Q: There are hundreds of thousands of pilots and scientists out there in the world, but only about 100 American astronauts. What made you want to be one of them, to be one of the people that fly in space?
Image at left: STS-115 Mission Specialist Dan Burbank awaits spacewalk training at the Neutral Bouyancy Laboratory in Houston, TX. Photo Credit: NASA
Preflight Interview: Dan Burbank
A: I first got interested in the space program back during the Apollo era. It was just before my eighth birthday when Apollo 11 happened and it made a, a tremendous impression on me, as it did a lot of folks of my generation, I think. It didn’t make me want to be an astronaut, though. It made me an amateur astronomer; it made me always interested, again, in the space program from that point on, but it never occurred to me, at that age anyway, and really for quite a few decades afterwards, that this was something that I could do. It wasn’t really until I was already in the Coast Guard and a Coast Guard pilot. A fellow pilot within the Coast Guard applied to and was selected for the NASA program. It had never occurred to me until that time many years after Apollo 11 that this would be something I could do. So I applied to NASA and got an interview. I came down here and spent a wonderful week learning about the program firsthand, and wasn’t selected. Went back to flying Coast Guard helicopters and doing the things I was doing in the Coast Guard, applied again two years later, got another interview, came down, another wonderful week, and wasn’t accepted. And two years later, on my third attempt, I was accepted and came down here in August of 1996. It’s been a wonderful experience. I’ve got to be honest with myself and say that there’s so many very, very talented people that also deserve to be here, and unfortunately right now the space program hasn’t grown to the level where as many people as I would personally like have had the opportunity to do this. And I’m very fortunate to have done it. I certainly enjoyed my experience in the Coast Guard and, and flying. But flying in space has been a dream come true but again, a dream that, when I was 8, I never really thought that I’d, one day see.
Tell me about the place you grew up, Tolland, Conn. Tell me about that town.
Well, I was born in Manchester but I, most of my years growing up were in Tolland, about 20 minutes east of Hartford, kind of a real “small town” sort of atmosphere. I just kind of grew up like most other kids my age. I had a nice, tight-knit group of friends in high school. Some of them were interested in a lot of the things I was interested in, including music, for example, and in space and astronomy. When I was growing up I wanted to be in the Coast Guard; I wanted to go on Coast Guard small boats and rescue people in the surf. I applied to the Coast Guard Academy, I got in, and I graduated in 1985. When I first went there, initially, again, I wanted to be on Coast Guard small boats and do search and rescue. As I learned more about the Coast Guard Academy, when I was first there, I realized much to my surprise that the, the only people in the Coast Guard that don’t go on Coast Guard small boats are officers; you know, you’re too senior to do that. The Coast Guard enlisted personnel are the ones that get to do those kinds of hands-on rescues. If you want to do hands-on rescues in the Coast Guard, the only way you do that as an officer, anyways, is as a helicopter pilot. I’m not one of these folks that grew up as a kid always knowing I was going to be a pilot. In fact, I’d never really thought about that. I saw myself at sea. But early on in my Coast Guard Academy days the idea of flying kind of occurred to me, and I loved it; it was absolutely wonderful. It was a great experience. I spent my first tour after the Academy on a ship but after that went to flight school. It wasn’t until after I was out of flight school that I thought about applying to the space program. I had some great experiences flying search and rescue missions out of North Carolina, out of Cape Cod, out of Sitka, Alaska, before I came here to NASA and flew a different kind of vehicle.
Got any idea what it was that, as a kid, made you want to go to sea?
Well, it’s going to sound a little bit silly. There was an old Walt Disney movie that I saw about the same time, probably, that I watched the Apollo 11 landing. It was a movie called “The Boatniks.” It wasn’t animated, it was just one of these silly kind of farcical Disney movies, and the main character in the movie was a guy that came out of the Coast Guard Academy, went to a ship, and had a series of adventures and misadventures and other things. It made a real impression on me, and that’s what I always thought I would do. Not necessarily the misadventure part but, but at least the, the Coast Guard rescue, a piece of that. It was a, just a great tour. I’m still in the Coast Guard, of course. I just don’t get a chance to fly on helicopters as much as I’d, as I’d like.
You were talking about your hometown and the friends you had and it sounds like “small town America,” almost out of an old storybook. Do you see that that place and the people there contributed into making you the man you are today?
Without a doubt. I certainly credit my folks for a lot of that, my parents. Dad was a school teacher. Mom used to substitute teach at schools as well. Growing up in that kind of environment, spending a lot of time hiking, camping, fishing, horsing around with the friends I grew up with and playing sandlot football … in the winters hockey at the pond at the base of our street, all those kind of experiences, I think probably made me understanding the importance of family, of friends. When I go to schools a lot as we all get a chance to do with the program here, one of the most common questions I get asked by kids is, "How can I become an astronaut?" I tell them that to my thinking there are basically three things they have to do. And the neat thing about this is the same three things are the things that they need to do if they want to do almost anything else that they’re really passionate about. I tell them the first is, they have to work hard. As, we discussed earlier, not very many people get a chance to fly in space and get a chance to come down here and do this. A lot of people want to do it, so it’s very competitive. So for all the various backgrounds that we come to NASA with, most of the people come here are at the very top of whatever field they’ve come from. And so you have to work hard at whatever it is you’re doing. Certainly NASA doesn’t just have military test pilots anymore. We’ve got pilots, we’ve got physicians, we’ve got lots of scientists, we’ve got teachers -- people from all different kinds of backgrounds, engineers as well, of course. All those people again are really committed to what they did and did very well before they came here. You have to work hard to do well, to compete well to come to NASA. If you want to be a surgeon working on a trauma team in an inner-city hospital, for example, you’ve got to work hard to learn your craft. The second thing I tell them they have to do is be good. Flying in space is a team sport. Being a trauma surgeon’s a team sport. Playing violin in a symphony orchestra is a team sport. Almost anything you do in life, you’re going to do with the help of others on a team. And particularly for flying in space, your life is in the hands of your crewmates, and their lives are in your hands as well. So you’ve got to genuinely care about them and they’ve got to care about you. I think being a good person, being reliable, being trustworthy, and, and genuinely caring about people, is real important. The last thing I tell them is don’t give up. There’s almost nothing I’ve ever done in my life that I succeeded at it the first time, including going to the Coast Guard Academy. It took me two applications to get there. It probably took me, I guess, two or three to get into flight school, when I was within the Coast Guard. It took me three applications to come to NASA as well. So, I, if you’re going to come to NASA expect not to be selected the first time. But almost anything else you’re going to want to do that’s really worth doing in life you’re going to have to try a series of times because it’s not going to work out at first. So I tell them all those three things. I think all those lessons I learned at one level or another growing up in, in Tolland, in Connecticut. They’re probably lessons that all of us have learned at some stage in life as well.
You touched on one other point I want to ask you about, and that’s the danger of flying in space. What is it that we get from flying people in space that you think’s important enough that you’re willing to take that risk?
This is something that I think certainly all astronauts and the families of the astronauts, really have to grapple with and come to terms with. As we painfully learned and been reminded, flying in space is a very dangerous business. Flying search and rescue missions for the Coast Guard there were times when I’d go out and the weather wasn’t so great. It was the kind of thing where you could do the calculus yourself. The cost-benefit kind of thing was very black-and-white. You were going to be in a position, potentially, of putting your crew and your vehicle in harm’s way with the real potential of saving lives, and it was very clear-cut, kind of, kind of math. Flying in space is a little bit different. It’s not the kind of thing where you can say, "Well, I will accept this risk because of this benefit that, that I expect to get out of it. The benefit’s global, the benefit is basically paving the way to make future space missions safe and again, because, because you personally feel the commitment that this is where humankind is bound for. If you look back in the earliest days, as we were settling this country, for example, whenever we tend to push the boundaries and to settle new frontiers it always comes with a lot of hazards until we eventually work out the kinks and make things safer. But in the end it’s a, a great benefit for society. I think flying in space and the space program and the benefits we’ll get, both commercial but also the, the intangible benefits for expanding the reach of humankind, I think are worth the risks. We’re really at the very beginning of opening this door to space exploration. But in a very few decades, hopefully we’ll not just put footprints on the moon but put permanent outposts on the moon that will lead to larger settlements and hopefully we’ll do a similar thing on Mars and beyond. It’s a really exciting time right now. The shuttle, with its challenges, the space station with the things we’re learning about building that, all those experiences are going to stand us in good stead. The risks, I think, are going to be well worth the reward.
You are a Mission Specialist for ISS assembly mission 12A. Give me a summary of the goals of this space shuttle mission and your jobs on this flight.
In a nutshell, our mission is going to be the resumption of assembly of the International Space Station. Post-Columbia, we’ve had a lot of work to do to get the shuttles flying safely again. Our mission’s going to bring up the next big piece to the International Space Station to allow us to add power capability to the station and thereby be able to add future elements, including the international partner elements.
I’m the mission specialist 2, so for ascent and entry my job is to be the flight engineer on the flight deck. I kind of sit between the commander and the pilot and help with trajectory monitoring and systems monitoring, things like that. For the on-orbit phases, I’ve also got some responsibilities with the shuttle systems, to kind of back up Brent [Jett] and Chris [Ferguson] with their duties. I’ve also got the responsibility of being the prime shuttle robotic arm operator. We’ll use it to pick up the P3/P4 payload and hand it off to the station arm for installation on the International Space Station. I’ve also got some other miscellaneous duties, as we all do. One of those is also managing the on board network of our laptop computers that basically support our missions with various software applications.
Gonna do a little spacewalk?
I’m going to do a spacewalk as well. So we’ve got a series of three of them for the mission, and for the second spacewalk, or EVA, Steve MacLean and I will go out and help with some of the activation activities for the P3/P4 Truss.
You have been training with these same crewmates for this same mission since February of 2002. How have you guys kept focused over such a long stretch of time?
Well, first off, I have to say that training for a space shuttle mission is an awful lot of fun and it’s interesting, intrinsically, in and of itself, so it’s something you can do for a long time and certainly not get bored with. In our case, too, the mission has grown some. Certainly for all the missions post-Columbia we’ve added a lot of capability to the shuttle. We’d added new requirements to inspect and do various things to certify that the Thermal Protection System of the shuttle is safe for re-entry. So that’s added a lot of complexity to the mission and it certainly has kept us busy even into these last months just before we fly. There’s been a lot on our plate. The mission, even at the very beginning, with bringing the P3/P4 Truss up to the space station, was all, already fairly complicated. It hasn’t been hard to, to keep our interest and to keep ourselves focused on getting ready for this.
As you mentioned, implementing changes recommended by the Columbia Accident Investigation Board has been a big part of the reason that your training period has extended so far. On the subject of those improvements, are you satisfied that the things that have been done to this point have led to a real improvement in shuttle safety?
I am. I think everybody on our crew is. I think everybody that’s worked on improving the shuttle and making it more robust, removing sources for liberation of foam that’s a threat to the wings of the shuttle and the underbelly of the shuttle -- a lot of folks have put a lot of work into it. We’ve got a chance to monitor that and watch that firsthand. I think everybody’s very satisfied that the shuttle is as safe as it can be before we fly. Certainly, we would, we’d have some reservations before climbing aboard if that wasn’t the case. I think we’re all ready to go.
There are new post-Columbia tasks on the mission, starting very early on in the mission that you didn’t have when you flew the first time. Describe some of these inspection-related tasks to look for the possibility of any damage done during your launch.
First just to back up a little bit, when the shuttle launches, we’ve added a lot of capability to monitor the shuttle’s ascent, for foam that’s liberated or if we have an incident where, for example, the shuttle were to strike a bird. We’re able to monitor, with very, very high resolution from cameras on the ground, cameras in flight and also cameras on board the shuttle itself. So the first goal is basically to give you the capability to see if anything comes off the shuttle and potentially poses a threat. But the real test is once we get on orbit there’s always the chance that something might have come off that we didn’t see and might have struck the wing, for example. Once we get on orbit now we’ve got some great tools that allow us to go and inspect, end to end, the entire orbiter, particularly the most critical areas -- the leading edge of the wing, the nose cap, and certain areas on the underbelly. After we get on orbit, the next day is almost entirely dedicated to doing an end-to-end inspection of the shuttle underbelly, wing, and nose and also the upper surface. We do that with what’s called the orbiter boom sensor system. It’s stowed on the starboard rail, much like the shuttle’s robotic arm is stowed on the port rail. It doesn’t have joints, it’s not articulating, but it does have at the end of this boom some sensor systems, including a laser dynamic range indicator that allows us to get good high-resolution two-dimensional imagery looking for cracks, probably down to as small as maybe a tenth of an inch. We’ve also got another sensor there called the LCS, the laser camera system, which gives us the capability of generating three-dimensional data and find cracks or potential damage to the reinforced carbon-carbon leading edge of the wings down to maybe to two one-hundredths of an inch, in the best conditions. We’ve also got some other cameras out there. We’re going to spend a day with this boom system, with its sensors, attached to the end of the shuttle’s robotic arm, we’re going to spend an entire day scanning very, very closely and deliberately all the areas that we’re most concerned with. It’ll give some time for the, the people on the ground, the imagery experts, to analyze all that data and for us all to be sure that the shuttle’s safe to come back home again.
As the arm operator can you characterize that task? As you say, it’s very lengthy. It takes a, a long time, but it’s also pretty precise.
It is. To be fair, the computers on the shuttle are actually going to command most of the arm motions. For myself, Chris Ferguson, our pilot, and for Steve MacLean, the three of us kind of have the prime responsibility of doing that task on Flight Day 2. Our job really is mostly a monitoring task. We’re going to command these various automated sequences where the shuttle arm with the boom attached to it will scan all these areas I talked about through these preprogrammed trajectories. We basically do something that tends to be a little bit difficult for humans, and that is to, over a long period of time, monitor and make sure that, that we’ve got good clearances and that the boom through some possibly errant motion of the arm doesn’t present a threat to the wing and to the underbelly. The way we’ve sent it up through this day is to rotate our tasks and back up each other, the shuttle’s computers and the robotic systems and make sure that we get good data. It’ll be a little bit challenging, it’ll be a very long period, but it's something that’s real critical to do.
The primary cargo on this flight is a new component of the station’s truss structure called P3/P4 Truss. What is it, what’ll it do, why is this important to the International Space Station?
P3/P4 is of, kind of an obscure term, I suppose. The space station, essentially, has most of the pressurized modules oriented along its length. We’ve got a laterally-oriented truss segment, which starts out with S0 and then it extends out to the right, starboard one, starboard two, starboard three and four … and on the port side, we’ve already got P1, which is the port No. 1 truss element, and we’re going to add the port three and four, which attaches to it. The business end of this truss segment is a set of solar arrays that are much like the ones we already have on the very top of the space station now, and these will extend out to 240 feet and give you the capability of generating a lot of power from the sun’s energy. That power can be stored in batteries and used during the eclipse periods, when the space station passes behind the Earth. When space station is fully assembled, it will fly over the Earth in what we call a local vertical/local horizontal attitude airplane mode with the truss elements oriented laterally, and you can almost imagine the pressurized elements as the fuselage of an airplane. What that means is to gather the sun’s energy, the solar arrays are going to have to track the sun as it passes overhead, as the station’s passing roughly east to west. As the sun passes overhead, the solar arrays, through what’s called the solar alpha rotary joint, which is the middle section of this P3/P4 Truss, will basically track the sun and, and provide a perpendicular orientation to the sun and gather the most energy. The component that’s the business end of allows you to do this tracking, active tracking, of the sun. During the first EVA we’re going to prepare the solar arrays to be deployed. During the second EVA, when Steve and I are out there, we’re going to remove a series of launch restraints and allow this joint to track the sun. It’s a new component that we haven’t flown yet, and we, in a very deliberate fashion are going to remove these 16 launch locks and then a series of launch restraints, six of those, to allow this joint to rotate freely. On the third EVA we’ll do some last-minute preparations. We’ll deploy a radiator. We’ll do some final preparations of the structures that support the solar alpha rotary joint. At that point, after those three EVAs, and with the wings deployed, the P3/P4 Truss will be in a position to generate power and probably add about 40 percent to the power capability to the station.
Is it simply additional power-generation capability, or is it backup that this provides?
Well, at this stage the space station is set up with the P6 arrays, which are at the very top of the station -- ultimately down the road those will be relocated outboard of this P3/P4 Truss that we’re bringing -- provide most of the power for the U.S. segment and also some power, as needed, for the Russian elements. Those solar arrays would impinge upon the trajectory of the P3/P4 arrays. So at this stage, after we finish this mission, we will have the solar array rotary joint basically in a fixed, locked position oriented straight towards zenith. Afterwards, the port wing of the P6 array will be furled, and that will allow our array to track the sun and generate more power. In the immediate near term power that it is collecting will mostly be in support of the P3/P4 components. Once we furl that 4B array on the P6, it’ll allow us to, you know, use that array to, to track and generate power, and then we can add the, the follow-on elements to the space station, including the Node 2, the Japanese and European modules.
The preparations for the spacewalks on this mission have something that will be brand new. It’s called a campout pre-breathe. Tell me about what that is and, and how it works and, and why you do that as opposed to the way we prepared before.
Image at right: STS-115 Mission Specialist Dan Burbank participates in crew bailout training at the Space Vehicle Mockup Facility in Houston, TX. Photo Credit: NASA
To provide a reasonable amount of mobility in the spacesuit, we have the suit depressed relative, at a lower pressure relative to what we’re used to here on Earth. Instead of 14.7 pounds psi, the suits operate at around 4.3 pounds per square inch. In the suit we breathe 100 percent oxygen. There are concerns about having nitrogen off-gas within our bloodstream and present a hazard -- embolism and “the bends.” To prevent that we have a couple of different methods to purge the nitrogen from our systems before we take ourselves down to these lower pressures. One way is to do a prolonged pre-breathe on a mask of 100 percent oxygen. Another way, and we've done this on the shuttle, is to reduce the pressure in the ambient environment to about 10.2 psi. Do that for a long enough time and then we can reduce prebreathe time. There’s another way to do this. You can accelerate the rate of nitrogen reduction by exercising while you’re breathing oxygen. So on the space station for our EVAs we’ve done what’s called an exercise pre-breathe protocol. The crews have exercised on a cycle ergometer at the same time they’re breathing 100 percent oxygen. The increased blood flow tends to purge the nitrogen at a fairly quick rate, so we can do a reduced pre-breathe. When you look at all the activities preparing to do the spacewalk, including the complications of doing an exercise pre-breathe and all the involvement of the crew to support that activity -- and then, of course, donning the spacesuit and heading out -- we actually can save some time by doing what’s called a campout pre-breathe. That is spending the night in the station’s airlock and depressing that down to 10.2 psi, purging the nitrogen more like we’ve done in the shuttle and for past EVAs. We can take the entire shuttle volume down to 10.2. And then we can wake up the next morning and the crew can put on an oxygen mask, re-pressurize the [airlock] to the ambient conditions and then start donning the suit and doing the various EVA prep activities and go out and do the EVA. We can end up saving ourselves 40 or 45 minutes worth of time that way. That doesn’t sound like a lot but for our mission, because of all the activities that we have to do particularly around the EVA days, it’s very difficult for us to meet what we consider to be a reasonable crew day for all the crewmembers. We end up going very, very long. For example Flight Day 3, that’s rendezvous day, we basically will get up early on this third flight day and the entire crew will spend the first half of the day catching up to the space station, doing a series of burns to synchronize our orbit with space station, and then docking with space station. It doesn’t end there. We meet up with the space station crew, we do an emergency briefing with them to learn where all the equipment is on space station, then we get right back to work. In our case Chris—Fergy—and I will remove the payload, the P3/P4 payload, hand it off to Steve MacLean, who’s now on space station operating its arm. Then we will get ready to do this campout. That entire day, from rendezvous to the P3/P4 handoff to the station arm to the campout pre-breathe, is a very, very long day. The following day we get up early again and complete the installation of P3/P4. At the same time that that’s going on, Joe [Tanner] and Heide [Stefanyshyn-Piper] are going out to do the, the first EVA. So those two days, for the entire crew, end up being very, very long. Forty-five minutes for us is a, is an awful lot of, of time to, basically, ease the workload for all of us. Not doing the exercise pre-breathe simplifies the early morning activities. At the same time that Steve and I are, are supporting the P3/P4 install, Heide and Joe are basically getting suited up and ready to go outside. We don’t have the extra complications of doing exercise pre-breathe. In the early days of space station the intent had always been to do a campout kind of a protocol. This gives us a chance also during this mission to try that out, test it out, make sure the station environmental control systems can support that well. For future flights they’ll have the capability and the data to support a decision to perhaps go campout or do the exercise protocol. So it gives us basically a serious of options for future missions.
Let’s talk about the delivery of your, your primary cargo, P3/P4. You touched on it, but give me a, a bit more detail, starting with those robot arm operations after docking up to the point where the first spacewalk begins. What is it that you guys have to do?
Well, the P3/P4 payload, it’s about a 35,000-pound truss element, with the, a rotary joint, a series of furled solar array wings, batteries, all these other components. We can keep it in the payload bay for a long time. When we remove it from the payload bay we’ve got some thermal issues. We’ve got a clock that we basically will track beyond which we need to get that payload handed off and installed to space station and then connect some utilities, some power umbilicals, between the P1 and P3 to support keep-alive heater power for some of the components on the truss. Initially our plan with this mission had been to do the rendezvous on Flight Day 3, and then the following day, Flight Day 4, which would be EVA 1 day, do the unberth, the handoff to the station arm, and the installation to the station. Simultaneous Joe and Heide would go outside and get ready to connect these umbilicals and stop that thermal clock. Again, we’ve got a really long timeline. That day it was inordinately long. We worked with some of the folks that do the thermal analysis for us, and there was the capability to move that initial handoff -- this is while the payload is on the shuttle arm, getting ready to hand off to the space station -- off of Flight Day 4 and put it onto Flight Day 3, the rendezvous day, at the end of that. So we’re going to rendezvous, have our briefings with the space station crew; and Chris Ferguson and I will go back to the shuttle flight deck. We’ll use the shuttle’s arm to grapple the P3/P4 Truss. We’ll release the payload restraint system that attaches that truss to the shuttle’s payload. We’ll remove it from the payload bay, and take it over the, the port wing, the left wing, of the shuttle and present it to Steve, who will be flying the station’s robotic arm. Now it will spend the night on the space station arm, oriented such that we’ll be able to extend the thermal clock safely through that night and be able to do the install the following day. The following day, Brent will be helping Joe and Heide get in the suits; and Chris Ferguson will be over with Steve MacLean helping him out in the Lab of the International Space Station, flying the station’s robotic arm. I’ll be on the shuttle flight deck providing camera views to support Steve and help him align and orient the P3/P4 Truss to do the installation. You’ve probably seen a lot of the pictures where there’ll be white circles with a black dot in the middle of it or in some cases a black circle with a white dot in the middle, and these are kind of oriented in various places on the space station. The Canadian Space Agency with their contractors developed this system, the Space Vision System. It allows us to use cameras to generate a computer solution that’ll give the operators that are flying the space station’s robotic arm -- typically but in some cases the shuttle’s robotic arm -- orientation, alignment cues, to very precisely locate elements that are being mated to other elements so that we can get them in, into what we call the capture envelope, where they're ready to be physically latched together. It’s a, basically, a photogrammetry system that does this. So we’re going to actually generate some of these images on the shuttle flight deck, ship those over to Steve, who will use those, with Fergy’s help, on the space station deck to precisely align the P4 Truss, P3/P4 Truss. They'll get it in an orientation such that it can be attached to the P1 Truss. Wile all this is going on, Joe and Heide are getting ready to go outside the airlock and quickly connect the electrical cabling that’ll provide the heater keep-alive power for the element.
And, that’s really, is that the task for them on the first spacewalk is to plug it in?
That’s, that’s one of the major tasks, and Joe’s going to be doing that. At the same time that’s going on, Heide’s going to be out on P4, and she’s going to be releasing a series of launch restraints that basically contain the solar array blanket boxes. Those assemblies and restraint. So while Joe’s connecting some of the power utilities Heide will be releasing these launch restraints; the ground will be doing a series of commanding, turning the heaters on for example, and then they’ve got a series of other activities including the actual deployment of the beta gimbal assemblies. These rotate the solar array blanket boxes so we can deploy the solar arrays a couple of days later. When we initially looked at this it was going to take about three EVAs before we’d have the P4 Truss and the P3 solar array rotary joint ready to deploy the solar arrays. With a lot of work with the people who train us for the spacewalks and the PHALCON [Power, Heating, Articulation, Lighting and Control] flight controllers, the people who command all the electrical power systems on this truss element, we were able to figure out a way to fit all the critical tasks down into two EVAs, so we can do our solar array deployment after the, the, the second EVA, instead of the third.
OK. Well, let’s don’t get ahead of ourselves. Let’s don’t forget EVA 2. I don’t think you’re going to forget it, are you?
No, I won’t.
What's it been like getting ready for this and thinking about the first time you’re going to float outside a spaceship?
You spend an awful lot of time practicing getting ready for the EVAs. We work in the Neutral Buoyancy Lab that NASA has out here at Sonny Carter [Training Facility] near the Johnson Space Center. You spend a lot of time underwater working in a big pool, 100-by-200-by-40-feet deep, where we’ve got the space station elements down there. We’ve got all the tools, the power tools, we’ll actually use; we’ve even got robotic arms that we can incorporate within our spacewalks, just like we will on the real day. So the idea is that by the time you actually go outside to do this for real, you’ve actually been through it time and time again, in our case, the course of four years. EVA 2 is a little bit different than EVA 1. EVA 1’s got a lot of variety, there’s a lot of, there’s the power connections that have to be done, the launch restraint removal and a lot of other different preparations that extend from P1 all the way out to the end of P4 for Joe and Heide. I mentioned the solar array rotary joint, which, or solar alpha rotary joint, which has got all these launch restraints on it. Steve and I are going to spend the bulk of EVA 2 removing the whole series of these 16 plus six launch locks and launch restraints. We’re going to spend most of our time right in the middle section of the P3/P4 Truss driving a lot of bolts with a lot of power tools. After all that’s done, we’ve removed all this hardware that’s kept the P3 and P4 Trusses properly oriented for launch, we’re going to deploy the SARJ braces, the solar alpha rotary joint braces, a series reinforcement structures that will help to stabilize that, that alpha rotary joint on both sides. So we’ll spend a lot of time doing that. Then, time permitting, we’ll be able to get, do some get-aheads, some of the work we’re planning on doing on EVA 3. But EVA 2’s kind of different; I mean, we’re going out with a different kind of a CO2 scrubber in the EMUs that allow us to go a little bit longer than planned if necessary. Again, we, I mentioned that we had initially planned on three EVAs before we deploy the solar arrays, and by, by fitting it down to two EVAs, we’re still kind of betting on the come and hoping that everything goes very, very well in order to get all that work done in that amount of time. So we’ve got a fairly ambitious suite of activities set up for EVA 1, and hopefully Joe and Heide will be, be able to get all that done, and then we’ve got a little bit of money in the bank on EVA 2 to go a little long if we have some problem with the hardware, because we’d really like to not have to spend another day before we deploy the solar wings here.
You got, get any advice from spacewalking veterans about what to expect when you fall out that hole?
A lot of folks that, that have got a lot of experience doing an EVA from the space station. I think, in a lot of ways, it’s different than the shuttle. The way the shuttle airlock is oriented, we typically egress the airlock towards the shuttle aft into a concave payload bay. It’s a different sensation, by all accounts, than climbing out of the airlock hatch on the space station where you’re on a convex surface. You open a hatch and maybe all you see is the Earth scrolling by below you. It can be a little bit disconcerting, I think, for crewmembers their first time out. We always budget a little bit of time on the spacewalks at the very beginning for what we call translation adaptation, to get our sea legs in the suits and kind of get comfortable with the microgravity aspect of it. From, from the time the engines quit at about 8½ minutes during the ascent phase, you’ve been floating freely in space in an intravehicular mode, inside the pressurized modules, but you’ve had a couple of days to adapt and get used to what it feels like to be in space and to applying the appropriate amount of force to do the things that you do. So that part of it, I think, will be, will be very comfortable. Operating in the suit itself, I think, will be a little bit different, although, again, in the Neutral Buoyancy Lab, all the experience you get there, you’re in a suit just like the spacesuit you’re going to go out in. There are certain things that are a little bit different about doing a spacewalk and practicing it underwater versus doing it in space, but in, in, we talk about a lot of these things amongst ourselves, but when it comes right down to it I think you just have to experience it for yourself and, and taking it slow and easy at the beginning is probably the prudent thing to do and that’s what I plan to do.
The day after your spacewalk is a very visually dramatic event when you deploy the solar array wings. Talk about the work that you folks will do along with the station crew to deploy those two solar array wings.
Deploy day, that’s going to be a great day for us. That’ll represent the culmination of, all the time we’ve spent training. But a lot of folks have spent probably a decade of work leading up to this mission, people who built and designed the structure. On deploy day itself, most of the crew will be located basically in the lab module of the space station. We’ve got a lot of monitors, TV screens, so we can see various imagery from the station’s external cameras and also the shuttle cameras. It’s the best seat in the house, Chris Ferguson will be probably the only guy back on the shuttle flight deck during most of deploy. All the rest of us, including the station crew, will be kind of huddled around the Lab robotic workstation and the cupola robotic workstation, the two sets of control stations for the station’s robotic arm. We’ve got a total of three monitors normally integral with those workstations, three each for a total of six. We’ve also got what we call V-10s, which are, are smaller monitors that we’re going to bring over from the shuttle to augment our viewing capability. We learned some things on [STS-]97, during the solar array deploy there. Things didn’t go as folks initially had planned. We discovered there was an issue with stiction. You've got this 120- or 100-foot or so long solar array that’s folded up inside these two clamshell blanket boxes. There’s what we call AO blocker. It’s a material that protects the solar arrays from atomic oxygen in space. And that material’s real important for prolonging the life of these, of these solar cells in space. In a vacuum and packed within the confines of the, of the blanket boxes over a long time, we discovered that this material tends to bind to itself. So these panels were sticking together. When the solar arrays were deployed, the panels would stick together and some tension would build up in the system. A panel or two would, would release, kind of all at once and basically present a problem for the mechanisms that, that maintain the solar arrays in a good orientation once they're fully deployed. Folks had some time to look at this and decided there’s a way that we can get around some of that. The most important thing is to spend a lot of time thermally conditioning the blanket. You deploy a little while, you expose the blankets to the sun, to allow the, the solar array and this coating on the outside to warm up. Then it’ll release in a more controlled fashion. We’ve actually done some tests on the ground that kind of support this theory. But the most important thing for us, doing this, is we want to make sure that we’ve got adequate camera views to monitor the blankets themselves as they deploy, to monitor the central mass mechanism that actually is the motive force that deploys these arrays, and to monitor some other mechanisms at the base of the blanket boxes to give us an indication if we start to have this stiction phenomenon. We have the cameras oriented at both wings as we do this and looking very close up at these mechanisms, looking more globally at the condition of the blankets themselves. We’re going to basically, in a very deliberate fashion, with the ground’s help throughout all this, deploy the arrays a little bit, warm them, deploy them a little more, warm them, and, hopefully, we believe, after just a few orbits of the Earth, have both arrays fully deployed and hopefully not have any issues with the things that we saw on 97.
OK. The following day, then, would be the third spacewalk of your mission; Joe and Heide again. Tell me about what’s planned for that.
One of the first things they’ll do is to go out and prepare the P4 radiator. There’s a radiator system that basically rejects the heat loads generated by the electronics and batteries and other things on P4. Before we can activate P4 we need to make sure that we’re in a condition to cool it, and so one of the first things they do is go out and deploy this radiator -- or get it in condition to be commanded from within the vehicle and deployed remotely. They remove some restraints. There also are some structures that we have left on what we call Face 1, which is the leading face of P4. These are the trunnion pins, for example a keel beam, we call it which is basically a restraint system that, during the launch phase, keeps the P4 and P3 oriented and safely secure in the payload bay. So, in order to finish the preparations of P3 and P4 and get them ready to be activated, and most importantly to allow the mobile transporter, which is what we use to base the space station’s robotic arm on, to travel. It travels on a, on a cart, a mobile base system and the mobile transporter. That allows it to be positioned along the length of the truss, including out on P4 itself. The keel beams and the drag link, this mechanism that restrained it during launch, would actually impede and limit the travel of the mobile transporter. So they’ve got to clear this structure out of the way. There’s a series of smaller tasks to basically prepare that face to allow the mobile transport to go out there. And then there’s some power reconfiguration things they’ll do. Then Joe and Heide will then come back inboard. We at this point plan on having Heide go out to the, the forward end cone of the Lab and install a series of antennas for the EWIS, the External Wireless Instrumentation System. It's been installed in various modules and will track things like docking loads when a visiting vehicle, a shuttle or the Progress or Soyuz, docks with space station. We’ve got these sensors that are in locations, including out on the P3/P4 Truss and now in the Lab forward end cone. Heide will install a series of antennas to talk to those sensors to route those signals back inside the Lab. While she’s doing that Joe’s going to run up to the top of P6 and do some work up there, including returning MISSE-5, a science payload. After that Heide has got some work to change out the baseband signal processor and the transponder, two components of the, of the starboard-one, the S1 S-band string, a communications string that we use to, to transmit data and voice and so forth to the ground. It’s a pretty full EVA 3, as well. There’s a chance that we might change out a SASA [S-band Antenna Support Assembly] antenna, an S-band antenna that we’re seeing some degradation in performance on orbit. So EVA 3, being the last of the EVAs, once we’ve gotten all the preparation activities for P4, you know, our, our, our mission core activities, if you will it, we’re trying to protect some time in there to do some other activities that would help out the space station and put it in a good config. So we’ll see.
It occurs to me that, despite all of that, one of the biggest differences for this mission as opposed to your first one, is that you’re going to a station that’s got people on it.
When I flew on STS-106, our job was to outfit the Service Module and make it habitable for the first permanent crewmembers in Expedition 1. We docked to a station that had no people. The lights were out, the hatches were closed and a, a lot of the systems were powered down, as you’d expect. The initial ingress was an all-hands evolution: opening 13 hatches from the shuttle all the way to the aft of the space station, and then installing a lot of equipment. But we were the only game in town. There was nobody else there when we were there. The station’s, of course, quite a bit bigger now. But for a crew of seven on STS-106, we had more than enough room for us; you’d almost get lonely. With the space station there’ll be three crewmembers and, of course, it’s quite a bit bigger. This mission’s a lot more complicated, there’s a lot more things to do, and it’ll be real important for us to have the help of the space station, you know, crewmembers to do all the things we’re going to do, and, of course, it’s their home and we’re, we’re hopefully adding a little bit of capability to them, with their help.
This mission restarts the major assembly of ISS after more than 3½ years. What’s the significance, do you think, of the partner nations getting back to the point of building the space station again?
First off, this payload, P3/P4, is going to allow you to add capability, add power to support the addition of future modules. So this is truly the resumption of the assembly of space station. All the partners have been standing by patiently and, to a large measure, helping get us through this period where we’ve done without the shuttle, done without all that logistics resupply capability for the space station. We’ve got a lot of modules that are waiting and ready on planet Earth to be delivered to space station. I’m sure it’s no understatement to say that both Europeans and the Japanese would be very happy to get their modules added to space station. Hopefully this will be doing a little part to make that possible.
The Vision for Space Exploration sees way beyond the space station that you’re helping to build in Earth orbit right now. Dan, tell me, what’s your philosophy about human exploration of space?
I think anybody in this business is deeply committed to the idea of making humankind a spacefaring people. We’ve been traveling in space for quite a while. We’ve spent a lot of time in low Earth orbit. We have spent some years exploring our nearest neighbor, the moon. Everybody here at Johnson Space Center, and I know our partner countries as well, are real anxious to see us extend our reach, humankind’s reach, beyond low Earth orbit. The great legacy, I think, of Columbia and the 107 crew is that now we’ve got a national commitment to do just that, to go back to the moon, this time to stay, and to go on to Mars. The space station’s given us a lot of experience in how to do complicated things in our case in a near-Earth environment but allow us to, to build structures like we’ve never done them before. Every time we’ve flown, structures, at least the United States, we’ve built spacecraft end to end here on the Earth, we’ve tested them in a controlled environment, in a hangar, and had a chance to introduce failures to see how the systems respond. We could modify them as needed until they’re all ready to go. And then you have this, this whole piece that you’ve end to end tested, and now you launch it into space. When you build space station you can’t do it that way. We haven’t done it that way. We’ve had pieces and parts that have been added to space station. They’ve been contributed by countries half a world away, built by countries speaking other languages in some cases, built with different design philosophies. A lot of the Russian segment modules were built fundamentally in a different fashion and designed in a different fashion than the U.S., European, Japanese modules and the Canadian pieces as well. But we’ve been able to integrate all that stuff real-time on the fly here in low Earth orbit. That experience, I think, will stand us in good stead when we go to do the other kinds of things, going back to the moon. We’re not going to build the lunar habitat here on Earth and launch it intact to the, the moon’s surface, and certainly we’re not going do anything like that going to Mars. Going back to the moon, on the scale that we’re talking about, and going on to Mars, these are going to be international efforts. Learning how to build the space station in an international fashion, involving many different countries with different cultures, different languages, and potentially designing hardware with different philosophies -- that experience is going to apply directly to going on to the moon and on to Mars. So I think space station’s great legacy will be its contribution, helping us to do those kinds of things. I think everybody here is very excited about finishing the space station, but we’re also keeping an eye towards these next great, exciting missions, going back to the moon and on to Mars and beyond. I don’t know if I’ll have a chance to do some of those things, but I will certainly be watching in anxious anticipation as some of the folks who are already here at Johnson and elsewhere get a chance to do that. It’s an exciting time.