Saturn I through Saturn V, 1958-75
Soon after the engineers at Wallops began developing Scout, those at the Redstone Arsenal started work on the Saturn family of launch vehicles. Whereas the solid-propellant Scout was the runt among American launch vehicles, the liquid-fueled Saturn became the giant. The standard Scout at the end of its career was a four-stage vehicle about 75 feet in height, but the Saturn V, with only three stages, stood almost 5 times as tall, about 363 feet. This made the Saturn taller than the Statue of Liberty—equivalent in height to a 36-story building and taller than a football field was long. Composed of some 5 million parts, it was a complex mass of propellant tanks, engines, plumbing fixtures, guidance/control devices, thrust structures, and other elements. Its electrical components, for example, included some 5,000 transistors and diodes, all of which had to be tested both individually and in conjunction with the rest of the vehicle to ensure that they would work properly when called upon. The Scout could launch only 454 pounds into a 300-mile orbit, but the Saturn V sent a roughly 95,000-pound payload with three astronauts on board toward six successful lunar orbits.64
Using clustering of rocket engines in its lower stages to achieve its massive initial thrust, the Saturn V was based on the earlier development of vehicles that ultimately came to be designated the Saturn I and the Saturn IB. These two interim space boosters were, in turn, based upon technologies developed for the Redstone, Jupiter, Thor, Atlas, Centaur, and other vehicles and stages. Thus, although the Saturn family constituted the first group of rockets developed specifically for launching humans into space, it did not so much entail new technologies as it did a scaling up in size of 74 existing or already developing technology and an uprating of engine Chapter 2 performance. Even so, this posed significant technological hurdles and, often, a need to resort to empirical solutions to problems they raised. Existing theory and practice were inadequate for both the massive scale of the Saturns and the need to make them sufficiently reliable to carry human beings to an escape trajectory from Earth’s immediate vicinity out toward the Moon.65
The organization under Wernher von Braun at the Army Ballistic Missile Agency (ABMA)—which became NASA’s Marshall Space Flight Center (MSFC) in mid-1960—began the initial research and
development of the Saturn family of vehicles. In response to DoD projections of a need for a very large booster for communication and weather satellites and space probes, ABMA had begun in April 1957 to study a vehicle with 1.5 million pounds of thrust in its first stage. Then the formation of the Advanced Research Projects Agency (ARPA) on February 7, 1958, led ABMA to shift from initial plans to use engines still under development. Despite the crisis resulting from Sputnik, ARPA urged the use of existing and proven engines so that the new booster could be developed as quickly as possible at a minimal cost. ABMA then shifted to use of eight uprated Thor – Jupiter engines in a cluster to provide the 1.5 million pounds of thrust in the first stage, calling the new concept the Juno V. This led to an ARPA order on August 15, 1958, initiating what von Braun and others soon started calling the Saturn program, a name ARPA officially sanctioned on February 3, 1959.66
Under a contract signed on September 11, 1958, the Rocketdyne Division of North American Aviation in fact supplied an H-1 engine that was actually more than an uprated Thor-Jupiter powerplant. It resulted from research and development on an X-1 engine that the Experimental Engines Group at Rocketdyne began in 1957. Meanwhile, the engineers at ABMA did some scrounging in their stock of leftover components to meet the demands of ARPA’s schedule within their limited budget. The schedule called for a full-scale, static firing of a 1.5-million-pound cluster by the end of 1959. Instead of a new, single tank for the first stage, which would have required revised techniques and equipment, the ABMA engineers found rejected or incomplete 5.89-foot (in diameter) Redstone and 8.83-foot Jupiter propellant tanks. They combined one of the Jupiter tanks with eight from the Redstone to provide a cluster of propellant reservoirs for the first-stage engines. In such a fashion, the Saturn program got started, with funding gradually increased even before the transfer of the von Braun group to NASA.67
Initially called the Saturn C-1, the Saturn I (properly so-called after February 1963) was at first going to have a third stage, but between January and March 1961, NASA decided to drop the third stage and to use Pratt & Whitney RL10 engines in the second stage. These were the same engines being developed for Centaur. Meanwhile, on April 26, 1960, NASA had awarded a contract to the Douglas Aircraft Company to develop the Saturn I second stage, which confusingly was called the S-IV. Unlike the Centaur, which used only two RL10s, the S-IV held six of the engines, requiring considerable scaling up of the staging hardware. Using its own experience as well as cooperation from Centaur contractors Convair and Pratt &
Whitney, Douglas succeeded in providing an SL-IV stage in time for the January 29, 1964, first launch of a Saturn I featuring a live second stage. This was also the first launch with 188,000-pound – thrust H-1 engines in the first stage, and it succeeded in orbiting the second stage.68
Development of the Saturn I posed problems. Combustion instability in the H-1 engines, stripped gears in an H-1 turbopump, sloshing in first-stage propellant tanks, and an explosion during static testing of the S-IV stage all required redesigns. But apart from the sloshing on the first Saturn I launch (SA-1), the 10 flights of Saturn I (from October 27, 1961, to July 30, 1965) revealed few problems. There were changes resulting from flight testing, but NASA counted all 10 flights successful, a tribute to the thoroughness and extensive ground testing of von Braun’s engineers and their contractors.69
At 191.5 feet tall (including the payload), Saturn I was still a far cry from Saturn V. The intermediate version, Saturn IB, consisted of a modified Saturn I with its two stages (S-IB and S-IVB) redesigned to reflect the increasing demands placed upon them, plus a further developed instrument unit with a new computer and additional flexibility and reliability. The S-IVB would serve as the second stage of the Saturn IB and (with further modifications) the third stage of the Saturn V, exemplifying the building-block nature of the development process. The first stage of the Saturn IB was also a modified S-I, built by the same contractor, Chrysler. The cluster pattern for the eight H-1 engines did not change, although uprating increased their thrust to 200,000 and then 205,000 pounds per engine. In its second stage, the Saturn IB had a new and much larger engine, the J-2, with thrust exceeding that of the six RL10s used on the Saturn I. Like the RL10s, it burned liquid hydrogen and liquid oxygen.70
Rocketdyne won a contract (signed on September 10, 1960) to develop the J-2, with specifications that the engine ensure safety for human flight yet have a conservative design to speed up availability. By the end of 1961, it had become evident that the engine 76 would power not only stage two of Saturn IB but both the second Chapter 2 and third stages of the Saturn V. In the second stage of Saturn V, there would be a cluster of five J-2s; on the S-IVB second stage of Saturn IB and the S-IVB third stage of Saturn V, there would be a single J-2 a piece. Rocketdyne engineers had problems with injectors for the new engine until they borrowed technology from the RL10, a further example of shared information between competing contractors, facilitated by NASA.71
After completion of its development, the Saturn IB stood 224 feet high. Its initial launch on February 26, 1966, marked the first flight
tests of an S-IVB stage, a J-2 engine, and a powered Apollo spacecraft. It tested two stages of the launch vehicle plus the reentry heat shield of the spacecraft. Except for minor glitches like failures of two parachutes for data cameras, it proved successful. Other flights also succeeded, but on January 27, 1967, a ground checkout of the vehicle for what would have been the fourth flight test led to the disastrous Apollo fire that killed three astronauts. The test flights of Saturn IB concluded with the successful launching and operation of the command and service modules (CSM), redesigned since the fire. Launched on October 11, 1968, the Saturn IB with a 225,000-pound – thrust J-2 in the second stage performed well in this first piloted Apollo flight. This ended the Saturn IB flights for Apollo, although the vehicle would go on to be used in the Skylab and Apollo-Soyuz Test Projects from 1973 to 1975.72
Development of some parts used exclusively for the Saturn V began before design of other components common to both the Saturn IB and the Saturn V. For instance, on January 9, 1959, Rocketdyne won the contract for the huge F-1 engine used on the Saturn V (but not the IB); however, not until May 1960 did NASA select Rocket – dyne to negotiate a contract for the J-2 common to both launch vehicles. Configurations were in flux in the early years, and NASA did not officially announce the C-1B as a two-stage vehicle for Earth – orbital missions with astronauts aboard until July 11, 1962, renaming it the Saturn IB the next February. (NASA Headquarters had already formally approved the C-5 on January 25, 1962.) Thus, even though the Saturn IB served as an interim configuration between the Saturn I and the Saturn V, development of both vehicles overlapped substantially, with planning for the ultimate moon rocket occurring even before designers got approval to develop the interim configuration.73
Burning RP-1 as its fuel with liquid oxygen as the oxidizer, the F-1 did not break new technological ground—in keeping with NASA guidelines to use proven propellants. But its thrust level required so much scaling up of the engine as to mark a major advance in the state of the art of rocket making. Perhaps the most intricate design feature of the F-1, and certainly one that caused great difficulty to engineers, was the injection system. As with many other engines, combustion instability was the problem. On June 28, 1962, during an F-1 hot-engine test at the rocket site on Edwards AFB, combustion instability led to the meltdown of the engine. Using essentially trial-and-error methods coupled with high-speed instrumentation and careful analysis, a team of engineers had to test perhaps 40 or 50 design modifications before they eventually found a combination of
baffles, enlarged fuel-injection orifices, and changed impingement angles that worked.74
Despite all the effort that went into the injector design, according to Roger Bilstein, it was the turbopump that “absorbed more design effort and time for fabrication than any other component of the engine." There were 11 failures of the system during the development period. All of them necessitated redesign or a change in manufacturing procedures. The final turbopump design provided the speed and high volumes needed for a 1.5-million-pound-thrust engine with a minimal number of parts and high ultimate reliability. However, these virtues came at the expense of much testing and frustration.75
There were many other engineering challenges during design and development of the Saturn V. This was especially true of the S-II second stage built by the Space and Information Systems Division of North American Aviation. Problems with that segment of the huge rocket delayed the first launch of the Saturn V from August until November 9, 1967. But on that day the launch of Apollo 4 (flight AS-501) without astronauts aboard occurred nearly without a flaw.76
After several problems on the second Saturn V launch (including the pogo effect on the F-1 engines) prevented the mission from being a complete technical success, engineers found solutions. As a result, the third Saturn V mission (AS-503, or Apollo 8) achieved a successful circumlunar flight with astronauts aboard in late 1968. Following two other successful missions, the Apollo 11 mission between July 16, 1969, and July 24, 1969, achieved the first of six successful lunar landings with the astronauts returning to Earth, fulfilling the goals of the Apollo program.77
With Saturns I and IB as interim steps, Saturn V was the culmination of the rocket development work von Braun’s engineers had been carrying on since the early 1930s in Germany. In the interim, the specific engineers working under the German American baron 78 had included a great many Americans. There had been a continual Chapter 2 improvement of technologies from the V-2 through the Redstone, Jupiter, and Pershing missiles to the three Saturn launch vehicles.
Not all of the technologies used on Saturn V came from von Braun’s engineers, of course. Many technologies in the Saturn V resulted from those developed on other programs in which von Braun’s team had not participated or for which it was only partly responsible. This is notably true of much liquid-hydrogen technology, which stemmed from contributions by Lewis Research Center, Convair, Pratt & Whitney, Rocketdyne, and Douglas, among
others—showing the cumulative effects of much information sharing. But Marshall engineers worked closely with the contractors for the J-2, S-II, and S-IVB stages in overcoming difficulties and made real contributions of their own. This was also true in the development of the Saturn engines. Rocketdyne had started its illustrious career in engine development by examining a V-2 and had worked with von Braun and his engineers on the Redstone engine, a process that continued through Jupiter and the Saturn engines. But a great many of the innovations that led to the F-1 and J-2 had come more or less independently from Rocketdyne engineers, and even on the major combustion-instability and injector problems for the F-1, Rocketdyne’s contributions seem to have been at least as great as those from Marshall engineers. In other words, it took teamwork, not only among Americans and Germans at Marshall but among Marshall, other NASA centers, industry, universities, and the U. S. military to create the Apollo launch vehicles. Air force facilities and engineers at Edwards AFB, Holloman AFB, and the Arnold Engineering Development Center also made key contributions to facets of Saturn development.
Another key ingredient in the success of Saturn rocket development was the management system used at ABMA and the NASA Marshall Space Flight Center. As at Peenemunde, von Braun retained his role as an overall systems engineer despite other commitments on his time. At frequent meetings he chaired, he continued to display his uncanny ability to grasp technical details and explain them in terms everyone could understand. Yet he avoided monopolizing the sessions, helping everyone to feel part of the team. Another technique to foster communication among key technical people was his use of weekly notes. Before each Monday, he required his project managers and laboratory chiefs to submit one-page summaries of the previous week’s developments and problems. Each manager had to gather and condense the information. Then von Braun wrote marginal comments and circulated copies back to the managers. He might suggest a meeting between two individuals to solve a problem or himself offer a solution. Reportedly, the roughly 35 managers were eager to read these notes, which kept them all informed about problems and issues and allowed them to stay abreast of overall developments, not just those in their separate areas. In this way, the notes integrated related development efforts and spurred efforts to solve problems across disciplinary and organizational lines.78
Superficially, these “Monday notes" seemed quite different from Schriever’s “Black Saturdays" and Raborn’s PERT system. They
were certainly less formal and more focused on purely technical solutions than on cost control. But in the technical arena, von Braun’s system served the same systems-engineering function as the other systems.
While the Saturn I was undergoing development and flight testing, significant management changes occurred in NASA as a whole. From November 18, 1959 (when NASA assumed technical direction of the Saturn effort), through March 16, 1960 (when the space agency took over administrative direction of the project and formal transfer took place), to July 1, 1960 (when both the Saturn program and the von Braun team of engineers transferred to the Marshall Space Flight Center), the administrator of NASA remained the capable and forceful but conservative T. Keith Glennan. Glennan had organized NASA, adding JPL and Marshall to the core centers inherited from the National Advisory Committee for Aeronautics, NASA’s predecessor.79
Once John F. Kennedy became president in early 1961 and appointed the still more forceful and energetic but hardly conservative James E. Webb to succeed Glennan, there were bound to be management changes. This was further ensured by Kennedy’s famous exhortation on May 25, 1961, “that this nation. . . commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to earth." The commitment that followed gave an entirely new urgency to the Saturn program. To coordinate it and the other aspects of the Apollo program, NASA reorganized in November 1961. Even before the reorganization, Webb chose as head of a new Office of Manned Space Flight (OMSF) an engineer with Radio Corporation of America who had been project manager for the Ballistic Missile Early Warning System (BMEWS). D. Brainerd Holmes had finished the huge BMEWS project on time and within budget, so he seemed an ideal person to achieve a similar miracle with Apollo.80
Holmes headed one of four new program offices in the reorga – 80 nized NASA Headquarters, with all program and center directors Chapter 2 now reporting to Associate Administrator Robert C. Seamans Jr., who also took over control of NASA’s budget. Webb apparently had not fully grasped Holmes’s character when he appointed him. The second NASA administrator had previously considered Abe Sil – verstein to head OMSF and rejected him because he wanted too much authority, especially vis-a-vis Seamans. Holmes, however, turned out to be “masterful, abrasive, and determined to get what he needed to carry out his assignment, even at the expense of other programs." Within two weeks of joining NASA, the confrontational
Wernher von Braun (center) showing the Saturn launch system to Pres. John F. Kennedy and Deputy NASA Administrator Robert Seamans (left) at Cape Canaveral, November 16, 1963. (Photo courtesy of NASA)
as unlikely that a lunar landing could be achieved during Kennedy’s decade “with acceptable risk." They believed it would be late 1971 before a landing could occur. Mueller took the two men to Seamans’s office to repeat the findings. Seamans then told Mueller privately to find out how to get back on schedule, exactly the authority and leverage Mueller had evidently sought.83
On November 1, 1963, Mueller then instituted two major changes that offered a way to land on the Moon by the end of the decade and greatly strengthened his position. One change was all-up testing. In 1971 Mueller claimed he had been involved with the development of all-up testing at Space Technology Laboratories, although he may or may not have known that his organization had opposed the idea when Otto Glasser introduced it as the only way he could conceive to cut a year from development time for Minuteman at the insistence of the secretary of the air force. In any event, all-up testing had worked for Minuteman and obviously offered a way to speed up testing for the Saturn vehicles.84
NASA defined all-up testing to mean a vehicle was “as complete as practicable for each flight, so. . . a maximum amount of test information is obtained with a minimum number of flights." This conflicted with the step-by-step procedures preferred by the von Braun group, but on November 1, Mueller sent a priority message to Marshall, the Manned Spacecraft Center (MSC) in Houston, and the Launch Operations Center (LOC) in Florida. In it he announced a deletion of previously planned Saturn I launches with astronauts aboard and directed that the first Saturn IB launch, SA-201, and the first Saturn V flight, AS-501, should use “all live stages" and include “complete spacecraft." In a memorandum dated October 26, 1963, Mueller wrote to Webb via Seamans, enclosing a proposed NASA press release about all-up testing: “We have discussed this course of action with MSFC, MSC, and LOC, and the Directors of these Centers concur with this recommendation," referring specifically to eliminating “manned" Saturn I flights but by implication, 82 to the all-up testing. The press release stated that “experience in Chapter 2 other missile and space programs" had shown it to be “the quickest way of reaching final mission objectives" (a further example of how shared information was important to missile and launch-vehicle programs).85
If Mueller had really discussed all-up testing with the center directors, this was not apparent at Marshall, where von Braun went over the message with his staff on November 4, creating a “furor." Staff members recalled numerous failed launches in the V-2, Redstone, and Jupiter programs. William A. Mrazek believed the idea
of all-up testing was insane; other lab heads and project managers called it “impossible" and a “dangerous idea." Although von Braun and his deputy, Eberhard Rees, both had their doubts about the idea, in the end they had to agree with Mueller that the planned launches of individual stages would prevent landing on the Moon by the end of the decade. All-up testing prevailed despite von Braun’s doubts.86 And once again, it worked.
The second change introduced on November 1 entailed a reorganization of NASA, placing the field centers under the program offices once again, rather than under Seamans. Mueller obtained authority over Marshall, the MSC, and the LOC (renamed Kennedy Space Center in December).87
One aspect of the Marshall effort that did not fit with Mueller’s management concepts was the proclivity for technical decisions in Huntsville to be based on their merits instead of schedule or cost. This was true even though project managers were supposed to get jobs done “on time and within budget." A concern with time, budget, and what had come to be called configuration control, however, had become very important in the Minuteman program and quickly spread to NASA when Mueller arranged for Brig. Gen. Samuel Phillips to come to NASA as deputy director and then director (after October 1964) of the Apollo program. The slender, handsome Phillips had moved from his post as director of the Minuteman program in August 1963 to become vice commander of the Ballistic Systems Division. He arrived at NASA Headquarters in early January 1964 and soon arranged for the issue in May of a NASA Apollo Configuration Management Manual, adapted from an air force manual.88
Phillips had expected resistance to configuration management from NASA. He was not disappointed. Mueller had formed an Apollo Executive Group consisting of the chief executives of firms working on Apollo plus directors of NASA field centers, and in June 1964, Phillips and a subordinate who managed configuration control for him presented the system to the assembled dignitaries. Von Braun objected to the premises of Phillips’s presentation on the ground that costs for development programs were “very much unknown, and configuration management does not help." He contended that it was impossible for the chairman of a configuration control board to know enough about all the disciplines involved to decide intelligently about a given issue. Phillips argued that if managers were doing their jobs, they were already making such decisions.
Von Braun retorted that the system tended to move decisions higher in the chain of management. William M. Allen of Boeing countered that this was “a fundamental of good management." When von
Braun continued to argue the need for flexibility, Mueller explained that configuration management did not mean that engineers had “to define the final configuration in the first instance before [they knew] that the end item [was] going to work." It meant defining the expected design “at each stage of the game" and then letting everyone know when it had to be changed. Center directors like von Braun did not prevail in this argument, but resistance continued in industry as well as NASA centers, with the system not firmly established until about the end of 1966.89
Mueller and Phillips introduced other management procedures and infrastructure to ensure control of costs and schedules. Phillips converted from a system in which data from the field centers came to Headquarters monthly to one with daily updates. He quickly contracted for a control room in NASA Headquarters similar to the one he had used for Minuteman, with data links to field centers. A computerized system stored and retrieved the data about parts, costs, and failures. Part of this system was a NASA version of the navy’s Program Evaluation and Review Technique (PERT), developed for Polaris, which most prime contractors had to use for reporting cost and scheduling data.90
Despite von Braun’s resistance to configuration management, Phillips recalled in 1988, “I never had a single moment of problem with the Marshall Space Flight Center. [Its] teamwork, cooperation, enthusiasm, and energy of participation were outstanding." Phillips added, “Wernher directed his organization very efficiently and participated in management decisions. When a decision had been made, he implemented it—complied, if you will, with directives." In part, no doubt, Phillips was seeing through the rose-colored glasses of memory. But in part, this reflected von Braun’s propensity to argue until he was either convinced that the contrary point of view was correct or until he saw that argument was futile. Then he became a team player.
Phillips had been at the receiving end of V-2s in England during 84 World War II, and he was prepared to dislike the German baron who Chapter 2 had directed their development. But the two became friends. He commented that von Braun “could make a person feel personally important to him and that [his or her] ideas were of great value." When asked about von Braun’s contributions to the space program, Phillips observed that a few years before, he probably would have said that American industry and engineering could have landed on the Moon without German input. But in 1988 he said, “When I think of the Saturn V, which was done so well under Wernher’s direction and which was obviously. . . essential to the lunar mis-
sion, . . . I’m not sure today that we could have built it without the ingenuity of Wernher and his team."91
The contributions of Mueller and Phillips were probably more critical to the ultimate success of Apollo than even von Braun’s. Phillips hesitated about characterizing Mueller but did say that “his perceptiveness and ability to make the right decision on important and far-reaching [as well as] complex technical matters" was “pretty unusual." On the other hand, Mueller’s biggest shortcoming, according to Phillips, was “dealing with people." John Disher, who admired Silverstein but characterized Mueller as the “only bona – fide genius I’ve ever worked with," had to observe that although his boss was “always the epitome of politeness, . . . deep down he [was] just as hard as steel." Also, human space program director of flight operations, Chris Kraft, who dealt with a great many people and frequently clashed with Mueller, had to say that “I’ve never dealt with a more capable man in terms of his technical ability." Difficult though Mueller was, without him and Phillips, American astronauts probably would not have gotten to the Moon before the end of the decade.92
Both men brought to NASA some of the culture and many of the management concepts used in the air force, plus the navy’s PERT system. These added to the amalgam of cultures already present in the space agency. Inherited from the National Advisory Committee for Aeronautics (NACA) was a heavy research orientation coupled with a strong emphasis on testing. Von Braun’s Germans had brought a similar culture from their V-2 and army experience, together with a tendency to over-engineer rocket systems to ensure against failure. JPL had added its own blend of innovation plus a strong reliance on theory and use of mathematics that was also part of the V-2 experience. The Lewis Research Center brought to the mix its experience with liquid hydrogen, and the Langley Research Center brought the testing of rockets at Wallops Island and a wind – tunnel culture (present also at Ames Research Center). All of these elements (and the management styles that accompanied them) contributed to the Saturn-Apollo effort.