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Preflight Interview: Carl Walz

The International Space Station Expedition Four Crew Interviews with Flight Engineer Carl Walz.

Our Crew Interviews with Carl Walz, Flight Engineer 1 on the fourth expeditionary crew to the International Space Station. Carl, as you prepare to take off on a five-month-long spaceflight, tell me how you see the mission-what are you and your crewmates being sent to orbit to accomplish?

A: Well we're going to go and fly for a really long time, and then on the plan we have some science activities that we'll be doing, kicking those off pretty much right away-logistics activities where we're going to stow the items that come up during the UF-1 flight, during the Progress that'll arrive, and then we have checkout activities that we'll be doing with the new software that we'll get prior to the 8A flight, so we'll be checking out a complete new set of command and control software…be the test engineers, if you will, for that. Also test engineers for how that affects the robotic arm, and then construction engineers as we install the S0 truss that comes up on the 8A flight. And then finishing that up we have the UF-2 flight that will arrive and we'll assist in the installation of the Mobile Base System…that'll attach to the Mobile Transporter. So we have a lot of activities-science, engineering, tests-and oh, it'll keep us pretty busy, I think, during the five months.

How do you see yourself on this mission-are you a scientist, or a space explorer, or something else entirely?

Well I see myself somewhere between a test engineer and a maintenance man, I guess. We'll spend a lot of time testing out systems making sure that they're working right; we'll be using those systems during the flight, and then the other thing that I failed to mention previously is that we're going to be maintaining systems on board the station, upgrading, we're going to install new solid-state memory units in all the command and control MDMs, and we'll be reconditioning the TVIS, the treadmill that we use for exercise, we'll be replacing six of the electrical outlets on the space station, so we just, we have a lot of different items that we'll be doing on board.

That's a range of different kinds of work that you've got to do…different qualifications that you and your crewmates have to have to pull it off. How did you get to be a person that had that sort of background? What did you do to become a guy who was "astronaut material"?

Well, you know…I think I started off when I was very young watching the Mercury and the Gemini flights, and, of course, the Apollo flights and you know, people, I grew up in Ohio, so John Glenn, Neil Armstrong, you know, were big heroes for me because not only were they astronauts they were Ohioans. And then I got involved in the Air Force and in the flight test business where a lot of our flight test engineers-El Onizuka, Jerry Ross-came out of the Air Force from the flight test engineering field. And so, I sort of have tried to follow in their footsteps. And then through the missions I've developed, in my previous missions developed a lot of skills, and then through five, almost five years of training for this flight, of course, developed a whole new set of skills ranging from language to operating, you know, Russian Soyuz spacecraft.

Your Air Force career began after you graduated from college, right? You were not an ROTC student or…

I was.

…or you were? Tell me about it.

I was an ROTC student but then after I was commissioned after the end of my, when I got my bachelor's degree, I took a two-year delay and got my master's degree and then came on active duty. So there's a little bit of time when I was inactive reserve and then I've been on active duty ever since, since 1979.

You touched on this a moment ago; I'll ask you expand. You talked about John Glenn and Neil Armstrong being heroes. Why did you want to be an astronaut?

Well, I think the astronaut business is sort of a…it combines engineering, it combines science, and it combines operations in this new and exciting frontier of space. And, so back when I was in college, you know, I was thinking about that and that sort of drove me into a science major and it also drove me into the Air Force, and then looking out at the Air Force and who was being selected for space shuttle crews sort of led me into the test engineering. So it's a, sort of been an iterative process, but it's worked out.

Are you, for you, then, it's something that really got started for you when you were in college?

Well, I think college was an enabler; you know, it's given me the background necessary to be selected. But I think I really found the path once I was in the Air Force and started looking around and meeting people who had come to JSC for selection interviews, and trying to follow in their footsteps.

Are some of those the people that you look and, at your own past and say that they're the significant influences on your life?

Yes. Well, I think that, you know, certainly those people were tremendous influences…that sort of pointed me in the right direction but, you know, if you go back even farther again to people that really made a difference, of course…my parents, who really helped enable me to do well in school, provided the opportunities, the good, stable home life; my high school teachers, you know, especially my physics teacher, Mr. Eich, who made science really interesting and, you know, sparked my curiosity; my physics professors in college, of course, you know, were very supportive and helped; and, then of course my family, too, has, my wife [and] my kids have been big supporters here, keeping me going, especially this last five years that have been, you know, a tremendous challenge for us.

Let's talk about that. You and Dan Bursch each have three previous flights to your credit, which gives you a combined experience of about two months in space, but now you're looking at a flight that's going to keep you in orbit for five months. What are the big differences in the way you've gone about preparing yourself for such a different kind of mission?

Well, of course, you know, the training has…sort of, the amount of training has tripled, maybe quadrupled as we've not only had to worry about the traditional things that we've done on our previous missions plus add on the Russian segment station, the Soyuz, and then all the other Russian EVA stuff, and that adds on to our U.S. EVA activities that we've been learning about, and the SSRMS and Canada. So it's been a tremendous volume of work, and, you know, we've tried to really compartmentalize but we've had a lot of time also. So, we've been training for a long time and trying to keep track of all these systems. I think the other thing that we've prepared for, we spent more time thinking about how best to psychologically prepare not only for ourselves but for our families. One thing that's helped us is that we've traveled so much during this training whereas in the past we haven't done a lot of traveling during our training flow, and so it's two weeks of a typical spaceflight seems like a lot, you know, we're usually gone five, six, up to eight weeks at a time for training in Russia, and so it's like a mini-flight. And so we've kind of been doing this all along. And so now we just have to take a little bit more care because we know it's going to be a little bit longer.

On the question of how long you've been at this, I don't know if it's…you may be the longest-training crew in the history of American spaceflight by the time you fly. Do you think that gives you an advantage in, for the three of you, once you arrive in orbit, for having spent that much time together getting prepared?

I think it will be an advantage because, you know, we'll know each other really well, and, you know…we'll know pretty much what each other is thinking because we've been at this so long together. So I'd say we have a tremendous history, we have a great relationship, and so I think it'll help our activities to go much more smoothly, during the flight.

Let's talk about your flight. Flight Engineer 1 is your title-tell me what you're going to be doing while you're in space. What are your responsibilities as a member of this crew?

Well, as a member of this crew, you know, we pretty much share responsibilities; about the only thing where I have a specific location on the space station is the left seat of the Soyuz where I'm the Flight Engineer, and my training is specific for if we would ever have to do a reentry in a Soyuz, I'm responsible for the Soyuz computers and the reentry system, the engines and the docking system. So those are, so that's where we've really specialized. I think for the rest of the station systems we've been fairly evenly trained, so as far as robotics, as far as EVA, we've pretty much all received about the equal training.

Your flight's going to begin in the shuttle Endeavour when Dom Gorie and his crew deliver you to the space station. The first time station crews were swapped out it was done one at a time over several days; in August, the Expedition Three crewmembers all moved onto the station all on the same day. How's the exchange going to be handled between Expedition Three and you, and what's the rationale for selecting one method or the other?

Well, the first crew exchange was driven due to their flight program: they were doing a number of EVAs out of the shuttle airlock and the upcoming station crew was involved in those EVAs. And so they couldn't transfer early, and so they had that staged handover, which, you know, was I think a relatively difficult thing to do. With Expedition Two to Three they did it all pretty much on the same day-we're going to be doing the same thing. And that way what you do is you get a clear delineation of who are the station residents versus who are the returning crew, and so you don't have sort of a mixture. But it was the Expedition Two way of doing, way of transferring crewmembers was really driven by the requirements of their flight program.

And once you're on board it's scheduled to take four, five days to unload the supplies that are coming to the station in the cargo carrier Raffaello, as well as other supplies in the shuttle middeck. Can you describe for us what the kinds of supplies and logistics that are going to be involved, and what you'll be doing as all this material is delivered onto the station.

Well, I'm one of the loadmasters. So Linda Godwin and I will be working together to make sure that all the cargo comes off of Raffaello and then all the cargo that's going back down gets onto Raffaello. And so it's like moving into a house where the old occupant is moving out, you're moving in, but you're using one truck. And so you have to make sure that you don't get your boxes mixed up. And so we'll be working very hard to make sure that we don't do that. And then Frank Culbertson and his crew are going to have to help us out by getting their pre-packed items ready to go, and so as the upcoming boxes come off, you know, Frank's boxes will come in, and so it'll be kind of a constant logistical activity as we make sure that everything coming up comes up, everything going down gets stowed. The things we're bringing up of course food, hygiene supplies, clothes for five months for our three crewmembers, and then also things like the solid-state memory for the command and control computers, the outlets that we'll be installing-just a variety of pieces of equipment that we'll be working with during our stay in orbit. And of course science experiments: we'll be bringing up some new science experiments, we'll be refurbishing old experiments. For example, Frank's doing a cell biology experiment, and I'll be doing the, sort of the second part of that, and so his samples will come on board to go home, my samples will be coming up.

There's time scheduled during the docked phase of STS-108 for what is called handover, and I'm guessing that this amounts to more than just getting the nickel tour of the space, of the building, if you will; give me a sense of what it is that you folks do and talk about during this period. How does it help you get off to a good start once Culbertson and his crew go home?

Well, what we're going to do during that handover period is to find out how the station is really operating. You know, first we'll start off with where things are stowed, you know because we don't really have a comprehensive model, a mock-up, that really represents the station, either here or in Russia. So, you know, the only unit to really [train on] is the one that's in space. And so we will go and look to find all the different items that we need on a day-to-day basis. And then we'll go with each piece of equipment that we use on a day-to-day basis, like the treadmill: you know, how does it work, what are the idiosyncrasies to find out about; here's the SSRMS-you know, how best to operate that. And so, we'll go system by systems and find out, you know, what things are different than what we were told on the ground.

I'd like to try to see if I can get you to help us understand better what life is like, day-to-day, for a member of the space station crew on a long-duration mission. If there's such a thing as a normal day on board a space station, what do you expect it will be like?

Well, it's, you know, we've touched on all the different things that we'll be doing, and so I think things that are constant, that we will see every morning, is we will wake up to the morning mail, and we'll have our daily plan laid out for us, which we will review, and then we will have a telecon with the Mission Control and we will discuss this daily plan, make sure that we understand what the ground wants us to do, and then we'll go forth and execute that. Now, included every day will be exercise, either on the treadmill or on the exercise bike that we have up there, or on the resistance device-it's sort of like a Soloflex in space. But what we found out is the combination of the treadmill, the bike, and this resistance exercise has been very, very good for the crewmembers and the last two crews that have come down have come down in excellent shape. So, planning, exercise, and of course meals-you know, we'll have three meals plus a snack-and then, you know, the work that we do…whether it be operating the arm-and that usually every Thursday will be "arm day"-so we'll be driving the robot arm checking it out; we have PAO activities, I think, Tuesdays and Thursdays as well; so, so we have those things, and, then our science experiments. Some are front-loaded, in the beginning of the mission, some every month. So…but it's that planning conference, exercise, food, and then whatever work comes up.

Let's talk about different kinds of activities during your mission, especially, as you've just mentioned, during those first few weeks after Endeavour leaves, your schedule calls for attention to be on station science. How do you see the space station's scientific mission being advanced during your five months in orbit?

Well, we'll continue the work that Expedition 3 started with cellular biology experiments; we also have a plant growth experiment where we'll actually go and harvest plants; we have some…human experiments that we'll be participating in-these are similar to ones that Expedition Two and Expedition Three are participating in-and so for the human experiments, we will be increasing the number of subjects. And so when the experimenters gather their data they'll be able to make some better assumptions based on a, you know, bigger value of participants. And so, I think the culmination of our participation plus Expedition Two, Three, Four, Five, will allow us to really make some headway and get some answers to some of the scientific questions.

Overall, are you seeing your scientific mission as an extension, or an expansion, of what's come before you?

I think it'll be an expansion. I think we'll have some additional work that we'll be doing on orbit plus a continuation of the human experiments and the cell biology. But it'll just keep getting a little bit bigger each time.

Tell me about some of the investigations. You've got nearly thirty different ones, I think, during your whole time on board-what different areas of science are going to be represented in the research program here?

Well, we have the cellular biology which is a local program here at JSC, and so we'll be growing different cell lines in space; I think I'll have up to twenty-four different samples that we'll be growing during a, I think about a fourteen-day period at the beginning of the mission. And this is an experiment similar to what Frank's doing now. And we hope to improve our understanding of how cells grow in space, and understand also more about the cellular structure because, in space, these cells actually grow in three dimensions, where on the ground they grow in a plane. And so, when they grow in three dimensions the cells can get, they can build little structures and be more representative of cells in the body. And so it's an exciting program, and we're looking forward to that. And then also we have our human experiments-we're going to be looking at renal stone formation-or, hopefully, no renal stone formation-but the things that we might use as countermeasures further down the line. That pulmonary function in space, and also pulmonary function before and after EVAs to see if there's an effect of working at a much lower pressure when we work in our spacesuits and see how that affects our, you know, our pulmonary function. So, it's sort of a smorgasbord of activities.

How do you feel about being the lab rat?

Well, I think that's something that, you know, that…we've been human subjects since we started as astronauts, and so this is just a continuation of that with different experiments, and I guess the difference is, of course, these experiments extend for six months before the flight, during the flight, and then, of course, afterwards.

There's a healthy portion of your time on board spent working on these scientific experiments each week. Apart from being the subject of the experiment, what is it that you actually do on board to conduct these other experiments and investigations? What does your job entail?

Well, we're like a lab technician: we'll be performing media exchanges for samples, we'll be checking to ensure that the samples are growing as planned, we'll report to the ground if there're any anomalies, we have status checks to perform every day. So, it's just, once we get things started, to make sure everything progresses per the timeline, and then at the end to make sure that we terminate the experiment properly so that when we bring the samples home, the scientists'll be able to make the proper evaluations.

As part of your training for this mission you're also training for a spacewalk, to be conducted along with your Commander, out of the station's Docking Compartment. You have spacewalk experience, about seven hours worth of spacewalking experience, from your first shuttle flight; are there some serious challenges involved in transferring the experience that you have-shuttle spacewalking-into space station spacewalking?

Well, I think, you know, we'll be doing these our first two spacewalks in the Orlan spacesuit, which is the Russian spacesuit, which is an excellent spacesuit, and we've received tremendous training on that spacesuit in Russia. I think that we'll be working at a little bit higher pressure in the Orlan suit, and so it'll be a little bit stiffer, and so that'll be a physical challenge. But once we get out and begin our work, it's very similar to the work that we've done in the EMU. So, and we train in the same kind of environment, under water, so a lot of the things we do in the EMU is easily transferred to working in the Orlan.

Let's talk about the spacewalk. Describe the jobs that are on the schedule for you and Yuri during your spacewalk.

Well, the spacewalk that Yuri and I will do is to move the first Strela cargo boom, which came up during the 2A.2a flight, and we're going to move that from the PMA to the Docking Compartment. And so, we will use the Strela that comes up in the Docking Compartment to drive us over from the Docking Compartment to the PMA, sort of lash the second Strela on, and then bring it over. So it should be a very visually interesting EVA because I'll be hanging at the end of the Strela, sort of being transferred in free space, with this other large structure. So I think it's going to be very exciting. And then once that's complete we'll be doing a sample change-out…we also have science outside of the ISS. And so we'll be changing out one of those samples. It's called a Komplast.

Within a week or so Yuri is going to make another spacewalk, this time with Dan. Tell me what they're going to be doing during that spacewalk, and what do you do inside while they're working outside?

Well, Dan and Yuri will be installing some gas deflector units onto the engines of the Service Module, and these are to try to keep the gaseous by-products from those engines from getting on the exterior of the Service Module. If you remember pictures of the Mir station, there were like deposits, kind of looked orangy-browny on the outside, and we're trying to keep that from happening. So we have these gas deflectors. We're also, Dan's going to, and Yuri, are going to install ham radio antennas so we have four of those around the circumference of the Service Module. And then we also have some, let's see, they're again, external science experiments that will be installed on the way back in. So it's quite a bit of outfitting that they'll be doing, and then on the inside I'll be helping them to get into their spacesuits, I'll be closing hatches, making sure that all the hatches are sealed and ready, and then probably try to sneak a peek at what they're doing using some of our external cameras on the SSRMS.

I understand that at the time that we're talking there's still some discussion about adding another spacewalk or two later on in your mission, after the S0 truss arrives, and those would be EVAs done in the American spacesuits out of the new airlock. What would be on the agenda for those EVAs?

Well, as you know, the S0 truss is a huge piece of truss work-it's the first piece of the external truss that will be attached to the U.S. Lab, and it's sort of the foundation from which that external truss will grow. And there's a tremendous amount of work that has to be done. And so the shuttle crew will be performing a number of those activities and if they run out of time to complete those, we will go out-Dan and I, or Yuri and I-will go out and we'll complete the outfitting of the S0. Things like there's a CETA spur which connects the airlock to the S0 to allow easy translation; you know, we would be installing that [and] some other things…there's an external charged particle detector we would install that also put it in its operating position. So these kind of things, we would just do just to help the shuttle crew out, I guess.

Let's turn our attention to that shuttle visit you'll receive during your mission. The station assembly mission 8A delivers the S0 truss and the Mobile Transporter. For starters, can you describe what those components are, and explain their importance in the assembly and operation of the station.

Well, the S0 is sort of the switching hub for all the electricity that will come from the external solar arrays once the complete truss structure is assembled. And so, and it also is the hub of the U.S. guidance and nav equipment. And so, right now we've been relying for the most part on Russian navigation systems, so we'll have a complete U.S. set once the S0 arrives. So, the S0 is a, you know, has a tremendous functionality and it needs its own updated software. Our job in this to start with, will be for robotics to take the S0 out of the payload bay of the shuttle and then install it onto the U.S. Lab. We'll then use the SSRMS to support the EVA activities: we'll have an EVA astronaut on the end of the SSRMS, and it'll probably [be] the first time that that occurs, and so we'll be manipulating that crewmember around to help him install and activate the S0. In addition, we'll also of course be helping the shuttle crewmembers get dressed and to get in and out of the station airlock, because they'll be working on our station airlock. And so we'll be getting [them] dressed, getting [them] out the door, bringing [them] back in, changing the suits, because we have two teams of EVA crewmembers, so we'll constantly be changing those suits as well.

If you could give us a…four spacewalks is a lot of material to cover, but a thumbnail sketch of what's going to be done during those spacewalks, and apart from helping them get dressed in the airlock, what you and your station crewmates will be doing inside the station while the shuttle astronauts are working outside.

Well, while the shuttle crews are outside, Dan and I, and Ellen Ochoa from the shuttle crew, will be operating the SSRMS. And normally, because the station arm is so big and the viewing is not as direct as we have for the shuttle arm, we typically have two people-one running cameras and then one actually flying. So we'll be working together on that; the other crewmember will be working generally in the airlock, and then the other thing is, because we're doing some power-downs the S0 truss, being that it is sort of an electrical hub, we'll have to mate several electrical connectors during this flight and so we have to make sure that all the electrical inhibits are in place prior to the EVA crews mating or demating cables to make sure that they're safe to be handled. And so that's another thing that we'll be doing is to make sure that those inhibits are in place. So we have a lot going on, and, of course, you know, all the other things that we have to do on the space station as well.

How does the addition of the S0 truss and its new components, how does it change or improve the functionality of the station for the remainder of your time there?

Well, the addition of the S0 truss plus the new command and control software that will come up about a month earlier will allow the U.S. to have a full guidance and navigation capability equivalent to what we have on the Russian segment. So we'll have GPS antennas and also we have the rate gyro assemblies, and so we will have data from both the U.S. and the Russian segment. And it'll just make the station a more reliable station, because if one source of data for some reason cuts out, we have this equivalent data on the other side. So it's just a more robust station.

Near the end of your flight, you'll be on hand on the station to greet a taxi crew with a new Soyuz spacecraft. Tell me what activities occur on board the station during the time that taxi crew is there. Do they bring their own science? Do they help you with yours?

Well, I think that, you know, that the primary job of the taxi crew is to bring the new Soyuz. The Soyuzes can stay on orbit for about six months, you know, plus or minus a month; they have some limited-life components, and so we trade these Soyuzes out. And so the first order of business will be to take the seat liners from the old Soyuz that belong to our Expedition crew, move those to the new Soyuz, and then the seat liners from the new Soyuz, move those to the old Soyuz. And so we have to do that swap. And then, I'm not sure if they have their own science agenda; I suspect that they will and so they will probably go and begin their science program.

When your ride home and your replacements arrive at the station next spring, at that point you'll be working with your third shuttle crew and second other station crew of your mission. What is it like to have to train with, to have that many different elements of the mission, that many different groups of people? Is that hard to keep it all straight?

Well, it is very difficult to keep it all straight and just…if you add to that the fact that we were the backup crew for Expedition 2, so we had to do the training with all the crews that they worked with also, so, I mean, in one hand, it's very difficult to keep it all straight; on the other hand, it gives us a tremendous advantage in seeing all the different operations that have occurred and to train significantly on each of those. So we have a tremendous amount of SSRMS experience, for example, and from an EVA perspective we've seen lots of different configurations, so we're very familiar with the exterior of the space station from our EVA training. But it is a challenge, but what we've done is…typically our training for space shuttle has been very task-specific, because the tasks are well-defined and they're limited in scope. With so many tasks, we've really relied on more skill training so that we know how to do categories of tasks. And so this new category comes up, for example, the installation of the Mobile Base System; you know, it is another SSRMS task and we approach it that way. And you know, it differs a little bit from the S0, it's not as massive but, you know, we follow our procedures, the procedures are similar, the types of things that we do, the types of things that we look at. And so, in that way, we can handle this massive amount of activity.

By the time you, Yuri, and Dan leave the International Space Station, what in your opinion will have had to have occurred for you to consider Expedition 4 to have been a success?

Well, I think that you know, of course that you know, we come down in, we return in good physical shape-I think that's one of the most important things-and that we leave the station in better shape than we got it. That it will be a bigger station, a more robust station, and then that we have completed successfully our scientific program.

At this point it's been about one year since the first permanent residents of the ISS arrived on orbit. Now we're at a point where we're pretty routinely swapping out crews and delivering supplies and conducting science on a station that's virtually self-sufficient. Finally, Carl, give me your perspective: what are your thoughts on where you see the International Space Station program taking us in the short term and in the long term?

Well, in the short term, of course, we will continue the assembly of the space station, and I think we'll continue to build out that external truss, to provide the power that we need then for the additional modules that will be coming from Japan and from Europe, and then additional modules perhaps, on the Russian segment as well. So that activity will continue. And I think at some point we'll expand the crew to probably six people so that we can have a more robust science activity as we have these additional laboratories available. So, short term, I guess continue the building, and then long term a bigger crew. I also see that we'll begin more commercial activities on board the station as well as the, as we can finish building and then we get into a more mature operation, we'll see more commercial ventures coming on board. And that'll be, I think, a tremendous challenge.

Eager to get started?

You bet.

IMAGE: Expedition Four Flight Engineer Carl Walz
Click on the image to hear Expedition Four Flight Engineer Carl E. Walz's greeting (366 Kb).
Crew Interviews

Curator: Kim Dismukes | Responsible NASA Official: John Ira Petty | Updated: 09/04/2002
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