NASA Office of Logic Design

NASA Office of Logic Design

A scientific study of the problems of digital engineering for space flight systems,
with a view to their practical solution.


This material is taken from SP-4223 "Before This Decade Is Out..." which has biographies and interviews of many key personnel.

Return to "About Max Faget"


During his nearly 40-year career in government service, Dr. Maxime A. Faget has made many distinguished contributions to the advancement of aeronautics and astronautics. Internationally known as the chief designer of the Mercury spacecraft, he has played a major role in developing the basic ideas and original design concepts that have been incorporated into every manned spacecraft that the United States has since flown. From his early research in supersonic flight, through the design and development of the Space Shuttle, Dr. Faget's engineering acumen is evident throughout in the development of aircraft, missile, and spacecraft research and design techniques.

Born on August 26, 1921, in Stann Creek, British Honduras, Faget graduated from Louisiana State University with a Bachelor of Science degree in mechanical engineering in 1943.1 Upon graduation, he joined the Navy as a naval reserve officer assigned to submarine service. Completing his military service, Faget became employed with the National Advisory Committee for Aeronautics (NACA) Langley Aeronautical Laboratory in 1946. He was assigned to the newly created Pilotless Aircraft Research Division (PARD), a division that flew rocket-powered models of aircraft and missiles at transonic and higher velocities to obtain aerodynamic data. It was during this period that Faget was first exposed to the idea of space flight while pioneering work on supersonic inlets and ramjets.

While at Langley, the NACA established a group to study and define problem areas that had to be solved to make space flight a practical reality. In March of 1958, Dr. Faget presented a paper called "Preliminary Studies of Manned Satellites-Wingless Configuration, Non-Lifting" at a conference held at the Ames Aeronautical Laboratory in Moffett Field, California. This significant paper put forward most of the key items that were later used in conducting the Mercury Project. It showed that a simple, nonlifting satellite vehicle of proper design could follow a ballistic path in reentering the atmosphere without experiencing heating rates or accelerations that would be dangerous to man. It also showed that a retrorocket of modest performance was adequate to bring this capsule down from its orbital speed and altitude to a reentry into the atmosphere. In addition, it outlined the possibilities of using parachutes for final descent, and small attitude jets to control the capsule in orbit, during retrofire and reentry. His paper concluded with a statement that "as far as reentry and recovery are concerned, the state of the art is sufficiently advanced so that it is possible to proceed confidently with a manned satellite project based upon the ballistic reentry type of vehicle."

When NACA became NASA in 1958, among the new organization's responsibilities was that of manned space flight. Dr. Faget was one of the original 35 members selected to form the Space Task Group (STG) which later developed into the Manned Spacecraft Center (now the Johnson Space Center). Although Mercury was the main task of the STG, there was great interest in developing follow-on programs. As chief of MSC's Flight Systems Division, Faget devoted a large amount of time to heading a design and analysis team that explored manned flight to the vicinity and the surface of the Moon. Because of this and other NASA studies, President Kennedy was able to commit the U.S. to a lunar landing by the end of the decade. With the advent of Apollo, Faget was appointed chief engineer at MSC where he was responsible for the design, development, and proof-of-performance of manned spacecraft and their systems. This responsibility also included specifying the function and design of numerous engineering laboratories to be constructed as part of MSC. In April 1969, shortly before the first lunar landing, he organized a special preliminary design team to do an intensive feasibility study of a reusable manned spacecraft. This effort achieved program status when MSC was given the formal authority to develop the Space Shuttle. As a result, Faget focused the ensuing years on solving the numerous problems and technical challenges associated with the space shuttle until his retirement from NASA in 1981.

In 1982, Faget joined with several Houston businessmen and founded Space Industries, Inc. (SII). His company manufactured a wide range of experiment support equipment that has flown on numerous shuttle missions. The most significant of these was the Wakeshield Facility built for the University of Houston. This free-flyer was successfully deployed on two missions, providing experimenters with an ultra-high vacuum environment for materials processing.

Faget's numerous accomplishments include patents on the "Aerial Capsule Emergency Separation Device" (escape tower), the "Survival Couch," the "Mercury Capsule," and a "Mach Number Indicator."

Dr. Faget served as a visiting professor and taught graduate level courses at Louisiana State University, Rice University, and the University of Houston. He has also received numerous honors including the Arthur S. Flemming Award, the NASA Medal for Outstanding Leadership, and an honorary doctorate of engineering degree from the University of Pittsburgh.

Faget is married to the former Nancy Carastro and they have four children; Ann Lee, Carol Lee, Guy, and Nanette. The Faget's live in Dickinson, Texas.


Editor's Note: The following are edited excerpts from two separate interviews conducted with Maxime A. Faget. Interview #1 was conducted June 18-19, 1997, by Jim Slade, as part of the Johnson Space Center Oral History Project. Interview #2 was conducted on December 15, 1969, by Ivan Ertel and Jim Grimwood.

Interview #1

I believe in 1962 you were named director of engineering and development at the Manned Spacecraft Center, Houston. How did your day-to-day role change, or did it?

Well, it didn't really change. It was pretty much the same thing. The thing that was most important had to do with the move as opposed to the change in title. We came to Houston. We had to build a center. All of the engineering facilities had to be specified, worked out, negotiated, and an organization had to be built. We went from essentially a one-man, one-program project, [Mercury] to really trying to do three programs at once [Mercury, Gemini, and Apollo], plus build the center.

 

You were trying to telescope three levels of thinking-Mercury, Gemini, and Apollo. You were trying to do all this at once. Was that at different levels?

As far as Mercury was concerned, that was out of Engineering. We didn't have anything to do with it other than saying, "Yes, it's all right to fire, to leave the retrorockets on," which was about as much engineering as I did then.

And Gemini really didn't require an awful lot. There were a few new things on Gemini. There were the fuel cells along with their cryogenic oxygen and hydrogen storage systems. Also, Gemini was designed to be able to make significant translation maneuvers that required the use of a much more powerful auxiliary propulsion system. This was all carried in the adapter section that stayed attached to the capsule until reentry. Gemini also had an offset center of mass to provide a small lift vector so that it was able to maneuver during entry to minimize splashdown dispersion. You....


Maxime A. Faget, assistant director for engineering and development, Manned Spacecraft Center, explains the function of the lunar excursion module to Father Patrick J. O'Brien, Mrs. Faget, and Mrs. Donald J. O'Brien, sister-in-law to Father O'Brien. This photo was taken on September 15, 1965.

Maxime A. Faget, assistant director for engineering and development, Manned Spacecraft Center, explains the function of the lunar excursion module to Father Patrick J. O'Brien, Mrs. Faget, and Mrs. Donald J. O'Brien, sister-in-law to Father O'Brien. This photo was taken on September 15, 1965. (NASA Photo 64-31226.)


....know that Gemini was primarily the result of Bob Gilruth insisting with NASA Headquarters that it was essential to have more experience in space operations before we tried flying to the Moon. I'm convinced we would have never been able to make the landing in Kennedy's decade without the training and operations development that Gemini provided . . .

Apollo was the big driver as far as engineering was concerned. We had to get that under way with Apollo. No doubt about it. We just selected the program for Apollo and had to go with it.

 

And you were using Gemini as a testbed for so many of the particulars of Apollo, weren't you, the rendezvous and docking, the maneuverability of the spacecraft?

Rendezvous, docking, extravehicular activity . . . But that came about after it got to flying. The focus of modularization was still primarily on Apollo. We were going from a single vehicle to a two-vehicle system and had to come up with the specifications for the LM [lunar module], and do the whole procurement bit. That was a big effort. We'd actually, of course, done the procurement for the command service module while we were still in the [beginning of] Gemini . . .

We actually started looking at lunar flight, I guess, six or eight months after the birth of NASA. I remember Headquarters was trying to look at the future and understand what was going on. Well, one of the first things Dr. T. Keith Glennan did was create a group under Bob Gilruth to do the manned program. He put Bob Gilruth in charge of manned space flight. We didn't call it Mercury at that time. We still called it "the capsule." [Laughter]

So Gilruth had a couple of meetings, and then he went in and reported to Glennan. So NASA must have been about two or three weeks old. He told him where we were, that we'd selected this capsule shape and we were going to do this. Finally, Glennan said, "Well, that's fine. That's fine," he says. "Now what do you want me to do, Bob?"

Bob said, "Well, I think I want you to tell me to go ahead."

So he said, "All right. Go ahead. Do it."

So Bob Gilruth goes back, and he talks to the head of Langley, Tommy [Floyd L.] Thompson, and he said, "You know, that guy told me to go ahead, but he didn't tell me how. I haven't got any organization. I don't know how I'm supposed to do this."

They got their heads together, and Thompson said, "Well, why don't we just create the Space Task Group." So Tommy Thompson created the Space Task Group within Langley to do this job and put Bob Gilruth in charge of it . . . And then they got together, and they named 35 people . . .by letter that Tommy Thompson signed, that created the whole thing.

 

You say that you were basically most interested in Apollo when you came over to Houston. How much input did you have in the Gemini spacecraft? Was it just an extrapolation of Mercury?

It was an extrapolation of Mercury. It was not competed. What happened was, a man named Jim [James A.] Chamberlin came in. He's the guy from Canada, from AVRO. He brought a bunch of Canadian engineers with him, which was really a godsend, because that put some real experience into the group. Bob Gilruth put him in charge of the day-to-day management of the Mercury Program. He created an organization and put me in charge of what amounted to engineering, although it was a different title, but it was essentially doing the same thing I ended up doing.

He and the people at McDonnell . . .were looking at all of the shortcomings of Mercury, because, as you pointed out, Mercury was not a vehicle that was controlled by people, but by the occupants. Mercury was a vehicle that just went up and came back down. It didn't do anything except stay in orbit until it was time to come down. They recognized that they wanted to do more than that, so they conceived of this program.

When Bob Gilruth told me about it, I said, "Well, they ought to have at least two people in there." That was my contribution: "They ought to have two people in there," so they made it bigger and put two people in there.

It's kind of interesting, Jim Chamberlin was really kind of the force behind the Gemini Program. There's just no doubt about it. Gilruth liked the idea of two people. He told McDonnell that they ought to have two people in there. Jim was the last one to find out we'd decided to put two people in there. [Laughter] But he thought it was a great idea, too. So we had enough to do. Titan was going to be big enough to carry two people.

 

That spacecraft was built by the same manufacturer as Mercury, yet Gemini did not use your escape tower. Why was that? Because of the Titan?

No.

 

Apollo did use your escape tower?

Yes. Well, that was somewhat of an aberration, and I argued long and strong against what they did, but they did it anyway. In the original concept, Gemini was going to make a land landing using a gliding parachute and they wanted to put ejection seats in it. In the event that something went wrong with the gliding parachute, instead of having a back-up parachute, they'd just eject. So they had the thing designed with ejection seats from the beginning. They said, "Well, we've got ejection seats. We don't need to put the escape tower on there." And there was a little bit of rationale there. The fact that they were using hypergolic propellant meant that the fireball would not be near as big. Now, you might say, "Gee, you're going to use hypergolic propellant where you just touch it and it's going to go off and you are going to have a smaller fireball?" Yes, that's the case.

The thing about liquid oxygen and kerosene is that they can mix quite a bit before they go off. You can't mix hypergolic propellants. The minute they start to mix, they go off, and for that reason they'd blow each other apart, and the amount that ends up getting involved in the fireball is very small. You can see if the tank were to spring a big leak or an opening, the propellants could mix quite a bit and then go off. Of course, then you'd have a really big explosion. So that was the thought.

But the bad part about the ejection seats, they probably would not have worked much over about 20,000 feet of altitude just simply because the velocity would have been too high. If you had to eject very quickly while the rocket was still firing in the back, for some reason or another, you were liable to go right through the fire from the rockets. The best thing about Gemini was that they never had to make an escape . . . Chris [Kraft] will tell you the same thing. If you ask him what he thinks about the ejection seats, he'll say, "I'm glad we never used them." [Laughter]

 

It seems to me that ejection on the pad with an impending explosion would probably have killed the astronauts. Or am I figuring that wrong, because it would have been a lateral ejection?

The ejection on the pad would have been quite marginal, no doubt about that. The parachute would open, and the man would make maybe two swings on the parachute before his feet were on the ground. You know, thank God we never did that . . .

 

Interview #2

I know you had a couple of meetings in September, and then on October 27, 1960, which defined the shape of Apollo. I'd like to get some of your thoughts leading to that date where you do get the shell of the vehicle outlined and some of the interior arrangement aligned.

Let's talk about the development of the shape. That's kind of a separate thing because as long as I get down that train of thought I'll think of some of the other things that went on at the same time. I don't know when the idea first came that we would go to the Moon and back. I do remember that one of the first things was the old military high ground approach-the military were the first ones who wanted to go to the Moon. They had funded studies on that. Once Mercury got started and we set aside two or three people-certainly by the end of 1959 we had two or three people-thinking about what might come next. Kurt Strauss was the key man working at that time on the Apollo program. Of course, Bob Piland was my assistant and a good bit of his time went on that.

When we got to thinking about going to the Moon we were faced immediately with the fact that reentering at 40 percent greater speed . . . at that time a lot of the entry experts started talking about hot gas cap radiation heat which is a very fancy way of saying that in the shock wave that stands in front of the entry body the molecules are first broken down into atoms and then further broken down so the electrons split off the atoms due to the energy of the air running in the shock wave. Subsequent to that, the atoms recombine, the molecules recombine, and the heat recombination is released in radiant heat. It is theorized that this radiant heat would be a predominating factor. As a matter of fact, early in the Mercury program it was considered that maybe the radiation heating might be a predominating factor even at the entry velocity of Mercury. We realized very shortly in the program that after Big Joe,2 and a few flights like that, this wasn't going to be the case. But that just allowed the theoreticians to encourage them to move their velocity of concern up a little higher.

Now, it turned out that the blunt body is best to protect against the conductive heat transfer which is the nominal heat transfer of heat from the vinyl area of the surface, whereas the blunt body is the worst offender from the standpoint of this radiation heat transfer because the blunt shock wave that is formed-the blunt body- maximizes the strength of the shock wave. The stronger the shock wave is the greater tearing up of the molecules and, consequently, the greater would be the subsequent recombination in the radiation. The whole business of estimating this type of heating is based on analysis that required assumptions that you would not be able to verify by experiments. Estimations of this radiation heating varied over a factor of about 20-from the worst case, to practically none at all. Of course, if we'd taken the worst case, the blunt shape- such as we used in Mercury-was not a very good shape to use. The result of this was to cause a reconsideration of the basic shape.

Two main contenders were the M-1 shape, which was the shape that Dr. [Alfred J.] Eggers, Jr. had designed which was a half cone with a very small blunt base to minimize radiation heating. Another one was the lenticular which would come in edgewise because that had a low heating, and GE had a shape which was kind of a conical shape. There was great concern over the amount of lift over drag (L/D) that would be required during entry. The basis of this concern was due to uncertainty of the entry navigation. Dr. Harry J. Goett was probably one of the most pessimistic of the group. Frankly, he was completely uncertain that we could navigate back from the Moon. Depending again on the estimation of how accurate one could navigate back into the earth's atmosphere, i. e., how close to the center of the entry corridor you could hit, was a great determining factor on how much drag you needed. If you could hit close to the center of the corridor, lift to drag-high lift to drag capability was of benefit because it would allow corrections in navigation areas before either the heating on the G's got too high on the one hand, or on the other hand before you skipped out. You could pull negative lift and hang in there. The Mercury type shape, blunt heat shield shape, was admittedly limited to about L/D of a half, and a lot of people felt we at least needed L/D to one and some of them were suggesting L/D of one and a half. That's about as high L/D we could have. The higher L/D, the lower the drag and consequently the lower the efficiency as a reentry body. So we had a lot of things going.

The people at Ames were the first ones to come up with some fairly good analyses that showed that the hot gas gap radiation wasn't as severe as the worst predictions. [Clarence A.] Syvertson was one of the guys who did a lot of work to that end. Then we had started doing some studies with MIT [Massachusetts Institute of Technology] and got a lot more confidence in our reentry navigation. So by the time that we were in the middle of these three funded studies, we weren't overly concerned about the hot gas gap radiation. The worst that the blunt body type would experience would negate its basic advantages in low heating.

On the wing vehicles, the high L/D's were not needed anymore. I guess I got bold enough to tell them that. I had a feeling that was right all along. It's one thing to tell them, but it's another thing to tell them with authority that they'll believe you, and I think we gained their confidence that we didn't really punish ourselves heating wise by going with the very blunt vehicles. We stood a chance to come out ahead-at the worst situation on radiation would be about an even trade off comparing a blunt body to some of the more pointed bodies. On the other hand, we'd come out way ahead. It turned out that the lowest estimate we made was the one we actually experienced.

During the time of the studies, we set our own people to work and we had two concepts in-house, one was the M and M shape or the lenticular vehicle, and the other was the derivation of the Mercury which was like a Mercury shape only it had a shorter afterbody because we planned to fly it at a high angle of attack-we didn't want the afterbody to be exposed. We made the conical angle blunter back there. At the same time that we were beginning to get some favorable answers on the heat radiation and some definitive analysis on the accuracy of the return navigation, and we felt pretty certain . . . and this came not only from MIT but from our three study contractors. All of their navigation analyses indicated that we stood an excellent chance of being able to get in a very narrow corridor, so now instead of just having Harry Goett's conservative feelings that we might not be able to make it, we had some very definitive studies that indicated that state of art navigation supported a very good chance of getting into the 10-mile corridor. Of course, if anybody said now you had a 10-mile uncertainty, it would sound terrible the way we're navigating these days. Mind you, we were trying to prove that things weren't like 100 miles. Ten miles was good enough to support the L/D of a half vehicle. So along about the middle of the study period we put the word out that we thought the L/D of a half was adequate for entry navigation and there was no necessity to be overly concerned about the hot nose cap radiation.

Meanwhile, our own in-house studies . . . looking at both lenticular and the Mercury derivative shape, the main reason for the lenticular shape was to try to get a L/D of an excess of one hypersonically and the interest in that shape decreased when we found we didn't need that high L/D. It also looked like it was not as competitive from a standpoint of heat protection system as a low L/D.

Radiation also influenced the progress of the design. I guess there was a number of configuration drivers in addition to just the reentry shape that we were concerned about. We decided early on that we were going to make the thing big enough. We were just at that moment experiencing all the bad things that came out of making Mercury too small. One of the things we set as a policy in all our design studies was an adequate amount of volume inside the command module. One of the other things that was being studied was the possibility of a two-compartment vehicle as opposed to a one-compartment vehicle. Now I'm not talking about LM's or anything like that. The mission during this period was merely to go into orbit around the Moon or just circumnavigate the Moon and back. We were looking at about a one to two-week long mission and it would terminate with the reentry. Now in order to have enough volume, of course, they had to make the thing bigger which meant we had to carry along a lot of extra heat protection systems, so it seemed a very attractive thing to divide that volume in two pieces. We had for a long while a command module and a mission module, the mission module being where everybody was supposed to do their business.

This started off to be a very attractive idea but as we went through our own studies and the contractors went through their studies it became clear that less and less things were going on in that mission module, and everything that was vital for one reason or another also was vital during entry so you either did it twice, once in the mission module and again in the command module, or you did it once in the command module. So it seems that the mission module was turning out to provide nothing but extra room. There were no systems and no particular activity that anyone really wanted to carry out in the mission module other than to stretch out and perhaps get a little sleep. The consequence of this was that it didn't look like it was worthwhile to have a mission module. So in the final analysis we ended up with a single cabin version. You might have noticed that the Russians ended up going into something very close to our two-compartment vehicle that we were considering. I don't know where they got their ideas, but it might have been from us. We made no secret of these considerations.

The entire layout of the vehicle became very important at that time and we had a couple of people make very detailed designs. I think the most notable people here were Owen Maynard, Larry Williams, and Will Taub. There may have been others but I don't recall them. Of course, Caldwell Johnson was leader of that group. Will Taub, I think, constructed a 10-scale cardboard mockup of the vehicle and we also constructed several full-scale plywood mockups of the vehicle during that time. The purpose of all this was to make sure there was enough room for everybody inside and that everything would work together. The layouts that we ended up with are very definitely derivatives of that early work. The command module in many ways is pretty much laid out the way those fellows said it should be . . .

There were some other things that we did at that time that helped set the shape. We had a fairly lengthy argument about whether the bottom of the heat shield should be rounded-the point where the heat shield and the conical part intersect. Mercury and Gemini are sharp and in Apollo we rounded that off. I thought it should be sharp because I couldn't see anything wrong with it and it also increased the total drag.

One of the primary things that I think settled the issue was that on the early Saturns, which had been designed primarily as a R&D vehicle down at Huntsville, they designed this vehicle and got the go ahead to put two or three of them into production for test flights without any payload. So they had several old Jupiter nosecones laying around. These are long conical nosecones, and they decided since they had instrumentation in those nosecones they'd make the Jupiter nosecones the payload. But because there wasn't enough room for all the instrumentation in a Jupiter nosecone, they discontinued the conical shape until the diameter got up to 156 inches and said that's going to be the payload. Then they took the upper part of the Saturn IV-B stage, which was being built by Douglas, and put an adapter section on it at the same conical angle as the nosecone and brought that down from the 180 inches to 156 inches. That was the interface between the work going on at Douglas and the work going on at Huntsville. So when we finished our job we had a vehicle that was 14 feet in diameter and we said we'd like to fly this on top of the Saturn and they said "Oh, gee, it'll cost us a million dollars to put a new front end on the Saturn." So we went round and round, and to make a long story short we decided at Langley that it would be a lot easier just to reduce our diameter down to 156 inches than to argue with those guys. And the easiest way to do that was just to round the corners off-we didn't want to change the internal layout, so we rounded off the corners and ended up with 156 inches. Marshall decided that they would put rounded corners on Apollo and I don't think they ever knew why.

Another thing that was settled concurrently was the type of heat protection we were going to use. We certainly were going to use an ablative heat shield in front-on the blunt end coming in. There was a lot of argument on whether we should use an ablative material or shingles on the conical portion. We had used shingles on Mercury and Gemini.3 I thought we ought to use shingles on Apollo, and a lot of people thought the heating would be much worse on Apollo; it was coming in faster and we wouldn't be able to handle it with the shingles. They felt we should put ablative material back there. Well, the ablative material was definitely going to be heavier than the shingles and we were concerned about making that decision in as much as we didn't have any hard data to go on. But the thing that swayed me to the ablative material was that all of the analysis we had done up to that time showed that the occupants inside would get a pretty severe radiation dose during the mission. The additional weight would have to be included in the command module just to provide protection against solar radiation. So I thought there was very little sense to try to make the skin thinner and then have to put in a lot of weight inside to protect against this radiation. On that basis I stopped arguing with the people that wanted to put an ablative heat shield on the conical portion. I guess that was a mistake-I should have stuck by my intuition a little longer because the radiation problem wasn't near as severe as the people like Dr. Van Allen thought. He was very strong in his views that the radiation problems would be very severe. Neither situation turned out the way we designed for. The heating on the back has been very, very mild-we could have gotten by with the same kind of shingles used on Mercury and Gemini on the back. We didn't need all that material back there as protection against radiation, so perhaps we had some extra weight in the vehicle as a result.

 

How did they go about determining reliability factors for Apollo?

Nick [Nicholas E.] Golovin worked for NASA then and he had a background in mathematics. He became Mr. Reliability for NASA and proceeded to take a strong mathematical approach to reliability. His basis was that by use of proper statistical analysis you ought to be able to predict what the reliability of a system is. You do this by creating a network of all the components in the system that can fail in the proper mathematical model, and then you estimated based on experience during development, testing, etc., what individual reliability these components in this big mathematical model vehicle is. Then you just apply the proper amount of mathematical machinery to it and out comes the overall reliability. He fell very much in love with that system and there was no doubt about it, he thought it was great. I think where the engineers got a little bit uncomfortable with it was they really didn't know how you got the basic data. We thought we ought to use all of the test work up to that time. We felt the reliability performance of a system during its development phases was not much of an indication of the ultimate reliability of any component. We went round and round on this. Nevertheless, a mathematical reliability number was created for Mercury and I don't know what went with it. One of the things that happened in Apollo was everybody felt like we've done this in Mercury, and reliability never really influenced the design of Mercury, which, of course, really isn't so. It was designed to be as reliable as we could design it, but the thought was we ought to start from scratch in Apollo with some reliability goals so that the engineers would be properly motivated to reach adequate goals for reliability.

I remember early in the program I asked Walt Williams what he thought reliability ought to be for Apollo and he said, "Well, there ought to be at least three nines on safety and two nines on mission success." So we said we'd try that number. And that's the number that went in. Shortly after we'd put that number out one of the study contractors came back to me and pointed out that this wasn't very different from the expected mortality from three 40-year-old individuals on a two-week mission if you took the standard actuary tables. But anyway, that's the number we used and I guess no one can argue with the achievement.

There were two things that we made exceptions of and I think we did well on both of those. This came later in the program during the North American early development phases. One was the reliability or I guess you might say the invulnerability number to meteors, and the number with respect to radiation dose. Any analysis made during the early phase of the program-these two hazards predominated the situation. As a matter of fact, the three nines in reliability left nothing over for system failures, because all the failures were going to be from meteors or from a guy getting an overdose of radiation. What we did was essentially said the reliability model wouldn't consider these two hazards, that we would try to achieve the three nines in reliability without it and there would be added considerations. We set separate goals for meteor penetration and radiation dose and I don't remember what the goals were. We did set separate goals for those. I might say that since that time....


Members of the Apollo 204 Review Board, Astronaut Frank Borman and Max Faget (foreground), inspect the interior of an Apollo Command Module mock-up at the Kennedy Space Center on April 9, 1967, as part of the Board's investigation of the fire that took the lives of the Apollo 1 crew, Chaffee, White, and Grissom at Launch Complex 34 on January 27.

Members of the Apollo 204 Review Board, Astronaut Frank Borman and Max Faget (foreground), inspect the interior of an Apollo Command Module mock-up at the Kennedy Space Center on April 9, 1967, as part of the Board's investigation of the fire that took the lives of the Apollo 1 crew, Chaffee, White, and Grissom at Launch Complex 34 on January 27. The mock-up interior was established as closely as possible to the configuration of the 204 spacecraft before the fire. (NASA Photo 67-H-376.)


.....up until now both of the hazards from these two environments appear to be a hell of a lot less. We did a rather sensible thing.

 

On Gemini X they were still saying these hazards were going to be high.

That's right, but we had an additional problem-we were dealing with radiation outside of the Van Allen Belt and it was pretty much unexplored from the standpoint of total radiation and we had the solar storms situation where you get these great big solar events. It's very difficult to predict how severe they would be. So the whole thing was completely unmanageable from the standpoint of design engineering. We did, for a long while, carry the idea that we would provide about two-inch thick Lucite goggles for the crew because the most sensitive portion of the crew to radiation was the eyes-so in the event we got into a solar event the crew could cover their eyes with these thick Lucite goggles, Lucite having nice low density atoms that stop the radiation. But we don't carry those now, apparently the radiation hazard has decreased some more.

Another thing of big concern early in the program was whether or not to use pressure suits and what to do about personal parachutes, escape seat ejection. In both of these cases my group was recommending that we not provide these features. We made a recommendation not to use pressure suits inside the vehicle. We didn't think they were necessary and we felt that the same weight that goes into the pressure suit and the system in the vehicle to support the suit, the extra hoses, etc., could better be used in making the cabin safer. The operations people, primarily Flight Crew people and Walt Williams didn't really think that was the safe way to fly. So we designed a vehicle to be flown with the suits on all the time. Since that time we have learned through experience that suits aren't really necessary. It took the crew to decide against the suits as opposed to program management.

 

Remember the public argument on Gemini VII?

You see, in Gemini VII it was the crew that wanted to take the suits off and in Apollo it was the crew that wanted the suits on. The big voices for suits on were the crew people and Walt Williams who, of course, represented the crew to management at that time. We had a similar thing on bailout parachutes. The crew thought they would like to have chutes inside the vehicle for getting out. We went through quite an exercise on this. After North American was awarded the contract for Apollo, their original design incorporated a much larger hatch-where the quick-open door is located now-that explosively released in case of an emergency. This larger hatch spanned three couches and each crewman would have his own chute. The idea was, in the event the main parachutes weren't opening or malfunctioned, or some other trouble happened, they could blow the hatch and get out. We went through quite a few exercises with mockups trying to decide how long it would take to get out and finally decided that the cases where this would really be effective from the standpoint of saving their lives was so small that it wasn't worth carrying the system. But we did initially start off with the idea.

In addition to that, I might mention that we had a lot of design efforts that went into the landing impact system. I think the statement that was once made about how Apollo carried its landing gear inside is pretty much the case. We ended up deciding on putting the couches on shock struts and stroking the couches on impact as opposed to putting a landing bag like we had on Mercury or, in the case of Gemini-at least during the early days-we had real landing gear. I'm not so sure that was the right thing in retrospect either, but it got in there initially. It was reconsidered a number of times as different people from time to time made all sorts of arguments for some other systems. The expediency of the situation that here we had something in hand always prevailed as opposed to the cost and the schedule impact of slowing down and going with some other approach. Undoubtedly, the better thing to have done from the very start would have been to include small landing rockets. If we had it to do over again, we certainly wouldn't put the landing gear inside-we'd put landing rockets on there instead. We studied rotors, we studied gliding parachutes, we studied rockets up in the parachute riders, landing bags, all sorts of things as alternatives. Of course, we studied three parachutes, six parachutes and sequential parachutes.

I guess one of the biggest decisions made during the Apollo program was when we decided to land on the Moon. We started off with the idea that we'd build a vehicle that would be able to circumnavigate the Moon, but we always put in fine print that it would have the development potential of landing on the Moon. I think from the very start we always thought of the command module itself landing on the Moon as opposed to using the LM. It turned out, when it went out on contract for the studies-the three studies by Martin, Convair, and GE-they were all for circumnavigation. When they finally got the go ahead from the President to make a lunar landing, we had brought the program far enough along that we just amended some work statements and went out for that idea and everyone bid on an Apollo type command module actually landing on the Moon. This called for a very, very large rocket to include a landing. One of the interesting things about that thing was that the take-off rocket that was used at that time was about the same size as the service module-the same total impulse. So although at the time we actually mailed out the request for proposals we had already done enough looking into this lunar orbit rendezvous mode to realize that we could save the service module-at that time, of course, it was the return rocket, that the return rocket was the proper size for the service module. Nevertheless, when North American got under contract they thought they were contracting to build the vehicle that was actually going to land on the Moon, which proved to be a little troublesome some time later . . .

Everybody had a plan. Very early in the program we had the Goett Committee, the Low Committee, and groups in between. Near the end of the Goett Committee there was a meeting at Headquarters, prior to the time of the formation of the Low Committee that Dr. Glennan called. The thought was what to do if we want to do more than just circumnavigate the Moon or orbit the Moon. How would we go about landing on the Moon? Both Dr. Pickering and von Braun were there and this is when we were using the horizontal . . .the thing that landed on its side has basically got a lot of stability to offer as opposed to the thing trying to stand up on landing. In order to the make the landing, I showed a chart at this meeting which showed that a landing could be made in two phases; one, we'd go into orbit around the Moon and after getting into orbit we'd, two, come down from orbit to the lunar surface. Dr. von Braun questioned this right away. He said, "Well, why do you want to do it that way? We're already developing unmanned vehicles-the Surveyor in making a soft landing on the Moon, it doesn't go into orbit, it comes right straight in." Dr. Pickering got up and made a little speech about they had all the techniques worked out to that approach and you don't have to go into orbit if you want to land on the Moon. You just aim at the Moon and when you get close enough turn on the landing rockets and come straight in. I mentioned to them "that would be a pretty unhappy day if when you lit up the rockets, they didn't light." I got the feeling that this one session wasn't enough to convince them . . .

I only mention this to indicate how primitive things were at the time. There were some very well respected individuals in NASA who seriously thought we ought to go right to the Moon, and when you get about so far away from the surface, turn on the brakes and land. The advantage of going into lunar orbit . . . this kind of basic thing, had not even been considered. As a matter of fact, the outside advice was the other. The advantage of going into lunar orbit is, of course, you're not committed to anything-when you go by the Moon you have a free return, and when you do go into lunar orbit you're not committed to landing. You're only committed to landing when you've lit the final burn. The mechanics of doing it that way are basically safe and it minimizes the commitments until you're certain of the capability to do the job whereas the other approach did not. That hadn't occurred to these people prior to that time.

Like I say, the thinking at that time was very primitive and certainly explains why we had the big hullabaloo we did over LOR, EOR or direct. When we started studying the LM it was presented primarily as a method of saving weight and a method of reducing the total amount of weight. I was pretty much antagonistic toward it at first, primarily on the basis the weight estimates were in error. At that time, we needed about 120,000 to 150,000 pounds to go in direct, and to go with the LM there was less than half that much.

The earliest versions of the LM were . . . I think they weighed 2,000 lbs., and it was in that period of time that I was very concerned about whether we'd do that. Part of the problem there was we had two different groups making weight analyses. Well, I guess I did raise some objections to the LM based on the fact that I thought the people trying to sell it hadn't done a very good job on....


For the work done in this area, NASA received an Emmy Award from the National Academy of Television Arts and Sciences. Shown here is Faget accepting the award on behalf of NASA on June 29, 1970.

During the Apollo program, one of the projects Max Faget directed was the lunar communications relay unit and ground command television assembly used for the first time on the Apollo 15 lunar landing mission. This equipment greatly improved communications between the Earth and the Moon and allowed people around the world to watch the lunar excursions real-time on their televisions. For the work done in this area, NASA received an Emmy Award from the National Academy of Television Arts and Sciences. Shown here is Faget accepting the award on behalf of NASA on June 29, 1970. (NASA Photo 70-44081.)


....estimating what it weighed. When it came down to really doing the job there was no doubt about it, the best thing about the LM was that it allowed us to build a separate vehicle for landing-it didn't have anything to do with lighter or heavier . . .

The decision was made that the approach that MSC [Manned Spacecraft Center] initially wanted to take was to go "doll up" mode, so called, where we would build a Saturn that would lift 120,000-150,000 pounds. With that size Saturn, we felt we could land a command and service module itself right on the Moon, which would put all three people on the Moon . . . we thought that's the way to do it. It also had the advantage that if we were doing that now and wanted to stay a week we'd have no trouble staying that long. We started down that path and the first thing that happened was that we had the Golovin Committee get involved in designing the next program boosters. We got Huntsville . . . I forget how this all worked out but we ended up with a five engine Saturn instead of an eight engine Saturn. Wernher [von Braun] first backed off from eight engines to four engines on the basis that this was as big as he could build it. Then he ended up putting that middle engine in there because it seemed like it would fill up the hole . . . Nevertheless, the stated reason we couldn't build an eight engine Saturn was that we were going to build it at Michoud [Michoud Assembly Facility at New Orleans, Louisiana], and the biggest tank they could build at Michoud was 33 feet in diameter, and that went with five engines, not eight. If we wanted to go to eight engines, it had to be something like 36 or 38 feet in diameter. It just wouldn't fit without raising the roof at Michoud. I think they basically wanted to do earth orbit rendezvous at Marshall, and they felt the best way to get the smarts to do that was to make sure the booster didn't get so big they didn't have to. That's dirty thinking I guess, but I really think that motivated them a hell of a lot-they said "well why should we worry about making it so big, we can always do earth orbit rendezvous." What came out of all this high-powered planning was that we would build a five-engine Saturn, and we would have earth orbit rendezvous. That was the way NASA started down the line and, of course, that's the way North American started off on the contract.

In the case of actually doing earth orbit rendezvous two problems came up, one was do you do earth orbit rendezvous by fuel transfer or do you do earth orbit rendezvous by actually hooking things together in earth orbit. As far as I know, that problem never got solved. Every time you'd tell them what was wrong with one way of doing it they'd tell you well they were going to do it the other way. The business of rendezvousing in earth orbit was not the problem, but the business of after you rendezvous in earth orbit how do you put together the wherewithal to go to the Moon. That was the problem, and that problem was never solved.

There was another thing that bothered us, at least it bothered me, and that was we really started off designing a vehicle to do lunar orbit. In order to make that thing land on the Moon, the original plan had to make the landing stage use hydrogen-oxygen propulsion and RL-10 rocket engines. The RL-10 had already demonstrated that it could be throttled . . .

It turned out that the decision was to give the Lewis Laboratory the landing stage for Apollo, and . . . I didn't think a hell of a lot of it . . . it meant that instead of two Centers doing the Apollo program it would be three Centers. I always felt that the landing stage would be a pretty intimate part of the vehicle. The interface between the landing stage and the rest of the vehicle was a lot more intimate than the interface between spacecraft and launch vehicles. It was a much more intimate interface that we were going to have to make two Centers work on. So, after looking at the problems in this thing, the crew would have to . . . well, you had all the landing dynamics, the landing gear, the flight control right down to the lunar surface, and all that . . . it looked like it would be a big thing. We did some more studying and we were able to show that if you really wanted to land on the Moon it probably would be better to separate from the hydrogen-oxygen system just before you land, and land on a real short stage. This had to do with the height of the landing stage and a bunch of other things. So we generated what we called the lunar crasher concept, which meant there was a hydrogen-oxygen stage that was used first to get into lunar orbit and second to descend to a couple of thousand feet above the surface of the Moon, and then you go into the hover mode, or the throttle down mode. At that time, we jettison the hydrogen-oxygen stage and lit an earth storable propellant landing stage using the same kind of propellants we now use to land. The vehicle that actually lands is a lot more compact and would have all of the good features that you obtain by a pressure fed storable system. It also had the added benefit, at least to us, of greatly simplifying the interface because then we could consider the hydrogen-oxygen stage like just another launch stage. It didn't play as intimate a role into the maneuvers . . . it didn't have the landing gear and all those things that interact with the rest of the vehicle as deeply as that would. So we went to Headquarters and argued long and hard for the lunar crasher, and as a matter of fact we did sell the concept. Lewis was then under direction to build the lunar crasher stage, and we were going to have North American build the lunar lander portion. I really didn't like the idea of earth orbital rendezvous. Not liking earth orbit rendezvous was one of the things that made lunar orbit rendezvous look very attractive. It got rid of a hell of a lot of problems that you can see were being generated.

 

I've heard it said that you were the second man who was ready to go LOR. I think I'm beginning to see the reason.

I think that Bob Piland and Kemble Johnson were against it. Gilruth told us one day, "We really ought to study that real good." No doubt about it, he had a lot of influence on it, but we started perceiving these other problems, the problems of earth orbit rendezvous, and the problems of the lunar crasher, and the interface with Lewis. Boy, lunar orbit rendezvous really looked like the thing to do. In addition, it did get us out of a very difficult thing which we never solved, which was how in the world were we going to fly that command module down to the surface of the Moon. We had all sorts of little ideas about hanging porches on the command module, and periscopes, and TVs, and other things, but the business of eyeballing that thing down to the Moon didn't really have a satisfactory answer . . . No doubt about it, we'd have had to put a porch on that damn thing so the guy could sit up there and look, and once we'd provided him with that I think we could have gotten it down, but it would have had a lot more complications. And of course in the case of the command module, it would have been way up there-we'd have had to put a long ladder down. It would have taken quite a ladder. But, we would have ended up with three guys on the Moon.

 

Interview #1

There were two episodes in Apollo which were calamities, one of them not so much as the other. The first one, the Apollo fire on the pad, what happened there? What was the pressure inside NASA that created the need to move into the program with a Block I spacecraft that you knew was not going to be the flight model, the full flight model? What caused that particular circumstance to develop?

 

Well, we had Block I and Block II. Block I was in manufacturing long before Block II was, obviously because it was I instead of II, and it was getting close to completion, and it just made sense to go ahead and fly it instead of waiting for Block II, because you had to make progress. There were a lot of things wrong with Block I, but the main thing that was wrong with Block I was not something that was anticipated in Block II, namely that there was too much flammable material aboard [and] that we didn't properly recognize how fast a fire would propagate and that there was not a way to get out. In other words, this hatch couldn't be done from the inside. Once the pressure started building up, it was glued in there.

 

In a pure oxygen atmosphere.

Yes. Hindsight is wonderful. We had the same atmosphere in Mercury and Gemini as we had in Apollo. They never had any fires. But, you see, after I started thinking about it, kicking myself for being so stupid, I realized that the difference between Mercury and Apollo was that one Apollo experience was probably equivalent to maybe 20 or 30 Mercurys, simply because there's so much more volume in Apollo and there's so much more stuff in Apollo, so that it's going to burn just as badly. It only takes a teeny bit of stuff, with some teeny bit of flammable material to ruin the whole thing, but there's so much less material in Mercury and so much less in Gemini, actually, than Apollo, that the odds of it happening in Apollo-you'd say, well, sooner or later it would have happened in one of the Apollo flights. It just happened to happen on this one.

As you probably know, I was on the review board after the fire. We never did find out what caused it, what specifically caused it, but the real reason it happened is that we had too much flammable material in there and we had a completely pure oxygen atmosphere. Now, one of the things that resulted from that is, we worked on both. We had a very extensive program where we actually tested the flammability of everything that went in there, and we coated items with nonflammable stuff.

Did you know we came to an impasse, though? We found out that we could not completely be assured that we would not have a fire, in spite of all the changes we made to the material, and that's simply because we had an atmosphere which was about a half a pound of pressure greater than sea level of just pure oxygen in there. You say, well, why did we have the oxygen atmosphere in there? Well, it's a complicated story, but it's one that we're pretty much trapped in. It all gets down to the fact that we wanted to be able to go in and out of this vehicle in a spacesuit at any time without any pre-breathing, so we could not afford to have any nitrogen in the air if we were going to get the man down to possibly three psi, which is the lowest pressure that you might end up with when you go out in a suit. It doesn't take very much nitrogen in the atmosphere to give you the bends, if that's what happens. So we start off with the oxygen.

Well, I got to thinking about this, and I said, well, you know, you're not going to go out in a suit for a couple of days after we launch. So we went to what we call the 60-40 atmosphere, which would solve the problem. Just putting that much dilution into the atmosphere, 40 percent nitrogen, greatly reduced the flammability of a lot of things that we just couldn't make inflammable in tests . . .

I think Block II probably would have been just about as flammable as Block I. Now, there were other things that were not good in that spacecraft when you looked at it. The wiring was not too well done. It was not neatly done. There were too many fixes and so forth in the wiring. Where they found something wrong with the electrical service, they'd tape over or jump over it. A lot of circuits were added later on that weren't anticipated, which made for junky wire bundles. Obviously neatness is an important thing when you think about fire hazards. The spacecraft itself was not too neat in Block I as a concept, and all this was cleaned up in Block II.

 

Do you feel, in hindsight, that the agency was pushing too fast in getting ready to fly the Block I spacecraft?

No. I didn't think so. If they'd said, "Relax, take another three or four months," we'd still have probably flown the same spacecraft, still would probably have run the same tests, still probably had the same goddamned fire. If we had waited until Block II, it might have been a little cleaner, but I'm not sure. There was an awful lot of stuff in there. They were using Velcro all over the place and they were patching up. Papers were here and papers there. It was just a relaxed attitude towards fire, which was not called for.

Now, we gave Rockwell the title of "fire marshal," you know, which is kind of like the guy who comes in the theater and looks around and says, "No, you can't have people in here. You've got this, that, and the other you've got to do before I'll allow this auditorium to be occupied by a big crowd." They had not done that yet. I'm sure they were going to do it, and, probably, given enough time, they probably would have done it, but I don't think it was high on their priority list.

 

What was the biggest challenge to Apollo?

The biggest challenge to Apollo, I really think was propulsion. When astronauts are in Earth orbit, they can come down so easy because all they've got to do is slow down a little bit, and they're going to come back into the atmosphere, and once a vehicle has been through an entry aerodynamically and you know it's controllable, you don't worry about it burning up. But when you're on the Moon, you're in a gravity sink. Your propulsion system has got to work. It has really got to work. You can't wish your way out of that sink. [Laughter] You know, being in lunar orbit's one thing. You've got to come up with something like 2,000 or 3,000 feet a second to get out. On the surface, you've got to come up with a lot more than....


This early illustration shows a concept for Apollo which would have employed either the direct ascent or Earth orbital rendezvous mode of operation.

This early illustration shows a concept for Apollo which would have employed either the direct ascent or Earth orbital rendezvous mode of operation. Shown here is the all-up configuration which allowed three astronauts to travel to the surface of the Moon for up to a week's stay and return using a single spacecraft. Note the towering height of the vehicle, its return upper stage and the now familiar command module which the crew would have used for their return to Earth once the upper return stage vehicle blasted off from the lunar surface. (Photo courtesy NASA.)


....that to get out, and, of course, you've got to get up and make the precision of the rendezvous.

What you would call the mission analysis guys had to do a lot to make sure that they could abort anytime during the descent and still rendezvous. We carried a lot of propellant aboard for contingencies, and as we developed the flights and began to better understand, we gave up a lot of that contingency capability because we realized it wasn't necessary.

When we first started thinking about the lunar program, the question was how much propellant did you have to have to correct for navigation errors [on the way out and during the return], how much spare propellant? If you make an error, the only way you can correct the error is to change the velocity, and the bigger the error, of course, the bigger the change in velocity. We were carrying something like 500 feet a second of propellant, just reserve propellant for errors in the first analysis of the lunar mission. By the time we actually got to flying, we were down to maybe 100 feet a second. I think on some of the last flights we used maybe two or three feet a second on the way back from the Moon to correct errors. [Laughter]

What you find out is that you can really track good and you can detect error when you're at the Moon. Say you've got a tenth-of-a-foot-a-second error at the Moon. If you don't correct that, by the time you get maybe a half an hour from hitting the atmosphere on Earth, that tenth of a foot a second could be twenty feet a second in correction that you'd need. So as our tracking capability improved, we could detect errors early, correct them early, and correct them with assurance. It's not that we were just burning propellant because we think there's something wrong; we know what to do, we know how much to correct. You really don't have to carry all that contingency.


ENDNOTES

1. Several other members of what would become NASA's Space Task Group also attended Louisiana State University. Paul Purser earned a B.S. degree in aeronautical engineering from LSU in 1939 and worked briefly for the Martin Company in Baltimore, before joining Langley that same year. Joseph G. "Guy" Thibodaux and Max Faget were college roommates and both graduated in 1943. In looking back on those days, Thibodaux recalls "The interesting part of it is that Paul Purser, Max Faget, and I were all LSU graduates. Max and I were college roommates. We (Max and I) had a pact that at the end of the war, if we both survived, we'd get together and go look for a job together." Excerpt from an interview with Guy Thibodaux conducted on September 9, 1996, as part of "Space Stories: Oral Histories from the Pioneers of America's Space Program," an oral history project conducted in conjunction with the Houston Chapter of the [377] AIAA and Honeywell Corporation. The interviews were conducted by Robbie Davis-Floyd and Kenneth J. Cox.

2. On September 9, 1959, at 08:19 UT, the first major test of the Mercury program began when an early production Atlas D was launched from Cape Canaveral carrying a boilerplate spacecraft 95 miles into space and 1,496 miles down the Atlantic Missile Range in a 13 minute flight. Programmed to reach a speed of 16,800 mph and throw the Mercury spacecraft 2,000 miles downrange, the two Atlas booster motors failed to separate at 2 minutes into the flight and, encumbered by the additional weight, the vehicle achieved a speed of only 14,857 mph. The spacecraft experienced 12 g during reentry, and when it was recovered the next day, inspection of the shielding revealed that less than 30 percent of the ablative material had eroded, despite higher-than-planned-for temperatures during reentry.

3. The shingles used on Mercury and Gemini were made of Inconel-X, a nickel-chrome alloy. This material had been previously used with great success on the X-15 program as it was "capable of rapid heating to high temperature (1200 F) without developing high thermal stresses, or thermal bucking, and without appreciable loss of strength or stiffness." Loyd S. Swenson, Jr., James M. Grimwood, and Charles C. Alexander, This New Ocean: A History of Project Mercury, NASA SP-4201, GPO 1962, pp. 57, 63.


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