and that was the onset of the aerodynamic event. That makes sense. But I'm not going to speculate.
A SPEAKER: Just a follow-up on that. Can you say when in the time line that that aerodynamic happened?
DR. WIDNALL: I'm having trouble hearing you. There is a point in time where the guidance and control analysis indicates the onset of the rapidly increasing – I hate to use the word "yaw moment" because it's so technical, but it's the twisting moment on the vehicle.
ADM. GEHMAN: But you referred to that as a knee in the curve?
DR. WIDNALL: Knee in the curve.
ADM. GEHMAN: In other words, as the vehicle reenters the earth's atmosphere, there's a time where the aero forces start going up more rapidly than a straight line and, lo and behold, at that point the orbiter starts to exhibit non-aerodynamic tendencies. And remarkably more.
MS. BROWN: Can you guys on the phone bridge identify yourself?
A SPEAKER: NBC. I would like to talk to Dr. Widnall if she can hear me. This is NBC. Have you done any analysis or are you having any analysis done on the heating from the videotape to see what was burning on the outside, if it was just nitrogen or oxygen? Have you done any analysis in that area? Also in your theory of the leading edge, I understand that the first four panels were pretty well badly damaged, you only have the supports of those, and then if you have Panels 6, 7, and 8, that's getting to the area possibly of where you have enough to give you this type of aerodynamics that you've been talking about.
DR. WIDNALL: Okay. Well, those are really two separate questions. Let me take the first question. My understanding from the crew video is that what was observed on the video is completely normal, completely expected. It is the normal flashing of plasmas that occurs, what, some five minutes before reentry in the atmosphere. So again, I'm not discounting anything; but I think that is not connected to the later events. Now, I've sort of lost the train of thought on your dynamics question.
A SPEAKER: I was just saying, Doctor, that I understand that the first four RCC panels that you only have small pieces of have a lot of damage of the supports there. Now, if you have those four open on 6, 7, and 8, don't you have enough there to give you the aerodynamic drag that you were anticipating?
DR. WIDNALL: I believe so; but, again, I think one has to go through that scenario very carefully, look at which underlying support structures are severely heat damaged, look at the condition of the individual panels that we do have and really sort that all out. I don't want to leap to conclusions at this point.
ADM. GEHMAN: And we have to compare the left wing to the right wing. It may be that the right wing inboard support structure and RCC may show the same type of heating, in which case the deformations we see in the left wing would be breakup deformations, reentry deformations rather than the accident-caused deformations. But the underlying understanding in your question is correct, that the left wing in general, the pieces of the left wing show more trauma than the pieces of the right wing. But we aren't to the point where we can pinpoint things yet.
MS. BROWN: Do we have someone from the Times Picayune there? Okay. Anybody else?
A SPEAKER: ABC News. This question is for General Barry. Can you explain something to me just so I'm sure I can understand it. Can you explain to me – you said the ET 93, the external tank, was mated, de-mated, and then re-mated, and you said there was a report on damaged foam, it was visually inspected, concluded there was no problem. Can you explain to me what you're talking about there and what time frame this was? What does that mean? Can you clarify?
GEN. BARRY: In the fall time frame, the external tank was mated to solid rocket boosters. It was subsequently decided that those solid rocket boosters needed to be moved to another mission. So what happened was the external tank was de-mated and then re-mated onto Columbia. So this is something that has happened before, as I understand it; but clearly you have to follow the issue on the foam. A problem report was generated, as you mentioned that I stated earlier, which required a follow-on inspection. The concern we've got right now is just to see that problem report, which we've already investigated, and see if there's any more follow-on information that can help us understand cryopumping, maybe some additional cracks that might have been in there. We're trying to look at after or just before last inspections on launch to be able to make that determination. So again as we follow the foam story here, we're trying to look at each one of the iterations; and this is one of those things that stands out as a little bit different that may or may not be contributing to the mishap.
MS. BROWN: Any other questions from the bridge?
A SPEAKER: Aviation Week. I have a question for Dr. Widnall that to some extent relates to the boundary layer issue. I'd like to follow up on a comment made last week by Roger Tetrault. Last week he said Columbia had flown a very hot reentry. My question is: Compared with most other reentries, does the data support that the Columbia was, indeed, flying a somewhat hot reentry, as Tetrault said? If so, does that indicate that Columbia had an early boundary layer transition?
DR. WIDNALL: Well, I have certainly heard that, but I have asked for data on anomalies from some previous flights of Columbia and I'm going to look at that very carefully. As I mentioned, the magnitude of the asymmetric boundary layer, in terms of forces, is not large enough to explain the observed aerodynamic imbalance. On the other hand, it could cause heating problems; and obviously anything that creates a heating problem can't be ignored.
ADM. GEHMAN: We have begun a line of investigation into that. General Barry has some facts over here which I don't think we need to recite; but generally speaking, as far as time of shuttles being in the period of max heat, other kinds of facts like that, Columbia has not endured any more punishment than anybody else. I think what Mr. Tetrault found was that, if you look at various temperature instruments, that there are signs that even though Columbia hasn't been subjected to any more punishment than any other orbiter, he found some places where some of the skin temperatures and things like that were higher than other orbiters. And we haven't made any conclusion, I think.
GEN. BARRY: I might also mention that we have information on the history of the transition for Columbia. The transition time sectors is how they measure it as it makes its entry. The average for Columbia prior to the mishap was 1204 seconds at Point 3, which is about a third of the way down the orbiter, and 1160.6, so two thirds of the way down the orbiter. The average for the fleet – as I said, for Columbia it was 1204. The average for the fleet was 1190. Not much difference. For what they call X/I of 0.6, it was 1160 for Columbia; and for the fleet average it was 1173. Again, not much difference. These are in seconds.
ADM. GEHMAN: These are in seconds in the transition zone, which is how NASA measures it. Now, that's what I referred to as far as time is concerned; and we have to find out whether or not, even though the Columbia spent the same amount of time in transition, whether or not she endured any extra higher temperatures. And that is still going on.
A SPEAKER: For whoever knows about it, can you address the mystery object that was attracted in orbit with the shuttle? Has anybody done an area-over-map calculation, ballistic coefficient, anything like that, and what else can you provide us in terms of information about it? All we heard was 24 hours after launch, it was tracked by radar. Is there a more precise time or date when it reentered?
GEN. BARRY: This is what I alluded to earlier. We've got the radar signature study being done at Wright Patterson right now at the Air Force research laboratory. We've got a number of pieces from the orbiter. Of course, they are new pieces, so we're going to have to do some examination of what might be extrapolated off of damaged pieces. But the intent here is to try to compare those signatures off a number of radars not only from what we have for air traffic control but also from the Air Force radars that came and gave us some information on signatures. So hopefully, with that comparison, we'll be able to maybe put some substance to that second-day orbit piece of material that came by or off the orbiter.
A SPEAKER: General, do you have any more data on the actual orbit of the object... (Remainder of question not heard through speakerphone.)
ADM. GEHMAN: No, we have nothing new that we didn't release last time. The only thing that's new is this reflectivity and luminosity study going on to see if we can figure out what the part was by matching it up with known pieces.
A SPEAKER: For General Barry on the foam damage. Where on the external tank was the damage reported?
GEN. BARRY: The damage on the problem report was at the bipod, so just as we showed up here and also on the screen. So it was on the bipod region of the left side.
MS. BROWN: I think we're going to wrap it up here. Thanks everybody. We'll take a couple of questions for a few minutes up here. I'm going to disconnect the phone.
A SPEAKER: You showed some RCC panels with some voids and some non-conformities in the material. Are you examining whether that is a possible entry without any kind of space or foam restrike on the RCC?
ADM. GEHMAN: Yes and no. It's possible that some of this damage might have led to a loss of an RCC panel, but highly unlikely. What we're really looking at is a complex failure of a complex system. One of the scenarios we're looking at is it's possible that the foam striking a healthy orbiter would not have done enough damage to cause the loss of this orbiter, but it's possible that foam striking an unhealthy orbiter that had problems in it either due to stresses on launch – we talked about the wind shear – too much heating and recoveries of too much heating and transition of years before, ageing of the orbiter, like the RCC faults we see, or a whole number of other complex issues – it's possible that you could do some damage to this orbiter that, if it would have been as a result of a normal event which she could have survived at age 10, maybe she couldn't survive it at age 21.
A SPEAKER: Who makes that RCC panel?
GEN. BARRY: It's Lockheed Martin, and that is where we're going up to see on Tuesday of next week. We're going to the vendor with a team of experts from different areas both in NASA and outside NASA and from academia. We're going up there.
A SPEAKER: What are you looking for?
GEN. BARRY: We're just going to look into, when you do an OMM, better known as a depo in Air Force terms, they will look at the RCC panels, identify any anomalies and, if there are, they will send it back to the vendor. Right? When they do a process flow between flights, same thing; they will identify any problems like pin holes or any abrasions or some kind of corrosion. If that's the case, then they will remove the RCC and send it back to the vendor. We're curious to see what kind of testing is done by the vendor. We're particularly interested in providing some information on possible recommendations on what NDE profiles, nondestructive examinations of engineering could be done in order to improve the process. So I mentioned tomography, which is CT scans. I also mentioned thermography, which is the heat one. So we're looking to see if we can provide some additional insight to the board as well as a possible recommendation on where we would want to go follow on return-to-flight considerations for the RCC.
A SPEAKER: General Barry, have you looked at the communication between space command and the Johnson Space Center as far as the object that came either off the orbiter or flew by? Maybe I misunderstood early on, that that information was not given to NASA early on; or have you looked at the communication between the two groups, how soon did they know?
GEN. BARRY: It was well communicated and well transmitted. So this was something that was very evident early on. It is not usual, by the way, to have this happen. Ice has come off. We've had reports from astronauts of screws and washers, even parts of blankets when the orbiter doors are opened. There are some things that fly out. The question now is, with all the seriousness and obviously with the mishap, was that something that was off the left wing that subsequently was damaged on ascent. So it obviously has a heightened awareness, and it wasn't cited by any of the astronauts or reported by any communications. So we have to go back to the detective story of trying to figure out what it is on radar signature that might help us find out what that is.
A SPEAKER: Is there any thinking in your mind now in looking at all this data of recommendations that may lead to better sensor equipment on the orbiter if we have another tragedy like that? Do you have any feelings early on of what's missing in your investigation now?
ADM. GEHMAN: We're going to issue either preliminary recommendations or preliminary findings as soon as we are content with them. In addition to working hard, many, many hours a day, seven days a week, finding out what went wrong with this thing, we're also working hard on cultural management, budget issues. We're also working hard on return-to-flight issues. So all these things are going on simultaneously. Yes, we have already had a couple of sessions on what could we tell NASA and when. Right now we're not ready to announce it.
A SPEAKER: BBC Newsline. Could I ask you a question on the nature of the debris? Has NASA told you they believe it contained no ice?
ADM. GEHMAN: I'm sorry?
A SPEAKER: On the nature of the debris, whether it's foam, ice, a combination, whatever, has NASA told you that, in their view, the debris contained no ice?
ADM. GEHMAN: Let's see. I don't know that anybody's been that firm about it yet. I think that's still an open question as to whether or not there might be ice in there or not.
GEN. BARRY: This is a concurrent effort that's going on. It's not just a board effort. They're also cooperating with the Air Force research lab to figure out what it is, and also with Kirtland to figure out what it is on spectral analysis. So this is an ongoing effort that we hope to get some results here in the next week or so.
ADM. GEHMAN: I mean, it wasn't a part of your question, but just to give you an example of why this – we just keep working these questions. We never give up on them. We worked for a long time on the issue of whether or not debris passing through the hot exhaust of the shuttle engines would be like putting a piece of metal in a Bunsen burner and you would get a color flash depending on what the debris was. We worked that issue for a long, long time and got a lot of smart people working on it; and the answer is that if it were certain kinds of metal maybe, but everything else, no, you don't get any kind of a flash. So we just never give up on these issues. So I don't want to indicate that we're not getting anywhere on the ice issue. It's just that we keep picking at it.
A SPEAKER: General Barry, I have the impression, is this correct, that you're saying that the existing examinations done between flights on the RCC might not capture flaws that could come back and bite you later in some weird combination or unlucky combination with other factors?
GEN. BARRY: No, I'm not saying that. What we do have is the evidence of what we've asked for questions on what kind of damage has been done to the RCC. There's six that we have where they recorded dings. One was in STS 39 in '91 and 45 in '92, 65 in '94, 89 in '98, 103 in '99, and 102 in '01. All of them are a little bit different. Some affect TCO. Some are due to micro-meteors. Some have to do with impact damage. Some were scraped due to large damage that they indicate. So we're trying to go back to each one of these and find out was and is the inspection of the RCC adequate enough. We know that they do visual inspections – some at 3 feet, some closer than 3 feet, some with magnifying apparatuses to give them a better indication. But what is underneath the sealant? Is there oxidation that has provided some kind of a gap underneath it that we have to be sensitive to? Now, is this something that contributed to the mishap? As the Admiral said, you know, if something hit an orbiter that is not brand-new, that's got – and this is an issue that we clearly have to work in: Ageing spacecraft. Okay. We're entering an era that we've never been in before. In our space exploration, it's always been either we've had our capabilities to use it for one time but now the orbiter is getting to 20 years plus in a lot of cases, certainly in the Columbia's case, and we have to be more suitably attuned to the aspect of ageing spacecraft in an R&D environment. So this is just one of our issues that we will look at as maybe a contributing – non-factor contributing to the mishap but something that we want to make sure we can provide some serious recommendations.
A SPEAKER: Oxidation as in rust? Can you make carbon rust?
GEN. BARRY: No, but you can eat away at it. I guess when you have a pin hole, you can have oxidation occurring inside the carbon-carbon that makes a gap. We've seen evidence, as the photos that I showed you clearly indicate, with Atlantis and Discovery. Some were attributed to faulty repair; but also some were attributed to, after it came back, it was inspected and found to be that way.
ADM. GEHMAN: Think of termites. No, I mean really. Any of you who are boaters, it's blisters in fiber glass. This RCC is built up in layers. The oxidation gets inside and starts opening up gaps from the inside out. So the problem is when you do a visual inspection outside, you never see it.
A SPEAKER: Or tap tests?
ADM. GEHMAN: Just like in a sailboat or any kind of power boat, when you buy a boat, you get a survey; and the surveyor has a little brass hammer and goes up and down the hull, tapping it. This is one of the tests they do here because you can hear a change.
A SPEAKER: National Geographic. At some point you're going to know as much as you're going to know from the finding of debris and so on. Do you anticipate when we're going to quit searching for debris? They're still finding things. I guess at some point when they quit finding things and it's been two weeks and they haven't found anything else – when do you think that's going to happen? I mean, this seems to be you're still finding more and more questions rather than zeroing in on any answers.
ADM. GEHMAN: Well, as you probably are aware, we've just come off a period of actually very bad weather; and the weather is now actually improved in East Texas and Central Texas. Some of the debris that we're really interested in is under snow. So we are hoping that when people get outdoors and farmers start plowing fields and snow melts that more interesting debris further west will start to emerge. So debris is still very important to us. I cannot give you a time. This board is going to work as hard as we can for as long as it takes until we have some figure of merit of certainty on this.
A SPEAKER: You don't have a time frame? I mean, the space station is up there and the clock is ticking on getting the shuttles back in flight.
ADM. GEHMAN: That's right. If we don't know anything, we can't say anything. We can't possibly work any harder than we are. We're already working seven days a week. Like I said before, we have either four or five thousand people every day of the week, out searching for debris. Every one of them covers about 3 acres at a shot. There are divers out there. There are pilots. There are helicopter pilots. You know, the energy level is still very high both among the debris pickers-uppers, the debris analysts and this board and I would not want to put any time frame.
A SPEAKER: You think it would be at least several more months?
ADM. GEHMAN: It will be a lot of weeks.
A SPEAKER: This is for General Barry regarding the problem report on the bipod foam area. Do you know whether that concerned the jack pad closeout or the bipod ramp and what was done and was there a hand patch done or what was the response to that problem report?
GEN. BARRY: No, as soon as you de-mate, you generate a problem report, as I understand it. So that had to be expected after it was re-mated. So after it was re-mated, it was viewed to be okay and they signed off on it. The question we've got, you know, as we move these things around, were there issues of cracks or things that could have contributed to cryopumping. And we're trying to do some experiments. By the way, I might mention also down in Michoud we're going to be doing a lot of experiments with the tanks that we have right now. ET 120 is being looked at this week as a kind of a test case to be able to do some analysis. And we'll do some cryopumping analysis and we'll do some foam analysis to see where the cracks are by trying to figure out through some kind of a dye penetrant, water-based – I think they're still working on trying to decide that – to get some kind of a feedback what is it that could be happening to that particular area on the bipod.
ADM. GEHMAN: I think we'll end it here. We'll stay behind if you want to follow up. It looks like we're getting down to details now that need to be handled on a case-by-case basis.
(End of conference, 2:20 p.m.)
1. Should indicate analyzed by Wright Patterson AFB
Back to Event
|
