Preflight
Interview: Nancy Currie
The
STS-109 Crew Interviews with Nancy Currie, mission specialist.
Can
you tell us a little bit about why you decided to become an astronaut?
I think it's
kind of interesting, especially for a woman my age, because when
we were kids growing up, women weren't military pilots. Women weren't
astronauts. And so, I'm like, I think, a lot of my male counterparts
who say, "Oh, from the time I was, you know, 4 years old, I
wanted to be an astronaut." It really wasn't a concrete goal
of mine until much later in my life. But I'd say from a very early
age, I knew I wanted to fly. I mean, I just dreamed about flying
probably from the time I could walk. And so, it was a very natural
progression for me to kind of enter the military and be a military
aviator first and go through that. And then, my advanced education;
and then finally achieve the dream of becoming an astronaut. But
it seems like my lifetime has always kind of been in the right place
at the right time, because it was when I was later on in high school
and the beginning of college when they started allowing women to
be military aviators. And then, I was already in college before
the first females became astronauts. So, it seemed like I was just
one step behind; and so by the time I got to that point in my life,
the doors were wide open and it was a very easy process at that
point.
Can
you talk a little bit about…a little bit more in depth about
the steps, academically and professionally, that you've had to follow?
I started out
I went to the Ohio State University and got a bachelor's degree
in biology. It was always my dream, when I was in high school I
used to dream about and read about, Army aviators flying helicopters
and extracting the wounded in Vietnam. You know, that was all around
that period of time. And so, that was really a goal of mine is to,
first, become an aviator and then maybe later on, a doctor in the
military and do that. But the military about the time I was graduating
from college opened up the opportunities for women to be appointed
in the combat arms. So, I actually became an air defense artillery
officer and went directly to flight school. And so, as soon as I
graduated from college, I entered the military and I went through
air defense training at Fort Bliss, Texas, and then right into flight
school. And I had never flown anything in my entire life; but I
knew I wanted to do it. And the first day in a helicopter - and
flying a helicopter is not all that easy or intuitive and they kind
of give you one control at a time and I think the first day they
give you the pedals, and the second day they'll give you the pedals
and the cyclic - and just as soon as I got in the aircraft, I said,
"This is for me! This is what I wanted to do." And flying
was just so enjoyable. I ended up staying at Fort Rucker, Alabama,
as an instructor pilot. To this day, other than the job I'm in presently,
it was the most fun, the most enjoyable job I've ever had in my
entire life! I just loved training flight students and sharing with
them the same enjoyment of flying and the discipline of flying that
I had. When I was in flight school, we actually had an accident
that killed my instructor pilots and two of the guys that I flew
with every day. It was just kind of a strange coincidence that I
wasn't in the aircraft. And it was at that time that I decided to
kind of devote a portion of my career and my academic life to safety
and safety engineering. So, that's why I got a master's in safety.
And then it was once I came down here to Houston that I then later
on received a doctorate in industrial engineering. Again with an
emphasis on human factors, safety engineering. Something I've always
held very close to my heart because I did see what catastrophic
things can happen, due to human error in the cockpit, or human error
combined with a malfunction in the aircraft.
Who's
been some of the, some of your biggest supporters, and maybe still
are and influences in your career and life?
My daughter
was born about a week before I was interviewed by NASA in 1987 for
the first time. So, I'd have to say in terms of supporter, she's
been with me from the start; and she's been with me through it all.
For the first 6 years that I was an astronaut, I was a single parent;
and so it was somewhat difficult, for a mom to have a lifestyle
like that, you know. Gone an awful lot on travel and studying a
lot at home. But she has enjoyed my career as an astronaut I think
as much as I have. [She] is very interested in it, from the time
she was, you know, 4 or 5 years old, could tell you a lot about
aircraft and definitely about the space shuttle. And then, in 1994,
when I was off training in the Blackhawk helicopter, I met my husband
Dave, and he's just been a tremendous supporter and tremendous help
to me. And just been the best thing that's ever happened to me.
So,
maybe your daughter may be a, I guess she has an eye maybe on your
career, too?
Well, most
people think, you know, she will. But she's a little bit conservative.
So, she's actually interested in meteorology. In fact, on one of
the "take your children to work" days, I brought her here
to NASA. And she spent the day with the meteorology group here at
NASA. And for about the last 10 years, she's said that's what she
wants to do. So, I think if I got her in aircraft just once, though,
I might get her hooked.
When
all is send and done and the STS-109 crew is done servicing Hubble
on this mission, what impact professionally and personally do you
think working with such an important scientific tool will have on
you?
I think it's
very similar to my last mission, which was the first International
Space Station assembly mission. Just to be a member of this incredible
team. I'd always heard about the Hubble team and what a fantastic
support structure they had. And once I was assigned to the crew,
I really realized what they meant. When we do some of our sessions
at the Neutral Buoyancy Lab, we'll have 30 support engineers in
the room that are anxiously awaiting our feedback, anxiously awaiting
to help in whatever way they can. So, just to be a member of this
incredible team that's been together for so long! And you know the
really enjoyable thing is that this is not the first time we have
serviced Hubble. So, a lot of these people have an incredible amount
of experience! So, they're not going through this learning process
about kind of the integration of their scientific or engineering
goals on the flight as compared to the operational aspects of it.
These guys are space operators; and they know what we do, and what
are capabilities are, and what our limitations are. And they are
just a tremendous joy to work with. The other thing that's somewhat
similar to STS-88 is that, at the conclusion of that mission, I
could take my family outside and look up in the sky and say, "You
know, I had just a little tiny part in what's flying overhead."
And you can do that with Hubble also. So, it's really neat to be
on a project that you can look up in the night sky and see it flying
over and see the results and see the impacts that it's making.
As
far as the mission, can you, first of all, as MS-2, and the primary
arm operator, can you talk a little bit about what your primary
responsibility is for this mission?
I'll address
the MS-2 part first. As MS-2, I will be seated just aft and right
between the Commander, who sits in the left seat, and the Pilot,
who sits in the right seat. It's my job, some people refer to us
as "quarterback." I know from flight instructing that
the guy sitting in the jump seat, if you will, has a big picture
because you're not so focused on the flying vehicle or, you know,
making keyboard entries or throwing switches. So, you can kind of
get this global picture. So, it's actually my job as a flight engineer
to recognize any malfunctions, to diagnose them, to send this off
in an appropriate corrective action, and also keep track of where
we are on kind of the nominal or normal steps. And make sure that
I'm kind of quarterbacking to make sure that everybody's in the
right procedure, on the right page, adjusting or helping with any
switch throws as necessary. There are certain switches, particularly
when we're suited, that the guys in the front just can't reach.
I'm flying with some very large guys on this crew. And so, my seating
height is quite a bit lower than them. And so, there's actually
some things that I can see in the cockpit that they can't see, just
because of my seating height. And I can look up and verify talk
backs, verify switch positions, and actually direct their hand to
certain switches. So, we always try to have two people on a procedure
that we agree, "Yes, this is the malfunction that we have.
This is the procedure that we're going to work. This is the exact
switch that we're on," because again, our visibility is somewhat
limited. And it really helps that crew in cockpit coordination to
make sure that we don't make an error. Once when we're [on] orbit,
if there was any malfunction, with the shuttle at all, it would
be primarily the responsibility of the Commander, the Pilot, or
myself to work those malfunctions, whether they be with a computer
or an electrical system. Again, those same sorts of things. On orbit
typically you might have a little bit more time, not quite as time-critical
as, say, in ascent (it only takes 8½ minutes). As the arm
operator on this flight, I can't think of another mission, that
will be a better mission to be on as the arm operator because, essentially,
every single day except launch and landing, we're using the arm
on this flight. And we'll be using the arm to grapple the Hubble.
We'll be using the arm on all five of the EVAs to maneuver the crewmembers
around. The arm makes a tremendous work platform. They can put a
tool stanchion behind them on the arm to hang all their tools that
they'll need off of it. And then, finally, when we go to release
Hubble, [it] will be the arm [that] maneuvers it in position, releases
it, and then we'll back away slowly with the shuttle.
Talk
about the rendezvous. Can you take us through that scenario? And
tell us what will happen with your duties? How Hubble will be positioned?
Just kind of explain it for us.
Okay. All seven
of us will be gainfully employed on rendezvous day. It's kind of
a trick [to] make sure we distribute the duties evenly, but that
we don't overcrowd the flight deck also because a couple of us will
be manually flying. Scott will be manually flying the shuttle, and
I'll be manually flying the arm at the final phase. And so, you
actually don't want too many people up there all at one time, and
so it's a big choreography. We've rehearsed who moves where. And
at one point we all kind of get up and switch seats. So initially
I'll be kind of floating behind the commander and pilot and assisting
them in computing all of the burns that we're going to do and actually
performing those burns, whether they be with the orbital maneuvering
system engines or the reaction control jets. Shortly into the rendezvous
then, Scott will start to move to the back, and Duane Carey, the
pilot, will move into the commander seat. And I'll actually be sitting
in the pilot's seat for a period of time, all the way up until we're
about 400 feet away from the Hubble. And so, the two of us up front,
Duane and myself, will be running the checklist, computing and manually
performing the burns, to get us in a position to rendezvous with
the Hubble. Then at 400 feet, I will move back to the back to kind
of get ready to take over the arm duties. But I'm still responsible
for primary rendezvous task, so I'll actually be using the shuttle's
camera to triangulate our position with respect to the Hubble so
that we can calculate our distance and relative position from it.
We do have a handheld laser device, very similar to what the police
use to stop you when you're speeding. And we'll be using that to
sight on the Hubble. Many of the flights, we use a trajectory control
sensor, in the payload bay, to calculate our position. But we do
not have that on this flight. Also due to the reflectivity of the
Hubble, our radar may not be exceptionally stable. So, it may be
what we call a little noisy, so we may see some, you know, kind
of errant positions in there. But the global picture should be good
as far as our distance and our rate of closure. Basically what happens
is we progressively lower our rate of closure as we get closer and
closer to the Hubble. Once we get to about 70 feet, we can start
to pick it up in the camera poised on the end of the arm. You know,
we'll [be] kind of poised, out over the port sill of the shuttle,
looking across starboard. And so, as the Hubble comes down into
the payload bay, the camera on that arm will be looking across at
it. At that point, Scott and I will start to determine, "Do
we need to maneuver the shuttle, you know, forward or aft to shift
the Hubble's relative position so it's perfectly centered?"
I think the interesting thing about the Hubble grapple as opposed
to say the grapple of the functional cargo block that I did on my
last flight is the Hubble comes down at an attitude of about 58,
52 degrees with respect to the payload bay. And that's because the
Hubble and the arrays are so massive that, due to clearance concerns,
to give us a little more clearance, we come down with it kind of
at a diagonal to the payload bay. So, what that results in is: once
we get it stable and we're ready for this handoff between Scott,
manually flying the shuttle, and when we're going to pick it up
and go over and maneuver the arm, I have to make a pretty big maneuver
with the arm in terms of yawing it and moving it to get it perfectly
aligned and then move in. We also have some kind of off-nominal
contingency situations where we may have to grapple it upside-down,
let's say, and so we practice all those sorts of things. If we have
to grapple it upside-down, then I'd actually have to roll the arm
180 degrees also. So, at that point, it's a very close choreography
between the commander and myself. We agree when it's time to put
the orbiter in a free-drift state and go in and grapple the Hubble.
At that point, he assists me; and we'll actually kind of count down
my distance to the grapple fixture on Hubble. Scott's very well-suited
to do that because he's my backup arm operator for the space walks,
so he's very familiar with the robotic arm. And then, Mike Massimino
will actually be my backup for the robotic arm, so he'll be watching
the display, watching microswitches, assisting me with any malfunction
should they occur during that final maneuver in to grapple Hubble.
You
mentioned clearance while bringing Hubble in. Roughly how much with
the solar arrays as big as they are, roughly how much clearance
do you have there? And how much do the, I guess, the cameras on
different parts of the arm help?
Yeah. The clearances
I'd say in station perspectives are not that close. I mean, we have
feet of clearance. Maybe even up to 10 feet of clearance. But just
to give us a little more safety margin is why we come down at this
diagonal. But many times we come down in what we call an orthogonal
attitude, which is a 90-degree attitude so we can perfectly see
our distance between the grapple fixture and the end of the arm.
We can also very clearly see any relative rates. So, it just makes
it a little more complex to do this arm maneuver, to come in and
grapple, but very safe and we have a whole lot of insight. And unlike
my last grapple, we have a great view out the window also. So, I
won't really be looking out the window. It's kind of like flying
an instrument approach in an aircraft. You're kind of very focused
on the target and the camera view that you have. And just like when
you're flying an instrument landing system in an aircraft, you know,
you try not to look outside too much. You're primarily focused,
and you let the other people in the cockpit look outside and tell
you if they see anything and count down your distance.
What
are your thoughts about…we were talking to Rick Linnehan, and
he mentioned, he said, "I don't want to put any pressure on
Nancy, but she's one of the best arm operators I've ever known."
What are your thoughts about that, having such an important job
with such an important piece of equipment?
On my last
flight, there's a lot of pressure there. There's a whole lot of
pressure. And it was kind of funny because after I'd grappled the
FGB, we had some press conferences. And people said, "Were
you nervous?" I said, "Well, heck yes I was nervous! Who
wouldn't be nervous? Because if I missed it, you know, we may not
have a space station. I mean, this is our critical piece! So, I'm
not going to kid anybody: there's an awful lot of pressure."
But there's an awful lot of pressures on [a] military aviator, too.
You know, you train day-in, day-out to perform this job; and you
know, we kind of say, "Okay, today is game day. And you know,
this is for real." And we try to treat every day in training
like that. I would feel as bad in training if I had a missed grapple
attempt as I would on the real day. And so, I've got a tremendous…amount
of backup inside the cockpit, a tremendous amount of experience.
And Dr. Jim Newman was the program manager for the shuttle arm;
and he was my backup for the arm on my last flight. Mike Massimino
has been working shuttle arm procedures and being involved in the
program even before he was an astronaut. So, we've got a tremendous
amount of experience! Scott Altman was a primary arm operator on
his last flight; flew the arm during the EVAs on his last flight.
So, I feel like I've got a lot of support there. And I always tell
them that, you know, even though I may have done this before that
their help is just invaluable. So, I won't kid anybody. I think
people are surprised when we say, "Well, sure there's a lot
of pressure! And sure we're nervous!" But I think you'd be
kidding yourself if you said, "No, I'm not nervous at all."
Yeah.
And maybe expounding on that a little bit…even having done
this before, using the arm to grapple, does grappling Hubble, and
the logistics of moving with it present, or anything else present
any more challenges that maybe you haven't faced before that you're
looking at?
Hubble, as
you know, is a fairly massive payload in terms of the satellites.
But so was the Russian element. And so in terms of masses, actually
the Russian element was slightly more massive. So I'm familiar with
moving large masses; and essentially the slower you go, the better
off you are. That is kind of my trademark, and I take a lot of grief
for going very slowly. It's kind of a joke around the Center of
who can fly the slowest? And definitely I think I win that prize.
But what I found is the slower you move it, then the less problems
you have, say, with oscillations in the arm, the controllability
of the arm. When you say, "Stop," the payload stops. And
because of the upgrades we've made in the shuttle arm over the last
5 years, and really tremendously increased the capability in terms
of mass capability of the arm, the arm flies exceptionally smoothly,
even with a massive payload like that. So, I think my experience
on the last flight, and I know there's some issues that come up
and some things that we think about and talk about, not only based
on what I've seen in my experiences as the chief of the robotics
branch, in the Astronaut Office but also from personal experience
in dealing with different-size payloads.
Let's
talk a little bit about the goals of the mission. Can you give us
an overview of the main goals of the mission? And just a little
background about what achieving those goals will accomplish?
Okay. I'll
kind of break them down, as most people do, kind of systematically,
almost by EVA day.
Okay.
So, on the
first two EVA days, we'll actually be changing out the solar arrays.
The solar arrays that are currently on there (and we refer to them
as solar array 2 because they've been on orbit; those are not the
original solar arrays launched on Hubble), and they've been on orbit
about 8 years. We'll be replacing those with a rigid solar array.
So, one of the first complexities that we may encounter is that,
for some reason the solar arrays that are currently on Hubble do
not roll up properly, there's all kinds of various stages of how
much they can roll up. But essentially, let's say if they were not
to roll up at all, we would actually have to jettison them out into
space. So, we would use the arm to do that. Position the crewmember,
it's a very intricate choreography for him to say, "I'm releasing,"
and for me to back away with the arm, and then to fire the jets
on the shuttle to separate away. When they repaired the…replaced
the solar arrays the first time, they had to jettison one of those
solar arrays. So, the best knowledge we have is we've got a 50%
probability of perhaps having to do that. So, that's a contingency,
if you will, that we've taken very seriously on this flight. One
of the things that the new solar arrays will do: first of all, it'll
leave Hubble looking different. They're about two-thirds the size
of the present arrays. And the other things is that being rigid
arrays, they won't be so prone to flexibility in terms of if we
fire a jet on the orbiter or if we maneuver the arm too
fast, with the rigid arrays. So, they'll be more robust. The other
thing, because this is an orbiting spacecraft, it's less surface
area, so therefore less drag. Because where we're leaving it is
not a pure vacuum; so there is some orbital decay that occurs on
Hubble. And so, this is less drag because of the less surface area
of the solar arrays. Even though there's less surface area, they're
going to produce about one-third more the power than the current
arrays. So, they're actually smaller but better-performing arrays.
So I think it'll be a tremendous enhancement. On the third day (we'll
be replacing one each day, that'll be the first two days of the
flight), on the third day [we'll] be replacing the power control
unit on Hubble. So for the first time since it was launched 11 years
ago, we're going to power Hubble completely down. There's some inherent
risks just in doing that because what if it doesn't power back up?
But you know, of course we have looked at that in many, many different
ways and many different scenarios. And we feel certain that this
procedure will be very effective. And once the new power control
unit is in place, of course, then it will transform the power from
these new solar arrays and the batteries to the spacecraft and leave
it in [an] operational condition. On the fourth day is when we do
something really interesting. We're going to replace a camera system
with the Advanced Camera for Surveys. And the Advanced Camera for
Surveys is a scientific instrument. It's probably about the size
of a phone booth, is probably a good corollary for that. And it's
actually three camera systems. And it will just tremendously increase
what scientists can see into the universe to explore the origins.
So we're really looking forward to being the ones to emplace this
new camera system; and then, you know, watching and seeing the results
as those images come back from Hubble. And then on the fifth day,
we're going to replace or install a new coolant system for a camera
that was emplaced in 1997; and that camera's called NICMOS. And
it's a near-infrared camera multi-object spectrometer. So, that's
what NICMOS means. And it was replaced in 1997; but for about the
last two years, it hasn't been able to be used because it was launched
with a cooling system that has since been depleted. And so we're
going to actually hang a very large radiator. This radiator essentially
almost spans the width of the payload bay of the orbiter. The payload
bay is about 15 feet wide. So, this radiator is just shy of that.
So, you can imagine! It's a fairly massive radiator. I'll actually
be maneuvering John Grunsfeld on that day. He'll pick it up; he'll be on the end of the arm. I'll roll him up in the vertical position
and stand him up with it. And so it's pretty massive as he comes
around. And we'll be watching the clearance with the arrays on the
Hubble as we bring him around to hang and install that radiator.
So, again, I think that's a very important aspect of the flight,
because we'll be essentially returning that scientific instrument
to an operational and usable condition.
Can
we go through each EVA again, and this time, kind of illustrate
with us exactly where you'll be maneuvering whom to where.
Okay.
different,
different--
But there's--
--locations.
--you know,
there's a whole lot! I'll do it--
Can
we nutshell it a little bit.
Yeah.
Okay.
We'll start with EVA-1 and -2. And just EVA-1--
Yeah, they're
almost similar.
--because
-2 is basically the same.
Now, on EVA-1
and -2, we'll be essentially performing the same task, but with
a different team. So, the EVA-1 team, which will also do EVAs -3
and -5, is John Grunsfeld and Rick Linnehan. John, of course, was on the last Hubble mission. He's been invaluable to us because he's
very familiar with the Hubble. And they'll actually share time on
the end of the arm. Rick Linnehan will start out on the end of the
arm; but about three-quarters of the way through that EVA, we're
actually going to switch positions to give Rick some free-floating
experience prior to going in to EVA-3 because of its complexities
and its high amount of workload to change out the power control
unit. Essentially what we'll be doing on that flight is the very
first thing we need to do, is to get that old solar array off. Again
the night before that EVA, the end of the rendezvous day, we're
going to send the commands to retract those arrays. So we'll know
going out the door whether that retraction was successful or not
and whether we can then berth it in the payload bay. There's a carrier
in the very forward portion of the payload bay called the rigid
array carrier. We refer to it as "the rack." And he would emplace
that rolled-up array in the rack; a very similar mating interface
to what mates on the telescope. So, from the very first time they
come out the door, they will be, the very first thing we'll do is
put the arm back about three-quarters down the length of the payload
bay. And the foot restraint that they stand in, we actually grapple
with the shuttle arm. So John Grunsfeld will hold it up. He'll actually maneuver it so it's perfectly aligned with the end-effector. And
then, I'll actually grapple it. It's different than what we do on,
say, space station flights where we put a, what we call PFR attachment
device. We actually put it on top of the arm and then mount the
foot restraint to it. So, Hubble's unique in that you grapple this
foot restraint to the end of the arm itself. The only reason that's
unique and the reason I bring it up is because we do not end up
stowing the arm in its normal position between EVAs.
Okay.
We actually
leave this grappled. And we leave the arm poised out over the port
cell of the orbiter overnight. And that way if we had to come home
in an emergency, we could quickly jettison this device, put the
arm back in place, and come home.
Okay.
So once that
device is in place, we'll come back through the airlock. Rick will
get in the foot restraint, and then we'll be ready to maneuver him
back to take off the array. Every time we're working with an array,
essentially the free-floater's kind of at one end, the guy on the
end of the arm is at the other end. He'll actually hold on to the
array, and I'll back him away and then move him down to the carrier.
And then, when we're ready, we're going to change out a small, diode
box assembly. That diode box assembly is particular to the type
of array that's on. So before we put on the new array, we put on
this new diode box assembly. And then we'll be ready to install
the new array. The new array installation is kind of interesting.
It's again the choreography between the arm and the EVA crewmember,
because I could be maneuvering the arm very slowly, but if he starts
pushing away with his arms, it would look like the same thing. So,
we've kind of got a protocol that says whenever the arm is moving,
the EVA guy is not moving. And then, when he's ready to push, we
build up a little bit of slack in his arms, when he's ready to push
for the final installation, we'll actually stop the arm. And that
way you kind of decouple what the crewmember's moving and what the
arm is moving. And again, if we should get into a solar array jettison
case, we again would maneuver the crewmember pretty much centered
in the payload bay, fairly high, and he would let go. We would back
away the arm with him on it. The solar array, which is now floating
there, we would then separate by firing the jets on board the shuttle;
and the solar array would separate from the payload bay. So, we're
also prepared to do that. Again, we should have some indication
as to whether or not that will be necessary at least from the night
before.
Okay.
Then on EVA-3,
again it will be Rick and John. And when we do the power control unit, that installation, once we get the new, or once we get the
old power control unit out, it's a series of, you know, 38 connectors
that they're going to be manually demating and inspecting with an
inspection mirror! So you won't see a whole lot of massive maneuvers
with the arm. You'll see very small maneuvers. You'll hear the crewmembers
just requesting a couple of inches or two to the right or left,
or up or down, or just a little bit of pitch or yaw in their body
so that they can get a good purchase on the connectors themselves
to get them off. There was a special tool that was designed to remove
those connectors. And we're hoping that because those connectors
have been in place for 11 years and now in the harsh environment
of space, we're hoping that they demate as easily as we have seen
in ground testing. Then we'll remove that power control unit. We'll
get the new one and install it. And again other than a maneuver
down into the payload bay to its storage assembly, again you'll
see very small maneuvers. We actually disconnect several of the
batteries in some of the bays. So, we'll be maneuvering to some
of the adjacent bays, opening up the doors, disconnecting, reconnecting
the batteries.
Where
will the main activity take place?…at which bay?
--the main
activity is in bay 4--
Bay
4.
--where the
power control unit is..
A
little bit maybe about…you mentioned choreography and communication,
which there has to be a lot of between you and the EVs…is there
a system that's been worked out as far as communicating, them communicating
to [you] where they want you to take them? And I mean, nothing's
foolproof, but is there some fail-safes, kind of [to] make sure
that there's an understanding [of] exactly what they're talking
about?
Yeah. In terms
of the protocol between, say, the robotics crewmembers inside the
shuttle - and of course, we're on the aft flight deck, we're looking
at monitors, we do have the opportunity to look out the windows;
as opposed to the main of the station flights, of course you're
looking at where the station is docked to so you don't have a lot
of good out-the-window views - so we have the pleasure of actually
being able to see these guys right out our window working. So it
makes it somewhat easier. But we have a very standardized protocol
in terms of the communication between the EVA crewmembers and the
robotics crewmembers in terms of how we want the arm maneuvered.
The other thing is that in our preflight time, we take a lot of
time to determine the optimum body positions, the optimum arm positions
that they need to be in to work on the telescope. For example, when
we're emplacing the Advanced Camera for Surveys, we're actually
putting Jim Newman inside the bay, inside the telescope. And so
we really, very acutely watch clearances between the arm and particularly
the end-effector and the camera on the end-effector, his foot-plate.
Again, because we grapple it, his foot-plate sticks out from the
end of the arm a bit; so many of the times we'll be looking at foot-plate
clearance. If our cameras are not sufficient to do that, because
that's kind of in our line-of-sight, you know, he's kind of right
in the payload bay, he's facing aft, so your depth perception is
not that great to determine, say, three or four inches of clearance,
in many cases we'll be down to that type of clearance. We'll actually
have the free-floater, so Mike Massimino, for example, will go down
to that area and will say, "No, you've got six inches. You
can bring him in another three inches." Hopefully the models
that we train with, not only in the Neutral Buoyancy Lab but also
in the Virtual Reality Lab, are very accurate so that we know that
what we've seen in our preflight training is very doable on orbit.
But the protocol, when he says, "Pitch me down five inches,"
we know exactly what that means. Or "body yaw, body roll, bring
me in towards the telescope, out of the payload bay." So we
practice that. If there's ever any disconnect, I will always kind
of repeat in another frame, command frame. So if he says, "Bring
me to my right," I might say, "Do you mean to the portside
of the orbiter?" And just to make sure that, because our clearances
are so tight, that we don't ever put in a command that he's not
expecting that might take us even closer to structure.
If
you would, take us through the scenario [of] ungrapple and deploy.
What will you be doing for that?
Okay. I firmly
believe in giving rookies a chance to really do things on the flight.
So this is Mike Massimino's chance to fly the arm with Hubble on
it. And so Mike's going to go in and he's going to grapple the Hubble
when it's still connected to the flight support structure in the
payload bay. And then he's going to do the unberthing. Once he unberths
it and has it about a little bit over five feet above that structure,
then I'll take over and maneuver it into a release position. That
release position looks very, very similar and essentially identical
to where we grapple the Hubble. Once I get it there, again it's
a very tight choreography in the cockpit between sending some limited
commands to Hubble, making sure we have good communication with
Hubble, and then getting ready in the cockpit to manually separate
by firing [the] reaction control jets. So we'll set a countdown
timer. Once we get to zero, I'll go ahead and open the snares on
the end-effector. Then I'll go ahead and slowly maneuver clear of
the grapple fixture. Once I'm clear of the grapple fixture, though,
that's the one time I've agreed to fly the arm fast because we want
to get it out of the way.
Right.
We want to
get it out of the way, and we want to get it clear pretty much as
quickly as we can. So that as we fire the jets on the orbiter, the
arm is nowhere near the Hubble. It's a very interesting separation.
It reminds me, on my second flight, we deployed a TDRS satellite,
a very massive spacecraft that, when it launched, kind of launched
right over the cockpit. And you know, when you see this, you know,
very massive spacecraft coming just feet over your head, it's very,
very impressive. The Hubble has that same type of trajectory that
takes it basically right over the crew cabin in its initial departure
from the shuttle. So there should be a lot of picture-taking and
a lot of "oohs" and "ahs"; but we'll be very,
very focused on the choreography between getting the arm released,
getting those initial pulses in to start our separation away.
How
does it feel for you to have such a, I guess, an emphatic respect
from your cohorts. They all sing your praises. What's that like?
They've never
said that to me! I guess I'm overwhelmed by it because I don't ever
view myself that way. And I always, as I walk into any training
situation here, every single day I still learn or relearn things.
Even instructors who have been here maybe one-third of the time
that I've been at NASA will come in and teach me something new every
day. So never for a second do I think that I've got a particular
system or a particular area mastered. I'm always trying to improve
and always know I can do better. And so I'm going to keep doing
that right until the day I leave.
It
sounds like the game of golf.
You're right.
Can
you give us a little background about why EVA-3 is so critical?
And why it's expected to be, to do its timeline longer than the
rest of the EVAs?
EVA-3 is a
very crucial part of this flight. And again, in order to change
out the power control system, it involves un-powering Hubble for
the first time. And so we want to be very particular about the manner
in which we do that. The other thing is that there's a multitude
of connectors on this power control unit. It was initially never
designed to be changed out, quite frankly, especially via EVA. But
it's something that in the development of servicing missions and
the development of new tools, it's been deemed appropriate, an appropriate
task to go ahead and change this out. However, again those connectors
had been in place for a long period of time. There are some former
missions with some history of having some difficulty getting those
connectors off. Not these particular connectors but other connectors
after they're, you know, subjected to this extreme environment of
cold and heat and all these cycles for a long period of time. And
so even though we can do this particular space walk in about 6½
hours in the pool, we're fully anticipating that we may run into
some snags on orbit that pushes us a little bit longer. And quite
frankly, normally we kind of worry about it and really try to keep
EVAs down around 6 hours or 6 hours and 30 minutes. This was deemed
an acceptable risk, that if it took 7 hours or 7 hours and 30 minutes,
it was deemed important enough for the Program to do. So I don't
think anybody should be surprised if we, you know, kind of (quote)
"run long" because we won't be surprised if we run a little
long. And we're just very methodical in the way we do things; and
think it's much better than to, say, try to really rush through
a procedure. So it really will depend on how kind of finicky these
connectors are. If we have no problem getting them off and getting
them back on, probably will complete it in plenty of time. But you
know the first connector that, say, fails to come off, then we're
going to run into somewhat of a problem. And so we'll have to deal
with that at that time. So, it's kind of a watch-and-wait situation
on that EVA. We do have particular areas where we can (quote) "break
out" of that procedure and leave the Hubble in survivable condition.
The kind of basic premise on the flight is every day, before they
come inside, we want to leave the Hubble in a condition that should
we have to come back to Earth immediately due to a huge cabin leak
or a fire, something catastrophic inside that would cause [us] to
do [an] emergency deorbit, that Hubble could still survive. That
we could send it back out into space. And it would require more
servicing at a later date, but it could still survive. So that's
kind of the premise on, you know, how we want to leave the Hubble
when we complete a space walk.
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