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Preflight Interview: Robert D. Cabana

A couple of weeks prior to scheduled launch, STS-88 commander Robert Cabana took some time out from training to answer questions about the mission.

Bob, it has been two years since you were named to the crew of STS-88; well, now you're closing in on the scheduled launch; what are your feelings as this flight really begins to approach reality?

I have an extremely excited crew that is very well trained, and we are anxious to go. I think you kind of postpone your, "getting ready" a little bit: you don't want to think that, "Hey, I got to really get into this and get psyched and get going" until you know it's going to happen. And within the last month we've reached that point-this is going to happen, the crew is really getting focused and psyched to go do this, and we're ready.

The target launch date has been postponed twice because of delays in getting station hardware prepared. Have the postponements been frustrating to you and your crewmates, or did it provide you an opportunity to get better prepared?

I think both is the answer. You always want to go fly, so it's disappointing when a launch slips out. But we've benefited tremendously from the launch slips, we've had a real opportunity to get down to the Cape, over to Russia, to see the hardware, to learn more about it, especially the computer software that's going to be used, on the space station. We've had a number of runs developing new software, making sure things work right, and it's made us a lot more knowledgeable. And it's made the community as a whole a lot more knowledgeable on what we have, in ensuring success when we get up there on orbit.

You have been working with a crew of four other folks, three veterans and one spaceflight rookie, for close to two years now. As the Commander, tell me how have you seen them all, and yourself, begin to grow together to work as a team?

I think we've grown together real well. It's interesting working with a crew that's very experienced as opposed to dealing with a crew that has not flown before. In one case, you've got to provide maybe a little more guidance or direction, or you're helping out a little bit more. But in this case, I know these folks are extremely talented, they know what they're doing, and so you got to step back a little bit and not get quite as involved - let them develop the issues and work them. And it's been a real pleasure to see their enthusiasm for the flight, for their jobs, and digging into it and making sure that everything works when we get up there.

Now after all of this time with the five of you folks working together as a group, you recently acquired another crewmate with the addition of Sergei Krikalev to this mission. How is this change, relatively late in the game from your point of view, going to have an impact on your preparations to fly?

Sergei adds a lot of experience to the crew. We could've accomplished the mission without him, but it's an extremely challenging mission from a time-scheduling point of view, and Sergei's going to provide expertise on the Zarya, the Russian Functional Cargo Block - with him it just makes it a little easier. He's also going to be backing us up on a lot of the other tasks that we have on the flight. He'll be helping with the Space Vision System; he's going to be doing a lot of Photo/TV work, documentation, helping there. With his EVA experience we're going to task him to be IV2 inside the vehicle during the EVAs, helping the crew get suited up, etc, and track everything along in those regards. So we've added a lot of tasks that he's going to be able to offload, whereas before, we had no spare time; and now we still don't have any spare time but at least we can get things done with a little more backup. In some cases we may have had somebody working on something without the benefit of having somebody with them, and now we have that advantage. So Sergei brings a lot of experience, but specifically, we've made him prime for the FGB and all its systems during the ingress.

From the point of view of symbolism, if nothing else, does it make sense to you to have a multinational crew on board the first mission to begin assembly of an international space station?

Without a doubt. I mean, we do have a piece of Russian hardware up there, that they built, that we paid for, that they're launching, and I think this is a stepping-stone to the future … an international cooperative effort. And so getting the first crew up there, having that cooperative effort show at that stage of the game, I think it adds something to the flight.

In your mind what's the historical significance of this flight? Why should we be building a space station in Earth orbit?

Well, the International Space Station, in spite of all the technical benefit that it's going to give us in Earth science, life science, exploring; I think the primary benefit is that it's a stepping-stone to the future, and the future of space exploration is all of us working together. Space exploration has become part too costly for any one nation to pursue on its own, and truly, we are one world as seen from space, and I think that when we explore beyond the confines of Earth's gravity, it should be at a multinational level. And we are learning through the International Space Station to cooperate on that level. When you consider the task that we have before us - we're bringing hardware from all over the world together and assembling it in space with people from all over the world. Different languages, different backgrounds, different customs, different ways of doing things … and making that all work; this is a tremendous opportunity that's extremely valuable to our future.

You're well aware there are people who question the value of the United States working with Russia or any of the other international partners in the space station. What's your response to that criticism?

My response, drawing on what I've just said, is that it's all our responsibility, space exploration … we have to learn how to get together. And, maybe if we can learn to work together in space we can get a along a little better here on Earth. But I think the true benefit is to draw from everybody's experience. Everybody has a little something to add to this space station, space exploration project. And I don't think we should overlook anybody's abilities or experience. So I think it's definitely the right thing to be doing. From a technical point of view, we could've done it alone; but it adds even more bringing not just the Russians, but the Canadians, the Japanese, the European Space Agency and all its partners. Everybody's got something to add, and I think this is a step toward even greater cooperation in the future.

From your point of view, what've been the most valuable lessons that have come out of the Shuttle/Mir effort?

Well, first off, we couldn't have done the International Space Station with the Russians as partners had we not done Shuttle/Mir. We have learned an awful lot, and not just technical stuff. We've learned to inter-react on a personal level with them - they have to get to know us and we have to get to know them in order to work together, and Phase 1 has provided that. Operationally, they do things different than we do, and we've learned how they operate and they've learned how we operate. And bringing thirty years of space experience on both sides of the ocean together has not been an easy task. Everybody naturally kind of thinks they have the right way of doing things, and I think learning how to operate together is extremely important. So, Phase 1 was crucial to the success of the International Space Station. The cooperation, getting to know the Russians on a personal level, and developing trust - you got to have trust before you can do anything, and I think they've learned, and we've learned, to hopefully trust one another.

STS-74, the second Shuttle/Mir docking mission, in which the shuttle crew used the robot arm to install a new Docking Module to the Mir space station. How important is that in setting the stage for your mission, in which your crew will use the robot arm to grapple the Unity node, put it in place in order to dock to the first piece of the space station?

Well, we learned from that flight … in some aspects there are similarities, but in other aspects they're greatly different. As far as actually taking Unity out of the payload bay and mating it with the orbiter docking station, it's very similar to STS-74; but from there on, that's were the similarities end. The difference is on STS-74, they had cameras mounted such that when they docked with the Mir space station they were looking directly through the other end of the docking adapter and were able to fly the orbiter precisely onto the mating surface of Mir. What we're doing, however, is we're going to rendezvous with Zarya up in space and actually fly it down into the payload bay behind the Node where we can't even see it out the windows. And then using television cameras and the arm, we're going to grab onto it and then position it over the top of the Node and mate the two pieces together. And again, we don't have a direct camera view to line everything up precisely; we're going to be relying on the Canadian Space Vision System, which uses photogrammetry to line up a bunch of dots. And by knowing where they are, using cameras, it can precisely align the two pieces together. And then we'll fire the orbiter jets, to cause a mating just like when we mate with Mir space station.

Tell me about the complexity of arranging the whole process, and then of executing a plan to put together a space station in space.

We've got an extremely complex and challenging task ahead of us for the next four years. We're doing more EVAs, spacewalks, than we've ever done before and every one of them is a challenge. Every piece that comes up requires precise mating to the space station, which is not always done with direct viewing. It relies on the Space Vision System, a series of new robot arms, and, so on. So we have a lot of new hardware coming up, and we're putting it together in ways that we haven't done before, and all of it involves challenging EVAs. And every one of the assembly missions is a little bit different than the one that preceded it or the one that follows it, so you can't really say that we're going to do it just like we did the previous one - each one presents a new challenge, a new training challenge, and new technical challenges. It's a lot of hardware going up, and the hardware's built, I've seen it. It's not just Unity and Zarya, I mean the rest of the pieces are built too, and they're stacking up down at the Cape getting ready to go. So once we get this thing going, there's no slowing down. And that's another key point when you look at the challenges … each part requires a certain other part to get up there within a certain time frame or you start running into problems. So once we start, we've got to maintain that schedule and get the pieces up there. It's certainly challenging, just from the complexity of it. Challenging in regards to the EVAs, and getting a lot of this hardware up there together in space for the first time and making sure that it all operates.

Let's talk about the first two pieces, the two with which you will be involved: the Zarya control module, which the Russians are launching, and the Unity node, which you are bringing up on orbit with you. Describe these two pieces of hardware and what their roles are in the operation of the station.

Sure. Zarya, the Functional Cargo Block, is essentially the initial module which provides propellant for thruster control, and electricity and environmental control systems for the initial stages of the space station. Unity, the node, is a connector piece that holds all the other pieces together. We're going to have the Z1 Truss mounted on it, which eventually all those solar arrays are going to go off of, as well as other structure. And it'll have the U.S. Laboratory hooked up to one end; it's going to have a cupola so that we can see outside. It's going to have the airlock hooked onto it, and eventually it'll have a TransHab Module hooked up. When I relate it to children I say "Remember Tinker Toys when you were a kid? The Russians are going to have one of those sticks up there, and we're going to take up one of those round pieces and hook the two together so that we can add on all the other pieces." So, it sounds simplistic but that's essentially what Unity is, and then it's got its own systems and storage inside. Of course, once the Service Module comes up, then the FGB ends up transferring a lot of the capability that it had, the functions that it was serving, over to the Service Module.

What sometimes is called the FGB, we've been calling Zarya, it's the same piece of hardware?

All the same.

One of the first highlights of this mission is going to be when you fly the rendezvous, Endeavour to Zarya, and set it up so Nancy Currie can use the shuttle's robot arm to grab that module. Take us on to the flight deck with you and talk us through that rendezvous timeline and what you're going to be doing that day.

Well, hopefully we're going to get a really good night's sleep the night before, because we want to be well rested and ready to go; we're going to get up early in the morning, and we've got a full day. We start our burns right away, to start the phasing so that we can join up with Zarya. Once we get in close, from our TI burn, we'll be one rev out and we'll come around on in, and we come in on the plus R-bar, down below. If Zarya's orbiting the Earth on the vector that points down to the center of the Earth, that's where we intercept and start driving on up to it. Then, when we get about 550 feet away from it, we're going to do a flyaround at twice the orbital rate. So if it takes ninety minutes to orbit the Earth, we'd be flying at a rate such that we'd orbit Zarya in forty-five minutes. So in 22-and-a-half minutes we'll be intercepting the minus R-bar, up at the top, and as we spiral around, we'll be getting a little closer. We'll start out at about 500 to 550 feet; when we're out in front of it we'll be at about 350 feet; and then we'll come in at the top at about 250 feet. And now it's getting pretty big, and we're watching it rotate around, now we're at the right end of it. The reason for this flyaround, and not just joining up with it from below, is so that we're not blocking Russian command to it, from the ground - the shuttle's not acting as a blockage there. So we'll come down from the top and, we'll fly it right down into the payload bay. We've got a camera in the keel of the orbiter, actually we have a prime and a backup, and we'll be able to center the FGB right in the field of view of the camera and fly it right down. And then when it's about, oh, thirty feet away or so, the end effector camera will pick up the grapple fixture in its field of view and we'll get everything nice and stable so that it's not moving. We'll go free drift on the orbiter's jets, and prior to bringing it down in there, the Russians, once it's all stable, they'll go free drift also. So when everything's nice and stable there, Nancy'll just reach over and grab it with the arm. And once we've got it captured, then we transition it up to the top for final mating.

So you've got Zarya on the end of the arm; now it has to be attached to the piece of hardware that you have brought with you, the Unity node. How does that work?

Nancy positions it with the arm over the other Pressurized Mating Adapter, and we have an APAS docking system just like we use when we dock with Mir. We'll position the two pieces so that they're approximately six inches apart, perfectly aligned in "X" and "Y" and in pitch, roll and yaw, so that it's straight above it, six inches apart, and then we fire our post-contact thrusters. Essentially we're going to use the orbiter jets just like when we dock with Mir - we'll have it all set up, we'll fire the jets, and the two pieces will come together and then the APAS will lock on to the extended ring. Once they're mated, then we'll draw the two pieces together until they pressurize, surfaces are together, and then we drive hooks to lock them together.

As you think through that entire process of that day's tasks, what are the most difficult parts of the job for you and for your crew?

Well, let's see … they're all difficult. We get used to making it look pretty easy; I hope it's that easy on orbit. I think probably one of the most challenging tasks is that we're flying Zarya down into the payload bay blind. From about a hundred feet on down, we can't see it because the Node blocks it out of the window, and we're strictly relying on the cameras to keep it all centered up. Positioning it over Unity, for berthing the two pieces together, again we don't have a really excellent camera view to ensure that everything is precisely aligned because it's so far above, where we're putting everything together, where we can see with the cameras. So ensuring that that's all precise before we fire those post-contact thrusters … we'd sure hate to see it bounce off because it wasn't aligned right. So, I think the final stages of the rendezvous, and the alignment, when we actually drive the two pieces together, I think they're probably the most two challenging parts of the timeline there.

Rendezvous with Zarya is going to be something of a first-you have a manned spacecraft that's being controlled from here in Houston, meeting up with an unmanned module that's being controlled from Moscow. Are there new levels of coordination or communication that are necessary to make this happen successfully?

Well, we have done similar tasks in the past, but I think the level of coordination is going to be extremely high; the folks on the ground are working very hard to ensure good communications between MCC Moscow and MCC Houston. There are a lot of calls back and forth to ensure that everybody has the right attitude control at the right time and that we get all our "go"s for capture and docking at the appropriate times. So I think the key is, we've set the groundwork during Phase 1 - getting to know those folks over in Moscow. Our control teams have a very good rapport, and I think that's going to help tremendously to ensure that we have that same level of communication when we do our task.

In the simulations, you say it seems to go pretty smoothly but, I presume that you've also trained for scenarios in which everything doesn't go exactly the way…

We've seen a lot of scenarios that we don't ever want to see again, especially on orbit.

Give me an idea of what the critical failure scenarios for this operation are, and how you've trained to respond to those should they happen.

Well, we've done a lot of training with malfunctions to the RMS, the robot arm on the space shuttle, various backup modes, if it doesn't work as it's supposed to work, how can we get around that? What backup modes can we use to still accomplish our task? And Nancy Currie, our prime arm operator, has just done a fantastic job pulling all those malfunctions together and ensuring success. We've spent an awful lot of time playing "what ifs" just in the office: what if this happens, how can we work around that? I think that's one of the benefits of having the schedule slips that we've had, we've had a lot of time to consider all the things that can possibly go wrong and try to have a plan in place to handle it should it happen on orbit. That's not to say we've thought of everything, but we sure have done our best. Loss of cameras greatly effects how we do our task: what backup views do we have, what other cameras can we use if we lose our prime cameras for the various tasks? We've looked at failure of the grapple fixture; should it fail what can we do? Are there other ways of getting around that? What if we have control problems of the FGB, what if it's not in the right attitude when we get up there? You know, can we get it stabilized with the backup means of control for Zarya and then do a fly-out of the missed attitude, and still come in and get it. So, yeah, a lot of time training for some really off-nominal situations that, again, I hope we don't ever see.

Once the two pieces are successfully joined, Jim Newman and Jerry Ross are going to conduct three spacewalks to complete the connections between the two modules. Tell us about your responsibilities inside the shuttle while they're working outside on the first two pieces of the new station.

Once we get the two pieces joined together and they're all attached to the shuttle, then our work really begins. We're not even halfway through the flight yet because we've got those three EVAs, and going inside, the activation to do. On the first day, during the first EVA, we will mate all of the electrical connectors and get some of the outfitting done. Once that's complete and we have power from Zarya to the Node, we can actually power-up the MDMs, multiplexer-demultiplexer - it's the computers on the Node, to actually activate the space station and its systems. And we'll be doing that from a portable computer system, talking through the aft flight deck of the space shuttle to the space station. So there's a point during that EVA when we get a "go" for activation, and I get to send the commands to actually power everything up, so we're kind of looking forward to that. We recently completed a full test of all of that down at the Kennedy Space Center a week ago and everything actually worked, so we want to see it work as well on orbit.

Once these two pieces are mated and after the second of the three spacewalks, you and your crew are going to be the first group of people who will actually go aboard the International Space Station; what're your feelings about being in that position?

Well, we're extremely excited, as you can well imagine, to get to do that. We'll have everything powered-up and then, we'll go inside and start outfitting. We've got a lot of hardware on the middeck of the space shuttle that we're going to transfer into the space station. And there's a lot of equipment on the space station, some panels and stuff, that provide structural support for launch that will no longer be needed, that we'll be able to take off and bring back home - so the crews don't have to deal with that on orbit. We'll also be installing an Early Communications system on the Unity, and it's a couple of antennas and boxes inside that Jerry Ross and I are going to hook up that will allow commanding and communication from MCC Houston directly to the space station. It will provide the crew on board, the first crew, to actually have video teleconference capability with Houston. Hopefully we'll get a chance to check that out while we're up there too.

Have you determined which one of you gets to go through the hatch and onto the station first?

Well, I think the Commander oughta be the first one on board.

First into Unity; is there any other discussion about who would be the first to go inside the other piece of the station?

Well, we're looking at it as one space station.

Give us some more detail about what you expect to see once you get inside Zarya and what you have to do to activate it?

Well, in all of the modules, what we're going to have to do first is open a series of hatches and ensure that the pressure and environment inside is safe. We're going to have supplemental oxygen masks available should there be a concern with outgassing of the various materials, not having a good environment until we get a chance to activate all the systems and purge the air, but we don't expect that to be a problem. So the real key is making sure that the temperature, pressure, and oxygen levels are correct. And then as we open the hatches, the middeck hatch will be open, and the airlock hatch, and the hatch to the orbiter docking station, and then there's the hatch on the PMA, and then there's the hatch between the PMA and the Node. And now we're inside Unity and there's the hatch between Unity and the other PMA, and then there's the hatch from the PMA to the first compartment of Zarya, and then there's the hatch between that compartment and the main compartment of Zarya. Plus you got to turn on all the lights as you're progressing on in through there because none of those lights were on when you initially went in. So it's going to take us pretty much a full afternoon from the time we start leaving the orbiter, transitioning inside the space station, to actually completing everything. Once we make sure everything's right, then we're ready for the transfer ops to start.

In terms of the whole sequence of assembling this space station, just how critical is any one step? Does the whole assembly sequence come to a halt if you don't do each and every little thing that is on the timeline for STS-88? Or is there some required threshold at each step that's required in order to facilitate the next step?

We have a minimum set of tasks that we have to accomplish, and then we have a large number of tasks that are get-aheads for future missions, so that they have a better chance of success on their flights. Our third EVA is not packed right now; if we have problems on either of the first two EVAs, we can offload some of those tasks to the third one in order to make up. So everything is planned out such that you want to accomplish the things that you absolutely have to get done, and then, hopefully, you'll have a little time to do some of these get-ahead tasks to help out down the road. So, yeah, if we don't get Unity and Zarya mated together with all their electrical connectors made, and the computer system up and running, then we've got a real problem for down the road. But if we accomplish that much of the mission, we're well on our way, and then we'll try and get ahead and help out on the future missions. But each flight in sequence, in space station building, pretty much has to be accomplished, maybe not in its entirety, but the major mission objectives have to be accomplished before you can proceed with the other missions.

So after the third spacewalk, and after you undock and leave behind the International Space Station, in your mind what will have had to have happened in order for STS-88 to have been a success at that point?

If we leave a working space station up there, with control and good communication between Moscow and Houston, and it's ready for the next piece of hardware to come up, it'll be a success in my mind. And that's pretty much doing everything that we have to do on our flight. I think it's going to be extremely rewarding - to see it up there, a stepping-stone to the future, to have been able to participate in that is going to be really special.

On your way home from the International Space Station you have got plans to deploy two more satellites before you get all the way home. Describe those payload for us, and discuss what's involved for you and your crew in deploying them.

Well, we have two satellites on board - MightySat, which is a Department of Defense payload, and SAC-A, which is a satellite that's being launched by the Argentinean Space Agency. They're carried in gas cans back in the orbiter payload bay, and essentially, you open the lid and they've got a spring propulsion type system that will deploy them at the appropriate time. We'll precisely maneuver the attitude of the orbiter to make it exactly right for what they want, and when everything's right we'll deploy their payloads. So Rick Sturckow, my Pilot, is the one that I've put in charge of ensuring that we're in the right attitude and everything is done for those. He's looking forward to deploying a couple of satellites on orbit.

From strictly a philosophical stand point, what is the meaning of the International Space Station for the future of space exploration, whether it's to go to the moon or to Mars or to anywhere? Why is this important?

Well when I said it's a stepping-stone to the future, I truly believe it is. I think that, us as one world, working together on an international space station, learning to live together, to work together, to share science, to share responsibilities, to really get to know one another, is preparing us for going beyond the confines of Earth's gravity. I think of the Hubble Deep Field picture, and here's this little space up there by the Big Dipper, the size of your fingernail, and you put it up there and you can't see anything. And they point Hubble at it and they see not only a lot of stars, they see galaxies. You know, for us to think that we're the only ones capable of intelligent thought in this infinite universe I think is not the right way to be thinking. And I think that it's in our destiny to explore and to go beyond our solar system, and further … and I think this is the beginning. And I think we're going to go back to the moon, we're going to go to Mars, and we're going to do it united. So from a philosophical point of view, I look at it as the beginning of us really working together, exploring. We always learn when we explore. And the really neat thing about exploring is it's always something new, and this is the beginning of that.

With all of that in mind then, since STS-88 starts this process, how would you like history to remember the mission that you are going to command?

As a crew, I'd like them to remember that they worked hard and that they did a good job, and they were successful. I'd really like to see this as a success. I think a lot of folks, throughout NASA, throughout the whole space agency, throughout all our participating partners, have been working extremely hard to bring this to fruition, and we are extremely proud and privileged to represent the end result of all that effort. I'd like to ensure that we don't let anybody down, and that we give their hardware and all their hard work the just recognition that it deserves; by making it all work together in space.

Image: Robert Cabana
Click on the image to hear Commander Cabana's greeting.
Crew Interviews


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