Steve Johnson Interviews – Apollo/Saturn Program

Date 1

NASA MSFC Oral History Interview

Steve Johnson Interviews – Apollo/Saturn Program

Ron Tepool

Interviewed by Steve Johnson

Location – Huntsville, Alabama – Date

Steve Johnson: I am talking with Ron Tepool, who worked at Marshall Space Flight 

Center from 1963 through January 1, 2012. He worked on the Saturn and the space 

shuttle, among other things. Ron, would you talk about your education? What prepared 

you to be in the space program?

Ron Tepool: My dad was a builder in Indiana and I used to help him. We were 

building a house one day, and it was a really nice house, and I asked, “What does this 

guy do? This is a nice house. How can he afford it?” He said, “He is an engineer.” I 

decided to be an engineer. (Laughs) I went to the University of Evansville, got a degree 

in mechanical engineering. I went there on a scholarship. I played football at the 

University of Evansville. Some of my classmates were in the co-op [Cooperative] 

program here at Marshall Space Flight Center. I came down one day with J.C. Agnew 

[Name/Spelling?] to Marshall Space Flight Center and interviewed with the Test Lab. I 

then interviewed for a whole quarter when I was graduating from college and decided 

to come here and go to work. 
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Johnson: What kind of engineer are you?

Tepool: Mechanical.

Johnson: A mechanical engineer and you went to work as a test engineer. Let us talk 

about the challenges for a test engineer in the development of the Saturn V. You were 

responsible for testing the main engines, am I right?

Tepool: Testing engines for Saturn. It was the F-1 engine. We had two test stands here 

at Marshall Space Flight Center that were configured from the propellant tanks out 

exactly like the vehicle. They had vehicle suction lines, flight weight prevalves, all the 

hardware that went to the tank was exactly the same. We investigated pogo.

Johnson: Pogo, that is the fuel moving up and down and causing problems.

Tepool: Right, pressure oscillations in the feed system that generate a pulse that is 

equivalent to the natural frequency of an astronaut’s insides. They cannot stand to go 

through this vibration, so you have to somehow dampen that out. We worked that. 

Basically, we were doing the development work for F-1 engines. The first three S-IC 

flight stages and the test stages were all built here at Marshall in the Apollo Program. 
Steve Johnson Interviews – Apollo/Saturn Program

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The T-bird, the dynamic bird, the structural bird, flight vehicle -1, -2, and -3 were all 

built here at Marshall. The T-bird, structural bird, and dynamic bird had fake engines 

on them for dynamic tests, for structural tests, things like that. A test bird had real 

engines. All those engines were developed by North American Aviation, Rocketdyne 

Division along with NASA [National Aeronautics and Space Administration]. They 

would ship them in here, we would fire them. We had to adjust the gimbal, the thrust, 

within sixth-thousandths of the center of the gimbal block. To do that, we would set the 

gimbal actuators on the engines, we would fire them, and then we would adjust those 

actuators and fire them again to prove that we were going sixty-thousandths of the 

center of the gimbal block. With the five engines, when you were gimbaling, you had to 

be able to point them exactly in the right direction to control the vehicle. Then we 

would put them on flight stages, we would fire the flight stage, and then ship it by 

barge to the Cape [Canaveral, Florida].

Johnson: The engines had been fired before they were shipped to the Cape?

Tepool: Yes, every stage that we have ever flown a man on, everyone, including the 

shuttle, have been tested on the ground, hot-fired. 
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Johnson: As a test engineer, obviously testing is what you do. Were there challenges to 

testing? You just said one of the challenges, but did you want stuff to go wrong, so to 

speak, so you would know?

Tepool: You do not want something to go wrong.

Johnson: No, but if something goes wrong, you want it to go wrong on the ground.

Tepool: That is exactly right. That is why you test, to wring out the problems. Some of 

them are very hard. Problems you would encounter due to zero g [Gravity] or altitude, 

they are hard to test for on the ground. Almost every other problem you can wring out 

on the ground, as far as your turbomachinery, how good it is, how tough it is, what its 

endurance is, how long things will last when you subject them to that kind of 

environment. Most everything you can test on the ground, unless it has to do with 

vacuum, being in space. You cannot check the flight regime because you have to hold it 

down to test it. We did test fly the vehicles before we put men on them, the total flight, 

but basically that is a test. That is what we did.
Steve Johnson Interviews – Apollo/Saturn Program

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Johnson: For the Saturn V engines in the Saturn V Program, generally speaking, were 

they tough to make work correctly, or was the design so good that things did not 

happen?

Tepool: No, we had problems with rough combustion. To solve that problem. We put 

baffles on the injector. Then we would bomb it, make it go rough, and then make sure 

those baffles would dampen it out. 

Johnson: When you say bomb it, you actually exploded something during the engine 

firing?

Tepool: Right, you screw a thing that looks like a shotgun shell in there. You crank the 

engine up, and then you electrically trigger that shotgun shell-like and blow it up. It 

makes it go rough for a little bit. The baffles on the injector would dampen it out. We 

had rough combustion. We had LOX [Liquid Oxygen] pump problems. We have always 

had LOX pump problems (Laughs), but on the Saturn on the F-1 engine, we had LOX 

pump problems. We had three development stands at Edwards [Air Force Base]. We 

had a development stand at Santa Susana [Field Laboratory]. We had two development 

stands here at Marshall. We probably blew up thirty engines.
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Johnson Caused them to explode?

Tepool: Not on purpose. They exploded or a LOX pump went bad and they would 

burn up.

Johnson: You were testing them to their maximum limits. 

Tepool: Right, we were testing them to max limits, gimbaling them hard, and things 

like that. That is the way you learn. When we started in shuttle, we had to go through 

that same type of thing.

Johnson: How many test firings do you figure you were a part of in the Saturn 

Program?

Tepool: I probably conducted 100, 150 tests myself. Then I became a branch chief and a 

division chief, and my people did that. When I was doing the test engineering, counting 

down and stuff, probably 100 tests or so.

Johnson: How exciting is a test firing? Those test stands at Marshall, just from the 

sound of what you did, were used a lot to fire engines. How exciting was that?
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Tepool: It was very exciting. In fact, an F-1 engine burns 42,000 gallons a minute of 

propellant, seventeen of fuel and twenty-five of LOX. That is a lot of propellant flowing 

per minute.

Johnson: How long might you test one?

Tepool: They run for 150 seconds and generate 1.5 million pounds of thrust each. When 

we fired the S-IC stage of the Saturn V, we generate 7.5 million pounds of thrust, and 

we had to hold it on the ground while we were doing it. 

Johnson: You are talking about the test in 1965 when you sort of rocked the whole town 

when you tested all the main engines?

Tepool: Right.

Johnson: What was that like? Anybody who lived in Huntsville in 1965 knew the town 

rattled, but what was it like being as close as I am sure you were?

Tepool: It depends. I was the engine man on the S-IC-T. They were my five engines and 

I had a group of technicians. The first test we ran on the S-IC-T we had all five engines 
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installed, but we were only going to start the center engine. Harry Johnstone was 

counting it down, Bob Sala [Name/Spelling?] was there, my boss was [J.H.] Joe Lundy, 

Wernher von Braun was there, James Webb was there, they were all in the control 

room. I was on the periscope looking at the main engines. Johnstone says, “Tepool, you 

know that purge ring you use?” I said, ”Yes.” He said, “I am not going to turn it on 

when we start.”

Johnson: What is a purge ring?

Tepool: On an F-1, it was a hyperbolic start, which is when you push the propellant, 

when it touches air, it turns to fire. It is a hyperbolic start. When that hyperbol 

[Spelling?] would go into that chamber, immediately a big fire would come rolling out 

of the chamber and it would go up the sides of the engine, all the way up past the 

gimbal block, twenty, thirty feet in the air. It engulfed the engine. We built purge rings 

out of one inch stainless steel tubing, which had 1080 eighth-inch holes in it, fed it with 

3000 psi [Pounds per Square Inch] GN2 [Gaseous Nitrogen], and we would turn it on 

right before start. When that hyperbol would break, it looked like the engine was firing. 

That inert gas purge was holding the fire under the chamber. 
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Because we were only firing the center engine, the first time we had ever fired this 

stage, it had never been fired before, it was a brand new stage, it was the T-bird, the test 

bird. They were only going to tank less than a quarter of a tank of propellant, of LOX 

and RP-1 [Highly Refined form of Kerosene]. By doing that, that means your 

pressurization gas is coming in to pressurize those two tanks. You have a lot of volume 

to fill up because you have a lot of ullage. He was afraid he was going to run short on 

purge gas, GN2. He said, “I am not going to turn it on.” I said, “Okay.” He said, “If you 

need it, you call for it.” “Okay.” He counted it down.

In the bottom of the S-IC stage where the five engines are hanging is two-inch thick 

asbestos in squares about two by two sheets that are bolted to the bottom. That is a heat 

shield. When you go up in altitude, the fire goes up there, and it keeps that metal from 

melting and tearing up the bird. Somebody had the bright idea that that asbestos is real 

porous and it would soak up moisture. They said we ought to shrink-wrap that so that 

it does not soak up moisture. Any moisture we had, we have to carry with us and that is 

weight. It was wrapped in a blue shrink wrap. You have seen these shrink-wrap 

packages when you buy something at the drug store. When we started, the fire came 

out of the bottom of the engine, rolled up, hit that blue shrink wrap, which I did not 

know what was going on, but it went white hot, so I cut it. I cut the very first test.
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Johnson: You turned it off.

Tepool: I turned it off. I clicked my cut button. My boss comes walking in, flying down 

through there, “Who cut that test?” I said, “I did, but I will be ready to go in an hour.” I 

took off. I walked out of the control room and all my support people were sitting out in 

the hall and they were giving me a hard time because they knew I cut it. I went out to 

the test stand, rolled the deck in. When you cut the engine, it ends up full of fuel. I 

drained the fuel out, put ethaline glycol in it, which is like antifreeze, in the chamber so 

you do not get a pulse shock when you start, put two new squibs in the gg, put a new 

hyperbol in the combustion chamber, rolled the deck out, and went back up the stand.

We fired again. 

It ran seven milliseconds longer than it did the first time because we had a program that 

said if one main fuel valve is open before the other one gets closed, it will but 

automatically because it was going to go unstable. It was a broken dish pan that caused 

that. We gave up that night. We went to the Officer’s Club for a party. Since that was 

the first firing, a lot of the contractors were in town and were having a party at the 

Officer’s Club. Dr. von Braun comes and gets me. The movie of the day was Goldfinger. 

He took me around to every corporate table and introduces me as the guy with the 

golden thumb of the test. That was my experience at the very first S-IC test at Marshall.
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Johnson: Were test firings expensive?

Tepool: Oh, yes. It cost us another hour and a half that day. 

Johnson: In any case, if you would have left it on, it would have.

Tepool: It would have been alright. It would not have cost us that hour and a half. 

Johnson: You did not turn other tests off. This testing and looking for problems was a 

constant.

Tepool: Yes. People kind of treat things with a “if it made it through Test Lab, it was 

going to be fine” (Laughs) because sometimes you had to climb on it, you would have 

to do things you would not normally do to a flight vehicle. If it happened to your test 

vehicle, then. All flight engines were static fired too before they were ever.

Johnson: I think what you are saying is you were pretty rough with it on purpose. You 

did not want kid gloves there. You wanted it to show it would do what it was supposed 

to do. Did you have to develop any new tools or come up with any new materials 

during this test process?
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Tepool: Our materials Lab came up with a lot of new materials during the test process.

Johnson: Your job was to test the new materials.

Tepool: Right. We had a group that tested the materials. I was in propulsion tests. We 

had a materials test group, we had a cryogenic test group, we had a components test 

group, we had a systems test group. I was in the propulsion systems test group. We 

tested engines, stages, bigger things. Of course, when we ran out of that, we would go 

help the component people or whatever. Our techs [Technicians], they were always 

making new tools. The Snap-on man came every week.

Johnson: Snap-on, like tools for automobiles?

Tepool: Right, the Snap-on guy, he came every week in his big truck full of tools and 

the techs would go get what they needed. If you are up on a test stand, you are seven, 

ten stories up, and you drop your ratchet, you cannot afford for a guy to go down the 

elevator, go into the bucket, look all over until he finds his ratchet, and come back to 

work. You just get another one and go to work. The Snap-on man came. Then there 

were a lot of jobs where the tooling back in the plant that built it was great, but if you 
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had to take it apart out on the test stand, it was tough. The techs were really good at 

making tools. They could modify an existing tool or go make one from scratch that 

would get the job done, whatever you had to do. We had a lot of that.

Johnson: I have heard stories of Dr. von Braun actually visiting a site or test stand and 

somebody saying they needed a tool and he would sometimes hand then the tools. Did 

you ever see anything like that?

Tepool: I have never seen that. Several times, he came to the test sites where I was a test 

engineer and I would tour him through them. 

Johnson: How heavily involved was he in what you guys were doing, these constant 

test firings and stressing the equipment? How involved was he in what you were 

doing?

Tepool: Engineering-wise, not involved at all, but he was on his managers big time to 

get the job done, wring out the problems. If you needed something, do not be afraid to 

ask. I will go fight for the money. That kind of thing. He was at Headquarters a lot 

trying to get funds to do other things. A lot more testing could have been done, which 

would have raised your confidence level, but there was not enough money.
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Johnson: Many people during the Saturn days would say money was not a problem.

Tepool: It was a problem. It was not a problem like it is now. It is always a problem, but 

not as bad as it is now or was in the shuttle years or the following years.

Johnson: Even in the Saturn V years, you had to worry about how much money you 

were spending on testing?

Tepool: You had to make sure you had enough to go do what you wanted to do. If you 

did not, you had to go ask for it. Then somebody else either had to not do something. 

There is only so much money allotted each year and you have to stay within those 

allotments to get the job done.

Johnson: You said you could have done more testing to have more confidence. In 

general, when we finally got to the point of launching Saturn Vs and putting men 

onboard, as a test engineer, if people asked you what you thought, would you say this 

thing is going to go great? Were you at that point?

Tepool: Yes, for the Saturn V, not for Skylab. We ran a test on Skylab that said it was 

going to come apart when we launched it, and it did.
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Johnson: When we lost the cap.

Tepool: The panel, right. 

Johnson: You knew Skylab was a problem. In general, up until that mission, by the time 

the Saturn Vs flew, you were confident?

Tepool: We were confident we would make it 150 seconds. Our job was to get it up 

there. We did not realize what JSC [Johnson Space Center] had in the Command 

Module and Service Module. We just had the first three stages to get them up there. We 

were confident we could do that. We had one J-2 cut off in flight where we burned up 

and ASI line, I think.

Johnson: ASI, what does that stand for?

Tepool: Augmented Spark Ignitor line. It was a propellant feed line for the Augmented 

Spark Ignitor. 

Johnson: If it would have been up to you, if they had said, “Ron, what would you like 

to do,” would you have tested more before you flew?
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Tepool: Not in Saturn.

Johnson: What was the pace of work like during the Saturn days for test engineers?

Tepool: Let me give you an example. When I came to work here as a test engineer, the 

current minimum wage is about four times what a test engineer made when I came to 

work here, $2.56 an hour.

Johnson: That is what you were making to test the most powerful rocket ever 

launched?

Tepool: When I first came here, right, in 1963. I think the minimum wage now is about 

ten dollars, eight dollars. I was married and I had a child on the way. I bought a house 

here. I did not make enough money to pay the payments. Hunter and Mitchell is who I 

bought it from. They told me to make the construction loan payments and when I got a 

raise to come see them and they would close the loan. Go ahead and move in. I did. We 

worked enough overtime, we were working ten, twelve hours a days, and overtime on 

Saturdays. We rarely worked Sundays unless we really had to. We made enough 

money to do alright. 
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Johnson: To make your house payment?

Tepool: Right.

Johnson: What about the work environment? You are working all these extra hours, 

sometimes Saturdays, sometimes even Sunday. Was it fun? Did you not want to go in?

Tepool: No, we lived a dream here. We had a great work environment. We lived the 

dream up until [Barack] Obama came along. 

Johnson: As a test engineer, were there dead ends in what you guys did?

Tepool: Yes. When we got done with Apollo, they started laying everybody off. They 

loaded up trailer truck loads of tools and hauled them out to these technical centers and 

schools. The state came in and got hundreds and hundreds of trailer truck loads of steel 

and aluminum ingots and took it away. We went to work on cold gasification.

Johnson: This is at NASA?
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Tepool: At NASA at Marshall Space Flight Center after the Apollo Program. We got 

done, it was not after the Apollo Program.

Johnson: You were to the point where testing engines was over. 

Tepool: We were done by the time they went to the Moon. We were done at Marshall. 

Johnson: You had to do something else.

Tepool: We had to do something. Of course, when we got done testing the engines, we 

worked on the Lunar Rovers and the Apollo Telescope Mount, things like that. 

Johnson: You were still doing testing?

Tepool: Right. We even did testing for cold gasification, gas refrigeration, those kinds of 

things, and then shuttle came along. Shuttle did not really get tooled up until about 

1974. 

Johnson: That was just before Skylab?
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Tepool: Skylab was ending about that time. Shuttle was up and going when Skylab 

crashed, when they finally brought it in.

Johnson: Before you went to cold gasification, you were working on Skylab, and your 

testing actually showed there was going to be a problem?

Tepool: We ran a dynamic test on the Skylab module, and it had a meteoroid shield on 

it. That meteoroid shield fit in tight during launch. When you got to altitude, it popped 

out about a foot and a half. If a meteoroid hit it, it would not penetrate it and the 

vehicle. There was a seal on the top and bottom of that thing, a big rubber seal, that was 

to hold out the air when you were launching. When we ran the vibe [Vibration] test on 

it out in the big Dynamic Stand, we were vibrating and measuring pressure under that 

seal in that cavity. That seal would fail due to the vibration. It would leak. We told them 

it was going to leak and if it leaks, we do not know what will happen, but it is not a 

good seal. They said they would not hold up the launch and were shipping anyway. 

They launched it at the Cape and it came apart that night. We went out and looked at 

the sky and it looked like a train going across all the parts and pieces that were shining, 

coming along behind it. They appointed the same guy that made the decision to take it 

down there and launch it to run the investigation. I am not going to say who that was. 

(Both Laugh)
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Johnson: The test engineers were all looking at each other saying, “We told them it was 

not going to work.”

Tepool: That is exactly right.

Johnson: That sort of begs the question, did that happen other times?

Tepool: One other time, and that was on the Shuttle Program. We have a test stand out 

there in the test area called Test Stand 116. It is an acoustic model test stand. We take a 

one-fifteenth scale of a shuttle. We used tomahawks for the solids, had three engines for 

the main engines, small model engines, and fired it. We fired it into an exact simulation 

of the Cape launch facility, the Cape launchpad. When we did that, we measured the 

acoustic noise and over pressure coming back out and bouncing off the vehicle and 

payloads. There was an over pressure that came out of that hole almost strong enough 

to snap the wings off the orbiter. We wrote our report, told them there was over 

pressure that comes out of that hole and it is not good. We were scale, we were onefifteenth, and they though that would not happen at full-scale. The first time we 

launched, we almost snapped the wings off the orbiter. 

Johnson: What launch are we talking about here?
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Tepool: STS-1.

Johnson: With the guys onboard.

Tepool: We never launched an orbiter without anybody onboard.

Johnson: That is what I am saying.

Tepool: They had parachutes, remember, they could shoot themselves out on the very 

first one.

Johnson: It is a little hard to understand. You are giving them the bad news and they do 

not want to hear it.

Tepool: They do not think it is going to happen at full-scale. They think it is a scaling 

problem.

Johnson: Then why do the test at scale?
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Tepool: You can do the test at scale for acoustics. We have done that before. When we 

launched, they did accommodate by putting measurements at the launchpad. When we 

launched, we did get the over pressure, did not snap the wings off, thank goodness, 

everything was copacetic. That is when we came up with the water wienies. Have you 

ever heard of the water wienies?

Johnson: No.

Tepool: What they did was build these canvas bags and strung them across the opening 

at the Cape and filled them full of water. When that overpressure wave would come up 

there, it would hit those and the water would dampen it out and it would not come up 

to the vehicle. The vehicle would be gone before it would get there. It would slow it 

down so it could not get up there and that overpressure wave hit those wings.

Johnson: We did not do this for STS-1, but after STS-1.

Tepool: We did it for a long time, yes. Then we would put in more big water 

suppression systems to kill it.
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Johnson: Compare the Saturn V and shuttle, if you would. Was the test program 

different as far as you were concerned, or was it a similar-type approach to making sure 

everything worked as it was supposed to?

Tepool: It was s similar-type approach except in the Apollo Program, every component 

was what we call qual. [Quality] tested and life cycle tested. In other words, it was 

tested two or three times its life. It was tested to extreme limits by an independent qual. 

test organization. 

Johnson: Quality.

Tepool: Quality, right. It cost big bucks, big bucks.

Johnson: When you say big bucks, what are we talking about here for a test like this?

Tepool: I am not sure. When I was running Test lab, we were spending around 120 

million a year and we were not hardly doing anything. 

Johnson: The big tests were expensive.
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Tepool: Yes, the big tests are expensive. You have 500 thousand gallons of LOX and fuel

onboard. It is costly.

Johnson: Was there any static from up above about how much you guys were spending 

on tests?

Tepool: No, not on Apollo, not on shuttle.

Johnson: This was something that had to be done.

Tepool: Right. But then they took a different philosophy. On shuttle, instead of running 

all these qual. tests, they took a bunch of experts in each, turbomachinery, combustion 

devices, actuators, different things, and they sat them down and said, “Write down 

what you have to do with this component before you can fly it.” In other words, it was 

called a development verification system. Going through development, what do they 

have to do to verify that it is ready to fly? These experts would write down what they 

thought had to be done to verify that. That was in lieu of the qualification test program.

When we got ready to fly shuttle, there were several development verification 

engineers. Each component had a father, or a guy in charge, that had to prove. In 

shuttle, there were some verification engineers who were not willing to sign up for the 
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first flight. The program manager took it on himself, [James Robert] J.R. Thompson [Jr.], 

and signed the waivers to fly that stuff.

Johnson: You mean the verification engineers, they would not put their names down on 

a piece of paper that their this is ready to fly?

Tepool: Right, so J.R. did. That is a project manager’s call. That is why he is the project 

manager.

Johnson: In your mind, was doing it that way a good idea? Not criticizing him, but as a 

test engineer.

Tepool: In my mind, not necessarily a test engineer, that was a great call politically 

because to get the shuttle going. Some of these guys would have never signed up.

Johnson: That is sort of how people felt for a lot of the shuttle program, they never 

would have signed off on it. 
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Tepool: Right. That was a good call to go on and do that. Technically, it probably was 

not that great a call because we were flying on the edge there for a few years before we 

got it all right.

Johnson: You were with the main engines. As far as being a test engineer, I guess it was 

a joy.

Tepool: It got pretty tough. We were blowing them up, having failures. We had two or 

three cut themselves off, torch themselves off at the gimbal block and fall it the bucket. 

We were having a hard time.

Johnson: Was it a tougher engine to develop than the main engine of the Saturn?

Tepool: Yes, because it is a stage combustion engine. The Saturn engines were G.G. 

cycle engines, which were gas generator. What they do it have a small engine running 

that turns their pumps. That fuel then goes overboard. On a stage combustion engine, 

everything you do goes into the main chamber and burns. If you have a little problem 

anywhere in the system on a stage combustion engine, the whole system is going to see 

that problem all the way through. 
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Johnson: A little problem becomes a big problem. 

Tepool: Can become a big problem.

Johnson: Once you had done the testing and ironed out the problems, was there a 

problem with the shuttle engine that you thought you were not going to lick? Did you 

think you would just keep working and find out what the problems are?

Tepool: We used to change the LOX pump bearings every flight. When Challenger went 

down, I was sitting in a conference room going to telephone school. We got new 

telephones. We had it on TV [Television] as it was launching and it blew up. I swore it 

was the LOX pump.

Johnson: You thought it was the main engine?

Tepool: I thought it was the main engine LOX pump because of the problems we were 

having with the LOX pump. But it was not.

Johnson: In fact, the main engine.
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Tepool: Was fine.

Johnson: Over the life of the shuttle, thirty years.

Tepool: [It was] one of the few. We had problems, but we fixed them. We never had inflight problems.

Johnson: The testing for that, that was where you got it right.

Tepool: Right. We got it right, not me. (Laughs) There were a lot of us. 

Johnson: Was there a different fell from what you did in the Apollo Program to the 

shuttle?

Tepool: No, it was all the same. The feel changed after shuttle, at the beginning of the 

Ares Program. 

Johnson: As far as getting through the shuttle as a test engineer?
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Tepool: By that time I was not a test engineer anymore. I was the chief engineer up in 

the project office on the main engine. We still oversaw all the testing that was getting 

done.

Johnson: When you started, it was a slide rule world. By the time you retired, computer 

simulations were doing some of the work, am I correct?

Tepool: Oh, yes, everything.

Johnson: As a test engineer, did you like that or did you miss the original days?

Tepool: I am still not the computer guru or geek. If somebody wants me, do not send 

me a text message or leave me a message on my phone. Either call me or come see me. If 

you cannot call me, do not be texting me or send me email [Electronic Mail]. That is not 

communication. That is one-way stuff. Back in the old days, if you wanted somebody, 

you called them. If you could not get ahold of them, you went to see them, make sure 

they knew what you needed and you knew what they needed to get the job done.

Johnson: On that same note, yes, you have the computer simulations now, but it sounds 

like you do not think the communication is as good.
Steve Johnson Interviews – Apollo/Saturn Program

Date 30

Tepool: Right, that is it, it is communicating now. The simulations and everything now, 

that is great. Computers can do things what it took us years to do and they can do them 

in a nanosecond. In fact, the dollar calculator you buy at the dollar store, that was four 

hundred some dollars when I was in college. The very first Texas Instruments, it could 

take the square root, multiply and divide, it was about $450 back then. Now you can get 

it for a dollar. 

Johnson: I know there were computers, but they were pretty primitive at the beginning, 

were they not?

Tepool: Yes, we had Beckman line printers. Our computer room was probably 4,000 

square feet. Now everything that computer could do, you can do on a laptop. 

Johnson: It was 4,000 square feet?

Tepool: Full, top to bottom.

Johnson: Let us go back to the Saturn V. When it was finally launched and all the parts 

went together and all the systems were integrated, what was that like to know that you 

helped make that possible? How well did it all fit together?
Steve Johnson Interviews – Apollo/Saturn Program

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Tepool: I did not get involved in fitting the total bird.

Johnson: I know that, but as a guy who was part of it, when you saw it all go together 

and do what it did, what did you think?

Tepool: Just like I think now, with enough time and money, you can do anything. There 

was a lot of time spent, a lot of people, and a lot of money. There was no doubt I 

thought it would ever come together. We had the S-IC stage here, they were doing the 

S-II stage out in Downey [California], the S-IVB stage was at McDonnell Douglas. 

Rocketdyne was building all the engines and shipping them to these places. We were 

putting them on. We were testing, they were testing. We shared experiences. If they had 

a problem, they would let us know. If we had a problem, we would let them know. The 

real thing that was more amazing to me than technically getting the job done was how 

they scheduled and maintained all the logistics of making enough LOX, making enough 

RP-1. We were making enough high strength steel bolts that we needed. On the Saturn, 

we had two sets of suction lines, two sets of prevalves, two sets of that valve, different 

vendors making these in case one did not work. There was a lot of money spent in 

protecting that decade thing.

Johnson: The promise to launch within the decade.
Steve Johnson Interviews – Apollo/Saturn Program

Date 32

Tepool: Right, which did not happen in shuttle. Shuttle was more we have a problem, 

we have to fix it, we are going to slip schedule. When we had the failures in shuttle, 

were down for three years with Challenger before they would let us go back and fly 

again.

Johnson: Was that frustrating when you had the problems?

Tepool: Yes, same way on Columbia. I was on both those investigation teams. You know 

what happened right away. It was a matter of fixing it. There were so many hoops to 

jump through to get everybody’s approval and go fly it.

Johnson: Talk about the difference between Apollo and shuttle. In retrospect, did you 

feel like the shuttle design was a good one compared to how the Saturn V seemed to be, 

this is exactly how we should have done it? The shuttle, I have heard it described by a 

veteran shuttle worker that is was a little more complicated than it needed to be. As a 

test engineer, what do you think?

Tepool: It was a little more complicated. I would not have used solids. I would have 

used liquid boosters instead of solid boosters so you can turn them on and off. It would 

have been safer. With solids, there is nothing you can do. If it decides to go, it is going 
Steve Johnson Interviews – Apollo/Saturn Program

Date 33

and it is too late. I think the orbiter itself, we went for weight a lot instead of brute force. 

In Apollo, we went for brute force. In shuttle, we went for save weight, more 

performance, that kind of thing, which is very costly and very fragile. Originally, the 

shuttle was not going to have the heat shields on it, the thin heat shields. It was going to 

be pretty beefy and cooled.

Johnson: That was changed for weight?

Tepool: I am sure it was. Have you talked to [Robert J.] Bob Schwinghamer?

Johnson: No.

Tepool: You need to talk to Bob. (Laughs) He was head of the Materials Lab for years 

making all this new stuff. 

Johnson: Did you work with multiple centers? I am sure you did. Was there a 

difference between the centers? In your mind, were there rivalries?

Tepool: Yes, competition.
Steve Johnson Interviews – Apollo/Saturn Program

Date 34

Johnson: Good competition? Bad competition?

Tepool: It depended. The manned spaceflight centers competing with the science 

centers and the other part of it, Ames [Research Center], Dryden [Flight Research 

Center, now Armstrong Flight Research Center]. The manned center seemed to get 

along pretty well, which is JSC, Kennedy [Space Center], Marshall, and Stennis [Space 

Center]. The other centers, we did not have a lot to do with them, but we felt like they 

were spending a lot of money doing research that never went anywhere. (Laughs)

Johnson: That you could have used the money.

Tepool: That we could have used to go somewhere or do something. (Laughs)

Johnson: Did the rivalries get in the way during the programs you worked on, what 

you tried to accomplish?

Tepool: No. In fact, the centers pulled together pretty well. Stennis used to be a part of 

Marshall. The Cape used to be a part of Marshall. When I came here, Marshall did the 

launching, Marshall did the testing, Marshall did everything. Then they started Cape 
Steve Johnson Interviews – Apollo/Saturn Program

Date 35

Kennedy. The Marshall people went to Cape Canaveral to launch originally, until 

Kennedy Space Center was started. 

Johnson: What about the contractor experience? You worked with contractors, I am 

sure, very often and extensively. Generally speaking, was it a good experience working 

with contractors?

Tepool: Yes, especially in the test world and in the propulsion world. The only bad 

experience working with contractors is that they are pretty good, they are working with 

you and their peers, but when a program gets cut, they are the first to go. You may have 

some people in your own ranks that are not as good as your contractor people, but that 

does not matter. They are the first to go. That is where it gets tough. 

Johnson: Did cutting contractors ever hurt the program, slow you down, maybe?

Tepool: Maybe slow you down, but it did not hurt you. It did not make you do 

anything unsafe. It did not affect the flights.

Johnson: How about NASA Headquarters? During the Saturn days, during the Apollo 

Program, during the Shuttle Program, did Headquarters help or get in the way?
Steve Johnson Interviews – Apollo/Saturn Program

Date 36

Tepool: When I came here, Marshall was more Headquarters than Headquarters was, I 

think. I was at a junior level, but von Braun kind of ran the manned part the way he 

wanted to, even though he was the Marshall director. When they shipped Wernher out, 

the talk on the street was that was so Headquarters could get control of the centers.

Johnson: When von Braun was in charge of Marshall Space Flight Center, you already 

said people were excited and that the work went well. After he was gone?

Tepool: It got tough, but it is hard to realize whether that was the influence of him or 

because the Apollo Program ended. They brought in Rocco Petrone from the Cape. His 

job was to get rid of the Germans at Marshall Space Flight Center and make Marshall 

answer to Headquarters. That is what he did.

Johnson: What do you think of that decision or job? Do you think that was a good idea?

Tepool: Probably sooner or later it had to happen, I would think. You cannot have one 

center running wild when you have ten centers around the country. Headquarters, 

centers, it almost all boils down to who is heading the show there, who is the center 

director at Marshall, who is the center director at the Cape, who is the center director at 
Steve Johnson Interviews – Apollo/Saturn Program

Date 37

Stennis, who is the administrator at Headquarters and then who are the deputy 

administrators up there. They have more influence on how things operate than just 

Headquarters in general.

Johnson: Did you sense during the programs you worked on, but especially the Apollo 

Program and the shuttle, that you were a part of making history, doing things that had 

never been done and it may be a while before they are done again?

Tepool: We thought we were living the dream. We were having a big time. NASA was 

kind of a premier agency to work for. People respected you if you told them you 

worked for NASA or they knew you worked for NASA. If I had known back at the 

beginning, I would have saved a lot more paraphernalia. (Laughs)

Johnson: The history part, you really did not think about it. Do you think about it now?

Tepool: Every once in a while. It has been fifty, fifty-two years since NASA has started. 

You see people that have things that people gave them from NASA and they think it is

a big deal. Some of them are and some of them are not. (Laughs) There were millions of 

them printed, maybe. I am glad I had a career with NASA. I am very thankful that it 
Steve Johnson Interviews – Apollo/Saturn Program

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helped me put four kids through Auburn [University]. Now I just hope the government 

does not go broke before I die. (Laughs)

Johnson: We know how much recognition von Braun and the German rocket team 

received. Do you think the rest of the workforce received the credit due them?

Tepool: Some did and some did not. Some got more than they deserved, but that is just 

the way it goes. Who is the rocket boy?

Johnson: Homer Hickam.

Tepool: Homer, yes. I do not know if he even saw von Braun, to tell you the truth. He 

was never out there when I was out there. If you read his books, you would think he 

did everything. 

Johnson: If you were going to bottom line your career with working on the things you 

worked on as a test engineer, it strikes me that you pretty much got to be where the 

action was.
Steve Johnson Interviews – Apollo/Saturn Program

Date 39

Tepool: That is right. That was the good part. I was in tests for thirty years and I spent 

the last fifteen in shuttle. I would always go back to tests, see the guys. It is a certain 

kind of guy that wants to work in tests because you kind of get to do your thing. You 

have to be a little bit cocky because you cannot let people come in and say, “Why do 

you not do this? Why do you not do that?” You have to know what you want to do and 

go do it. You do not want any A students. My hardest job when I was running tests was 

to get a good test engineer. NASA always wants to hire A students. If a guy is a real 

straight A student, really wants to dig in, he does not want to run tests, he wants to 

develop something. He should be in a lab somewhere. He should not be out on a test 

stand, trying to get work done, get all of his guys lined up, tank, fire, fix, get ready to do 

it again, modify procedures to do that. I had some test engineers that would never run a 

test because they were always checking the stress guys’ work, the thermal guys’ work. 

They were doing all that rather than getting ready to run a test because that is what 

they liked to do. They do not make good test engineers.

Johnson: Basically what you needed were some garage mechanics who had an 

engineering degree?
Steve Johnson Interviews – Apollo/Saturn Program

Date 40

Tepool: Right, that is right. (Laughs) That is really right. Or you needed somebody that 

knew a lot about a bunch of different things and was more systems oriented instead of 

one area.

Johnson: Where were you? How did you fit in?

Tepool: I am observant. That is my best strength. I see a lot and do not make the same 

mistake twice a lot. That is how you learn, by mistakes. When I came here, I did not 

know what a solenoid was. I did not know what anything was. I knew how to calculate 

stuff, I knew the engineering behind it, but I did not know how it all worked. The 

technicians teach you how it works. Every engineer, he is going to learn from somebody 

who does hands-on, some tech in some shop, some manufacturer somewhere. That is 

where he is learning. Book learning does not do anything for you when you get out in 

the world. You know where to go to find out how to fix the problem you are having, 

but it does not tell you how everything works.

Johnson: You had to get your hands dirty to do what you did.

Tepool: Yes. It is a good thing we did not have strong unions. (Laughs)