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Preflight Interview: Koichi Wakata

The STS-92 Crew Interviews with Koichi Wakata, Mission Specialist.

Q: We are talking with Koichi Wakata, Mission Specialist for STS-92. First off, if you would, tell me why did you want to be an astronaut? Was there any particular event or person that inspired you?

A: I remember that I started to have a strong longing for going to space when I saw the Apollo lunar landing when I was at 5 years old. And although at the time it seemed to me that only the people in the US and also former Soviet Union could work in space. And it seemed to me that to go into space was something like beyond reach for me as a Japanese, since we did not have human space program at the time. So for me, being Japanese going to space was something like an impossible dream to achieve. And now 30 years later I'm very happy. I'm very fortunate to be a part of the team here, to participate in the human space program.

Well, if you would, give me an overview of your career that led you to this point. Tell me how you got here.

I was very much interested in aircraft since my childhood. I really enjoyed making engine-powered model planes and flying them. I also was in a team of…at the college participating in competitions of building and flying human or piloted gliders. And that's why I wanted to study aeronautical engineering. And I study that subject as an undergraduate and a graduate in Japan. After graduation, I worked for Japan Airlines as [an] aeronautical structural engineer before I became an astronaut. And in 1991, the Japanese space agency- National Space Development Agency of Japan-announced that they, that they will select a couple of astronauts to participate in the NASA astronaut training here at Johnson Space Center and also to eventually fly in the assembly flights for the Japanese module on the International Space Station. And fortunately, I was selected. I applied for the selection, and fortunately I was selected in 1992. And I came here, to Houston, to join the NASA astronaut class of 1992. And my first space flight was in 1996 on STS-72. And I had the opportunity to be part of the team and operate the space shuttle's robotic arm to retrieve the Japanese satellite launched by a Japanese rocket. And also I had an opportunity to operate the robotic arm for a NASA satellite called OAST-flyer satellite. And I have been working on this flight-STS-92-since the summer of '97.

Well, let's talk about this flight a little bit. It begins a series of missions involving some of the largest and most critical hardware for the International Space Station. Tell me about the pivotal role of this flight in the whole assembly sequence and what goes on just after you guys are up there.

Okay. Our flight will assemble two big components to the International Space Station. The first one is the Z1 Truss, and the other one is the Pressurized Mating Adapter-3 or PMA-3. First the Z1 Truss: that truss structure is going to be attached to the Unity module on our flight. And that Z1 Truss will house solar arrays which will be assembled on the following flight right after [our] flight. And Z1 Truss has [an] attitude control system-what is called a Control Moment Gyro-and S-band and Ku-band communication systems as well as thermal control system and Plasma Contactor Unit that controls a voltage between the space plasma and the ISS structure. So the Z1 has a lot of equipment on board. That's the first module that we put together on our flight after we dock to the space station. And following that we have Pressurized Mating 3, Mating Adapter-3 installation to the nadir side of the International Space Station's Unity module. And PMA-3 is a docking port for the space shuttle to dock to the International Space Station. And we need that PMA-3 docking port on the Unity module so that the following flights-STS-97 and -98- can dock to the PMA-3 to continue the assembly of International Space Station. So to continue the assembly flight Z1 installation and PMA-3 are essential.

Now, what would you say have been the biggest challenges for you and your crewmates so far in getting ready for this flight?

Yeah, this flight is a very challenging flight. And for example we have 4 days of back-to-back space walks, which will be the first time as a space station assembly flight. That will represent the challenge that our crew [will] face. And also for Z1 Truss and also PMA-3 those components are attached to the International Space Station by a mechanism called Common Berthing Mechanism. Our flight will be the first time to use the Common Berthing Mechanism to actually install components to the space station. So whenever we operate a certain system in space for the first time, we usually find something new. And sometimes it's, it could be a surprise. So we have been putting a lot of thoughts to make sure that this first operation of the Common Berthing Mechanism will be successful. So to prepare for this first-time event we have been spending a lot of time in going through a thorough training and testing.

So, what is the Common Berthing Mechanism? How does it work?

Common Berthing Mechanism is a mechanism that will be used in many places on the International Space Station. For example, the Japanese Experiment Module, called Kibo, will be attached to Node 2 in the future in the space station. And it has, we have various attachment system or docking system on the space station. For example when the shuttle docks to the space station we are using, we will be using a mechanism called APAS -Androgynous Peripheral Attachment System. And we have several other attachment [systems]. But the CBM provides us a big area-pressurized area-as a connecting mechanism so that we can transfer large payloads such as International Space Station standard payload racks and et cetera. So for this flight we will be connecting the Z1 Truss and the PMA-3 to both the zenith and the nadir side of the Unity module on the CBM, on the CBM mechanism.

So, why is the Z1 Truss the first external framework for the station? Can you compare the truss to anything that we have here on Earth?

Z1 Truss houses a lot of very important equipment for the space station. For example, attitude control system; communication for commanding and data and voice data as well; thermal control; and controlling the voltage. So I think a good analogy for the Z1 may be the entertainment, an entertainment center in the home that houses a lot of audio and video equipment such as TV, VCR, DVD, and radios and a CD player. And of course, the Z1 is there for the space station not so much for entertainment. But since Z1 houses so many important equipment for the space station, you can consider [it] as [an] entertainment center for a house.

Now, what exactly is the process of installing the Z1 Truss? How does that happen?

Z1 installation: it will happen after we dock on the Flight Day 3. And the current plan for us is to do the Z1 installation on Flight Day 4. First I will operate a robotic arm to grapple the Z1 which will be at the aft end of the cargo bay. And I will unberth or take out the Z1 from the cargo bay. First thing that I will do is to turn the Z1 Truss for about 25, 30 degrees so that the seal or the surface that will be attached to the Unity module will be seen from the camera that is located at the end of the cargo bay. This is so we can check the condition of the seal before we install Common Berthing Mechanism or the Z1 to the Unity module. After the inspection is complete, I will continue to move the Z1 to a position called a high hover position, which is over the left wing of the space shuttle. And at the point, our Mission Specialist Bill McArthur will operate the Space Vision System. Space Vision System is a system to provide the arm, RMS operators with very precise positioning cue of the payload. And he will operate a Space Vision System to calculate the vectors from the cameras on the aft end of the cargo bay to the Unity module. And after he operated the Space Vision System to get those vectors, those vectors will be stored in its memory of the Space Vision System. And after that, I will move the Z1 Truss very close to the Unity module, which is about 2 feet away from the connecting points. And at the point from the camera located at the end of the cargo bay, Bill McArthur will again use the Space Vision System to calculate the vectors from the camera to the Z1 this time. Now, we have vectors from the camera to the Node and also from the camera to the Z1. By using those two vectors, now the Space Vision System will calculate the relative position between the Z1 and the Unity module. That's the information that I use to operate the robotic arm. Because we do not have a very good direct view through the window or from any camera views, I cannot see the connecting point of the Z1 and the Unity module very well. So I have to depend on the precision, precise data of the position provided by the Space Vision System. So, using that relative factor, I use, I move the robotic arm to install the Z1 to the Unity module. And at about the 4 inches out between the connecting points Pilot Pamela Melroy will operate the Common Berthing Mechanism. And she send, she will send a command to…capture the Z1 using the latches of the Common Berthing Mechanism. And then I will put the robotic arm to link mode so that the second-stage capture of the latches will not be intervened by the force exerted by the robot arm. So, after the latch operations are complete, Pam will continue to send a series of commands to the 16 bolts of the Common Berthing Mechanism so that the Z1 will be securely fastened to the Unity module for pressurization. And that's the end of the Z1 install.

Now, once the Z1 is in there, what kind of additional communications are going to be possible with the International Space Station?

Okay. On the Z1 Truss there are elements of communication systems - some elements of the S-band communication system and also a Ku-band communication systems. And those systems will be enabled when the computer to control the systems will be available on the following flight. So we will bring up some components and also the antennas for the communication systems, but those communication systems themselves will not be available until later.

You also mentioned earlier the Control Moment Gyros. What are they, and what do they do?

Control Moment Gyros [are] used to control the attitude of the space station by using the principle of a gyroscope effect. There are four Control…Moment Gyros on the Z1 Truss. And that will enable the space station to precisely control the attitude of the space station without using the reaction control jets.

So, tell me - what are your responsibilities during the first space walk?

Okay. After the Z1 Truss was installed, the next day we have the first day of the 4 days of space walks. And that day Leroy Chiao and Bill McArthur will be performing EVA tasks. And I will be operating the shuttle's robotic arm with Bill McArthur at the tip of the robot arm to support his activities. On that day Bill McArthur and Leroy will connect the umbilicals between the Node and the Z1 Truss. And also they will be installing the Ku-band antenna and deploying that antenna boom using EVA and the robotic arm. So to support those activities, I will move Bill McArthur to the various convenient locations for him to perform their EVA tasks.

We've mentioned Pressurized Mating Adapter-3 a little bit. Tell me what that is. What does it do?

Pressurized Mating Adapter-3 is a docking port for the orbiter to dock with International Space Station. Very similar components are already on the International Space Station: PMA-1, which connects the Unity module and the Zarya module; and also PMA-2, which is now located on the forward end of the Unity module. Actually, we will dock to the PMA-2 on our flight. And on STS-92, we will be installing the PMA-3 to the nadir side of the Unity module so that the follow-on flights-STS-97 and -98- can dock to the PMA-3 to assemble the components to the International Space Station. PMA-3 has a weight of approximately 2,600 pounds and it has a canted cone-like shape. And the diameter of, on the larger side is approximately 9 feet. And that will be when we launch the PMA-3, it will be installed on the cargo bay on the SPACEHAB pallet with 16 bolts.

So, what happens to PMA-2?

PMA-2, after our flight will be relocated. The PMA-2 will be relocated temporarily to Z1 on flight STS-98. STS-98 will install the US Laboratory module to the forward end of the Unity module. Currently, the PMA-2 is located on the forward end of the Unity module. So, to install the US Laboratory module, PMA-2 needs to be relocated. So, on the flight STS-98, PMA-2 will be temporarily located on, relocated on the Z1; and after the US Lab module is installed on the forward side of the Unity module, PMA-2 will be again relocated to the forward side of the US Laboratory module. So PMA-2 and -3 will be relocated as we put, or as we add more modules to the International Space Station.

Okay. What will you be doing during the second EVA?

Okay. During the second EVA first task for me on that day, using the shuttle's robotic arm, is to install the Pressurized Mating Adapter-3. That will be launched in the middle section of the cargo bay. And that will be attached to the structure with 16 bolts and 4 latches. And…two EVA crewmembers- Jeff Wisoff and Mike Lopez-Alegria-they will manually unlatch and unbolt all of the 16 bolts and I will take the PMA-3 out of the cargo bay and maneuver it all the way to the nadir side of the Unity module. And at that time, again in a very similar manner as we did for the Z1 we need to use the Space Vision System as a very precise positioning aid for the RMS operator. Bill McArthur will be again operating the Space Vision System to calculate the relative position between the Unity module and the incoming PMA-3. And using that information, I install the PMA-3 to the Unity module. And at this time different from Z1 installation, we have two EVA crewmembers- Jeff and Mike- monitoring the installation of the PMA-3 just sitting right next to the Common Berthing Mechanism on the Unity module. So I have a Space Vision System to provide me with a very accurate positioning, and also we have very good four eyes of the space walkers to tell me exactly where the PMA-3 is with respect to the Unity module. So that installation will be a little bit easier in terms of finding a good position for installation. And after that PMA-3 installation is complete, then we will connect, the two EVA crewmembers will connect the umbilicals between the Node and PMA-3. So, again, I will this time put Jeff Wisoff at the tip of the robot arm to position him in a very convenient position for him to install the umbilicals for the PMA-3. And I will spend probably 3 hours supporting the space walk on that day on the EVA 2.

Okay. Now, tell me about the work you'll be doing during the third space walk. How will you be supporting that?

Okay. Third EVA again Leroy Chiao and Bill McArthur will be performing the EVA task. And in a very similar manner as I did on EVA 1 and 2, I will be operating the shuttle's robot arm to support their EVA tasks. Examples of the EVA tasks on that day is to install DC-to-DC Converter Units and also the space station toolbox for EVA. They will be relocating the toolbox, toolboxes from the shuttle's cargo bay to the International Space Station side. So, I will be moving the robot arm between the cargo bay and the International Space Station to help Leroy to conduct his space walk.

What is the DC-to-DC Converter Unit you mentioned? What does it do?

DC-to-DC Converter Unit is used to…convert voltage of the electrical system on the space station. The DC-to-DC Converter Unit converts voltage from what we call primary power, which is between a voltage of 115 to 170 volts, to the secondary power level, which is one [between]…123 to 126 volts. And that will be used after the solar array panel launched on the following flight, STS-97, comes on line. We need the P6 Truss, which houses that solar array. And after that solar array's launched, DDCU will function to convert the voltage for the space station.

There's a fourth space walk.


And once again you're supporting that. What work do you do to support that?

Okay. On the fourth day of EVA, I will also be operating the shuttle's robotic arm together with Bill McArthur. Bill McArthur and I will be operating the space shuttle's robotic arm to help the space walkers Jeff and Mike. First part of EVA 4 Bill will be controlling the robotic arm and I will be operating the robotic arm in the latter half of the day. And that day Mike Lopez-Alegria will be at the tip of the robot arm to perform several tasks such as relocating grapple fixture of the Z1. I use the grapple fixture to grapple the Z1 when we move the Z1 out of the cargo bay and install to the Unity module. And for following flights that grapple fixture needs to be relocated. So, Mike will move the grapple fixture and stow it inside Z1 Truss. And he will also be moving the foot restraints for following flights for space walkers. And after these tasks are complete, Jeff and Mike will start Detailed Test Objectives of space walk. And they will be doing two kinds of tests during this last day of EVA. One is a test of SAFER - Simplified Aid For EVA Rescue. That is the backpack that has nitrogen gas jets. In case EVA crewmembers are separated from the International Space Station they have a capability to come back on their own to the space station. And the test that they are doing is they will evaluate the performance and the handling quality of the SAFER. Both Jeff and Mike will be doing a series of tests. And one of the most spectacular [views] that I can imagine during the test is that both Jeff and Mike will take [turns] and they will fly from about the Z1 area, nearby the Zarya module. And I will be putting first Mike at the tip of the robot arm with Jeff about 5 feet out. Jeff will fly towards the camera on the backside of the cargo bay. So, it will be a pretty long free flight. And during that free-flight testing, I will be chasing Jeff using the robot arm, with Mike at the tip of the robot arm. And they take [turns]. And this time Mike will be performing the free-flight testing while Jeff is going to be on the arm while I maneuver to chase Mike as he approaches all the way to the aft end of the space shuttle cargo bay. So, after that both of the crewmembers will be doing the tests for a simulated incapacitated crewmembers in EVA. That's a rescue operation-type testing for space walkers. And I will put the arm to a place between the Z1 and the cargo bay's space pallet area just to monitor the activities of space walks. And those are my tasks on that EVA day.

Now on STS-72, you used the RMS to retrieve the Japanese Space Flyer Unit, and you supported two space walks there. If you would, compare and contrast your work on that flight with this mission.

It was a very exciting flight for me operating the shuttle's robotic arm to capture the free-flier satellite and also deploying another satellite and capturing that satellite 2 days later. So what is quite different on this flight compared to the free-flier capture is that, of course when you capture a satellite you have a limited time to perform the task after …after the space shuttle's attitude control is put into free drift. We have to slowly, but we have to capture the satellite within a certain timeframe. However, when I operate the shuttle's robot arm to capture the satellite, I had a very good direct view through the cockpit window and also I had a very good camera view that is located on the robot arm's end-effector. So, I can see the relative position between the robot arm to the satellite through the direct…direct view window and also from the camera view. But on this flight, for both PMA-3 and the Z1 installation to the Unity module because of the very small corridor that I have to stay within during the final approach of installation of those modules, I need to use a system called Space Vision System, which provides the RMS operator with a very precise positioning cues. So that is the most…different part of the robotic arm operation on this flight compared to my previous experience of retrieving satellites.

If you would, what are your thoughts about being the first Japanese astronaut to reach the International Space Station?

I feel very fortunate to be a part of this wonderful crew. But much more than being considered as a first Japanese to reach the International Space Station, I would like to emphasize that I am only one team member of the many international partners working on the International Space Station. So being the first means there will be more to come. And I really look forward to seeing my fellow Japanese astronauts work on International Space Station in the near future.

Now given the recent changes at NASDA and Japan's problems with expendable rockets recently, what do you think is the significance of the International Space Station to the people of Japan?

What is most significant for Japan is that the Japanese Experimental Module for the space, International Space Station called the Kibo module, it will be the first human space facility for Japan. And human space flight and International Space Station project have been well supported by the public thanks to the very successful US-Japan cooperative missions in human space flight in the past. And Japan will be participating in International Space Station in various areas such as developing the Kibo module and also Japan will be launching logistics carrier called the HTV - H-II transfer vehicle - that will be used as a logistics carrier between the ground and International Space Station. That carrier will be launched by a Japanese H-IIA rocket that launched from Tanegashima Space Center in Japan. And also in return for the launching cost of the Japanese modules Japan is developing a Centrifuge Accommodation Module for the US. And so with JEM Kibo module, HTV logistics carrier, and a development of the Centrifuge Accommodation Module, Japan is participating in various areas of the International Space Station. And I'm very happy to see that everything is going very smoothly in development and the preparation for launch. And after this flight, I'll be looking forward to working with more with the Japanese side to help them develop the assembly and operational procedures and et cetera.

Tell me a little bit more about the Kibo Experiment Module. What kind of work is going to be onboard the Kibo?

Okay. Kibo has some parts in it, and it has a pressurized module and also it has [an] exposed facility on which we can perform experiments utilizing not only the microgravity environment in space but also a high-quality level of vacuum for various experiments. In addition to those experimental modules, Kibo has two different kinds of logistics carriers. One is a pressurized one; the other one is exposed one. And also to handle the experiments on the exposed facility and also move around the Orbital Replacement Unit, there will be two different kind of robot arm that will be installed on the Kibo module. So it has many interesting parts in it.

Great. During the flight, you're going to be ingressing into the International Space Station. What are you going to be doing inside there?

Okay. We will be going into the space station after the Z1 installation is complete on Flight Day 4. And also, on Flight Day 9 we will be going inside the space station. And the tasks that we will do inside of the space station will be transfer, transferring various items for the first International Space Station…Expedition crewmembers and also removing the Common Berthing Mechanism components on the zenith side of the Unity module. We used a Common Berthing Mechanism to install the Z1 Truss to the Unity module, and we will be removing and bringing them back to Earth for future use. And our crew will be performing leak checks of the Z1 vestibules inside of the Unity module. And also we will be preparing the space station for the Expedition crewmembers' arrival. For example, we will be exchanging or replacing the filters for cabin air conditioning on the Zarya module. We need to bring various items such as batteries and a computer…computer hard drives and also procedures for the upcoming crewmembers.

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

Results obtained from the various experiments or observations on the International Space Station will create various fields of new technologies that will benefit us all on Earth. And I think it'll also expand our knowledge in various fields of science. And at the same time space station-the experience that we gain on the space station-will serve as a stepping-stone for us to build a lunar base and also going to Mars.

This flight is also the 100th flight of the space shuttle. If you would, tell me what you think about the uniqueness of the space shuttle and what its role is going to be in the future.

I think the space shuttle is the most versatile space vehicle ever designed and operational. And it has flown very many payloads such as on the experiments, such as the experiments on the Spacelab modules or on various satellites that was deployed and retrieved by the space shuttle. And space shuttle also has been providing vast opportunities for access to and from space-and not only for the US, but also for many countries which do not have access to space because of not having a space transportation system. And one good example is the Space Flyer Unit retrieval, which was launched by the Japanese H-II rocket. And I think the space shuttle will continue to fly more than a decade or two. And now the space shuttle is playing a key role in the assembly and also the utilization of the space station.

Image: Koichi Wakata
Click on the image to hear Mission Specialist Koichi Wakata's greeting. Japanese Greeting
Crew Interviews

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