Status Report

Transcript: Columbia Accident Investigation Board Press Briefing June 12, 2003 (part 2)

By SpaceRef Editor
June 20, 2003
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ADMIRAL GEHMAN: All right.

General Barry?

MAJOR GENERAL JOHN BARRY: Well, good afternoon. I’m not gonna take anything for granted. Can you hear me now?

By the way, Group One’s been busy working. General Deal and Admiral Turcotte – if you haven’t seen three flag officers trying to learn all the ins and outs of word processing, you haven’t experienced comic relief.

We have a couple of closed fault trees I want to announce for the group. External Tank has been closed, and we have some unresolved questions still in the works, so we still have some more work to do. And we closed out the SRB with the exception of the bolt catcher, and I’ll have a little bit more to report on that here in just a minute.

The other thing I’d like to tell you is that the overall fault trees will be called the Columbia Accident Fault Tree with – we have 17 – out of 234 blocks, we have 17 potentially permanent open items and 2 potentially contributing factors. Be glad to expand on that if you want.

Now, we’ve had some outstanding people burning some midnight oil, literally. I want to recognize Captain Steve Clark (sp), who’s part of our team, who’s been working exceptionally hard.

So, with that brief introduction, let me go into the main portion of what I want to cover. I’ve got two management and two material issues. I’ll get to the slides here in just a minute.

The first management issue is a little bit of what was discussed this morning with our panels on contracts. The Board is looking into, and is still curious about understanding the contractual implications of what NASA’s got. NASA, as you know, relies on financial incentives to motivate its major contractors. Contract fees became a major focus of the program management.

So, the CAIB is trying to finalize its position right now, and we’re considering the following. We haven’t arrived at any conclusions.

This issue about whether it’s an operational vehicle, a high risk development undertaking, we heard Tom Young this morning say it was a one strike and you’re out kind of operation. We’re looking at tying contract fees to performance measures and subjective assessments. It seems to implicate in some cases a distraction from technical expertise.

And we’re looking at possibly recommending a benchmarking by the Navy Nuclear Propulsion System and Aerospace. We don’t want to throw out the baby with the bath water on these issues, so we’re trying to make some very stark distinctions so we can make the merits lie where they may.

The second management issue I want to talk about is integration. Again, we haven’t formed any firm conclusions on this, but we’re examining recommendations on how to break down the stovepipes, or tribes that is used in NASA to, you know, really outline the integration problems on the various shuttle elements and projects.

You may know there’s a Space Shuttle Systems Integration Office at Johnson. However, it doesn’t integrate the entire space transportation system. So the CAIB is finalizing its position on integration, and we’re trying to examine a couple of things on how we might propose recommendations on how to reorganize this integration focus for all the elements of the shuttle, not just the orbiter and not just the other elements, like the SRB, RSRB and the SSME. So the different parts of it.

And we’re trying to look at trying to allow the space shuttle system to look at strategic planning and program development and not just operations. In other words, integrate the whole context of the system.

Now – and a lot of initiatives have been done by the Administrator, of course, as one NASA approach. We want to enhance that with some viable hopefully good recommendations when we get finished on integration for the space shuttle program. And not just do it on paper, and we need better technical integration.

So, with those two management issues, let me look to two material issues. One is the SRB bolt catcher. By the way, this is Group One’s kitchen. This is where we operate.

This one is possible debris. Now, this is one of the things that was brought up to our attention when we were trying to close out the fault tree on the SRB.

I want to make a point. We are not changing our working scenario. However, we need to close this out and we need to make sure that we understand it, if not for STS-107, certainly for any future. So we are listening. It is not just NASA that needs to listen.

So, we’ve done a couple of static tests, and I’ll tell you that the reason this was brought to our attention, at the 122nd – 126th second, there was a radar event that was picked up on SRB separation. We don’t know if it was directly related to the bolt catcher, but I will talk about that in just a second.

This is where it’s located right now. It’s the -.

ADMIRAL GEHMAN: – That’s the tie down. That’s the wrong slide.

MAJOR GENERAL BARRY: Can you skip three slides, please? Not having a good day here. Next one. Next.

Okay, here’s where the bolt catcher’s located and – next slide. This is what it looks like up close. When the SRB separated at that 122nd point, the top part of that bolt goes into the external tank catcher and the bottom goes into the SRB catcher. Next slide.

This is where it separates, right there. We have explosive pressure cartridges that kind of push in, and then it separates right there at the midpoint. Next slide.

This is what it looks like when it is separated. It’s a pretty heavy piece of machinery. Now -.

ADMIRAL GEHMAN: – Why don’t you go back and – can you go back two slides so -. Can you go back one more. You should talk about what returns and what doesn’t return.

MAJOR GENERAL BARRY: Well, this is what returns – next forward please.

ADMIRAL GEHMAN: Forward.

MAJOR GENERAL BARRY: This is what returns with the SRB, so we had recovered the bottom part of the bolt catcher for STS-107. This one we don’t recover because it’s retained with the external tank.

Now, I’m gonna talk about a couple of things here.

The problem we found then, when we were closing out this item was the original certification that was accomplished was done without the real flight hardware in 1979. The other thing we found out is this bolt that was used in STS-107 was done with a new vendor, and the NDE, the Non-Destructive Evaluation, wasn’t done as well as it should have been.

And then we found out, after we were trying to close this out, they did some bolt static tests that resulted in this dome fracturing right there at a lower pressure than was anticipated. In fact, it was below a 1.4 safety margin. So this dome is made of aluminum, and covered with ablative. And if that comes loose, with or without that half of the bolt in it, it still can cause some serious risk to the orbiter.

So this is a possible return to flight issue that we are examining. And again, the issue, as we talked about before, is we want to make sure we have the technical experience and expertise to go through this.

So, that’s one. Can I go to slide number one, please.

This one has to do with the hold down post cable. This is a failure of the orbiter system cabling to hold down the post-pyrotechnics. What that really means is, this flows – there are four bolts on each solid rocket booster that blow just at T+3 on launch, and that’s what allows the orbiter to launch out.

ADMIRAL GEHMAN: We’re talking about the four bolts that hold the entire stack. These are the four bolts on each SRB that mount the SRB to the pad. And then they are, of course, explosively released at T+3.

MAJOR GENERAL BARRY: Exactly right. Now, we got this actually from public input that came in, and we started looking into it. Again, the Columbia Accident Investigation Board is listening. And this also proved to be an integration problem because, when we kept asking questions, we’d find, well, it’s an orbiter issue; no, it’s an SRB issue; no, it’s an orbiter issue; and we went back and forth. So again, it brought home what I’ve already mentioned as one of the management issues that we want to talk about.

Well, during STS-112, there was a failure – and this is 112 now, STS-112 – there was a failure of one of the two signals to initiate the detonation of the hold down post, and only one of the two initiators fired on the eight bolts. You have two systems, both of them are supposed to go at the same time. They both fire at a bolt on each one of the four sections of each one of the solid rocket boosters, and that separates it and allows it to launch.

Our concern was that one of those systems failed to fire and the redundant capability allowed the bolt to blow apart. So they have a redundant capability, but only one worked.

ADMIRAL GEHMAN: It only requires one.

MAJOR GENERAL BARRY: Right.

ADMIRAL GEHMAN: One’s – it’s redundant.

MAJOR GENERAL BARRY: Now, we’re finalizing – the position on this is it’s something like, you know, if we could see what NASA could do on a redesign to make sure that we improve the redundancy. In a nuclear world, we have a lot of cross-straps. So, if one signal goes to one initiator and a bolt, it also goes to the other, so there’s a lot of redundancy elements here.

So, we’re concerned about that. We don’t have this as a direct tie to the mishap for 107; however, it is something that we’re looking at and trying to listen to, and trying to figure out what could possibly be a cause for a next challenge that we have to work.

That concludes my remarks.

ADMIRAL GEHMAN: Thank you very much.

In the case of the bolt catcher fault – the fault tree, that element that included closing out the bolt catcher, as John was careful to say, what we have here is a possibility that we have found another source of debris. We don’t have any evidence that it was a source of debris, except that the radar tracking of the Columbia indicated at the time of SRB separation, 126 seconds, at a time when there’s not supposed to be any debris, it noted a piece of debris. So, we don’t know what that was.

And as we tried to – as we tried – NASA was doing this. As NASA tried to close out the fault tree, we at NASA pushed a little bit on a little additional testing, and we found that the bolt catcher is not as robust as we and they thought it was. So, more to follow.

All right.

MS. LAURA BROWN: Okay. Now, let me just set a couple of ground rules here. We’re – we may go a little bit beyond 2:00 so we can get some questions in here. But each of you has one question, and that doesn’t mean you get to ask multiple questions when it’s your turn.

ADMIRAL GEHMAN: We’ll take the first part of a multiple question.

MS. LAURA BROWN: So, you get to ask one question. So, we’ll start at that end. Matt, do you have a question?

MR. MATTHEW WALD: Matt Wald, New York Times. I’d like to ask the status of your deliberations on specificity, whether you are having trouble deciding, how firm, how specific to be about your conclusions?

ADMIRAL GEHMAN: No, we are not having trouble with that. What we’re doing right now is, we have each of the writers – as you are aware, in this particular investigation, the Board members are the investigators. We’re doing the work. And right now, each section of the report has been assigned to a group or a person, or one of that person’s helpers, and they are now submitting their drafts of each section. And what we’re finding is, is that, when we ask for a three page discussion of a certain thing, we’re getting a 30 page discussion. And so we are now in the process of necking (?) – of getting it down a little bit.

When we get – when we get these inputs whittled down to something that’s gonna go in the report, we will then have some arm wrestling over the specificity and the words that we use. So, we’re probably two weeks away from that stage.

MS. LAURA BROWN: Okay. Bill?

MR. BILL HARWOOD: Bill Harwood, CBS. Painfully restricting myself to one single question.

For Dr. Osheroff, I want to make sure I’m not misunderstanding. You’re saying the cryopumping alone, by itself, doesn’t look like that could lead to foam ejection. Can you expand – (A) is that right, but can you expand a little bit? I’m sorry, but can you expand a little bit on what could cause foam shedding? I’m afraid – I just want to try to understand (inaudible).

DR. OSHEROFF: Well, the assumption is that it’s probably a combination of faults. The easiest one would be to say that you have a separation between either the foam and the coating of the aluminum surface or, in the case of the bipod ramp, maybe between the foam and the super lightweight ablator. And then you have to have, in addition, a hole coming from the surface so that liquid nitrogen could condense in there. And then you need, in addition to that, some source of heat, which doesn’t travel, propagate through the foam direction, but say due to vibrations or something like that.

I must say that most of the alternatives are complicated combinations of several features. I certainly – I think if you look – we’ve seen the left-hand bipod ramp shedding several times, and we’ve never seen it shedding on the right bipod ramp. The big difference between those two is the one on the right is right next to the liquid oxygen line, and feels much less aerovibrations, and that’s probably a good hint as to what it’s about.

MS. LAURA BROWN: Okay. Mike?

MR. MICHAEL CABBAGE: Mike Cabbage with the Orlando Sentinel for General Barry or Admiral Gehman.

Wanted to ask a question about the bolt catcher. You mentioned that there was a new vendor involved with part of that assembly. Have you seen any reason to suspect there was any manufacturing defects or issues there? Bad welds, anything like that?

MAJOR GENERAL BARRY: No, no indications on that. The only thing that wasn’t done properly was the non-destructive evaluation prior to putting that on. So that was our concern. It was more of a procedural element than a manufacturing concern.

MS. LAURA BROWN: Okay. Todd?

MR. TODD HALVORSON: Todd Halvorson of Florida Today for Dr. Ride.

You mentioned a potential recommendation in the previous training of Mission Management Team members, and I’m wondering if you could elaborate on that. What led you to – down that road, and what other potential MMT issues might you all be dealing with?

DR. RIDE: Sure. Our group, as you know, was looking rather broadly into the training of the crew, training of the mission controllers, training of the launch controllers, leading up to 107. And we concluded a pretty comprehensive review of all those training requirements.

We were also the group that was looking into the MMT and the processes that they followed. And through the course of that, we – it occurred to us to ask whether there is training associated with the members of the MMT. The answer to that is, yes, there is. There are simulations that the MMT members go through, but they go through them very rarely. They’re – they have all been held at KFC and they’ve all been related to pre-launch decision-making or launch abort decision-making.

So, I may have the numbers a little bit wrong, but I think there have been three MMT training sessions in about the last four years. So, that gives you a rough idea of the frequency.

NASA does such a good job of training the crew to prepare for a mission, and training the Mission Control team to fly a mission, and training the crew and the controllers to work together to solve any problems, that it seems to us to be an oversight that the Mission Management Team was not being brought into that world of simulation to practice for making the decisions that need to be made during – during a mission.

And that’s – that’s the foundation for the recommendation that we’re – we’re considering right now. We think it would make an awful lot of sense during the integrated simulations, as an example, that NASA does anyway frequently before every flight, to bring in the Mission Management Team to be part of that decision-making during the – during the integrated sim.

MS. LAURA BROWN: Gina?

MS. GINA TREADGOLD: Gina Treadgold, ABC News.

For Admiral Gehman, I guess I’m looking to put the SRB bolts into a little bit better context. I’m looking for a little more detail, sir, before I lead with “It could have been the bolt.”

ADMIRAL HAL GEHMAN: I’m sorry, Gina, you’ll have to ask that question again.

MS. TREADGOLD: Would you put the SRB bolt into a little better context (inaudible)?

ADMIRAL GEHMAN: Yeah. The – as you work your way through the fault trees, of which John indicated the numbers are gargantuan. He mentioned, you know, for example in the one fault tree – the integrated fault tree, there were 235 blocks that have to be closed out. But in things – in some of the other fault trees, there are up over a 1,000 blocks that have to be closed out.

As you work your way through those things, you try and prove that that element did not cause this accident. And in the case of the bolt catcher, and the SRB separation bolts, we now – we have – and since this thing at separation has explosive charges in it and explosively separates the SRBs from the ET, the question is, does it create a debris which might fall back on the wing? Well, it turns out that there are debris catchers called bolt catchers to make sure that no debris gets ejected into the air stream.

So, what we need to do is, we need to prove that that system worked. We don’t need to prove – you see, you’ve got to remember now, we’re the reverse of – you’ve got to prove it’s safe. You don’t have to prove it’s bad. You have to prove it’s safe.

Okay now, in order to prove it’s safe, you have to take and test it. So we did, and we tested the explosive force by which the bolts come off. Then we tested the power that the catcher can absorb, and I don’t know what kind of safety margin you would like to have. If the explosive bolts come off with the power of a 1,000 foot pounds or something like that, then maybe you’d like to have your bolt catcher have maybe one and half times that capability. Well, we found them to be about equal. Is that about – in testing, we found them to be – the margin is about zero.

MAJOR GENERAL BARRY: We had 68,000 inch pounds was expected before it failed, and it actually failed around 56. All right? So the top of that dome actually fractured in the static tests that we did on the ground.

ADMIRAL GEHMAN: Well, that – yeah, so the second part was, after we did this calculation and we found there’s no margin, we actually did some actual static tests. We actually took some domes and pressurized them and, as John says, measured where they failed – measured the pressure at which they failed, a couple of them. In a limited number of tests, found that there is no margin there.

Then we noted where they failed. In other words, where on the dome did they fail, and they essentially all failed in the same place, at the weld. In other words, the welds where the dome is welded onto the flange. And, if it’s a weld, almost all welds are QAed. So, we go back to the QA records. QA records have us scratching our heads.

Do you want to say anything about QA records?

MAJOR GENERAL BARRY: No, it’s just that that’s part of the process. And the engineers were surprised by the failure of the dome on the catcher at the pressure that was given.

So, it brings us back to the issue of what was even brought up this morning, is that, we’ve got to get into a little bit better mode of – we test the solid rocket motors. We test the main engines. We’ve got to start testing the components that are a part of the shuttle and not just the big ones. And this is an example of one, and it’s another one where, you know, we’re trying to listen to see where is the next problem that we need to work on, that we can maybe help NASA.

ADMIRAL GEHMAN: Then, we have something of which we’re scratching our heads about. We’re just at the front end of this and we’re not ready to make any statements whatsoever about whether or not how this affects the process. But, the question then is, we have a potential piece of debris here now.

MAJOR GENERAL BARRY: Or future.

ADMIRAL GEHMAN: Oh yeah, or in a future flight you know. But in this particular case STS-107, it’s potential you’ve got a piece of debris. So then, we go back to the radar records of the launch, and I remember at SRB separation the vehicle’s way down range, but the range tracking radars are still tracking this thing for range safety purposes. And they can see some things, but it’s not like – it’s not like the cameras or something like that.

And lo and behold, at 126 seconds after launch at the time of SRB separation, a – something is scene on the radar, which indicates that there is a piece of debris ejected from the separation. It could be the bolt catcher. We don’t – we can’t prove that.

But now – but in an effort to positively close out the fault tree, you can see – and you multiply this time a 1,000, you can see why this investigation has taken five months. So, here’s one we can’t close out, and we just – you know, we tell you everything we know. So, right now, we’re about 60 percent into this story.

MS. LAURA BROWN: Okay, Tracy?

MS. TRACI WATSON: Traci Watson, USA Today, for General Barry. You mentioned that you either would, or will, recommend benchmarking like as is done in the Navy, and I was wondering if you could go into detail, please?

MAJOR GENERAL BARRY: Yeah, and the other one was at Aerospace Corporation we discussed this morning. What we have is examples of opportunities where we need to encourage any aspect of the federal government, but NASA included, to go out there and benchmark where we think things are working well. And the contracts that are written by the Air Force with Aerospace, as the Admiral talked about and was discussed earlier this morning, as well as what the Navy – Nuclear Navy is doing, can give some insights on, you know, how to develop contracts in a test environment.

Now, how to develop contracts in an environment where you’re launching expendable launch vehicles like the Air Force does. How to develop contracts in a very risky high reliability organization like the Nuclear Navy. So, what lessons can be learned from that? We think there’s potential for NASA to gain some insights.

ADMIRAL GEHMAN: And NASA, by the way, the Administrator had already started a benchmarking program with the – with the Navy Nuclear reactors. That was already ongoing.

MAJOR GENERAL BARRY: That’s right.

MS. LAURA BROWN: Okay, next?

SpaceRef staff editor.