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Preflight Interview: Andy Thomas
The STS-114 Crew Interview with Andy Thomas, mission specialist

You have a job that a lot of kids dream about having. Is being an astronaut what you always wanted to do?

Yeah, pretty much, I think. You know, I grew up in the '60s, and like many people of that age and generation I watched with avid interest the earliest human spaceflights -- Mercury, Gemini, then, of course, the Apollo landings were just absolutely mesmerizing for a young teenager. I think it was at that time that I got this passion of the idea of spaceflight, and I thought, "Wouldn't it be wonderful to be an astronaut?" Of course, it wasn't a very high probability that I'd ever get to achieve it, but with the right kind of education and focus, you can. And I'm living testimony to that.

STS-114 Mission Specialist Andy Thomas, left, and Commander Eileen Collins Image to right: STS-114 Mission Specialist Andy Thomas, left, surveys Space Shuttle tiles with Commander Eileen Collins while visiting the Kennedy Space Center in Florida. Credit: NASA

I've heard you say before that you figure part of the impracticality of it was the fact that you were a young Australian lad.

I think for a young kid growing up in Australia at that time, the prospects of becoming an astronaut were remote, to say the least. But I've always believed that the pathway to many interesting experiences can be opened if you have the right kind of education, and certainly that's true in my case. I think education, in fact, can open doors that you can't even imagine and that would forever remain closed if you did not seek good education. And that's been true in my case.

For example, what was your path in, in education and then your career?

I started with an engineering degree, a mechanical engineering degree in my hometown of Adelaide in South Australia. I followed that with a doctorate, doing some research in some aerodynamics-related problems, and that led to me acquiring certain skills that were fairly unique, and I was offered a position after that to come to the United States and work for one of the large aircraft companies, Lockheed, using those skills. I developed my professional credentials and my professional standing during a number of years with Lockheed. Because my interest was in the space program I eventually left that position and moved to the Jet Propulsion Laboratory, a big NASA center out in California, the center that does most of the robotic exploration of the solar system. I worked there for a number of years in some of their space-based research, and it was from there that I was selected to become an astronaut 12 years ago.

As you look back over those times, do you see a person or persons that were most important in you achieving that goal? An inspiration, if you will?

You know, I'm asked that question a lot and I actually can't point to anyone and say this was a definite role model or some figure that stood out. I know I looked very closely at the people that were being selected to become astronauts. I looked at the kind of credentials they had because I knew that I had to compete on that arena. I also, of course, looked very closely at what the Shuttle program was doing at the time and what kind of expertise that I thought NASA would be looking for for its future astronauts. And that helped. But I can't point to any one person and say this individual inspired me. What I can say is that the individuals who were in the space program in the '60s and '70s, beginning with the first seven astronauts, in fact, were very inspirational people. I was really just absolutely captivated by what I saw them doing on TV and in magazines and so on.

What are your other interests or hobbies? I mean, when you're not busy being an astronaut.

I spend a lot of time, I like to tinker in the garage, build things, build furniture, repair things, do car repairs and things like that. Most recently, I've acquired a small piece of land out in the [Texas] Hill Country with my girlfriend, and we're eventually going to build there. Right now it's just land, and it's really kind of fun to plan out how to use the land and how to maintain its ecology and where we're going to think about putting a house and putting in some ponds and things like that. We're having a lot of fun with that.

You know, Andy, we all assume that, particularly since the loss of Columbia and its crew, that astronauts understand the risks of spaceflight and accept them. Tell me why, for you, you feel the job is worth the risk?

I've always been very interested in the idea of human spaceflight, the idea that we as a species should leave the planet and go out into the solar system, I find just fascinating; it's a very engaging concept. And I see that as a very logical progression in the idea of human exploration, of going out initially in ships from the civilization centers to the uncharted parts of the world, and I see the next step as going beyond the world, of course, out into the solar system. I would like to be part of that, and I'd like to help that process to happen because I think it's an inevitable future that we do have to embrace. And that's what motivates me to fly these missions and pursue this career.

You know, of course, it's one thing to accept that risk for yourself; how does your family deal with the risks of your daily job?

I think they're accepting. I suspect in the case of my parents, for example, they probably don't fully understand what the intricacies of the job are on a day-to-day basis because a lot of people outside the agency don't fully understand what the day-to-day life of an astronaut is. They see just the spaceflight aspect of it, which is probably the highest-risk activity. I suspect people who know me and friends and family will probably look at this upcoming launch with, perhaps a little more trepidation than they have previous launches, but I think that's going to be true for everybody. I think the, the U.S. public will look at this launch that way, too. It's inevitable after an event like Columbia.

It's been more than two years since Columbia and its crew were lost. What was it like for you, as an astronaut, to deal with the fact that an accident had taken the lives of seven of your friends?

STS-114 Mission Specialist Andy Thomas Image to left: Thomas receives help with a training version of his launch and entry suit. Credit: NASA

February 1 two years ago was obviously a very dark day for all of us in the Astronaut Office. I think it was a dark day for the Agency, and a dark day, probably, for the country as well. It is very sobering to lose seven friends and colleagues under any circumstances, but when you see that happen as a consequence of them doing the same thing that you aspire to do, doing the very job that they came here to do, then it's especially tearing at you and it's, it's very hard to accept. I remember that day: most of us were in a state of disbelief shortly after 8 a.m. We were just saying, this can't be happening, no, no, this can't be happening ... we will find something soon, surely they'll come on the radar screen soon or the comm will come up. But of course it didn't. I think that's perhaps an inevitable human reaction in a tragedy like that is the sense of denial, that it's not really happening. And it takes a long time to come to the idea to accept it. I think, initially, you accept the event at a sort of intellectual level, because you see the debris and you see the reports on television and so on, and you have an intellectual understanding of the loss. But, you don't really have a deep, emotional understanding of the loss, perhaps, until later. In my case it was perhaps the next day or the day after that I had to go in to the [STS-]107 crew office as part of my duties. We were securing the office, and I had to retrieve some equipment there. It was very sobering to go in there and see all the desks there with all the personal possessions left there as if they had just got up knowing that they would be back in a few days. Everything was just left waiting for them, and it had that sense of presence that made me appreciate the loss in a much deeper way than perhaps I had up to that point.

When you think about those seven men and women now, what are your best memories of them?

I flew with Mike Anderson on STS-89 the flight that took me up to Mir. And he used to joke a lot about taking me up to Mir and leaving me there. He was an understated person -- you didn't really have an appreciation of his skills because he didn't have a need to advertise them or to have a lot of bravado. It's only when you worked with him, and I flew with him quite a lot in the aircraft that you started to get an appreciation for his background and his talents. He was looking forward very much to subsequent flights after Columbia -- he used to talk about it, he was hoping very much that he could do a flight like we're doing now, a flight to the International Space Station. That was something he, he felt very strongly about and wanted to do, and it was very sad, his loss. I also knew K.C. [Kalpana Chawla] reasonably well. We had mutual friends from her days when she worked at NASA Ames. We used to laugh a lot because, because of our respective backgrounds we were both tea drinkers; hot tea. Of course, hot tea is, it's not something that's drunk very much here in Texas in July or August. So we used to try to make hot tea but the only way you could do it was with a microwave, so I used to joke with her and say, well, if you want hot tea why don't you just go down to the cafeteria and buy some iced tea and put it in the microwave. She didn't see the humor at all; actually, I thought it was pretty funny. Dave Brown was another one. Again, a very understated individual. You wouldn't have an appreciation for the richness of his background and the breadth of the things that he had done until you really engaged him and talked about it. He didn't feel a need to brag about these things, but, you know, he was an excellent pilot. He was a, a doctor, a flight surgeon, a Naval officer, had his own aircraft and had all kinds of interests -- really a, a fascinating individual. There's no doubt about it, a great loss to our program to lose him.

Have you and your crewmates talked about what you're going to do to honor their memory and, and their spirit during your flight?

Yeah, we have. Of course, we modified the STS-114 patch, to incorporate an element of the 107 patch in our design as a tribute to them. We will do something to honor them on orbit. We've kicked a few ideas around but we haven't yet decided exactly what it will be at this stage.

The Columbia Accident Investigation Board pinpointed physical causes for the loss of Columbia and specified some mechanical fixes to make flying the Shuttle safer. I'd like to ask you to assess the improvements that have been made to eliminate debris and detect and repair damage that might be done to the Shuttle.

Yeah, there's been a huge undertaking at Michoud to look at the whole question of how foam is applied to the tank in order to eliminate foam release during ascent. They understand now the very complex mechanisms, the unexpectedly complex mechanisms, which can lead to foam release. They've taken steps to mitigate those mechanisms whereby gases can get entrapped into the foam and then expand and pop the foam off. So that problem has been resolved. The area where the foam was shed for the Columbia accident -- they have removed the foam completely and put in a heater installation instead. That particular piece of foam can't be liberated because it's not there anymore. They've done a lot of work on the ramps and the fittings on the tank to ensure the integrity of the foam. That's given us a very high confidence that large pieces of foam will not be shed during the ascent. It is inevitable that some pieces of foam may come off. That's probably to be expected considering the nature of the technology. In order to deal with that we are going to carry cameras during the launch, which will be looking down at the cavity between the orbiter and the tank to make sure that if any foam is released, we can see where it goes. There will also be ground-based cameras doing the same thing, and airborne cameras doing the same thing. Then when we get on orbit the first order of business, in fact, it's for me, I have to un-strap immediately once the engines shut off, get rid of my helmet and gloves and go to a locker and pull out two cameras. One is a video camera and one is a still camera with a very large lens on it. The Commander will allow the orbiter to pitch up and bring the tank into view within about three minutes or so of engine shutdown, which is much, much quicker than it normally would be -- it normally would be, like, 15 minutes. As a consequence the tank will be a lot closer and that, coupled with the big lenses on the cameras, means we should be able to get some fairly detailed photographs of the tank after its separation. We also have cameras in the well, in the belly of the orbiter, so that when the tank does separate from the orbiter we'll be able to film it and look for any signs of damage. The orbiter itself is fitted with instrumentation inside its leading edge that will detect impacts from any foam; it's an accelerometer-based system. So if you put all those together I think you could say there's, with a lot of confidence, that we shouldn't have foam damage on this flight, and where we'd have foam damage we would understand where it is and the severity of the damage in that very unlikely scenario.

You know, there are thousands of people all across the country who have been working for more than two years on all the things that you just detailed in order to make the Shuttle fly safer. Tell me what you think about the contributions that have been made by all of those people.

A lot of people have worked very hard on this effort. It's actually quite impressive, I think, to realize what has been done in the two years since the accident with all the corrections to the tank, all the detection systems, the camera systems, and of course the large boom we're carrying that'll do the inspections. As a government agency we don't have some of the freedoms that private enterprise has. We have to conform to certain bureaucratic requirements in all the engineering we do, and that carries an overhead with it. So all of that development that's been done in the last two years has had to go through a lot of checks and balances that were required, really by Congressional mandate. That's been a very big administrative undertaking as well as a big engineering undertaking. People from all over the country have been involved in that engineering and administrative work, I think because people recognize that it is important for this country to get back into the business of human spaceflight, that we don't want to be stuck on the ground and we don't want to be a non-spacefaring nation.

What has it meant to you when you've had the opportunity to go to the many NASA centers and meet and talk with the people who've been also part of the Return to Flight team?

Actually, it's a little humbling in a way, because you go to the NASA centers and some of the contracting companies and so on, and the people there are so effusive and enthusiastic about meeting the crew of the next mission. These are people who have spent years working these various problems. They've given their life and careers. They've made huge contributions and they've given so much, and yet they're the ones that are enthusiastic about meeting us. We get to ride the vehicle, we get to have the flight, but these people have done all the work so they're the ones that you really have to take your hat off to and say, "Hey, thanks for a job well done."

The repair procedures for the orbiter that have come about as a result of CAIB recommendations are still being fine-tuned. Some of them are still in development. And yet the Shuttle program's confident in moving ahead with this flight even though there are still procedures being tested and certified. And you're comfortable with that?

Oh, yeah. In fact, because of the detection systems, the photographic systems, the boom inspection systems, and what has been done to the tank, I have a lot of confidence about the safety of this flight from the point of view of foam liberation and damage to the Thermal Protection System. I don't think these are going to be issues for our flight at all. So, I'm comfortable to do the flight even without developed and refined TPS repair techniques. I think one of the things that's come out of this is that repair of the Thermal Protection System is that a system which has to allow itself to be heated to incandescent temperatures for prolonged periods of time and be subject to aerodynamic loads for periods of time, is a very difficult problem. It's a very big engineering challenge, to be able to go and do that not in ideal laboratory engineering conditions but in the vacuum of space and in an operational vehicle orbiting the Earth. That's a tough, tough problem. I think we have realized, and the people working it have realized, just how tough it actually is. But not only that, I think they've also realized how sensitive these vehicles are to damage to the Thermal Protection System. I think perhaps people had underestimated how important even small cracks and delaminations and things like that can actually be.

STS-114 Mission Specialists, from left, Steve Robinson, Charlie Camarda, Andy Thomas and Soichi Noguchi Image to right: Four STS-114 mission specialists share a moment of weightlessness aboard NASA's KC-135 aircraft while training for their mission. They are, from left, Steve Robinson, Charlie Camarda, Andy Thomas and Soichi Noguchi. Credit: NASA

Beyond the physical causes of what took Columbia, CAIB cited organizational and human factors within NASA that bear responsibility as well -- the management system and the safety culture here. Do you see a change for the better in those areas in the last two years?

You know, the cultural question is an interesting one because I think it was a very important issue in the Columbia accident. I was a little sorry, for example, that the CAIB Report did not actually tie a specific recommendation to that issue. They did talk about the issue and recognize it, but there was not a specific Return to Flight recommendation on that issue, probably because it would be very hard to have a tangible recommendation to address that issue. That's something that could be watched and for which you could build metrics. I've worked in a number of organizations professionally since I graduated from university, both private industry and a government lab. I would have to say in all of those organizations I've seen cultural problems, especially in private industry. Even in my university days I saw cultural problems. I think many organizations suffer from cultural problems. The difference that exists here now at NASA as a consequence of the accident is that people now talk about that topic openly and recognize that cultural issues are important to the successful undertaking of these great endeavors that we're trying. That was not fully appreciated, so now the whole question of culture is raised in everybody's mind. Given that, a lot of people say, well, has the culture changed, and you have to understand that for a culture to change it's going to take years. The culture is the people, and the policies of the managers, and it's not going to change until a new generation of people has grown into the positions and the organization has evolved. That's the natural way it should be. It would be quite unrealistic for someone to say in two years, "Oh, the culture is completely changed, everything's different." It just doesn't happen that way when you have a large organization of people. It's going to take time. I do recognize that here, in this agency, the people are very keenly aware of the need to do that, and that's what makes NASA right now different from all of those other organizations that I've worked for in the past. But, we need time.

STS-114 is called LF-1. What does LF-1 mean? What are the goals of this flight?

Logistic flight is what LF stands for. Since the Columbia accident there has not been a Shuttle to the Space Station in over two years, and the Space Station really needs the Shuttle. The Shuttle, in fact, needs the Space Station. The Shuttle was a vehicle designed to shuttle to and from low Earth orbit, and you need somewhere to go there, and the Space Station is that. That's the, the mission of the vehicle. But as a consequence of the Shuttle not flying, there's a lot of accumulated trash and equipment on the Station which needs to be brought back. There is no downmass capability to speak of with the Progress vehicles, there's also a lot of resupply necessary because the upmass capability of the Progress resupply vehicles that we've been relying on is very limited. So we're carrying some experiments, we're carrying clothing, we're carrying food, water, and equipment for the Station in the MPLM in the payload bay of the orbiter. We will offload those while we're docked to the Station, and then reload all the accumulated equipment and trash and detritus and whatever that needs to come back, as you might expect, from a vehicle that's been operating untended from a Shuttle for two years.

As you noted, the capacities of the Russian launch vehicles that have kept the Station supplied are, are limited in comparison to the Space Shuttle. Does that make the Return to Flight of Space Shuttles critical to the future of ISS?

Oh, yeah, I think so. I don't know how we could run the Space Station as we have it without the Shuttle. It would be very difficult. You know, I flew on the Mir space station, the precursor to the International Space Station; that was a remarkable vehicle that had been built without a Shuttle. And you could see the consequences of that. For example, large pieces of equipment that were no longer needed were still there, they were just floating around tied off somewhere; there was nowhere to put them. You couldn't send them in the Progress because they were too big. In fact, the Mir space station was extremely cluttered as a consequence of that. We don't want that to happen to the International Space Station. It needs the Shuttle for these missions. The Space Station right now has four Control Moment Gyros. One has failed, one is suspect, and I'm sure they're biting their fingernails over the other two. One of the things we will do on our mission is repair one of those gyros. That's a very important function, because that's what stabilizes the Space Station and helps it maintain attitude. We need to do that because if the Space Station were to lose attitude control permanently then it would be essentially the end of the vehicle because we wouldn't be able to dock with it, we wouldn't be able to service it, and we wouldn't be able to control it.

In the first hours of your flight you're going to be confirming some aspects of the redesign of the external tank, as you referred to a few moments ago. What's involved in getting the data from the sensors in the wing leading edges and from the cameras inside and outside the vehicle back down to the ground?

Firstly, the cameras. With the modern technology of digital cameras it's fairly straightforward. You have a memory card, we'll put it into one of the computers, we'll set up the computer network, which the ground can remotely access, and then during the night they will actually retrieve those images and downlink them through the communications system. It's pretty nice. The wing leading edge sensors are small sensors that are imbedded in the leading edge throughout the vehicle. All those data come into the crew compartment through a telemetry system into a laptop as a, huge files of numbers and we have to set up the computers to receive them. Once we've done that then the ground can also, during Flight Night 1, access those and bring those down to the ground while we're sleeping.

On this mission you're going to also be the first crew to perform a new task for Shuttle crews, inspecting the exterior of the orbiter for possible damage. First, describe this new Orbiter Boom Sensor System and how it's designed to learn whether or not the Shuttle has been damaged.

This of course is a consequence of one of the recommendations of the CAIB Report, the accident report, the ability to inspect the orbiter. A boom has been developed -- it's based on the robotic arm. It's very similar to the robotic arm. Whereas the robotic arm lies in on the port side of the orbiter, this boom will be on the starboard sill in a complementary position. It contains at one end a suite of sensor systems, laser-based sensor systems, which can image a surface and can actually measure imperfections, three-dimensional imperfections, in the surface. The other end of the boom has a grapple fixture on it which enables us to grapple it with the robotic arm and communicate with it electrically through that grapple fixture. That's going to be the basis for doing the inspections on Flight Day 2. Flight Day 2 is a very busy day for us because we are going to inspect the orbiter to make sure that there has been no damage during the launch phase. We will unberth the robotic arm, swing it over to the starboard side, grapple to the boom, lift the boom up out of the payload bay, do some calibration checks of the sensors on the boom, then we'll start systematically sweeping it back and forth across the starboard wing leading edge; I think there are about three passes. Then we'll bring it up around the forebody of the orbiter, the nose cap, and we'll do a series of surveys around there, all the time recording imagery data and downlinking it to the ground. After we've done the nose cap we then swing it around and do the port wing, time permitting, and we'll sweep it back and forth across the port wing at various angles to make sure that the integrity of the RCC [Reinforced Carbon-Carbon] is good on the port wing. It's a pretty ambitious undertaking because it's never been done before. We have a lot of arm sequences that we go through to do it. We've been practicing it and I think it's going to work out well. It is a big time hit to the flight, though, because it takes a full day to complete.

A full day to look over the exterior; it's, well, some would say it could be a fairly tedious task to spend an entire day making those small movements. What's the plan to make sure that you've got somebody who's still sharp in charge as this goes on?

You've hit the nail on the head, because when you're doing something like this which is somewhat repetitive it's easy to let your guard down. When you let your guard down, something could go wrong. That's a risk. We've set up a crew coordination. We will have four people actually engaged in this task; three really, but a fourth one there. We've split up the tasks of operating the arm, recording the data, and monitoring the clearances of the arm. That's the big issue. When you swing the arm 'round with this huge boom on it, you don't want it to run into something -- you end up creating the kind of damage you're trying to look for. So we've set up the management of our crew tasking on those three areas. We also have a fourth person who stands by to substitute for any one person if they need to take a meal break or something. That fourth person also can provide out-the-window views on those occasions when the arm is in view out one of the windows. We think with that strategy that we've got enough eyes watching this activity that we can perform it properly.

Inspections are going to resume during the final phase of docking to the Station as well. Talk about the plan to inspect the orbiter's upper surfaces and then to spin it around so that the ISS and its cameras can have a look.

STS-114 Mission Specialist Andy Thomas Image to left: Thomas takes a close look at a Space Shuttle tile. Credit: NASA

As we do the rendezvous on Flight Day 3 and we come up below the Space Station on what's called the R-bar, the radial direction, we are going to pause in the approach at that point at I think 600 feet, and the orbiter will do a complete 360-degree pirouette, basically. The crew on board the Space Station, while we're doing that, will have cameras with some large lenses and they will actually image the entire lower surface of the orbiter to look for damage and in fact, the upper surface as well, for that matter. These will be on digital images, which also will be downlinked from the Space Station. If some sites are seen where it's thought there might be some damage based on that imagery, on Flight Day 4, I believe, we will actually unstow the boom and do some additional targeted inspections, we're calling them. The idea is that this gives us the capability that the people on the ground have identified sites that they're concerned about and we have time set aside that we can go and look at those sites with the inspection boom and make sure that they are in fact in good order. I should point out that what we're doing on the flight to check the integrity of the orbiter is really only a small part of this. There are a lot of people on the ground who are receiving all of these data that have been generated from the on-board cameras, the airborne cameras, the launch cameras, the Station cameras for the pitch maneuver and the wing leading edge sensors, and then all the boom inspections. There's a huge wealth of data coming down, and we have a lot of people who are set to receive the, all of those data and look at it and compare it to preflight information to check the integrity of the orbiter. So we, we're not alone in this by any means; we have a lot of really smart people helping us out.

Once the docking is complete, have you given any thought to what it's going to be like to be there when Shuttle crews finally return to the International Space Station?

Well, it's going to be interesting. From my own perspective it's actually going to be interesting because I was at the Space Station four years ago -- it'll be four years -- on STS-102 in 2001. One of the things that struck me when I went on the Space Station, especially the Russian segment, was, it was a sense of deja vu -- it was like being on Mir again because the Russian segment is very much like Mir. It even smelt like Mir. The air treatment systems are the same and they leave that slight residual odor. Sergei Krikalev, one of the senior Russian cosmonauts, says it's "the space smell." You get used to it. But I was really struck by this deja vu sense I had when I went into the Russian segment of the Space Station. It's going to be really interesting for me to go back again now, four years later, and see how I react to that. The other thing that's going to be interesting for me personally is there's a lot more Space Station now than there was when I was there four years ago. Even though we haven't had a Shuttle in two years, there was two years of assembly that took place after my last flight. So there are some much bigger truss segments on board now, and there's a new airlock on board, and I suspect there's probably a lot more accumulated equipment on board, too, which we're going to help them do something about.

Let's talk about that. The next day after docking is the day that you install the Multi-Purpose Logistics Module. Talk about what is involved in that procedure.

That procedure will be executed by Wendy Lawrence and Jim Kelly. At that point, of course, we're docked to the Station so we'll be able to use the Station arm. We will have moved the boom that we're carrying out of the way, and they will bring the Station arm down into the payload bay. They will grapple the MPLM. Myself and probably Charlie Camarda will be on the flight deck and we will release the latches that restrain the MPLM in the payload bay. Once we've done that then Wendy and Jim can lift the MPLM up out of the payload bay and mate it to the side of the Station. They're going to do pressure checks to make sure that there's a good seal between them, and if there is they can open the hatch and we can start the transfer operations, which is going to be a big part of the flight for Wendy Lawrence and Charlie Camarda, especially.

Another part, a big part, of the training that you all have been through the past couple of years has focused on spacewalking techniques for making repairs to the Shuttle. How involved have you all been in the development of the actual technique?

There's been a lot of work done, especially in the last year, on looking at ways of doing repair of tile on orbit. Tile is a fairly fragile material. It's a very unusual material; it's a silicate glass and to repair it, even on the ground, is not an easy thing. But to do it in orbit, in a spacesuit, by the way, is much more difficult. We've been supporting the developers on that effort with flights on the KC-135, where you do it in zero gravity to look at the right kind of tools and the right procedures to use. A critical question in all of that is, how does the material behave -- the material they're going to use for repair for the tiles is a kind of a two-mix, like an epoxy like you might have in your garage that you mix two components together, squirt it into, say, a gouge or a hole on a, if you had one on tile, and then smooth it out a bit and let it cure. It sounds easy, but in space it's very hard to do. There are a lot of questions about how the material will flow in space, where there's no gravity; there's also a vacuum so there's a lot of questions about how the material might outgas in a vacuum. The only way to really satisfy yourself that it's going to behave the way you need it to behave to be a viable repair, is to actually evaluate it in space.

And that's what the first spacewalk is, in this mission is all about?

That is correct. We're carrying a box in the aft of the payload bay and the box has a hinged lid. The crew will open it in the first EVA. Within that box there are a number of samples of tile and Reinforced Carbon-Carbon that have been intentionally damaged, and the crew will be applying material to these samples and patting it in using different strategies, and the material will be allowed to cure and will be brought back and tested in test facilities here on the ground to see just how good the repair technique actually is.

And you are the choreographer for these events.

That's correct. I have the role as IV for that EVA and the other two. I liken it to being the conductor of an orchestra, and it's an orchestra of two players, but nonetheless you get to basically orchestrate the operations. EVAs are very structured, organized activities; they have to be for safety and to understand what's going on. The crew spends an awful lot of time practicing the sequence of events from the moment the EVA starts and they go out the hatch to the moment it ends and they close the same hatch. It's all very structured and it's all very timelined, and we spend a lot of time working on that. And I will be basically leading the two EVA crewpersons through that timeline in each of the EVAs.

The second EVA calls for the replacement of one of the Control Moment Gyroscopes that you referred to a few moments ago. That one's got a fairly well laid out set of steps, if you will.

Yes, it has. That's an EVA that was on the original flight well before the Columbia accident, so it's a very mature, developed EVA. We understand the process and the procedures involved to do it. The Control Moment Gyro is very important to the Space Station. There are four of them. I liken it to those little toys that you used to have as a kid where you'd have a gyroscope and you'd put it on your finger, spinning, and it would just balance there. And it's exactly that principle that these devices use to hold the attitude of the Space Station as it orbits the Earth. They're really important for that, they use electricity generated from the solar panels to do it; that means you don't have to use propellant which is a very important resource on a spacecraft. You don't have to waste it just holding attitude; you can save it for the important maneuvers. If these Control Moment Gyros fail, you no longer have control of the spacecraft, the attitude of the spacecraft. Actually, in an extreme situation if you lost control completely you'd never get the spacecraft back; you'd lose the spacecraft. It would be catastrophic failure, so these are very important devices for the, to maintain the stable flight of the Space Station and to allow vehicles to dock with the Space Station. They do fail from time to time and there's one that has failed. It's really important that we get it replaced. Not only that, it's important that we bring the old one back because the specialists on the ground need to understand the failure mechanisms of these devices so that future designs can have that failure mechanism built out of them, designed out of them.

STS-114 Mission Specialists Charlie Camarda, left, and Andy Thomas Image to right: Andy Thomas, right, consults with fellow Mission Specialist Charlie Camarda. Credit: NASA

There is a third EVA, and that's centered around installation of what's called the External Stowage Platform. Tell me what that is.

It's a large platform just as it sounds: it's probably 8 feet by 6 feet, and on that platform are spare components of the Space Station -- some camera stands, some pump units, and various electronics boxes. Rather than carry these components to the Space Station piecemeal, you can just carry the platform and put it on the Space Station and then you've got a place where you can have all your spares where you can put all the failed components in the times that you need to replace components. So on the third EVA we're going to take that platform, which is being carried in the payload bay of the orbiter; the crew will release it in EVA, the arm will grasp it, lift it up out of the payload bay and the crew will help the arm to mate it to the side of the airlock on the Space Station, where it will be permanently fixed, so that these spare components are available for future repairs of the Space Station.

A couple of other tasks on that EVA, too, right?

There are a number of get-ahead tasks. We will probably, in that EVA, be checking the tile repair that was done on the first EVA, because the samples will have been outside curing, hopefully, for two days, and the crew will probably open the, the box and allow cameras to do an inspection of the repair. They will also actually probably check the hardness of the repair with some tools to make sure that the repairs worked successfully.

The day after the third spacewalk you close up the MPLM; the day after that you undock, you come home. But it's the last big event on this flight, the landing, that's going to get more attention than, well, maybe any other Shuttle landing. What are your thoughts about that part of the flight?

Yeah, I don't think it will be the landing, I think it will be the entry that will get the attention. It's going to be interesting. You know, after the Challenger accident people tended to have this sort of, breathe a sign of relief after SRB separation, almost with a sense of false complacency like the SRBs are gone, now they just ride the main engines, everything's fine. I think that was probably a false sense of complacency, actually. Spaceflight is an inherently risky process, and we now know how risky it really is. I think people shouldn't have any false sense of complacency -- the mission is not safely over until wheel stop. I think people now will be watching the entry with a, perhaps a, a heightened sense of awareness, a little more tension, a little more concern just to make sure that it goes all right, because it's the first entry we'll have done in 2-1/2 years. From my perspective what I'm looking forward to is that I get to ride on the flight deck during entry. I've had three flights on the Shuttle but all three of those entries were down on the middeck, so I've never actually seen an entry from the flight deck. I'm told it's a pretty spectacular light show, so I'm looking forward to seeing what an entry looks like from the vantage of the flight deck. I think it's going to be pretty interesting.

I've heard it said that STS-114 opens up a new chapter in space exploration, one that's going to transform a Vision for Space Exploration into a reality. Do you agree?

I'm not sure I'd put it in such embellished terms, but essentially it's true. When, when we lost Columbia, I think, I think we faced a decision point. That was, do we continue in human spaceflight, or do we pack up and go home. I think the nation, basically, probably thought about that, and I think the nation decided that we're going to continue human spaceflight. I think that's something that, by and large, the American people want to see this country involved in. So, this flight, 114, is symbolic in many reasons. It's not just that it is the technical accomplishment of returning the vehicle to flight, it's the symbolic accomplishment of saying we are back in the spacefaring, the space launch business, and we are going to resume flying into space. We're flying in space, but we haven't been flying into space, and that's why this flight is important. I think it's important to the country to see that and to recognize that. We are all employees of the people of this country; their taxes pay our salaries. So we have an obligation to them, and we have to show them that their trust in us is valued and is earned and is worthwhile. And we can do that by showing them that we can bring this vehicle back into space and bring this country back into the business of human spaceflight. So that's one thing that's very important about this flight. The other thing does connect us to the Vision and where we're going. I think the accident made people think about, well, if we're going to do human spaceflight why are we going to do it? What's the payoff? What's the reason for doing this? And, the emphasis in the '80s, for example, was largely on a space station; well, we've got that. And, we need to have a reason to do this. It's fun and exciting to do, but that's not enough reason to do it. You've got to have a really viable, tangible reason. And, to me, that reason is exploration, and going beyond the Space Station, and returning to the moon and returning to Mars. And, in a sense, this flight is a symbolic step in that direction. It is kind of a new paradigm for us as an Agency and the directions we're going. I think this flight does somehow capture that symbolically, that step that we've, that new step, that new direction that we're taking.

Well, let me get you to, close the circle then. In your mind, how does flying this mission to go on to get back to the Space Station, how does the International Space Station help us achieve that Vision and, and pave our, our path to the future?

That's actually a good question, because a lot of people don't understand that the Space Station and what we're doing with it is really going to help us go beyond low Earth orbit. And it's a connection that a lot of people don't appreciate. If you're going to go beyond low Earth orbit to the moon or a six-month journey to Mars, you have to have systems in your spacecraft that you know will run continuously for long periods of time, you're going to have the right life support systems, you've got to have the right electrical systems and propulsion systems. Everything has to work properly because when you do a mission to Mars there's no going back -- if something's wrong, you can't just get down to Earth and fix it. The Space Station is going to teach us how to do that. It's teaching us what kind of technologies you need to operate and maintain a spacecraft in the hostile environment of space for long periods of time as you would have to do if you were doing a deep space interplanetary mission. That's one thing. There's the human element, too: Space Station's teaching us what is required of us as humans to live and function in space. It's teaching us what is the consequence of living in space on us as human beings, and it's teaching us how to mitigate some of them, the deleterious effects, of spaceflight. We need to have answers to all of those questions if we're going to go on beyond low Earth orbit to the moon or to Mars. And that's where the Space Station can really help. So I see it as enabling all the technologies and capabilities that we're going to need to do deep space exploration.

+ Read Thomas' 2004 interview.