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Preflight Interview: Brian Duffy

The STS-92 Crew Interviews with Brian Duffy, Commander.

Q: Talking with Commander Brian Duffy of STS-92. First off, why did you want to be an astronaut? Was there any particular event or person that inspired you?

A. Well, the idea of being an astronaut was something that was planted when I was maybe in 3rd grade or so, about 8 years old. I was one of all those kids that sat in front of the black-and-white televisions and watched Alan Shepard launch. And you know, I thought a lot about you know…my imagination would run wild, just like any child's imagination does. And I thought how great it would be to be able to do that. Of course, I never dreamed, at the time, I'd ever have an opportunity to do it. So, I think the seed was planted very young. And it wasn't until actually I had finished Test Pilot School and was flying as a test pilot in the Air Force…the opportunity arose to be able to apply for the program here to fly space shuttles. And it was an opportunity I just couldn't pass up.

Well, tell me a little bit about how that opportunity came to pass. If you would, give me an overview of your education and career, and just tell me how you got here.

Getting here to this seat was as you know, of course it's been an interesting road in my career. I grew up in a small town south of Boston called Rockland, Massachusetts. And I went to high school there. I grew up and went to high school there, and not far from there, there was a naval air station. And South Weymouth Naval Air Station. And I always watched airplanes coming and going in and out of there, and I thought it would be an interesting you know, something I would like to do. It would be something that would be neat to go fly fighters like I saw coming in and out of that base. And I applied to the Air Force Academy for college and was accepted to go there. And while I was there at the Academy, I majored in mathematics, played baseball, and had a good time. But probably the most important thing I did was, I got a chance to fly in a number of different airplanes, one of them being the F-4. And to be a 19-year-old at the time in the back seat of an F-4, a hundred feet off the ground, going 600 miles an hour made me realize that was something I really wanted to do. So, graduating from the Air Force Academy led me to pilot training, and I wanted to fly fighters out of pilot training and was fortunate to do that. [I] got an F-15 assignment. I flew a couple of assignments in the F-15, and I had the opportunity to go to Edwards to go to test pilot school. I went to do that, and I was flying F-15 flight tests at Eglin Air Force Base up in the panhandle of Florida when, back in 1985, when a call for applications went out and they were looking for people to apply for the shuttle. And I was surprised to find out, quite frankly, that I had qualified and filled all of the squares that you needed to fill to be competitive to apply. And I thought, you know, I couldn't let that 8-year-old kid from so many years ago down to find out that I was qualified to apply and not do it. You know, would I be able to live with myself? So, I applied and I'm very, very fortunate to be here.

All right. This flight begins a series of missions involving the largest and most critical hardware for the International Space Station. If you would, discuss this flight's pivotal role in the assembly sequence and why this flight is crucial to enabling the rest of the missions to follow in sequence.

Well, you know, the truth is, every single mission in the sequence of building the space station is equally important. And regardless of what you have in the payload bay-whether you're bringing up hardware, as we are, or if you're bringing up crewmembers or if you're bringing up supplies or you're bringing back things- all of those missions are required. We're in a stretch here where we do, in fact, need a series of serial successes, where every mission has to work because the follow-on missions depend on you getting your things done. And that fact hasn't been lost on my crew nor on all of the other crews that are assigned and training right now. So, we understand the importance of this. Is our flight important? Sure, it is. But it's no more important than the other flights. We'll be bringing up the Z1 Truss, which is an important piece of the space station structure and also adding Pressurized Mating Adapter-3, or PMA-3 to one of the ports of the Node. And the reason that's important is because on the flight that's going to follow us, he needs that port, that PMA to be there so he can dock to it because he's not going to dock to the port that we dock to. So, that's just an example of how interrelated these flights are and how important one is to the next.

What are and what have been the biggest challenges for you and your crewmates as you trained for this particular flight?

Well, we've had some challenges. We've been training for quite a while now for this. And, one of the challenges you might equate to training for a race or something or running a marathon, for example, you know, this has been a long process. And we need to…didn't want to peak too soon. We wanted to, but we wanted to make sure that we were adequately prepared and ready to go when the time came. So, pacing ourselves has been important. The time that we've had to train, however, has been put to good use in that we've not only been involved in getting ready, getting ready and training for the things that we're going to do, but we actually had a chance to get involved in putting the flight together and planning how things were going to get done and who was going to do them. And, so that's been something that we've taken advantage of here in the last couple of years while we're getting ready for this mission.

Now after you rendezvous and dock with the ISS, your number one priority is the installation of the Z1 Truss that you mentioned earlier. Describe for me the Z1 Truss in some detail. How big is it, and what does it do for the International Space Station now and in the years to come?

Well, let's see, describing the Z1 Truss. It's not a big, sexy piece of hardware. It's about a…I would estimate, maybe a 15-foot cube. And it's 18,000 pounds or so. It's going to be in the payload bay. It's important because it becomes the base that all the solar platforms are built on. We put it on the zenith port of the Node. The top port of the Node. And we'll have it there. And then the follow-on flight, 4A, with Brent Jett and his crew, they will add the solar array on top of that. So, this is an important base. It also has a lot of other important equipment in it. It has the Control Moment Gyros, for example, that will be used for controlling attitude-the attitude of the space station-so they can be in the attitude that they want and point the solar arrays at the Sun for electrical power generation. It also has the S-band and Ku-band and communications antennas on board. It has a Plasma Contactor Unit on board. It has DC-to-DC converter units on board. It's a very well-designed, very compact piece of structure. And what we're going to be doing on the flight, if you can think of it as your trunk when you're going off on vacation is, if you packed your trunk for vacation, you pack it very strategically. You don't waste a cubic inch. Well, that's the way the Z1's put together right now. We're going to carry it to orbit, dock with the station. Koichi Wakata will use the robot arm and place it in position. Pam Melroy will be operating the Common Berthing Mechanism, which will be the first time that'll have been done on orbit. That'll attach the Z1 Truss on to the Node itself on to the space station. And then on the following days-4 consecutive days- Leroy Chiao and Bill McArthur, Jeff Wisoff and Mike Lopez-Alegria will go out in two teams of two and they will unpack the trunk. It's the equivalent of getting to your destination and now taking all of those things that you'd put in every nook and cranny and putting it in the place where you're going to need to have it, not so much for a vacation I guess, but where we're going to need to have it so that we can use it.

What are some of the difficulties and complexities you've trained for in this whole installation process?

Well, this flight is pretty complex from start to finish. And that's because, you know, we're bringing, we have hardware that's on the space shuttle program side. We have hardware that's on the space station program side. Then we have international involvement as well with the having the Russians involved. And so, pulling all this together, into a nice, neat little package has been a real challenge. All of the details. The big things, you know, when you talk about it in large terms, you say, "Well, we're going to launch a space shuttle. We're going to carry space station hardware. And we're going to dock over a Russian ground site and do some other things over a Russian ground site so that they can do commanding powering things on and off." That sounds pretty easy. You know, the devil's always in the details. And the details have been the challenge for us.

Now you mentioned this in passing a few moments ago, but what additional communications will be possible after you do install the Z1 Truss?

Well, actually, once we get the Truss on board, the space station will still be in the same configuration for communications as far as Bill Shepherd is concerned on the follow-on, the folks that come on up. We will have it on board, but there'll be some future additions that'll be required. More hardware brought up, more software brought up to fully enable and get the entire capability of the hardware that we're bringing up there.

And once that hardware is installed, what will it be capable of communicating?

…the communication systems that are on board the Z1 Truss are going to be the heart of the comm system for the whole space station. And…they'll be able to send down both high and low data rates so that all the data that's associated with the experiments-all the voice communications, all of the video that will be sent down-that'll all flow through those systems.

All right. Now what are the Control Moment Gyros, and what do they do?

Well, the Control Moment Gyros are these massive rotating structures that are in the Z1 itself. And what they do is, they use torque to…they act as gyroscopes; and we use the precision that you get and the torque that you can generate from spinning a mass to point the space station where we want. And when we fly the space shuttle, we use Reaction Control System jets. We use thrusters in order to point that. And when you're using a thruster, the thruster produces thrust by combining a fuel and an oxidizer to produce the force. Well, that's a consumable. So, every time you want to make a change or point at something, you're using consumable. You're using propellant. And with the space station and maneuvering it all the time, we almost, I don't think we could carry enough propellant to orbit to keep doing it forever. So, these Control Moment Gyros we can use to point the space station where we want it without using propellant, if you will. We still have a propellant system as a backup but the CMGs will be the primary means of pointing the station.

Okay. Tell me more about the DC-to-DC Converter Units. What do they do?

Well…there are many DC-to-DC Converter Units on the stations. The ones that we're [carrying] up will be ones that'll be mounted on the Z1 Truss. And they're going to help condition the electrical power that's generated by the solar panels that are going to come up on the mission after us. [They] generate, or condition that power that's generated so that it can be used by the space station itself.

Okay. Now I understand the Z1 Truss can help eliminate static discharges on the station. Tell me about this. Why is this important?

Now, well, you know, I'm not a scientist in doing this. But…static electricity is generated whenever items come in contact with each other and then are separated. So, as the space station flies through space it still encounters atmospheric molecules. You know, there's hydrogen and nitrogen and oxygen molecules that are up there. So, over time and with the size of the space station, it'll generate a lot of static charge. And the Plasma Contactor Units are ways in which the change can be neutralized.

And now what role does the Z1 Truss play in controlling the temperature on board the ISS?

Well, the Z1 Truss has some ammonia in lines there. And it's not an active part in, necessarily, in the thermal control of the ISS. But it'll enable the entire cooling system. It'll be a part of the whole cooling system once it's put together.

Okay. This flight features four space walks. And during the first one, the S-band Antenna Support Assembly will be relocated. What is the S-band Antenna Support Assembly and why are you moving it?

The S-band Antenna Support Assembly - remember I mentioned that the Z1 Truss was put together as, the same way that you pack your trunk for a vacation. And it's located in a place on the Z1 Truss where it can withstand all of the launch loads and landing loads, should that be required. But it's not where you want to have it to use the S-band system. So what we'll do is Leroy and Bill will take that off of its stowed location and just relocate it over to where it's going to be in place when we use it.

Okay. Now also earlier, you mentioned the Pressurized Mating Adapters, and you're adding another one during the second EVA. What does Pressurized Mating Adapter-3 do and where is it located?

Okay. The PMA-3 is going to be located, it's going to be in our payload bay for, to start about mid-bay. And on that Flight Day Koichi Wakata will use the robot arm and he'll go over and he'll grapple it. And Jeff Wisoff and Mike [Lopez-Alegria] will be out in the payload bay at that time. They will loosen the 16 bolts that hold it to the structure that we carry it up on. Once it's free, Koichi will pick it up out of the bay and move it around over the nose of the space shuttle and attach it kind of on, around the front of the space station as we're looking at it. It's really going to be on the bottom of the space station when it's free-flying.

All right. There are four space walks on this flight. What are your responsibilities during the space walks? What will you be doing?

Well, the space walks, of course, I can't necessarily help the guys outside. But truth be known, they don't need help. They're very talented and they're very well trained. They're ready to go. My jobs on the inside are making sure that everything is in place to get them safely out the door and also, during the course of the mission, to monitor what they're doing and communicate with the ground to make any decision, any real-time decisions that we have to make to changes in plans. And then, once they're back in, to help get them out of their suits and get them fed and get them ready to go, you know, on their next EVA.

All right. If you would discuss the Common Berthing Mechanism and compare its differences with other docking mechanisms that we're more familiar with.

Okay. The Common Berthing Mechanism is a fairly complex piece of equipment that we will be controlling from inside the space shuttle. And it is in orbit already; the active part of it is already in orbit. And what it is, is it's four mechanisms spaced equally every 90 degrees around a ring. There are latches that we can command open, you know, into an open position. And then we can move the piece that we want to attach into place, and then we can command those latches to come up and grab it and to pull it down together. And then, once it's down, there are 16 bolts that are motorized bolts, motor-driven bolts, that we can also command using a laptop computer. And those bolts are what will generate the force that'll seal the two units together. And then we can do a leak check on them and make sure that they're working properly. Pam Melroy has become the expert on the CBM. And she'll be the first one to operate the CBM on orbit, the Common Berthing Mechanism.

Any particular issues with the CBM that you're concerned about at this point?

No. Actually, the CBM is very complicated. But it's very robust, also. And you can have multiple failures and the system will still work fine. To date, we've had a couple of very small glitches; nothing that would have been a showstopper on orbit. And we don't expect that there'll be any problem. We might have a, you know, something that we stop and talk to the ground about. But my expectations are that it'll work just fine.

Great. Now after the space walks are all complete, you're ingressing into the ISS. What are you doing inside the International Space Station? And will you be entering the Zvezda Service Module? And if not, why not?

Well, we do have quite a bit of work to do. We'll have two opportunities during the course of the mission-on Flight Day 4 and on Flight Day 9-to do ingresses. On Flight Day 4 it's going to be a big day for us actually. In the morning is when we're going to put the Z1 on and do the first CBM operations. And then after that is completed, which we think will be maybe around lunchtime or so, then we'll start the ingress into the Node and into the Russian segment as well; into the FGB. And once we're inside the Node and into the space station Jeff Wisoff and Pam are going to, they're going to start by opening up the hatch to where the Z1 was attached on the top. And they need to get access in, on the inside now where these pieces were pulled together, because we need to put a, connect a grounding strap across the interface just to keep the station electrically grounded, properly grounded. And they're also going to remove the four components that were used in the Common Berthing Mechanism in attaching them, because the Z1, once it's in place, was never planned to be moved. So, there's no point in leaving that hardware there. So, they're going to then take that hardware out, and that'll take them a few hours, probably, to do all of that. And in the meantime, we'll be ingressing toward…into the Russian station. While they're doing their work, we'll continue into the Russian segment, into the FGB. And in there, we're going to start preparing, or continue preparing, the FGB for the first crew that's going to come up, which is going to happen after our flight, shortly after our flight. And so, we're going to go in and change out a Harmful Contaminant Filter and you know, just precautionary kinds of things. Just making sure that everything is as pristine as possible for when Bill Shepherd and his crew get there.

You're docking to the ISS with two Russian Progresses attached. Describe the processes and challenges of rendezvous and docking on this flight.

Yeah. Rendezvous is something I'm really looking forward to. I had the opportunity to do a couple of rendezvous in my last flight. And in my flight before that, I was the Pilot on a mission where we did a rendezvous. So they're, for a Pilot you know, they're one of the highlights of the mission-just as for the Mission Specialists, the EVAs are the highlights for their flight. What we'll do is, we're going to come in and, come in from underneath, from, actually from behind and then up from underneath. And we're going to get to about, about 600, between 600 and 500 feet from the space station, and then we're going to just fly around in front of it. So, if it's here, actually, if it's like this, we're actually going to fly around in front of it and get above it. And then we're going to come down from above and we're going to dock from above it as we come down. Now some of the factors that make it…you know, a challenge are: we want to maintain the proper range and range rate, because timing is very important. The reason the timing's important is because, now, we want to be docking with the station, while we're over a Russian ground site. So, we have a limited window and a window open and a window closed time that we want to be docking within. So, staying on the profile and being in the right place at the right time, and with everything ready to go will be, you know, a bit of a challenge. That's what we watch as we do it. The flying part is something I'm really anticipating and I can't wait to do.

All right. Now tell me about the process of undocking for this flight.

Undocking is a little bit simpler than the docking process. The timing's still important in that we're going to undock over a ground site, also. And the reason that we're doing that, I failed to mention that before, the reason we're doing it over a Russian ground site is so that they have a backup way of commanding the attitude control system of the space station. We're going to be the last crew to leave the space station with it unmanned. After our flight when Bill Shepherd and his crew get up there, there'll always be a crew on board. So we'll be the last ones to leave it. If there were a crew on board, they could go to a computer and command the attitude control system of the space station to become active again. When…the two vehicles separate, we're in free-drift. Neither vehicle is trying to control attitude. We just want to separate with very low rates. But then once we're separated, we want to go back into attitude control. The station does because they want to point for electrical, to point the solar arrays for electrical power at the, you know, point them at the Sun. And we…want to ensure a nice separation as well. If there's no one on board, they can't command that backup, then there could be a problem. So, we do have a backup system using the Russian comm passes to do that. So, we just time everything so that, both for docking and for undocking, we are over Russian ground sites for backup commanding just in case we needed it. Once we separate on the undocking, we'll fly out. And Pam will be flying the separation. We'll fly out to, in the 400-foot range, stabilize, and then we'll depending on how much fuel we have, we'll either be able to do a fly-around or we'll just separate away, and then start preparing for…you know, the entry and the landing.

You worked with Leroy Chiao and Koichi Wakata on STS-72. Did that experience make your job as Commander any easier this time?

Well, I have to tell you: this is one incredible crew that I've had the pleasure of training with for the last couple of years. They all have tremendous talents, their great strengths. And knowing Koichi and Leroy as well as I do from our last training flow-and I also, the flight before that, I flew with Jeff Wisoff-so, knowing half my crew as if they're my brothers already certainly makes it a lot easier. When you're training together for this long and you're this close together, you become like a family. You become very close. And I'm actually not looking forward to the day when I don't get to see them all every day.

All right. Our Russian partners have shown a lot of perseverance in getting us to this point in the assembly. What do you think of their contribution so far and what does our partnership entail from this point on with future critical flights?

Well, working with the Russians has taught us a lot of things. They've taught us that there's more than one way to skin a cat. And they certainly do have perseverance. They've had some difficult financial times over there. Difficult, and that makes it difficult for them to do their job. They know how to do their job. They've proven they know how to do their job time and again. They're very successful. And it's, you know, once they get over their financial difficulties, things will get easier for them. Even as it is, though they are able to do the things that we need them to do; and we've been very happy with working with them and look forward to a great future working with them.

Now you touched on this a little bit earlier. But, if you would give me an overview of the role of this flight in preparing the International Space Station for the arrival of the Expedition 1 crew.

Well, we are the…our flight is going to be important in that we are, you know, another step along the way in building the space station. And by bringing the Z1 up and bringing the Pressurized Mating Adapter up, we've added a lot of capability to the station. But Bill Shepherd could probably go up there and do just fine, you know, without it. And if you asked him, he'd probably say he's ready to go before us. I don't really feel like there's a hard requirement for us to have to go beforehand. But we will have just added increased capability to the station before he gets there.

Now, tell me, what is the importance of establishing the space station and what do you believe it will lead to in the years to come?

Well, the space station is just our first step. You know, it's an opportunity for us to build a laboratory that is open 24-hours-a-day, 365-days-a-year, and in an environment that you can't re-create on the ground. And I would like to think that we don't know what we don't know right now. There's so much we're going to learn so much that we haven't even thought about, haven't even considered at this point that makes this whole effort worthwhile. In addition to that while we're doing it, we're bringing an awful lot of countries and peoples together in a common cause down here on the planet. So, you could think of it almost as a joint…or dual-goals program. And something that I expect great things from.

Yours is also the 100th shuttle flight. And, if you would, discuss the significance of the space shuttle in human spaceflight history, its uniqueness, its accomplishments, and its role in the future.

The 100th space shuttle flight. Wow! I never thought I'd be on the 100th space shuttle flight. But to us, it's just a number. It could've been, you know, flights before, you know, a flight in front of us, a flight after us. So, we're honored to be in that spot. The space shuttle is what's important in this whole process. And that's what you have to understand: this is the most incredible flying machine ever built. It roars into space you know, like a launch vehicle, a rocket. You can turn it into whatever you want it to do on orbit. It can carry cargo. It can be a laboratory. You can rendezvous with other spacecraft, as we're going to do, and dock with it. And then it reenters like a, you know, like a fireball and lands on a runway with a big 100-ton glider. It is an absolutely incredible vehicle that allows, you know, allows us to…carry equipment to learn more about the altitudes where we're flying. And we can learn more about aerodynamics and hypersonic flight. We can learn about human physiology on orbit by extending stays up to a couple of weeks. I think 17 days or so is the longest space shuttle flight we've had. And we've learned a lot about how humans behave and how the body reacts to zero-gravity for extended durations. We're about to learn a lot more on the space station when we spend a lot, you know, constant time, many, many months for individuals on the station. But it's the shuttle that has made that all possible. We wouldn't have a space station if it weren't for the space shuttle. So it was our first step in getting us to the station. And it'll be our, you know, our ride up and down and our lifeblood, I think, for the station for as long as we can see.

Image: Brian Duffy
Click on the image to hear Commander Brian Duffy's greeting.
Crew Interviews

Curator: Kim Dismukes | Responsible NASA Official: John Ira Petty | Updated: 04/07/2002
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