The Saturn I was a rocket designed as the United States' first medium lift launch vehicle for up to low Earth orbit payloads.Terminology has changed since the 1960s; back then, 20,000 pounds was considered "heavy lift". Its development was taken over from the Advanced Research Projects Agency (ARPA) in 1958 by the newly formed civilian NASA. Its design proved sound and flexible. It was successful in initiating the development of liquid hydrogen-fueled rocket propulsion, launching the Pegasus satellites, and flight verification of the Apollo command and service module launch phase aerodynamics.
Ten Saturn I rockets were flown before it was replaced by the heavy lift derivative Saturn IB, which used a larger, higher total impulse second stage and an improved guidance and control system. It also led the way to development of the super-heavy lift Saturn V which carried the first men to landings on the Moon in the Apollo program.
President John F. Kennedy identified the Saturn I, and the SA-5 launch in particular, as being the point where US lift capability would surpass the Soviets, after being behind since Sputnik.Newsreel report of JFK with SA-1 (video)JFK Speech at Brooks AFB, 21Nov63 (video, on the last full day of his life)
History
Origins The Saturn project was started as one of a number of proposals to meet a new Department of Defense (DoD) requirement for a heavy-lift vehicle to orbit a new class of communications and "other" satellites. The requirements called for a vehicle capable of putting into orbit, or accelerating to trans-lunar injection. Existing U.S. launchers could place a maximum of about in orbit, but might be expanded to as much as with new high-energy upper stages. In any event, these upper stages would not be available until 1961 at the earliest, and would still not meet the DoD requirements for heavy loads.
Wernher von Braun's team at the U.S. Army Ballistic Missile Agency (ABMA) started studying the problem in April 1957. They calculated that a rocket with the required performance would require a lower-stage booster with a thrust of about 1.5 million pound-force (6.7 MN) thrust at takeoff. As it happened, the Air Force had recently started work on just such an engine, eventually emerging as the F-1. But the F-1 would not be available in the time frame that the DoD was demanding and would be limited to about 1 million lbf in the short term anyway. Another possibility was a Rocketdyne engine, then known as the E-1, which provided about , four of which would reach the required thrust levels. This approach became the favorite and was paired with a first stage built from a cluster of nine tanks placed atop a thrust plate where the engines and plumbing would be attached. The design envisaged eight rocket tanks similar to the Redstone stage strapped around a central larger tank derived from a Jupiter rocket. The design and diameter similarities would enable the use of the same tooling and facilities used to produce the older tanks, speeding up the design and production phases of the new stage. Contrary to what was reported to the press at the time (and propagated commonly ever since), the tanks were not simply Redstone and Jupiter tanks, but much longer versions built anew at the same diameter. However, the perception was that the first stage was a cluster of propellant tanks engineered from older rocket designs, leading critics to jokingly refer to it as "Cluster's Last Stand", a play on the nickname for the Battle of the Little Bighorn, "Custer's Last Stand".
Von Braun returned the design to DoD in December 1957 as A National Integrated Missile and Space Vehicle Development Program, outlining the new design, then known simply as "Super-Jupiter". Several variations were proposed, using a common clustered first stage, and upper stages based on either the Atlas or Titan I. ABMA favored the Titan as the Atlas production was extremely high-priority and there was little or no excess capacity to spare. They proposed using the existing Titan tooling at diameter, but lengthening it to produce a new -long stage. A Centaur would be used as a third stage, which was expected to be ready for operational use in 1963, right when the lower two stages would have completed their testing. The resulting three-stage design was much taller and skinnier than the Saturn design that was eventually built.
Advanced Research Projects Agency (ARPA) was formed in February 1958 as part of DoD and was in charge of the requirements. ARPA asked for only one change to the design; concerned that the E-1 was still in early development, they suggested looking at alternatives in order to ensure the rocket would enter production as soon as possible. ABMA quickly responded with a slightly modified design replacing the four E-1's with eight H-1 engines, a minor upgrade to the S-3D engine used on Thor and Jupiter missiles. They estimated that changing the engines would save about $60 million and as much as two years of research and development time.
von Braun had earlier referred to Redstone and Jupiter rockets being used as space launchers as the Juno I and Juno II, respectively, and had submitted proposals for multi-stage versions as the Juno III and IV. He changed the name of the new design to Juno V. The total development cost of $850 million ($5.6 billion in year-2007 dollars) between 1958 and 1963 also covered 30 research and development flights, some carrying crewed and uncrewed space payloads.
Work begins Satisfied with the outcome, ARPA Order Number 14-59, dated 15 August 1958, ordered the program into existence:Bilstein (1996), p. 27
Initiate a development program to provide a large space vehicle booster of approximately 1,500,000-lb. thrust based on a cluster of available rocket engines. The immediate goal of this program is to demonstrate a full-scale captive dynamic firing by the end of CY 1959.
This was followed on 11 September 1958 with another contract with Rocketdyne to start work on the H-1. On 23 September 1958, ARPA and the Army Ordnance Missile Command (AOMC) drew up an additional agreement enlarging the scope of the program, stating "In addition to the captive dynamic firing..., it is hereby agreed that this program should now be extended to provide for a propulsion flight test of this booster by approximately September 1960". Further, they wanted ABMA to produce three additional boosters, the last two of which would be "capable of placing limited payloads in orbit".
von Braun had high hopes for the design, feeling it would make an excellent test-bed for other propulsion systems, notably the F-1 if it matured. He outlined uses for the Juno V as a general carrier vehicle for research and development of "offensive and defensive space weapons". Specific uses were forecast for each of the military services, including navigation satellites for the Navy; reconnaissance, communications, and meteorological satellites for the Army and Air Force; support for Air Force crewed missions; and surface-to-surface logistics supply for the Army at distances up to 6400 kilometers. von Braun also proposed using the Juno V as the basis of a crewed lunar mission as part of Project Horizon. Juno could lift up to 20,000 pounds (9,000 kg) into low Earth orbit, and he proposed launching 15 of them to build a lunar spacecraft in Earth orbit.
Even by this point the name "Saturn", as "the one after Jupiter" was being used. One early ARPA report noted: "The SATURN is considered to be the first real space vehicle as the Douglas DC-3 was the first real airliner and durable work-horse in aeronautics". The name change became official in February 1959.
Transfer to NASA The formation of NASA on 29 July 1958 led to an effort to collect the existing heavy-launch rocket programs and select a single set of designs for future work. At the time, both the Air Force and US Army had teams developing such vehicles, the Army's Saturn and the Air Force's Space Launching System (SLS).Not to be confused with Space Launch System. The SLS used a set of common modular components with solid fuel boosters and hydrogen/oxygen upper stages to allow a wide variety of launch configurations and payload weights. Both groups had also developed plans for crewed lunar bases, ABMA's Horizon with its Earth Orbit Rendezvous method of building a large lunar rocket in Earth orbit, and the Air Force's Lunex Project which planned on launching a single huge lander using the largest of the SLS configurations. As if this were not enough, NASA's own engineers had started the design of their own Nova design series, planning to use it in the direct ascent profile similar to the Air Force's approach.
Von Braun was asked to chair a committee to study the existing efforts and write up recommendations. The committee presented their report on 18 July 1958, starting with a criticism of how the US program had been mishandled to date and pointing out that the Soviet program was definitely ahead. It went on to describe five "generations" of rockets, starting with the early Vanguard, through the Juno, ICBMs like Atlas and Titan, clustered designs like the Saturn, and finally, the ultimate development, a cluster using the F-1 with of thrust. The report went on to outline a crewed exploration program using these rockets as they become available; using existing ICBMs a small four-man space station could be operational 1961, the clusters would support a crewed lunar landing in 1965–1966 and a larger 50-man space station by 1967, while the largest of the rockets would support large Moon expeditions in 1972, set up a permanent Moon base in 1973–1974, and launch crewed interplanetary trips in 1977.
In December 1958, all of the teams gathered to present their designs. NASA selected von Braun's proposal on 6 January 1959, giving it a vital boost. At the end of January, NASA outlined their complete development program. This included the Vega and Centaur upper stages, as well as the Juno V and their own Nova boosters. Vega was later cancelled when information on the formerly secret Agena upper stage was released (then known as "Hustler"), and it had performance roughly comparable to NASA's design.
Near-cancellation Progress on the Saturn design seemed to go smoothly. In April 1959, the first H-1 engines started arriving at ABMA, and test firings started in May. Construction of the Complex 34 launch sites started at Cape Canaveral in June.
Then, quite unexpectedly, on 9 June 1959, Herbert York, Director of Department of Defense Research and Engineering, announced that he had decided to terminate the Saturn program. He later stated that he was concerned that the project was taking ARPA money from more pressing projects, and that as it seemed upgrades to existing ICBMs would provide the needed heavy-lift capability in the short term. As ABMA commander John B. Medaris put it:
By this time, my nose was beginning to sniff a strange odor of "fish". I put my bird dogs to work to try to find out what was going on and with whom we had to compete. We discovered that the Air Force had proposed a wholly different and entirely new vehicle as the booster for Dynasoar, using a cluster of Titan engines and upgrading their performance to get the necessary first-stage thrust for take-off. This creature was variously christened the Super Titan, or the Titan C. No work had been done on this vehicle other than a hasty engineering outline. Yet the claim was made that the vehicle in a two-stage or three-stage configuration could be flown more quickly than the Saturn, on which we had already been working hard for many months. Dates and estimates were attached to that proposal which at best ignored many factors of costs, and at worst were strictly propaganda.