NASA Headquarters Oral
History Project
Edited Oral History Transcript
William H. Gerstenmaier
Interviewed by Jennifer Ross-Nazzal
Washington, DC – 17 August 2017
Ross-Nazzal:
Today is June 7th, 2017. This interview with Bill Gerstenmaier is
being conducted at NASA Headquarters for the Headquarters Oral History
Project. The interviewer is Jennifer Ross-Nazzal, assisted by Rebecca
Wright. Thanks again for taking time today, we certainly appreciate
it. We know your schedule is quite busy.
Gerstenmaier:
Thanks.
Ross-Nazzal:
We wanted to start with your time at the [NASA] Lewis Research Center,
now the [NASA] Glenn Research Center [Cleveland, Ohio]. You started
working there after graduation from Purdue University [West Lafayette,
Indiana], and you went to work in the Wind Tunnel and Flight Division.
Had you been a co-op [cooperative education student] or an intern
at that point? How’d you find out about that opportunity?
Gerstenmaier:
No, what happened was at the university the various recruiters came
in, and then you got a chance to go interview with folks that came
in. Somebody came from the Lewis Research Center at that time, and
I did an interview with them. I was kind of interested in propulsion
and aeronautics. My background was more on the propulsion side from
school for my B.S. [Bachelor of Science] and with interest in aeronautics,
so I’d interviewed with a lot of different companies. A NASA
recruiter came through and said—kind of typical to even where
we are today—there weren’t many openings. They weren’t
hiring very many folks, but they would go ahead and give it some consideration
to see if I could go to work there.
It was an interesting recruiting process overall. I had interviewed
with a lot of different companies, with McDonnell Douglas [Corp.],
with General Dynamics [Corp.] in San Diego [California], with General
Electric [Co.] in Cincinnati [Ohio]—all in the aeronautics world—and
Pratt & Whitney also. What was intriguing to me was that almost
all those companies had some relationship back to NASA.
So then the question for me was, “What did I want to do?”
Did I want to go work in one particular area of aeronautics and be
pretty stovepiped? Or did I want to go to NASA and then actually get
a much broader exposure to a much larger industry? I thought “Boy,
it’d be kind of neat if I got a chance to go to NASA and do
that broader industry.”
It was interesting. Of all my salaries that I was offered, NASA was
the absolute lowest. I still remember my starting salary was $13,056,
which is absolutely amazing. It was the lowest of any offer I had
from any company. I didn’t realize—at the time that wasn’t
a big consideration—but I just thought the value of the work,
and the chance of being in the oversight role would be really good.
It turned out for me I think to be, first of all, really good to go
into wind tunnel and flight and test. I think it’s really good
to do some hands-on experience early in your career. I got that same
advice from many of the companies I interviewed with. I did not do
a co-op term with anyone, but I got that advice to go do something
that was practical, more hands-on. Because later you can do the analytical,
you can do the programmatic, you can do the operations stuff. If you
have a good solid test background, it’s really something unique
to get early in your career. So that was another advantage of going
to Lewis at the time.
Again, I think that’s how I came about selecting Lewis. I was
lucky they had an opening. It was a tough time at Lewis because they
were still in the reduction-in-force timeframe after Apollo. They
had gone through significant personnel reductions over that timeframe.
I don’t think they had hired anyone in about five years, so
I think myself and another employee were the first two employees to
come to Lewis in about five years. There was not a whole new group
of interns or students or employees coming in. There was like two
of us, so it was pretty small.
It was a great environment to go into. All the people I worked with
were really senior researchers. Most of them had written my textbooks
or had contributed to textbooks that I had done in aeronautics. So
I was getting a chance to work firsthand with all these folks that
really, really understood aeronautics. They were tremendously nurturing
and really helping me to grow in my career.
There was a program kind of like we have today where you get assigned
a mentor. I was assigned a mentor, and his name was Joe [Joseph F.]
Wasserbauer. He was just a great person. He was doing supersonic research
and wind tunnel work. Just an unbelievably great expert, and he would
just spend the time. There wasn’t a question that I couldn’t
ask him that he wouldn’t find time to go answer.
They put me in the wind tunnel very early, doing wind tunnel tests.
I did some early Space Shuttle stuff, some other activities with them.
I did some supersonic inlet work with them, doing some analytical
papers, but my job was predominantly to do test data. Then the test
data would be compared with the analytical results or computational
fluid dynamics [CFD]. The idea was to then improve the overall computer
fluid dynamics models and to build how-to procedures for how you used
the new models based on wind tunnel data. What step size you pack
in place, how you set the mesh size for analysis, other pieces. It
was a tremendously great learning environment.
I ended up working third shift a lot, in the middle of the night doing
wind tunnel stuff, but it was great. I was actually in charge of running
the wind tunnel probably within the first year, and this is the 10-by-10-[foot]
supersonic wind tunnel. There was a one-sixtieth-scale Shuttle model
that went into the 10-by-10 supersonic wind tunnel. It had the orbiter
and the external tank and the solid rocket boosters. We tested all
those various configurations, provided the data to Rockwell [International],
then they used those to essentially verify the Shuttle ascent models
and the Shuttle data models.
We also participated in air data probe calibration. Those are these
little probes that pop out at Mach 3. We actually calibrated those
little tiny probes, so we had a very large-scale nose of the Shuttle
with two little probes that pop out the side. We provided the calibration
data that then went into the Shuttle algorithms to have the Shuttle
land on the runway.
What was interesting was those tests were done at Lewis in the 10-by-10
tunnel, they were done at [NASA] Langley [Research Center, Hampton,
Virginia], and they were done at [NASA] Ames [Research Center, Moffett
Field, California]. The results from the three tunnels were slightly
different. They didn’t yield the same calibration curve to determine
your airspeed and angle of attack and yaw. So the big debate was which
tunnel was right?
We got in a great debate between the three Centers about whose tunnel
was right. So then I spent a significant amount of time actually calibrating
the 10-by-10 wind tunnel itself. We put a big probe in there, like
you’d see on the front of an aircraft or a supersonic airplane
with a supersonic probe, and then we surveyed the entire dimension
inside the tunnel to show that our data was more accurate than any
other Center.
We had to get accuracy within like a half a psf [pounds per square
foot], which is a fairly tight accuracy. We uniquely calibrated each
individual pressure transducer, made sure that it was right. We did
everything possible to make this super accurate, because otherwise
when the Shuttle came down you wouldn’t make the runway. You’d
either be long, short, or it just wouldn’t fly right.
We debated and debated and debated—and I was a brand-new employee,
I didn’t have any idea what was going on. I would go to all
these meetings and there’d be these huge debates about whose
wind tunnel was right, what curve was going to go into the Shuttle.
Finally, in the end, we could never really decide. So we took the
results from all three tunnels, and we root sum squared them together.
It’s a mathematical way of averaging the results to actually
build the calibration curves that went into the Shuttle.
The cool thing was then later I go down to [NASA] JSC [Johnson Space
Center, Houston, Texas], and I hear how these air data probes work
and how they operate and how accurate they are. The folks that are
telling me this have no idea that I actually know how all this was
built and how it all came about. The myth was radically different
than the actual reality of the way we put these together. It was serendipity
that I went down to JSC and got to see that other side. It was neat
to see how the data that we took out of the wind tunnel then got used
by a whole variety of folks, because I didn’t know exactly where
the data went. I would take the data and then provide the data to
Rockwell or whoever, and it went off into the system.
That’s how my career started at Lewis.
Ross-Nazzal:
That’s an interesting opening. Would you tell us about wind
tunnel tests? Can you walk us through? What did you anticipate it
was going to be like when you first started there? What did the old-timers
tell you about using a wind tunnel and how to operate it?
Gerstenmaier:
The wind tunnel is really unique. The 10-by-10 tunnel is a phenomenal
tunnel in the fact that it can be run open-cycle. What that means
is you can actually have a full-scale jet engine in there. There were
some [Lockheed] SR-71 [“Blackbird” aircraft] engines in
there, supersonic engines. They were actually running, and they would
run all the way up to Mach 3, Mach 3.5, all the way down to Mach 1.
This is the largest supersonic section of wind tunnel around.
We did a lot of work. The folks I worked with actually built the tunnel,
so they would show me how they did the tunnel design. You have a nozzle
up front that accelerates the air coming through, essentially huge
compressors. You pump the tunnel down to a lower pressure, about two
psi [pounds per square inch] or three psi, and then you use these
huge compressors to just flow the air around. They go through a nozzle.
Then there’s a secondary throat after the test section where
you can reclaim some of the energy and expand it back out.
All that was done basically with slide rules, and there was a book
called the Ames Tables which show the shock angles that sit at various
flow conditions off of objects and pieces. Those tables and that manual
lookup stuff was used to design these facilities. The throat that
moves is actually large stainless steel plates. They’re maybe
about two inches thick, and they’re driven by hydraulic rams
that actually change the throat section, and that gives you the variable
speed going into the test section.
For me it was a great chance to see all the aeronautics that I had
learned academically in school. And now see how it actually gets applied
in the real world, and how you actually use the equations and how
you use these tables. How do you actually get the flow to go do what
it’s supposed to go do, and what is total temperature, what
is total pressure, what is Reynolds number. All these things, I got
a physical feel for what those were, and they were no longer just
academic abstract ideas. They were physical things I could go see
in the tunnel. I could go demonstrate, I could make changes in the
physical hardware, and then see how it affects the flow and other
aspects. The practical nature was just huge to build off of the academic
world I had done. So again, it was just a tremendous learning experience
academically.
Like I described, I also got stuck in to go run the tunnel, because
nobody wanted to work at night. So that even helped me later in management
experience, because now I’m in charge of these technicians that
are running the tunnel. Here I am, fresh out of school, brand-new.
These guys are very experienced technicians, really, really good at
what they do. Most of them would work other jobs, and then they would
come in and work at night. The technicians we had, they were all civil
servants at the time. The tunnel was totally operated by a civil servant
workforce. That was unique in the fact that later they became a contractor,
and then there was a more formal relationship between NASA and them.
But when I was there they were all civil servants. You would just
work with them. “How do I motivate them to work extra hard and
to help me get the right wind tunnel conditions?”
We had to run at night because we competed with electricity for Cleveland.
The cost of running the tunnel was about I think $1 per second of
on-time condition. That’s like $3,600 or whatever it is per
second of run time. It was very expensive, so we would call the electric
company and we would negotiate with them when we could go run. There
was a lake in New York that they would pump up at night with water,
and then they’d let the water run through during the day to
run turbines to provide power to the grid. We would compete with this
lake in New York. When they were not pumping the water up in the lake
for the next day, then we would be able to go run the tunnel.
So that was a big, interesting dimension of now I’m negotiating
with the power company when we’re going to run. Here I am really
inexperienced, thrown in this whole world, and they just delegated
to me the responsibility to manage a small team of contractors, to
negotiate with the power companies, to set everything in place. Just
an unbelievably great experience to learn that stuff.
You see later in your career how all that plays out, but it was just
phenomenal. I don’t think I can ever thank the folks I worked
with there enough. They really gave me a strong basis in engineering.
They gave me a strong basis in management. They really, really helped
me from a career standpoint. I’m indebted to them today. I can’t
think of a greater place to go.
Also, like I described before, it was unique in the fact that they
hadn’t had anybody new for a while. Here I was as a freshly
new employee, basically the age of most of their kids, so they really
almost accepted me just as a kid or a parent. It was an unbelievably
positive nurturing experience. It was really, really, really, really
good. That’s how I guess I would describe the tunnel activities
and pieces.
Ross-Nazzal:
How many people were on the team? You mentioned you were overseeing
a team of folks.
Gerstenmaier:
I would say it was probably about five people during a typical wind
tunnel test at night. We would typically come in like at 10:00 or
11:00 at night. We’d get on station, pump the tunnel down, negotiate
with the electric company, and then begin the actual runs at night.
That’s the way it went.
There’s a couple pictures of me in the tunnel when I was there.
That was also intriguing for me, because I was very much focused on
wanting to do wind tunnel tests. I remember we delayed one test because
we wanted to have a picture of us in the tunnel to try to get on the
cover of Aviation Week [& Space Technology magazine]. I’m
just like, “No, no, no, we need to go run. We don’t need
to get this picture. We need to go get data because this needs to
go to Rockwell to go satisfy some analysis they’re trying to
go do.” But then I learned the importance of sometimes you have
to show the broader community the importance of what you’re
doing. It’s not all just about getting the data. It’s
also leaving a physical record of what you’ve done, and let
other folks see what’s occurred. That was, again, just a tremendously
great experience.
We had huge challenges in the tunnel. One night we left one of the
hatches open, and it sucked in a bunch of debris, gravel and dirt
from the outside. Then that pelted the front end of the Shuttle model
and caused some minor damage to the Shuttle model. The worst thing
was it put dirt into the tunnel. We spent multiple days trying to
clean the dirt out of the tunnel, because it would be in other locations
and other pieces.
That was one thing where I learned the importance of being very focused
on all the details. It’s not just getting the tunnel up. “Are
all the hatches really closed? Have we really done all the walk downs?
Have we done all the preparation before we actually go do the start
of the tunnel activity?” That gave me another chance to see
that dimension.
One night we were running, again, the sixtieth scale model of the
Shuttle stack, and we had solid rocket boosters on the side. The instrumentation
was actually inside the solid rocket boosters. So when you’re
running at like Mach 3, the very front end of the model is extremely
hot, is really warm. As the shock wave forms, the temperature drops
to very, very cold at the back.
We had these pressure transducers we were using to measure the pressure
inside the model, inside these mock-ups of the solid rocket boosters.
They were water-cooled. We had a water-cooled system in there to keep
them—because the front of the model would get hot, we needed
to keep those pressure transducers at a stable temperature. So there
was water loops that kept them at those temperatures.
One night we were running, [and] something happened. First of all,
we saw a fuse blow in one of the controllers for these pressure transducers.
They were called Scanivalves. They had one pressure transducer in
the middle, and then they had like 72 ports around the side. The little
device would rotate around, sample each pressure port, expose that
to the pressure transducer, and then it would get recorded in the
data system. We were running at night and a fuse blew that was driving
those little Scanivalves to do the rotation of the pressure thing.
I didn’t know what it was. Then we changed the fuse out, we
put another fuse in, we ran for another minute or two, and the fuse
blew again. We thought “Hmm, wonder what that is.” I didn’t
know what to do. We put a third fuse in, the third fuse blew. We finally
ran out of fuses.
Then I had somebody [say], “Well, we can go look in the window.”
We looked in the window, and out of the back end of the solid rocket
booster was this large icicle, probably about three or four feet long.
What had happened was one of the water lines broke inside the solid
rocket booster, which provided cooling, and it shorted out the electrical
system. That’s why the fuses were blowing. We didn’t know
that. The back part of the model, because it’s behind the shock
wave, is like at -300 degrees. So that water essentially froze as
a solid piece just straight out. There was this solid icicle right
out the back of the solid rocket booster about three or four feet
long.
It was pretty amazing when we saw that, because it showed you the
physics of what’s going on. Here the front of the model is 100
degrees. After all these shocks it’s -300 degrees such that
that water just leaks out and instantly freezes. It gave you that
physical thing. It was humorous, because then we essentially broke
off the icicle, we put it in the freezer, and we tagged it. We kept
it. As I described to you before, the run time was like $1 a second.
We determined this must be the most expensive ice ever made in the
history of the world. We had some Christmas party, so I think we broke
up the icicle and used it as part of the ice for the activity we had
at Christmastime.
What I learned out of all that was first the physics of the engineering
side, but then also the fact that when a failure occurs, you need
to now think about, “Why did the fuse blow?” We should
have looked out the window at the very beginning and not continued
to keep running and just change out fuses. So again, that was another
piece of learning that was important later in my career.
I can’t stress how much fun and really great opportunity it
was to just learn how to become an engineer. That’s essentially
what I learned at Lewis during that timeframe, was really how to become
an engineer.
Ross-Nazzal:
How did you capture that data? Were you taking photos, film, magnetic
tape?
Gerstenmaier:
We had a computer system. The pressure transducers were calibrated
with signal conditioners. I think the high-speed data was captured
as analog data, and then the slower data was captured as digital data.
There’s large data books available, and they were on big disks
that were kept on essentially mainframe computers off in another building
someplace that would actually do that. We were at the transition between
digital data systems and analog systems. So a lot of the systems in
place were analog, where they just recorded the actual value of the
current coming through a device, whereas some stuff was starting to
get done digitally.
The other advantage to me was I came out of school, so I was very
familiar with computers and digital stuff, whereas many of the folks
I worked with were not experienced with the digital world. I would
do a lot of stuff on the computer. I would do a lot of stuff digitally
that they were not used to doing. They would typically do analog.
Even model control, where the model sits in the wind tunnel—that
was driven by an analog system instead of being driven by a digital
system as it would be today. I got a chance to experience that transition
from the analog world to the digital world. That was another piece
of my career that was really important.
When I wasn’t in the 10-by-10 then I did some subsonic mixer
nozzle work, which was looking at the back end of a [Pratt & Whitney]
JT8D engine. The fan stream is the stream that goes around the turbojet
engine. The core stream is the hot center stream. If you put a nozzle
at the back and you mix that fan stream and the core stream together,
then you exhaust through a common nozzle, you can gain an efficiency
in propulsion. You see it on modern aircraft today where they do this
mixer nozzle thing.
I was in charge of an activity where we were looking at the shape
of that nozzle that does that mixing between the core stream and the
fan stream. My job was to go look at design parameters along with
computer code that could help a designer figure out the way to design
that nozzle to be the optimum for a particular engine. We had a facility
over in Central Engineering 22 where we used to run the model at night.
I was responsible for doing the model design, doing the program design.
Again, tremendous firsthand experience.
What was intriguing also at that time was at Lewis there wasn’t
like today—as a designer or an engineer you do some of the work,
then you typically have somebody check your work, and they’ll
sign off on the drawing as well as you. In that timeframe, as an engineer
I signed off for the engineering that was being done, I signed off
for the safety, I signed off for the stress, I signed off for the
thermal. I did all that. There wasn’t an independent group to
go look at that. When we put a probe in the wind tunnel, or I put
a probe in this other behind-the-mixer nozzle—whether that probe
was designed strong enough to not break off and get sucked down the
wind tunnel, that was up to me to make sure that probe was designed
that it would work properly and it wouldn’t fail.
As a new engineer I was really scared, because I knew how to do some
things—I could run finite element analysis, I could do some
structural work, I could do some thermal work—but I just didn’t
feel I had the experience to really know everything that was required.
So I would do a design to a certain point, then I would go find the
smartest people I could find that I knew on the Center, and I would
go talk to them one-on-one. I would go, “Is this okay?”
I would make them check my work to make sure that what I was doing
was really right.
It was also really good because I got to see the breadth of engineering,
from designing on a computer or designing on a board, all the way
to fabrication and manufacture. In today’s world I don’t
think you get that. You’ll get to see one piece of the process,
but you very rarely would get to see the entire process.
For example, on the mixer nozzle stuff, I would actually do designs
of those. I would actually draw up the design. Then I would actually
work with the draftsmen to do the drawings and manufacture. Then we’d
work on the contract, go get it contracted, and built. Then we’d
come back and go test it. Again, I got to see all the way from design,
through fabrication, through test, and actual results back.
The beauty of all this was I got an unbelievable experience of seeing
engineering and how it really works firsthand. Again, the draftsmen
were all civil servants. There wasn’t a contractual relationship.
I could draw something up in the morning—if I wanted a new probe
or a new device, I could take it over to the draftsmen. They would
verify that it was right. I could take it over to the machine shop,
have it manufactured. I could be in the wind tunnel with a new design
the next day. It was a totally different world than where we are today
with much more compartmentalized, much more segmented work, with a
lot of contractor interfaces, lots of procurement interfaces. Just
a tremendous learning experience, getting a chance to go work with
those folks.
I will tell you again, the instrumentation people were the number
one in the world at Lewis. We designed these little devices to sit
in the back of the mixer nozzle to measure the velocity. Typically
you would want to do that with a laser device, but they manufactured
these little tiny probes that would measure velocity, direction, and
angle of attack of the flow coming out of the mixer nozzle. We built
a rotating shroud that would then rotate the probe behind the back
of the nozzle, so we could survey that entire profile of the back
of the nozzle. They did all the design of all those probes, then I
got to calibrate the probes. So I went to a freejet facility, calibrated
the probes, built the data, then actually built the algorithms to
take the raw data from the test setup, and then actually generate
the plots and data of velocity. A chance to work with really skilled
craftsmen, really skilled folks, and then use their tools in very
creative ways, and get a chance to do all that as an end-to-end piece.
A tremendous time.
Then when I was doing the nozzle work, I got to work with the technicians
quite a bit where we did the model installation. I worked with them
hand-in-hand in the facility. Larry Jones was the head technician
there. Again, just a tremendous mentor to me. He was unbelievably
skilled at manufacturing and building, and building up the models
and laying in the pressure lines.
Very methodical, and really, really a skilled technician. I was a
little more impatient. I would just want to go put the stuff in and
go get data, but he would take his time and put it in. I really learned
from him the importance of being methodical and patient and analyzing
and moving forward in doing things. He had the ability—if we
needed a part, he could weld a part for us. We could put another part
in. Another tremendous experience to work hand-in-hand now with the
technician side, not just the engineer side.
I’ll say that the three years I was at Lewis, from 1977 through
1980, were probably fundamental for everything that I’ve done
throughout my NASA career. That experience really gave me an in-depth,
firsthand experience to bridge between the academic world and what
I would need later in my career throughout NASA. I stress the importance
of getting a position where you’re doing the hands-on kind of
stuff; you’re doing test and evaluation. That will really benefit
you in ways you can’t imagine later in your career, even if
that isn’t where you go later in your career.
Ross-Nazzal:
It sounds like such a unique opportunity, as you pointed out. Do you
think that was because it was such a small Center that you had those
opportunities? At JSC it seems like things are pretty segmented, even
back during the Apollo Program.
Gerstenmaier:
I think so. I think because it was a Research Center and it was focused
on research and it was a smaller Center, it gave me a unique opportunity
that I might not have gotten other places. It would not have been
very good, I don’t think, if I would have went directly to JSC.
What I carried to JSC was I could look at a drawing or I could look
at a schematic or operational procedure, and I had a physical understanding
of how it actually worked. I actually knew how hardware was built,
I knew what a data system was and how it actually operated and what
the weaknesses and strengths were. I knew how data was collected.
Those dimensions—although they’re not absolutely necessary
when you’re in an operational environment, I think they really
add another dimension that allows you to understand and operate with
the parameters you’ve got in a very, very different way.
I think you’re right that it was unique in the fact that it
was a time when there wasn’t a lot of new employees there. They
were really interested in helping me learn. That nurturing environment
of spending the time and answering my questions, and then essentially
giving me really challenging assignments. I didn’t feel I was
really ready to go do those assignments, but they didn’t have
much choice. I would get assigned things that I think were probably
more demanding than I was really prepared to go do. It was a great
place.
I think also JSC—where there’s more human life at stake,
or the consequences of a failure have higher consequence, the ability
to take that risk or be exposed to let somebody go do something new
is lessened. There’s more of a formal training, more of a formal
mentoring process than there was at the research facility.
I can’t thank enough the folks I worked with there. I can still
remember all their faces. I know who they all are. They still were
absolutely fundamental in my career. I can’t think of a better
place to start than get a chance to work with those folks.
Ross-Nazzal:
Did you ever get a chance to reach out and brief, say, Rockwell engineers
or some of the folks in the aircraft industry on the research that
you were doing?
Gerstenmaier:
No, I didn’t interface very much with the outside world. The
Rockwell engineers would come in to help us take the data. They would
watch us take the data, but we were a service organization where we
provided them data.
It was also really important at Lewis that you advance your academic
skills and potential, so they had a program where they would bring
professors from the University of Toledo [Ohio] down to Lewis so you
could work on your advanced degree while you were continuing to work
at the Center. I participated in that program, working on a Master’s
degree in mechanical engineering, and I started that in Cleveland.
Ultimately they wanted you to have a PhD [Doctor of Philosophy], because
if you were going to be a researcher, you needed to advance to get
a PhD. That was really on your career path. It wasn’t sufficient
to just have a bachelor’s degree. You needed to advance to a
Master’s, eventually to get a PhD, if you really wanted to be
a world-class researcher. Publishing papers was really important,
but interacting with industry was not all that strong.
In the mixer nozzle world, I’d been told that we needed to be
more cooperative with industry. This was just after the oil crisis
in the ’70s. We were looking for energy-efficient engines. That’s
why we were doing the mixer nozzle program. We were looking in my
group at turbofans. Unducted turbofans were being looked at, high-speed
turbofans. They were really looking for state-of-the-art energy efficiency.
Pratt & Whitney was under contract to do some mixer nozzle work.
They were going to do some laser measurements in the back end of the
nozzle—where I described to you we did the little tiny probes
and put the physical probes in. Pratt & Whitney had a nozzle model
that they wanted to run, get data before they actually put their laser
system in. I’d been told by my bosses that we needed to be more
responsive to industry. We needed to do what they wanted to go do.
We needed to get them data faster than we’d done before.
I listened to all that, then Pratt & Whitney came to us and they
said, “We’d really like you to go put this model in this
central engineering facility. Put our model in, get some data with
the physical probes if you could do that. Then that would help us
be smarter when we go put the lasers in to go get the laser data and
the other information.” I said, “Sure, we can do that.”
They agreed to ship us the model, and then we had to modify the model
to put in the wind tunnel.
It turned out that all my bosses were on vacation during the summer.
I said, “Well heck, I can do this.” Then they brought
the model in. I worked with a draftsman, Oral Mehmed. He helped us
build an interface between the test stand and their new model. We
drew that up and had it manufactured in house, worked with a technician.
We put it in place. From the start of when they shipped us the model
until we actually got them data it was probably two months. Most of
that time was when my bosses were all gone. They had left; there was
one model in the facility. They come back, there’s a Pratt &
Whitney model in there, this whole new data system is in place, this
whole new thing is in place. They’re going like, “Well,
what are you doing?”
I said, “Well, you told me to be more responsive to industry.”
So we turned around this stuff, and we did all this within like two
weeks. Had this whole system in place, and we got all this data for
Pratt & Whitney I think within two months. We got a letter back
from the president of Pratt & Whitney, said he couldn’t
believe that NASA could turn around a project that quickly. Again,
it was just because I didn’t know what was possible, what wasn’t
possible.
I knew who to work with. I knew who to work for, who was critical
to get stuff done. We’d get stuff drawn up. I’d go over
to the machine shop. I would talk to the machinists. I got to know
them really well. Then after we’d get the data I would go back
to the machinists and I would show them the data that we took with
the devices that they built and they designed. That also turned out
to be a really great learning.
Just by showing them how their work then paid off, and how their work
got built into these plots, and how their data was used, I then got
buy-in from these machinists. The next time around when it was time
to get priority in the machine shop, they knew that my stuff was important,
and I would spend time to explain to them afterwards what data we
got. They would give me priority over others, even though there was
maybe a more formal system. They would still machine stuff for what
I needed to get done ahead of others. I learned a way to work with
the community to build the spirit of, “Hey, we can really do
this stuff.” It was just amazing what this team at Lewis would
do to turn things around. That was one example of where we just did
an amazing amount of work in no amount of time.
Pratt & Whitney also wanted to look at—one thing we would
do on the nozzles is they would either end like a straight edge or
you could scallop them. You could cut a corner out, cut a piece out,
and then that changed the flow coming out and it appeared to increase
the efficiency. But nobody knew why because we weren’t sure
how it changed the flow. Pratt & Whitney said, “Could you
modify one of our nozzles?”
I looked at the way we could do that using an electrodischarge machine
to actually machine out the little scallop shape. Then we had to build
essentially a carbon tool. Electrodischarge machining actually erodes
the metal by creating a little arc and burns away the metal in the
shape. This little device erodes after a time. You have to change
the tool out. So then I built an algorithm to actually machine these
carbon tools. We did it on a CAD/CAM [Computer-Aided Design/Computer-Aided
Manufacturing] machine. I built the actual algorithm, I gave it to
the machinists, they built the tools so we could manufacture them
based off of my analog device. We then took the Pratt & Whitney
nozzle and electrodischarge-machined these cuts called scallops all
around their nozzle form. We put it in the tunnel and ran it, and
we did that in about probably a week.
They were totally blown away that we went from a concept to actual
data back in their hands in probably seven days. It was just the fact
that I had the skill that I could write the algorithm to build the
[computer data that drove the cutting machine] algorithm to give to
the technician. He wasn’t familiar with the math and the engineering
to actually build the algorithm to program the machine. I could program
the machine for him, but then I didn’t know how to operate the
machine. We would figure out a way to work together. We practiced,
and then we built this whole process. Again it was just a tremendous
hands-on experience, without a lot of structure. There wasn’t
the formality of, “You need to get approval to go do this. You
need to get sign-off by a person to go do that.”
You were responsible, you were accountable. If we messed up, we messed
up in a big way. This was their only model. If we didn’t machine
it correctly we were in big trouble. So we practiced a bunch of times
and made sure everything was right. We were confident enough that
we could do this. Again, it was taking all the skills from the team
and figuring out a way to put them all together to go accomplish this
stuff.
What a great learning experience that would just pay huge dividends
later in my career. Because building high-performance teams is obviously
really important, how you get folks to work together—all that
is really good. To actually get a chance to experience that firsthand
was just absolutely amazing.
Ross-Nazzal:
You mentioned the importance and value of research at Lewis. Did you
have a chance to publish any papers?
Gerstenmaier:
Yes, published a couple papers from there with some people. They’re
out there, on mixer nozzles. I still have the data book in my office
of the data from Rockwell. I didn’t publish anything associated
with that, but I have all the raw data and I have my original little
test procedures and test plans that are there. It’s humorous
because they’re typed on typewriters and ancient equipment.
It’s an interesting world. But yes, I got to publish a couple
papers and did those things. It was really just an amazing time to
get a chance to work with these folks.
I will tell you I was not as good as the researchers that were there.
I really looked up to them. I could do the work; I could do some of
the physical things. But the real analytical detailed understanding,
they were really, really smart in those areas. They would answer my
questions, but I wasn’t capable of really performing at that
high-level research. So I was more the data taker, more the test taker.
I would do the test piece of it, then it would be compared against
the computational fluid dynamics folks.
We published a couple papers where we’d do blind research, where
they would go analyze say a duct or an inlet or a nozzle without any
knowledge of what the wind tunnel data was. Then I would go take the
wind tunnel data. Then we would publish a comparison paper where we’d
compare what they did with their computational fluid dynamics, what
we actually got from the wind tunnel, and they would be pretty radically
different. They would go back and then they would go change their
model. They would tweak parameters in their model, and then they could
get very good agreement with what the wind tunnel results were.
What we were doing is we were building procedures and processes to
teach the computational fluid dynamics folks how to set their models
up for certain geometry and certain shapes of nozzles and inlets.
We were providing basic information on how you would use this generic
sophisticated computational fluid dynamics tool to be used in the
real world to give you practical results coming out the other side.
Ross-Nazzal:
What was your understanding of CFD software at the time?
Gerstenmaier:
It was pretty much just starting to emerge. So at that time I would
say the true standard or basis was really the wind tunnel test. This
was where it was emerging.
Computational was getting good enough that you could model a lot of
things, but there were still a lot of disconnect between the two.
This was the emergence of computational fluid dynamics. It was neat
to be on the test side because my data was always assumed to be right,
and their data was always assumed to be in error. Then I’d get
to watch them fix and change things back and forth.
There’s a couple comparative papers that are published along
those lines where the results are there. My role was just more or
less doing the physical work, doing more the hands-on stuff, and getting
the actual data for them to compare with their analog results.
Ross-Nazzal:
The tests that you did on the Space Shuttle, did you see any changes
as a result to the vehicle itself that you’re aware of?
Gerstenmaier:
No. Again, there I was predominantly just the data taker. I would
take the data, it would go to Rockwell, and then they would use the
data to confirm models or make changes.
The only time that it came about was after the [Space Shuttle] Columbia
[STS-107] tragedy. When we returned to flight, a large protuberance
air load ramp blew off the Shuttle, a big large piece of foam. That
little ramp was to shield some cable trays on the outside of the external
tank from flow. It was just a foam ramp they put in on the outside.
That broke off.
Then we looked at removing that ramp. I knew from my wind tunnel data
that all the models I ran in the wind tunnel did not have that ramp
on it. So I knew there was a series of data that was available out
in the real world that had all this basic wind tunnel data without
that ramp in place. So I made—I guess it was [The] Boeing [Company]
and Lockheed [Martin Corp.] at the time aware that this data was out
there. All they had to do was go find it.
There was a whole bunch of wind tunnel data without this little thing
that we would like to remove, and it seemed at least that data could
be used to correlate whether it’s acceptable to remove this
extra piece of foam or not. It turned out later we removed that piece
of foam. It was interesting. I didn’t realize that some of the
data that I was taking in the dark ages in the ’70s would be
potentially used later in the 2000s to actually affect an external
tank design.
Ross-Nazzal:
You have a good memory, if you remember that.
Gerstenmaier:
I wasn’t sure. I didn’t remember [if] it was there, but
I had pictures, so I could pull up pictures and go look at the records,
and there was no ramp on the [tank]. I wasn’t positive, but
I could go back and look and confirm it was there. But I knew we ran
those configurations because we were looking specifically at how the
orbiter interacted with the external tank and interacted with the
solid rocket boosters. That was the purpose of this little ramp, was
to shield this cable tray that was on the outside [of the tank from
aerodynamic forces from the other components (solid rocket boosters,
and orbiter)].
Ross-Nazzal:
Curious—did anyone ever share with you the reasons why Lewis
didn’t try to do more on the development side of the Space Shuttle?
Was there any conversation about that while you were there?
Gerstenmaier:
No, I think at that time they looked at themselves as being a research
organization. Very strong roots in the NACA [National Advisory Committee
for Aeronautics] world, in the aeronautics world. They were an Aeronautics
Research Center, so their expertise was in aeronautics.
It was always intriguing because, for example, the supersonic turboprop
stuff, that gave a fairly decent efficiency increase in aircraft.
All the fundamental research was done at NASA Lewis, all the basic
research was done. Then they decided to do a flight test and went
to [NASA] Dryden [Flight Research Center, Edwards, California]. Then
the pictures in all the magazines and all the publicity is about Dryden
flying this new unducted turboprop. It was kind of sad in a way because
I knew all the real work behind that effort actually came out of the
Lewis folks. At the time [they] had spent an inordinate number of
hours of design and redesign and verifying code and analysis and other
pieces, but then they didn’t seem to get any of the glory associated
with the actual flight test. That all went to someone else.
I don’t think we really saw that as a problem. You knew in your
heart what you contributed. You could analyze what you did and where
you helped and where you didn’t help, and whether you got credit
or not out the other side, didn’t really care. The state of
the art got advanced. The new process, new products got out. I think
that’s maybe almost selfishness of the researcher that doesn’t
know exactly how their research is going to be used. It doesn’t
matter to them, it’s just the joy of doing the research. That’s
a great difference between the Centers, when you go to an Ops [Operations]
Center like JSC compared to a Research Center like Lewis. But I don’t
think there was really much consideration that it was there [of Lewis
participating heavily in the Shuttle design].
The other thing that used to be humorous was I would sit in aeronautics
meetings, and we would have our Aeronautics Mission Directorate presentations.
They would always show the Shuttle development wedge in the budgets.
They’d show this chart, and all this money was going to the
Shuttle Program. When that got done [Shuttle development spending],
all that money was going to come back to aeronautics, and then we
[aeronautics and Lewis] were going to get a chance to go do all this
wonderful research [with the “new” budget]. I think every
year I would go to the briefing, and there would be this Shuttle wedge.
We’d talk about the Shuttle wedge, “As soon as the Shuttle
development gets done, man, all this money is coming back to research.”
I don’t think it ever happened. I think the Shuttle wedge never
went away, but we used to see all that all the time.
I think the hardest thing maybe at Lewis was—like I described
to you, all these cases where I was able to do these things working
with these teams was just phenomenal, but it took a lot of self-energy
to get all these people motivated to go do stuff. I think sometimes
they got tired. They really wanted to do more research. They really
wanted to go push in other areas, but the funding just wasn’t
there. So then they would get turned down for projects, they’d
get turned down for programs. They had gone through this huge reduction
in force after Apollo when there was not much money. It was hard even
in the energy-efficient engine world for them, because the aircraft
companies, the propulsion companies were interested in making money
and reducing cost. Energy efficiency was interesting, but the basic
research behind it wasn’t interesting to them. So it was hard
I think for the Lewis team to stay motivated. I felt that a little
bit myself.
We used to joke that the motto was “yesterday’s research
tomorrow.” We used to say that because we couldn’t really
do the research we wanted to go do because the funding wasn’t
there, so we were far more relegated to do maybe more mundane research
than we really wanted. We just didn’t have the funding to push
the state-of-the-art stuff. I think that was hard for the Lewis team.
Also some of the people I worked with, they had worked on supersonic
transport, the big airplane that was supposed to fly supersonically,
and that got canceled. So I think that was a setback to them that
that never went forward. That hurt them a little bit.
They also had done a lot of nuclear propulsion stuff. Some of the
folks that I worked with had done a tremendous amount of nuclear propulsion
stuff, which today is [being talked about starting again]—they
did stuff that was really, really state-of-the-art. That’s what
they wanted to keep doing, but there wasn’t a desire yet in
the aeronautics world to go push that state of the art, because there
wasn’t seen an immediate application for those things.
So they got relegated back to do more near-term, more results-oriented
things and not be doing the cutting-edge stuff. I think there was
a real disappointment for that research community that they didn’t
get a chance to do that state of the art. That’s why the statement
“yesterday’s research tomorrow” comes out. They
were doing research that was important. We would describe it as being
tomorrow’s research, but it wasn’t really the research
that they wanted to go do.
I guess if there was a sad revelation to that, there was that aspect,
that they were doing great work, they could do amazing things, but
[their relevancy was unknown]. By not getting the notoriety associated
with some of the things, I think they got relegated to stay in the
background and do more research.
Ross-Nazzal:
Did that contribute to your decision to move to Houston and work at
JSC?
Gerstenmaier:
Kind of. I kind of got to a point in my career—I thought, “Well,
maybe someday I’d be an astronaut,” or at least I’d
go try to get into the space side of things. I thought, “Well,
if I’m going to do that, maybe I ought to think about going
down to JSC.”
I had applied for the Astronaut Program from Lewis, and I did not
get selected. Then Steve [Stephen G.] Bales in—I guess it was
Guidance, Navigation, [and Control], or maybe Systems Division—was
interviewing. He asked if I wanted to come down to JSC for an interview
to see if I wanted to move from Lewis down to JSC.
He described to me what he had done during Apollo and being in the
[Mission] Control Center. He described being on console and making
these critical calls. He’s an amazing person himself. He made
the call during Apollo to continue on when the computers had a problem,
just a tremendous person. So he describes all these things of what
they’re doing and what my role would be at JSC.
I wasn’t fully aware of what was going on, so then I explained
to him, “Well, I’ve got technicians that sit in the tunnel
and I can look at data, but that’s not that big a deal. There’s
nothing special about all the stuff you’re describing to me.
I can do all that here at Lewis.” That wasn’t received
so well by Steve. Then he told me well I needed to come down to JSC
and see what it’s really like. I think I ended up paying for
myself to fly down to JSC. He took me around and showed me what was
going on. Then I got a chance to see that hey, there’s a lot
more here than just the things that he thought would be important
to me—maybe being on TV, and being in the Control Center, being
part of this big team. I think maybe he thought those would be attractive
to me. That wasn’t so attractive to me. The chance to actually
build procedures and be part of the ground-up, build flight rules
and procedures, and do those things, actually construct things that
would be used in the Shuttle Program was more attractive to me than
the console stuff and the other things that are there.
I didn’t fully understand the breadth of the job, but I thought,
“It’s interesting.” I thought, “Well, I’ll
go down to JSC for a period of time and see what it’s like,
and if it doesn’t work out I’ll go back to Lewis.”
I thought I’d go down to JSC and work for maybe two years and
then go back to Lewis or go someplace else and go do something else.
That was my plan.
I would say that what contributed to it was I realized that if I stayed
at Lewis I could continue to keep doing good work, but it was hard.
I was missing a little bit of seeing how my work fit in the bigger
scheme, and how my work really contributed to moving something forward.
To be part of a more active team that was actually being asked to
go do stuff, whereas I felt like most of the work at Lewis we were
our own champions. We were pushing some of their own work forward,
there wasn’t a real demand going forward. I thought well, I’d
give it a chance and go down to JSC and see what it’s like.
That’s when I made the decision to move from Lewis down to JSC.
I did that in July of 19[80]. That was an interesting time. I moved
to Houston, and I’d been in Ohio most of my life up north. I
like colder weather, I like winter. Then I moved to Houston in July,
and it was like over 100 [degrees Fahrenheit] that entire summer of
1980. July 1980 was when I went down there. That entire summer was
like over 100 for three months, and I thought, “What have I
done.”
It was an amazing place, but the contrast from Lewis was really dramatic.
I go from a very nurturing kind of environment where people are mentoring
you, they’re trying to really move your career in the right
position. Then I go to JSC, and it’s very much more competitive.
It’s really a competition. It’s survival of the fittest.
It’s really a different pace, a different environment, a whole
different feel.
It was a shock to my system, but it was cool because there was a real
sense of urgency. This was before Shuttle had flown. There was a real
drive to get Shuttle flying. Operations were doing a lot of stuff.
I got put in propulsion, which was really good. It was orbital maneuvering
system/reaction control system [OMS/RCS]. I got put into a section
there with some, again, really, really good folks. [N.] Wayne Hale
[Jr.] and Ron [Ronald D.] Dittemore and those folks. It was really
great to get a chance to work with them. They were really experienced
in building procedures and operating systems.
What I did is I tried to find things in my background that were different
than theirs. I had a lot of hardware experience, I understood how
hardware was built. I understood electronics probably better than
they did. I could do software a little bit better than they could.
So I picked areas that they were not interested in or they didn’t
have the same skill sets in, and I focused where I could add to the
team in other areas.
It was a pretty abrupt transition to go from—I would say there
was no one really driving you to get your research paper done by this
date, it was just your own motivation to get it done. To an environment
where this product had to be delivered, you had to be on console with
this procedure or this process or this thing had to be tested in the
simulators by this time. It was a very different pace and different
criticality of work level and activity moving forward. I found that
environment very different than the previous environment, but also
really, really exciting and a really great place to go work.
Ross-Nazzal:
You were around people more your age at that point?
Gerstenmaier:
Yes, there was a lot more people my age, which was different. I had
lost that piece. Then again, it was also amazing that I’m working
with all these heroes from Apollo, people that I’ve read about.
Gene [Eugene F.] Kranz and George [W. S.] Abbey and [Clifford E.]
Charlesworth and Chuck [Charles R.] Lewis. All these flight directors,
all these people that are really legends in spaceflight, and I’m
getting a chance to work with all them and getting to interact with
the astronauts and the Astronaut Office.
It was just a totally, I don’t know, just a great, great place
to be. Just really exciting, really, really good. I go from I think
very nurturing, important, good world to a much more exciting dynamic
world. Still the same underpinnings and the same chance to grow, but
now I’m growing in a totally different dimension, to now grow
in the operations side. Where I got a chance to grow in the research
and engineering side, now I get a chance to potentially grow in the
operations side. It was really, really good. Obviously I ended up
staying there for a long time.
Ross-Nazzal:
What sort of things were you working on with the OMS/RCS?
Gerstenmaier:
We were doing early stuff for Shuttle. We were doing console procedures
and crew procedures. The senior folks were probably Ron and Wayne
and those folks that did the detailed procedures development for the
early Shuttle stuff. We had done all the thermal DTOs [detailed test
objectives] that needed to be done on the early Shuttle flights. Those
are the detailed test objectives where we put the Shuttle in different
orientations to see how it would operate in different thermal environments.
We also did some entry maneuvers to go see how the vehicle would actually
fly. Understanding how the systems would flow, writing malfunction
procedures if there was a leak in the system or this thing didn’t
work correctly—writing all those procedures and processes. They
were all in place to some level, but they were being redefined in
a different way.
Ultimately, preparing to be on console to go monitor operations during
a Shuttle flight. Again great, and a really neat time, when it was
very much the formulation phase of all these things. There wasn’t
a process to get certified to be on console. You were essentially
building all the procedures to be on console. You were training yourself,
teaching yourself to get ready to go be on console and operate on
console. Out of that, I also got exposed to all the JSC basic culture
and philosophy of how you build flight rules, how you keep crews safe,
how you operate, all those things. It was, again, just a tremendous
learning experience prior to the first Shuttle flight.
Ross-Nazzal:
What are your memories of STS-1?
Gerstenmaier:
STS-1, I was on a team in the background doing some thermal stuff.
On STS-1 the orbital maneuvering pods got hit by foam that came off
the tank and knocked some tiles off the orbital maneuvering pods.
We didn’t know what that meant. We didn’t know that the
thermal protection wasn’t there on the OMS pods, because we
didn’t have data. The thermal models were not very good. The
big debate was, “What was going to happen to the front part
of the OMS pod?” It was a graphite epoxy structure. The question
was, “Would we get burnthrough, and would the hot plasma then
go into the OMS pods and ignite all the hypergolic propellants that
were in there and essentially cause loss of the Shuttle?”
We spent a lot of time during the flight analyzing what the best condition
was. Was it better to drain all the propellant out of those tanks
as we could, so if this heating occurred would that be less catastrophic
or less damaging potentially than if we kept all the propellant in
and then there was all this fuel that could ignite and then burn?
We spent a lot of time using fairly crude analytical models and working
with Rockwell and the engineering side to determine what we thought
the best configuration was. The best configuration was to leave all
the propellant in, we thought, because it had some thermal mass. I
just remember the intensity associated with making those decisions
and then working again with a team to try to analyze to the best of
our ability what the entry condition should be for STS-1.
STS-1 comes back and lands with no problem. Nobody knows about any
of that work. We called it a fourth team. What this fourth team did,
they went off on the side and did all this analysis, all this work,
just to see what we could do to put us in the best configuration for
reentry. That’s what I remember about STS-1.
I also remember not knowing what we didn’t know. I wasn’t
overly worried about all this stuff like I would now [know] in hindsight,
looking back [it is scary] what we didn’t know. We didn’t
know exactly how OMS/RCS systems would work. We didn’t know
exactly how propulsion systems would work. We had test data, we had
wind tunnel data, we had model data, we had [NASA] White Sands [Test
Facility, Las Cruces, New Mexico] data. We had an idea, but we never
really got to see the performance of the system until it actually
flew. In today’s world it’d be almost petrifying to think
about all the stuff we didn’t know, and we put crew on this
[first] flight. I didn’t think of that as anything different.
Again, at that point I was pretty much being led by the Apollo group.
If you look at them, what they had done with the Moon, they did all
these things that nobody had ever done before. For them a test flight
with crew was a big deal, but wasn’t as big a deal as Apollo
landing crew on the Moon and doing all these things that had never
been done before. They kind of accepted that, and we just moved forward
with our job. That’s the way it was.
I also remember leading up to STS-1 we had a lot of Shuttle delays,
lots of problems. In hindsight that goes by pretty quickly, but in
foresight it’s just like we were ready to go fly. “When
are we going to go fly?” If I try to put myself back then, there’s
a little bit of anxiety, because Shuttle I think was supposed to fly
in the ’70s. Here it was ’81 before they actually flew.
I’d been at JSC for one full year or more before we actually
went and flew the Shuttle flight. I’d gotten to JSC at the right
time. The group I was going into, they were essentially ready to go
fly when I got there. They had been preparing for STS-1 for three,
four years. They were really anxious. I remember that anxiousness
associated with, “Let’s go fly.”
Ross-Nazzal:
I think the crew said that they were like 110 percent overprepared.
They’d spent so much time in that simulator. After STS-1, what
were you working on? I don’t have you on console in the front
room until STS-4.
Gerstenmaier:
I stayed in the back room. I did OMS/RCS Engineering Officer, then
I was in the back room doing orbit stuff on STS-2 and 3 and those
missions. I was in the back room doing consumables, or doing the back
room job reporting to the front room operator. I was very busy on
all those flights, again building procedures.
I don’t remember exactly the flights, but we learned that a
little bit of residual propellant would stay in the thrusters and
then it would boil off. The way the thrusters determined there was
a leak was they would take the fact that when the propellant leaked
out and it wasn’t combusting, it would actually evaporate and
cause cooling and drop the temperature. When the thruster normally
fired, it left a little bit of residual propellant in the thruster,
and then it would boil off and would chill it down.
The concern was we might get an inadvertent leak indication where
it wasn’t a real leak if you just pulsed at the right frequency.
You’d fire the thruster, then you’d stop and you’d
fire again. Then you could maybe drive that temperature down. I built
a procedure to go actually fire the thrusters at a certain pulse cadence
to try to drive that temperature down and generate a false leak. That
was on one of the early Shuttle flights, I don’t remember which
one it was. It’s the one where I think we had the APU [auxiliary
power unit] problem, and we had to come home earlier. That might have
been STS-3 maybe.
Ross-Nazzal:
I think it was 2.
Gerstenmaier:
Maybe STS-2. It was [Richard H. “Dick”] Truly.
Ross-Nazzal:
Yes, it was Truly and [Joe H.] Engle.
Gerstenmaier:
Engle, so it was 2. I built that procedure to go look at the cooldown
phenomenon of the leak indicators on the OMS/RCS. Again, I didn’t
know exactly what I was doing. We had a normal thruster checkout procedure
just prior to entry where we fired all the thrusters on the Shuttle
to make sure they all worked correctly. I put that little procedure
in to drive these things down to the leak indication in that normal
procedure, because that was an efficiency way to do it.
Then we had the problem with the APU, and they did the test. I’m
thinking like, “Oh, this isn’t going to be really good.
If these things actually all show up leaking, here’s all these
yaw jets they need for entry, and they’re going to have all
these false leaks all over the place. It’s going to look really
terrible.” I didn’t bother to tell anybody I had embedded
all these procedures in the normal thruster checkout thing. I just
remember thinking, “Oh, I sure hope this goes well,” watching
on console. It turns out they got cold, but they didn’t get
cold enough to give the false leak indications and everything was
fine. But, again, I learned that I got to watch what I’m doing
and make sure that others are aware of what I’m doing and where
it fits in the other procedures.
In hindsight, later in my career I see others do that that work for
me now. I have to remember to be nice to them because I did the same
kind of thing where I didn’t fully understand the implications
of what I was doing. I just thought, “Well, this is an efficient
way to get it done.” I didn’t realize that there were
bigger considerations. That was whenever it was, STS-2 or 3. It was
one of the early flights. That’s the kind of stuff I did.
I did a lot of thermal analysis. We had some crossfeed lines where
the propellant flowed between the OMS pods. We predicted one region
to get really cold so we had to build these procedures to actually
flow propellant during the flight to keep them warm. It turns out
that they didn’t get cold. The analysis was wrong. They actually
got colder when we flowed propellant through them. [These are the
type of procedures that I developed.]
I got a chance during that timeframe, even prior to STS-1, to brief
John [W.] Young and Bob [Robert L.] Crippen directly in flight techniques
meetings and tell them what we were doing from an OMS/RCS standpoint.
In hindsight a tremendous exposure to get a chance to interact with
the crew. I remember John Young was an amazing person. He would ask
these questions that appeared to have no basis in anything, and then
I would answer them. Only after I answered about three or four of
his questions would I figure out what the heck he was really driving
at, and I’d go, “Oh man, this is not good.” He was
really, really, really sharp. He just had the intuitive [nature and
wanted to make sure that we knew what we were doing]. I don’t
think he was being devious or trying to trick us, but he was just
making sure that we really knew what we were doing.
He would ask what would appear to be like, “That’s like
a really stupid question.” In reality it was a really important
question that was underpinning a much deeper knowledge that required
you to really understand your stuff to answer in the right way. He
was, in a sense, testing us to see if we knew what we were doing as
we were building procedures for them. It was a tremendous experience
to work with both him and Crippen at that time and get a chance to
work with them on OMS/RCS stuff.
All the stuff that Steve Bales talked about with me when I came down
which I didn’t fully appreciate—I got to actually then
see how it is really cool to get a chance to be interacting with the
flight crew. And explaining to them what you’re doing, and essentially
teaching them your system and how your system operates, and how they’re
going to have to interact with the system. It was, again, just a great,
great learning experience, especially in those formative years when
there weren’t procedures, there weren’t processes.
We were all learning at the same time. I really like that environment
where it’s not so established. It’s a chance to really
learn, and there’s not a process or procedure you absolutely
have to follow. There’s not a console procedure test you have
to take, there’s not an exam yet. You’re teaching yourself
to get prepared to go do this activity moving forward. I really like
that environment. It was a great time to be there for those early
Shuttle flights.
Ross-Nazzal:
When you became a PROP [Propulsion Engineer] then there was no certification
required?
Gerstenmaier:
There was still certification, but it wasn’t formal the way
it is today. You had to do some workbook stuff, but the workbooks
were fairly rudimentary. Some of them were not exactly right. They
were built predominantly to train the crew, so we were taking the
procedures and processes that the crew had used to train. The actual
process and the amount of courses you had to take, that came later
in my career. That wasn’t there at the very beginning.
At the very beginning you were still certified, you still had to sit
on console. They’d give you failures, and you’d be graded
by your peers and by your supervisors. You’d be determined if
you were sufficient to go on console or not, but it wasn’t as
formally documented with the set of rigorous classes to take and procedures
to take. There were some, but they weren’t nearly the rigor
that came later. You would do some stuff in the trainers in Building
5 to see systems. You would do some stuff with the workbooks and other
things, but most of the learning was actually from building the procedures
yourself, building your own console procedures in the simulators.
Also a tremendous learning experience, because you got a chance to
go over to the simulators. As you’re building a procedure, you’re
really learning how things work. You’re learning also how the
simulator works, how the simulator doesn’t work, where it models
the real world, where it doesn’t model the real world. That
was good.
Ross-Nazzal:
You were on console in the main room for STS-4, which was the last
OFT [orbital flight test] flight. What are your memories of that mission
and the OMS/RCS system?
Gerstenmaier:
It’s interesting. Maybe in hindsight people think of orbital
flight test as being some demarcation of “Shuttle was then operational.”
I don’t see it that way at all. They may have said that on the
outside, but internally we were still learning. We were still experimenting
with systems; we were still pushing the Shuttle. There was a lot to
do.
I don’t see a differentiation of much between STS-4 and the
[later flights]. It was more how we started using the Shuttle. Later
on, like on I think STS-7 we did some rendezvous prox [proximity]
ops [operations] stuff. I got to develop a lot of the rendezvous prox
ops stuff. It was interesting. I interacted with the GNC and the FDOs,
the Flight Dynamics Officers. Then we were building procedures on
how to use the Shuttle OMS/RCS systems to actually maneuver the Shuttle
to accomplish an objective, to rendezvous with some target, to do
some activity.
My role was more how you use physical hardware to accomplish these
other goals, but then I got to learn rendezvous prox ops and bingo
numbers and all that stuff. All those early procedures development
and stable orbit rendezvous—I got to work with the Mission Planning
and Analysis folks who did a lot of the work behind the scenes—almost
like what I had done in Cleveland—take their research and figure
out a way to actually apply it to flight. How you actually turn that
into a flight procedure that a crew goes off and executes, and how
do you do this in the best way that ensures mission success.
I didn’t see STS-4 as anything specific. If I go back and I
look at the crews, and maybe I go look at what payloads were on there
and what the mission objectives are I could tell you where they are.
But somehow those are all lost in my memory somewhere. I remember
some crews, I remember some activities more than others, but I don’t
remember any real specific notable things about that. Learning to
operate in the front room was different, being on console was different,
interacting with the flight directors was different. The training
level was fairly intense.
I liked orbit a little bit better than ascent/entry. I did orbit first.
The reason I liked orbit a little bit better is it wasn’t as
structured. You had a chance to actually change things. The time constant
before something happened that was bad was longer, so you could be
more innovative, a little bit more creative. If a payload didn’t
deploy or something happened that was different, you had time to go
work things.
Our predominant job was to make sure that the amount of propellant
we had for this mission was protected so the crew could do a safe
reentry and had enough propellant to come in and land. That was our
job on orbit, was to make sure we preserved that propellant for later
uses in the mission. We had pretty sophisticated ways we calculated
that, and how we monitored burn performance on orbit to see if the
thrusters were using the right amount of propellant, and we were keeping
propellant balanced between the forward and the aft and prepared for
contingencies to come home early if we needed to. That was the orbit
role. You could be more innovative. You could be more creative.
Ascent/entry on OMS/RCS you had to be really quick. You didn’t
have much time when a failure occurred to when you had to make a call,
so there was no chance for creativity. You needed to know exactly
what was going on in terms of a leak, what was happening in the propellant
system. You needed to make a split-second call. That was life or death
for the crew whether that call was right or not, so that was really,
really intense.
In that phase of my training on console operations, I really wanted
to simulate as much as I could on console. I would want to sim at
least three times a week to keep at that high proficiency level, because
it had to be just second nature to you. You had to use the products,
the tools. You needed to know exactly what to go do. You didn’t
have a chance to go, “Okay, which book is that in? Should I
go look at this other book?” There was no choice.
That was a very much more intense phase. That’s the big change,
going from orbit to the ascent/entry phase. Entry for OMS/RCS was
really, really critical too. The interactions with the Guidance, Navigation,
and Control folks was really important. A very dynamic, really critical
time to really monitor systems. You really needed to know your stuff.
I would say probably the most senior folks were in ascent and entry.
You typically started on orbit, and then you moved to ascent/entry.
I remember much more the transition from orbit to ascent/entry than
I do the transition from maybe back room to front room, or even the
OFT demarcation.
I don’t really see STS-4 any different than STS-5 or 6 or 7.
I see those really as a continuum across the Shuttle spectrum. The
Shuttle could do more. We did more stuff with the Shuttle, but we
were still doing DTOs. We were still doing thermal stuff; we were
still checking things out.
Ross-Nazzal:
I did notice when I looking at STS-5 and some of the other missions—when
[Space Shuttle] Discovery came on board—there was still a lot
of testing going on. I was kind of surprised to see that in the press
kits. All the tests that you were doing on the systems, I thought
you knew quite a bit about those systems. So you were constantly learning,
every mission?
Gerstenmaier:
Yes, every mission. We would do certain thermal DTOs, and they’d
be more stressful than the other ones. I remember we exposed one side
of the Shuttle to high temperatures for an extended period of time
towards the Sun, and it actually bowed the Shuttle enough that the
cargo bay doors would not go closed. So then we had to go reorient
to a different attitude to unbow the Shuttle so the doors would go
closed.
We were really learning what the vehicle could do and couldn’t
do in various applications. Where our thrusters got too hot, where
things got too warm for your systems, you really started learning
how your system really performed. Then your job was to document that,
write that down. Then the next set of folks or a mission came up where
you wanted to do something more demanding, you knew how the vehicle
actually operated and flew. I think we were in flight test all the
way through the end of the Shuttle Program. In the outside world it
may have got portrayed we went operational. I don’t believe
we ever went operational. We were always in some level of flight test.
Ross-Nazzal:
You mentioned how dynamic ascent and entry were, that you really had
to know your system. Were there ever any moments where you really
had to recall that information that you remember?
Gerstenmaier:
Yes. One of the fairly early ones there was a reentry, and we lost
the relay box that configures power to the valves. We had this thing
called the OMS/RCS slide rule. It was a piece of paper, and you would
slide it back and forth. Depending on which power bus went down, it
would show which valves you’d lose telemetry from, which pressure
transducers. You could use this slide rule to figure out fairly quickly
which power bus had failed right off the bat.
I just remember being on console during an entry and one of the circuit
breakers or these power controllers failed. Just by looking at essentially
the lights on the console I knew exactly which switch it was, exactly
where the power controller was, and exactly what the crew needed to
do. I remember making a call to the flight director to have the crew
configure the switch, and it was exactly the right switch.
It was almost second nature. I had trained so much that there wasn’t
really a whole lot of cognitive thought. It was just visual recognition.
“These lights are on. This is the error. This is more than likely
one of these devices. This is the device that it probably is. Here’s
the call, go.”
It was remarkable to me. It was like a high performance athlete when
you set the world record or you set the personal record. Sometimes
when that happens you just feel like you’re in the groove and
things are clicking right along. That was exactly the feeling I had
afterwards. It was just like yes, that’s exactly where all those
hundreds of hours of training went in. I got a chance to actually
see the scenario and do exactly what I was trained to go do. It wasn’t
a big deal. It was just what you’re supposed to go do. It gave
me encouragement that what I was doing and how I was learning was
a positive way. That’s why I wanted to keep that level of proficiency
up.
On [the ascent simulations] it was hard. You would get to orbit with
the crew [using propellant from the] OMS/RCS, and sometimes you would
have used all the propellant to get to orbit such that the crew could
not come home. The crew wouldn’t know that they were actually
lost, you actually killed the crew because you didn’t have enough
propellant on board to return. We’d recycle [the simulator]
back around [for another simulated ascent]. Not anybody would probably
know in the Control Center [what] you just [did]—the good news
is we got the crew on orbit, the bad news is they’re going to
die because they don’t have enough propellant to get home. You
would know that as an ascent/entry flight controller on the PROP side,
and then you’d have to deal with that. You’d have to deal
with the fact that I just killed the crew. I wouldn’t necessarily
vocalize that to everybody. But I knew it in my heart, and I’d
go, “Crap.” Then you recycle again, you get two minutes.
Now you’re back again doing another ascent run.
That’s how serious it was and what the calls were and the data
you were making. You personally had that feedback of how many times
you killed the crew. You knew how good you were, how good you weren’t,
and you had to live with that, and then know you were really prepared.
There was a lot of self-evaluation to make sure that when you were
on console—I didn’t care if I was certified or not—I
wanted to make sure that I was at the right proficiency level that
I was comfortable with what I was about ready to go do. That I was
the best person to be in that slot to go do that. And if I didn’t
feel I was there, I would say to somebody, “It’s not time
for me. Somebody else go figure out a way.” Even though I may
be certified, I wanted that proficiency level. That was a very intense
activity, a very intense period.
But again, as you look back, all those things prepare you for later
things in life. I still carry that same thing today when I sign flight
readiness review statements. I sign a flight readiness review statement
with the same seriousness that I [had] on console, knowing that my
call will cause the crew to either live or die. My evaluation of this
team that we’re ready to go fly is just as serious and just
as important as it was when I was back on console. That same seriousness
associated with your responsibilities is present in both cases. Some
people might see that as paralyzing or stressful. I don’t, it’s
life. You do it every day in your own life. You don’t get it
portrayed to you as starkly as I described to you, but it’s
there. I don’t see this as a big thing, but then that responsibility
is huge. That individual accountability is really, really, really
important. It needs to be there.
Ross-Nazzal:
When you walk into the MOCR [Mission Operations Control Room] today—they’re
going to restore it as you know—you see the mission plaques.
Did you ever have the opportunity to hang a mission plaque at the
end of a mission?
Gerstenmaier:
No, I never hung a mission plaque. But yes, I see them and I think
about the teams. That’s the other thing that’s a lot of
fun about our business is the team activity, that you’re really
part of this bigger team. None of us can accomplish these things we’re
doing in human spaceflight without just a huge team.
That’s another wonderful aspect I think of this job. I think
you know in your heart you have to be prepared, just like I described
to you, to that level of performance. I expect every team member on
that team to be at that same level, and that’s when you really
achieve amazing things. Whoever hangs that plaque it’s cool
because they did their piece and they got in the spotlight, but underneath
them are all these other folks that did the more mundane routine stuff
that was probably just as critical as the person hanging the plaque.
But it’s still cool. The need for everybody to work together
and play flat out, to tell folks what you know and what you don’t
know, to tell folks what you’re uncertain of, what you’re
not sure of—that’s just as important as appearing that
you know everything, appearing you know this, you know that.
You’ve got to be not afraid of saying, “Hey look, today
isn’t my greatest day. I’m tired today. I’m not
performing the way I should. You watch what I’m doing today,
even more than usual. Make sure that when I’m on console and
making these calls.” I’ll tell my back room folks, “Today
isn’t the day. For whatever reason it just isn’t quite
the level. So you double-, triple-, quadruple-check me, and make doggone
sure we’re doing the right thing.”
Exposing that vulnerability to others I think helps make the team
stronger because they know when you’re not there. You build
that team cohesion that you’re there. Then you know that if
somebody else isn’t there, “Okay, I’ll cover for
you today. I’ll help you here.” That’s a cool thing
in human spaceflight. That’s one of the many things, but that’s
one of the things I think is really phenomenal.
Ross-Nazzal:
In Gemini and Apollo and even in Mercury you hear all these anecdotes,
these stories from the flight controllers. They liked to play a lot
of pranks on each other. Was that something that was still common
during the Shuttle period?
Gerstenmaier:
Yes, I think we did that quite a bit. Yes, we did stuff. We had pneumatic
tubes, which I’m sure you heard about. We would put strange
objects in there, like Coke cans, and then they would clog up the
whole pneumatic tube system. We passed paper around through pneumatic
tubes, and we put a frog in there once. We did all kinds of little
things back and forth. You’d do stuff to tweak each other.
After simulations we’d do a party or celebration afterwards.
Those were a good chance to just kick back and relieve stress a little
bit and talk to folks. They were also a chance to informally debrief
what was going on, what happened, what didn’t happen. I remember
a couple events at the Gilruth Center.
I remember one in particular where they had failed a temperature transducer
in one of the vernier jets. We had been playing around with the ability
to change the code where we actually went into the code, and we did
an [assembly language] code change to ignore that pressure transducer.
It was a rewrite of the software.
We were in the simulation, and in the simulator the sim sup [simulation
supervisor] gave us that failure. I thought “Oh, we’ll
try this thing.” So we tried this procedure, and we changed
the software code, did everything. It looked like it worked right.
The simulator run got done. Then I decided, “Well, we ought
to test it to see if it really works,” so I asked the sim folks
to lower the temperature down like a leak and see if it would annunciate
the leak properly. They lowered the temperature down and it did not
annunciate the leak properly. So the procedure didn’t work.
I remember the post-event at the Gilruth Center where we’re
all out drinking beer and [eating] pizza and having a good time. I
remember Gene Kranz and Steve Bales coming to me and just lecturing
the heck out of me because I should have never taken a procedure that
I wasn’t confident in and uplinked it to the vehicle, even though
it was a simulation, because that wasn’t the time to learn.
What you were supposed to do on console was exactly what you were
going to do on flight, and you don’t get creative at all on
console when you’re doing simulations. What you do in simulations
is exactly what you do in flight. I must have got lectured by them
the entire evening for this thing. I felt really bad, and I kind of
disagreed with them because I’m kind of wired to learn stuff.
But I was not going to argue with them. I was not going to win. That
still was a good learning experience.
I don’t think without that after-event party and that atmosphere
they would have found the time to really grill me, or if they would
have grilled me in the office that might have been taken a totally
different way. They threatened to remove me off console and a bunch
of other stuff which was interesting, but I was pretty tough. It was
okay.
It was good in the fact that it really drove home the seriousness
of the simulation, so I think it tempered my thinking. When I’m
going to do something in a simulation, just like I described to you
before, it is really life or death. The things I’m doing, I
better think, “Okay, I need to treat the simulation as real.
I do not need to treat the simulation as something that is just a
video game or just something to participate in.” That stress
level that I feel during simulations, it better be the same stress
level I feel in flight. That’s what they were effectively trying
to tell me to go do. …
I think sometimes you think of these periods of when you go do pranks
or you do things off to the side as wasted time. I think there’s
also a chance there that they can be another learning experience,
that it actually helps you reinforce learning and other processes
going forward. They’re just as important I think sometimes as
the actual activities, and maybe we don’t take enough time today
to do some of those things, to just go back and play a little bit
or experiment a little bit or try something off to the side in a less
formal environment. I think those things were important, but again
I think you needed that. You needed some way to blow off steam or
do things different. As you know when the old days of chili cook-offs
were a big thing, and they still are a pretty big thing.
Ross-Nazzal:
They still are, yes.
Gerstenmaier:
They were probably another level that was even more inappropriate
than they are today. They were still cool, and it was a chance for
us to get together. I think the team spirit carried more from not
only on-console and work, but the proximity of folks in the Houston
area and the Clear Lake area would allow you to do stuff with your
coworkers after hours and work. I think that’s another piece
of the team building that’s really important. Getting a chance
to work with all these folks not only at the seriousness of work but
also in other things in the community.
Ross-Nazzal:
That’s something else. The flight directors from the Apollo
period, they had a specific bar that they would go to after a simulation
or during a splashdown party. Did you guys have a location or place
that you would hang out?
Gerstenmaier:
We did a lot of things after sims and flights at the Gilruth Center,
so the Gilruth Center was a place. There were a couple places where
in town people would go. Bill and Marie’s [Ice House] and some
other places, the Outpost [Tavern]. There were places where the teams
would get together periodically and they would move around. I don’t
think we had any one in particular. Some flight directors would order
burritos from a certain place for the whole team, and we would eat
burritos.
There was that sense of doing things together, and certain locations
to go together. It’s maybe the flight test mentality, the test
pilot mentality, of going someplace to just kick back and do some
things that you wouldn’t normally do. Get a chance also to tweak
each other a little bit and do pranks on each other. We used to do
that periodically even in the building with each other.
Ross-Nazzal:
Were you over in Building 4?
Gerstenmaier:
Yes. I remember when Dick Truly flew, they recycled a bunch of his
official astronaut pictures, so they put them out in the hall in a
stack to be disposed of. We took his pictures—and he was in
an EVA [extravehicular activity] suit—and we took his head and
his arms. We took all the clocks, and where the arms were on the clocks
we put his arms from the spacesuit on, and we put his head in the
middle. We changed all the clocks in Building 4 to have Dick Truly’s
head and arms on every clock in Building 4. I remember that as being
pretty humorous when Dick came in the next day. Every meeting he went
to, there he was on the wall on the clock with his arms and his head,
courtesy of the pictures they were throwing away from upstairs. We
did silly things like that.
Ross-Nazzal:
I think we’re coming close to the end of our time today, so
unless there’s anything else you’d like to talk about
this might be a good stopping point.
Gerstenmaier:
I think that’s good.
Ross-Nazzal:
Thank you very much.
Gerstenmaier:
Good, thank you. Thanks for doing this.
[End
of interview]
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