![Saturn family of rockets](https://upload.wikimedia.org/wikipedia/commons/4/4c/Saturn_family_of_rockets.jpg)
The Saturn family of American
rocket
A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely fr ...
s was developed by a team of mostly
German rocket engineers and scientists led by
Wernher von Braun
Wernher Magnus Maximilian Freiherr von Braun ( , ; 23 March 191216 June 1977) was a German and American aerospace engineer and space architect. He was a member of the Nazi Party and Allgemeine SS, as well as the leading figure in the develop ...
to launch heavy payloads to
Earth orbit
Earth orbits the Sun at an average distance of 149.60 million km (92.96 million mi) in a counterclockwise direction as viewed from above the Northern Hemisphere. One complete orbit takes days (1 sidereal year), during which time Earth ...
and beyond. The Saturn family used
liquid hydrogen
Liquid hydrogen (LH2 or LH2) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.
To exist as a liquid, H2 must be cooled below its critical point of 33 K. However, for it to be in a fully li ...
as fuel in the
upper stage
A multistage rocket or step rocket is a launch vehicle that uses two or more rocket ''stages'', each of which contains its own engines and propellant. A ''tandem'' or ''serial'' stage is mounted on top of another stage; a ''parallel'' stage is ...
s. Originally proposed as a
military satellite
A military satellite is an artificial satellite used for a military purpose. The most common missions are intelligence gathering, navigation and military communications.
The first military satellites were photographic reconnaissance missions. So ...
launcher, they were adopted as the
launch vehicle
A launch vehicle or carrier rocket is a rocket designed to carry a payload (spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pad, launch pads, supported by a missile launch contro ...
s for the
Apollo Moon program. Three versions were built and flown: the
medium-lift Saturn I
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". The rocket's first stag ...
, the
heavy-lift
An airlift is the organized delivery of supplies or personnel primarily via military transport aircraft.
Airlifting consists of two distinct types: strategic and tactical. Typically, strategic airlifting involves moving material long distance ...
Saturn IB
The Saturn IB (also known as the uprated Saturn I) was an American launch vehicle commissioned by the NASA, National Aeronautics and Space Administration (NASA) for the Apollo program. It uprated the Saturn I by replacing the S-IV second stage (, ...
, and the
super heavy-lift Saturn V
Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with multistage rocket, three stages, and powered with liquid-propellant r ...
.
The Saturn name was proposed by von Braun in October 1958 as a logical successor to the
Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...
series as well as
the Roman god's powerful position.
In 1963, President
John F. Kennedy
John Fitzgerald Kennedy (May 29, 1917 – November 22, 1963), often referred to by his initials JFK and the nickname Jack, was an American politician who served as the 35th president of the United States from 1961 until his assassination i ...
identified the
Saturn I SA-5
Saturn-Apollo 5 (SA-5) was the first launch of the Block II Saturn I rocket and was part of the Apollo program. In 1963, President Kennedy identified this launch as the one which would place US lift capability ahead of the Soviets, after being b ...
launch as being the point where US lift capability would surpass the
Soviets
Soviet people ( rus, сове́тский наро́д, r=sovyétsky naród), or citizens of the USSR ( rus, гра́ждане СССР, grázhdanye SSSR), was an umbrella demonym for the population of the Soviet Union.
Nationality policy in th ...
, after having been behind since
Sputnik
Sputnik 1 (; see § Etymology) was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space program. It sent a radio signal back to Earth for t ...
. He last mentioned this in a speech given at
Brooks AFB
Brooks Air Force Base was a United States Air Force facility located in San Antonio, Texas, southeast of Downtown San Antonio.
In 2002, Brooks Air Force Base was renamed Brooks City-Base when the property was conveyed to the Brooks Developmen ...
in San Antonio on the day before he was assassinated.
To date, the Saturn V is the only launch vehicle to transport human beings beyond
low Earth orbit
A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...
. A
total of 24 humans were flown to the Moon in the four years spanning December 1968 through December 1972. No Saturn rocket failed catastrophically in flight.
Summary of variants
All the Saturn family rockets are listed here by date of introduction.
History
Early development
![SA-1 launch](https://upload.wikimedia.org/wikipedia/commons/b/bf/SA-1_launch.jpg)
In the early 1950s, the
US Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...
and
US Army
The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...
actively developed long-range missiles with the help of German rocket engineers who were involved in developing the successful
V-2
The V-2 (german: Vergeltungswaffe 2, lit=Retaliation Weapon 2), with the technical name ''Aggregat 4'' (A-4), was the world’s first long-range guided ballistic missile. The missile, powered by a liquid-propellant rocket engine, was developed ...
during the Second World War. These missiles included the Navy's
Viking
Vikings ; non, víkingr is the modern name given to seafaring people originally from Scandinavia (present-day Denmark, Norway and Sweden),
who from the late 8th to the late 11th centuries raided, pirated, traded and se ...
, and the Army's
Corporal
Corporal is a military rank in use in some form by many militaries and by some police forces or other uniformed organizations. The word is derived from the medieval Italian phrase ("head of a body"). The rank is usually the lowest ranking non ...
,
Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...
and
Redstone. Meanwhile, the
US Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...
developed its
Atlas
An atlas is a collection of maps; it is typically a bundle of maps of Earth or of a region of Earth.
Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats. In addition to presenting geographic ...
and
Titan
Titan most often refers to:
* Titan (moon), the largest moon of Saturn
* Titans, a race of deities in Greek mythology
Titan or Titans may also refer to:
Arts and entertainment
Fictional entities
Fictional locations
* Titan in fiction, fictiona ...
missiles, relying more on American engineers.
Infighting among the various branches was constant, with the
United States Department of Defense
The United States Department of Defense (DoD, USDOD or DOD) is an executive branch department of the federal government charged with coordinating and supervising all agencies and functions of the government directly related to national secu ...
(DoD) deciding which projects to fund for development. On November 26, 1956, Defense Secretary
Charles E. Wilson issued a memorandum stripping the Army of offensive missiles with a range of or greater, and turning their Jupiter missiles over to the Air Force.
[Cadbury (2006), p. 154] From that point on, the Air Force would be the primary missile developer, especially for dual-use missiles that could also be used as space
launch vehicle
A launch vehicle or carrier rocket is a rocket designed to carry a payload (spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pad, launch pads, supported by a missile launch contro ...
s.
In late 1956, the Department of Defense released a requirement for a heavy-lift vehicle to orbit a new class of communications and "other" satellites (the
spy satellite
A reconnaissance satellite or intelligence satellite (commonly, although unofficially, referred to as a spy satellite) is an Earth observation satellite or communications satellite deployed for military or intelligence applications.
The ...
program was
top secret
Classified information is material that a government body deems to be sensitive information that must be protected. Access is restricted by law or regulation to particular groups of people with the necessary security clearance and need to know, ...
). The requirements, drawn up by the then-unofficial
Advanced Research Projects Agency
The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military.
Originally known as the Adv ...
(ARPA), called for a vehicle capable of putting 9,000 to 18,000 kilograms into orbit, or accelerating 2,700 to 5,400 kg to escape velocity.
[Bilstein (1996)]
p. 25
Since the Wilson memorandum covered only weapons, not space vehicles, the
Army Ballistic Missile Agency
The Army Ballistic Missile Agency (ABMA) was formed to develop the United States Army, U.S. Army's first large ballistic missile. The agency was established at Redstone Arsenal on 1 February 1956, and commanded by Major General John Bruce Meda ...
(ABMA) saw this as a way to continue the development of their own large-rocket projects. In April 1957, von Braun directed
Heinz-Hermann Koelle Heinz-Hermann Koelle (22 July 1925, in Danzig, Free City of Danzig – 20 February 2011, in Berlin, Germany) was an aeronautical engineer who made the preliminary designs on the rocket that would emerge as the Saturn I. Closely associated wi ...
, chief of the Future Projects design branch, to study dedicated launch vehicle designs that could be built as quickly as possible. Koelle evaluated a variety of designs for missile-derived launchers that could place a maximum of about 1,400 kg in orbit, but might be expanded to as much as 4,500 kg with new high-energy upper stages. In any event, these upper stages would not be available until 1961 or 1962 at the earliest, and the launchers would still not meet the DoD requirements for heavy loads.
[H. H. Koelle et al., "Juno V Space Vehicle Development Program, Phase I: Booster Feasibility Demonstration", ABMA, Redstone Arsenal, Report DSP-TM-10-58, October 13, 1958]
In order to fill the projected need for loads of 10,000 kg or greater, the ABMA team calculated that a booster (first stage) with a thrust of about thrust would be needed, far greater than any existing or planned missile.
[Neufeld (2007), p. 331] For this role they proposed using a number of existing missiles clustered together to produce a single larger booster; using existing designs they looked at combining tankage from one Jupiter as a central core, with eight Redstone diameter tanks attached to it.
This relatively cheap configuration allowed existing fabrication and design facilities to be used to produce this "quick and dirty" design.
Two approaches to building the Super-Jupiter were considered; the first used multiple engines to reach the mark, the second used a single much larger engine. Both approaches had their own advantages and disadvantages. Building a smaller engine for clustered use would be a relatively low-risk path from existing systems, but required duplication of systems and made the possibility of a stage failure much higher (adding engines generally reduces reliability, as per
Lusser's law). A single larger engine would be more reliable, and would offer higher performance because it eliminated duplication of "dead weight" like propellant plumbing and hydraulics for steering the engines. On the downside, an engine of this size had never been built before and development would be expensive and risky. The Air Force had recently expressed an interest in such an engine, which would develop into the famed
F-1, but at the time they were aiming for and the engines would not be ready until the mid-1960s. The engine-cluster appeared to be the only way to meet the requirements on time and budget.
[
Super-Jupiter was the first-stage booster only; to place payloads in orbit, additional upper stages would be needed. ABMA proposed using either the Titan or Atlas as a second stage,][Neufeld (2007), p. 341.] optionally with the new Centaur
A centaur ( ; grc, κένταυρος, kéntauros; ), or occasionally hippocentaur, is a creature from Greek mythology with the upper body of a human and the lower body and legs of a horse.
Centaurs are thought of in many Greek myths as being ...
upper-stage.[Dawson & Bowles (2004), p. 24.] The Centaur had been proposed by General Dynamics
General Dynamics Corporation (GD) is an American publicly traded, aerospace and defense corporation headquartered in Reston, Virginia. As of 2020, it was the fifth-largest defense contractor in the world by arms sales, and 5th largest in the Uni ...
(Astronautics Corp.) as an upper stage for the Atlas (also their design) in order to quickly produce a launcher capable of placing loads up to into low Earth orbit.[Dawson & Bowles (2004), pp. 22–24.] The Centaur was based on the same "balloon tank" concept as the Atlas, and built on the same jigs at the same diameter. As the Titan was deliberately built at the same size as well, this meant the Centaur could be used with either missile. Given that the Atlas was the higher priority of the two ICBM projects and its production was fully accounted for, ABMA focused on "backup" design, Titan, although they proposed extending it in length in order to carry additional fuel.
In December 1957, ABMA delivered ''Proposal: A National Integrated Missile and Space Vehicle Development Program'' to the DoD, detailing their clustered approach. They proposed a booster consisting of a Jupiter missile airframe surrounded by eight Redstones acting as tankage, a thrust plate at the bottom, and four Rocketdyne E-1 Rocketdyne's E-1 was a liquid propellant rocket engine originally built as a backup design for the Titan I missile. While it was being developed, Heinz-Hermann Koelle at the Army Ballistic Missile Agency (ABMA) selected it as the primary engine for ...
engines, each having of thrust. The ABMA team also left the design open to future expansion with a single engine, which would require relatively minor changes to the design. The upper stage was the lengthened Titan, with the Centaur on top. The result was a very tall and skinny rocket, quite different from the Saturn that eventually emerged.
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 km. Development and testing of the lower stage stack were projected to be completed by 1963, about the same time that the Centaur should become available for testing in combination. The total development cost of $850 million during the years 1958-1963 covered 30 research and development flights.
Sputnik stuns the world
While the Super-Jupiter program was being drawn up, preparations were underway for the first satellite launch as the US contribution to the International Geophysical Year
The International Geophysical Year (IGY; french: Année géophysique internationale) was an international scientific project that lasted from 1 July 1957 to 31 December 1958. It marked the end of a long period during the Cold War when scientific ...
in 1957. For complex political reasons, the program had been given to the US Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...
under Project Vanguard
Project Vanguard was a program managed by the United States Navy Naval Research Laboratory (NRL), which intended to launch the first artificial satellite into low Earth orbit using a Vanguard rocket. as the launch vehicle from Cape Canaveral ...
. The Vanguard launcher consisted of a Viking
Vikings ; non, víkingr is the modern name given to seafaring people originally from Scandinavia (present-day Denmark, Norway and Sweden),
who from the late 8th to the late 11th centuries raided, pirated, traded and se ...
lower stage combined with new uppers adapted from sounding rocket
A sounding rocket or rocketsonde, sometimes called a research rocket or a suborbital rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The rockets are used to ...
s. ABMA provided valuable support on Viking and Vanguard, both with their first-hand knowledge of the V-2, as well as developing its guidance system. The first three Vanguard suborbital test flights had gone off without a hitch, starting in December 1956, and a launch was planned for late 1957.
On October 4, 1957, the Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...
surprised the world with the launch of Sputnik I
Sputnik 1 (; see § Etymology) was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space program. It sent a radio signal back to Earth for t ...
. Although there had been some indications that the Soviets were working towards this goal, few in the U.S. military and scientific establishment considered these efforts seriously.
When asked in November 1954 about the possibility of the Soviets launching a satellite, Defense Secretary Wilson replied: "I wouldn't care if they did."["Project Vanguard, Why it failed to live up to its name"]
''Time'' magazine, October 21, 1957 The public did not see it the same way, however, and the event was a major public relations disaster for the US. Vanguard was planned to launch shortly after Sputnik, but a series of delays pushed this into December, when the rocket exploded in spectacular fashion. The press was harsh, referring to the project as "Kaputnik" or "Project Rearguard".[ As ''Time'' magazine noted at the time:
:But in the midst of the cold war, Vanguard's cool scientific goal proved to be disastrously modest: the Russians got there first. The post-Sputnik White House explanation that the U.S. was not in a satellite "race" with Russia was not just an after-the-fact alibi. Said Dr. Hagen ten months ago: "We are not attempting in any way to race with the Russians". But in the eyes of the world, the U.S. was in a satellite race whether it wanted to be or not, and because of the Administration's costly failure of imagination, Project Vanguard shuffled along when it should have been running. It was still shuffling when Sputnik's beeps told the world that Russia's satellite program, not the U.S.'s, was the vanguard.][
Von Braun responded to Sputnik I's launch by claiming he could have a satellite in orbit within 90 days of being given a go-ahead. His plan was to combine the existing ]Jupiter C
The Jupiter-C was an American research and development vehicle developed from the Jupiter-A. Jupiter-C was used for three unmanned sub-orbital spaceflights in 1956 and 1957 to test re-entry nosecones that were later to be deployed on the more a ...
rocket (confusingly, a Redstone adaptation, not a Jupiter) with the solid-fuel engines from the Vanguard, producing the Juno I
The Juno I was a four-stage American space launch vehicle, used to launch lightweight payloads into low Earth orbit. The launch vehicle was used between January 1958 to December 1959. The launch vehicle was a member of the Redstone launch veh ...
. There was no immediate response while everyone waited for Vanguard to launch, but the continued delays in Vanguard and the November launch of Sputnik II resulted in the go-ahead being given that month. Von Braun kept his promise with the successful launch of Explorer I
Explorer 1 was the first satellite launched by the United States in 1958 and was part of the U.S. participation in the International Geophysical Year (IGY). The mission followed the first two satellites the previous year; the Soviet Union's S ...
on 1 February 1958. Vanguard was finally successful on March 17, 1958.
ARPA selects Juno
Concerned that the Soviets continued to surprise the U.S. with technologies that seemed beyond their capabilities, the DoD studied the problem and concluded that it was primarily bureaucratic. As all of the branches of the military had their own research and development programs, there was considerable duplication and inter-service fighting for resources. Making matters worse, the DoD imposed its own Byzantine
The Byzantine Empire, also referred to as the Eastern Roman Empire or Byzantium, was the continuation of the Roman Empire primarily in its eastern provinces during Late Antiquity and the Middle Ages, when its capital city was Constantinopl ...
procurement and contracting rules, adding considerable overhead. To address these concerns, the DoD initiated the formation of a new research and development group focused on launch vehicles and given wide discretionary powers that cut across traditional Army/Navy/Air Force lines. The group was given the job of catching up to the Soviets in space technology as quickly as possible, using whatever technology it could, regardless of the origin. Formalized as Advanced Research Projects Agency
The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military.
Originally known as the Adv ...
(ARPA) on February 7, 1958, the group examined the DoD launcher requirements and compared the various approaches that were currently available.
At the same time that ABMA was drawing up the Super-Jupiter proposal, the Air Force was in the midst of working on their Titan C concept. The Air Force had gained valuable experience working with liquid hydrogen
Liquid hydrogen (LH2 or LH2) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.
To exist as a liquid, H2 must be cooled below its critical point of 33 K. However, for it to be in a fully li ...
on the Lockheed CL-400 Suntan
Suntan was the code-name of a prototype reconnaissance aircraft program, with the goal of creating a much faster and higher-altitude successor to the U-2, enabled by the use of liquid hydrogen (LH2) as aircraft fuel. The program was cancelled i ...
spy plane project and felt confident in their ability to use this volatile fuel for rockets. They had already accepted Krafft Ehricke's arguments that hydrogen was the only practical fuel for upper stages, and started the Centaur project based on the strength of these arguments. Titan C was a hydrogen-burning intermediate stage that would normally sit between the Titan lower and Centaur upper, or could be used without the Centaur for low-Earth orbit missiles like Dyna-Soar
The Boeing X-20 Dyna-Soar ("Dynamic Soarer") was a United States Air Force (USAF) program to develop a spaceplane that could be used for a variety of military missions, including aerial reconnaissance, bombing, space rescue, satellite maintena ...
. However, as hydrogen is much less dense than "traditional" fuels then in use, especially kerosene
Kerosene, paraffin, or lamp oil is a combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in aviation as well as households. Its name derives from el, κηρός (''keros'') meaning "wax", and was regi ...
, the upper stage would have to be fairly large in order to hold enough fuel. As the Atlas and Titan were both built at 120" diameters it would make sense to build Titan C at this diameter as well, but this would result in an unwieldy tall and skinny rocket with dubious strength and stability. Instead, Titan C proposed building the new stage at a larger 160" diameter, meaning it would be an entirely new rocket.
In comparison, the Super-Jupiter design was based on off-the-shelf components, with the exception of the E-1 engines. Although it too relied on the Centaur for high-altitude missions, the rocket was usable for low-Earth orbit without Centaur, which offered some flexibility in case Centaur ran into problems. ARPA agreed that the Juno proposal was more likely to meet the timeframes required, although they felt that there was no strong reason to use the E-1, and recommended a lower-risk approach here as well. ABMA responded with a new design, the Juno V (as a continuation of the Juno I
The Juno I was a four-stage American space launch vehicle, used to launch lightweight payloads into low Earth orbit. The launch vehicle was used between January 1958 to December 1959. The launch vehicle was a member of the Redstone launch veh ...
and Juno II
Juno II was an American space launch vehicle used during the late 1950s and early 1960s. It was derived from the Jupiter missile, which was used as the first stage.
Development
Solid rocket motors derived from the MGM-29 Sergeant were used ...
series of rockets, while Juno III and IV were unbuilt Atlas- and Titan-derived concepts), which replaced the four E-1 engines with eight H-1s, a much more modest upgrade of the existing S-3D already used on the Thor and Jupiter missiles, raising thrust from 150,000 to 188,000 lbf (670 to 840 kN). It was estimated that this approach would save as much as $60 million in development and cut as much as two years of R&D time.[Bilstein (1996)]
p. 27
Happy with the results of the redesign, on August 15, 1958, ARPA issued Order Number 14-59 that called on ABMA to:
: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.[Bilstein (1996)]
This was followed on September 11, 1958, with another contract with Rocketdyne to start work on the H-1. On September 23, 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."[Bilstein (1996)]
By this point, many in the ABMA group were already referring to the design as Saturn, as von Braun explained it as a reference to the planet after Jupiter.[Cadbury (2006), p. 188.] The name change became official in February 1959.[Bilstein (1996)]
NASA involvement
In addition to ARPA, various groups within the US government had been considering the formation of a civilian agency to handle space exploration. After the Sputnik launch, these efforts gained urgency and were quickly moved forward. NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
was formed on July 29, 1958, and immediately set about studying the problem of crewed space flight, and the launchers needed to work in this field. One goal, even in this early stage, was a crewed lunar mission. At the time, the NASA panels felt that the direct ascent
Direct ascent is a method of landing a spacecraft on the Moon or another planetary surface directly, without first assembling the vehicle in Earth orbit, or carrying a separate landing vehicle into orbit around the target body. It was proposed as ...
mission profile was the best approach; this placed a single very large spacecraft in orbit, which was capable of flying to the Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
, landing and returning to Earth. To launch such a large spacecraft, a new booster with much greater power would be needed; even the Saturn was not nearly large enough. NASA started examining a number of potential rocket designs under their Nova
A nova (plural novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", which is Latin for "new") that slowly fades over weeks or months. Causes of the dramati ...
program.
NASA was not alone in studying crewed lunar missions. Von Braun had always expressed an interest in this goal, and had been studying what would be required for a lunar mission for some time. ABMA's Project Horizon
Project Horizon was a 1959 study to determine the feasibility of constructing a scientific / military base on the Moon, at a time when the U.S. Department of the Army, Department of the Navy, and Department of the Air Force had total responsibil ...
proposed using fifteen Saturn launches to carry up spacecraft components and fuel that would be assembled in orbit to build a single very large lunar craft. This Earth orbit rendezvous mission profile required the least amount of booster capacity ''per launch'', and was thus able to be carried out using the existing rocket design. This would be the first step towards a small crewed base on the moon, which would require several additional Saturn launches every month to supply it.
The Air Force had also started their Lunex Project
The Lunex Project was a US Air Force 1958 plan for a crewed lunar landing prior to the Apollo Program. The final lunar expedition plan in 1961 was for a 21-person underground Air Force base on the Moon by 1968 at a total cost of $7.5 billion. Th ...
in 1958, also with a goal of building a crewed lunar outpost. Like NASA, Lunex favored the direct ascent mode, and therefore required much larger boosters. As part of the project, they designed an entirely new rocket series known as the Space Launcher System
The Space Launching System, or Space Launcher System, (SLS), was a 1960s-era design program of the US Air Force for a family of launch vehicles based around a set of common components. After a series of studies in the late 1950s, the Air Force ha ...
, or SLS (not to be confused with the Space Launch System
The Space Launch System (SLS) is an American super heavy-lift expendable launch vehicle developed by NASA. As of 2022, SLS has the highest payload capacity of any rocket in operational service, as well as the greatest liftoff thrust of any r ...
part of the Artemis program
The Artemis program is a robotic and human Moon exploration program led by the United States' National Aeronautics and Space Administration (NASA) along with three partner agencies: European Space Agency (ESA), Japan Aerospace Exploration ...
), which combined a number of solid-fuel boosters with either the Titan missile or a new custom booster stage to address a wide variety of launch weights. The smallest SLS vehicle consisted of a Titan and two strap-on solids, giving it performance similar to Titan C, allowing it to act as a launcher for Dyna-Soar. The largest used much larger solid-rockets and a much-enlarged booster for their direct ascent mission. Combinations in-between these extremes would be used for other satellite launching duties.
Silverstein Committee
A government commission, the "Saturn Vehicle Evaluation Committee" (better known as the Silverstein Committee The Saturn Vehicle Evaluation Committee, better known as the Silverstein Committee, was a US government commission assembled in 1959 to recommend specific directions that NASA could take with the Saturn rocket program. The committee was chaired by ...
), was assembled to recommend specific directions that NASA could take with the existing Army program. The committee recommended the development of new, hydrogen-burning upper stages for the Saturn, and outlined eight different configurations for heavy-lift boosters ranging from very low-risk solutions making heavy use of existing technology, to designs that relied on hardware that had not been developed yet, including the proposed new upper stage. The configurations were:
*Saturn A
**A-1
A1, A-1, A01 or A.1. may refer to:
Education
* A1, the Basic Language Certificate of the Common European Framework of Reference for Languages
* Language A1, the former name for "Language A: literature", one of the IB Group 1 subjects
* A1, a ...
– Saturn lower stage, Titan
Titan most often refers to:
* Titan (moon), the largest moon of Saturn
* Titans, a race of deities in Greek mythology
Titan or Titans may also refer to:
Arts and entertainment
Fictional entities
Fictional locations
* Titan in fiction, fictiona ...
second stage, and Centaur
A centaur ( ; grc, κένταυρος, kéntauros; ), or occasionally hippocentaur, is a creature from Greek mythology with the upper body of a human and the lower body and legs of a horse.
Centaurs are thought of in many Greek myths as being ...
third stage (von Braun's original concept).
**A-2
A2, A02, A002, A², A.II or A-2 may refer to:
Biology and medicine
* British NVC community A2 (Lemna minor community), a plant community
* A2, the second anal vein in the Comstock-Needham system of insect wing segment naming
Genes and proteins
* ...
– Saturn lower stage, proposed clustered Jupiter second stage, and Centaur third stage.
*Saturn B
** B-1 – Saturn lower stage, proposed clustered Titan second stage, proposed S-IV
The S-IV was the second stage of the Saturn I rocket used by NASA for early flights in the Apollo program.
The S-IV was manufactured by the Douglas Aircraft Company and later modified by them to the S-IVB, a similar but distinct stage used on th ...
third stage and Centaur fourth stage.
*Saturn C
** C-1 – Saturn lower stage, proposed S-IV
The S-IV was the second stage of the Saturn I rocket used by NASA for early flights in the Apollo program.
The S-IV was manufactured by the Douglas Aircraft Company and later modified by them to the S-IVB, a similar but distinct stage used on th ...
second stage (similar to the actual Saturn I
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". The rocket's first stag ...
).
** C-2 – Saturn lower stage, proposed S-II
The S-II (pronounced "S-two") was the second stage of the Saturn V rocket. It was built by North American Aviation. Using liquid hydrogen (LH2) and liquid oxygen (LOX) it had five J-2 engines in a quincunx pattern. The second stage accelerated ...
second stage, proposed S-IV third stage.
** C-3, C-4, and C-5 – all based on different variations of a new lower stage using F-1 engines, variations of proposed S-II second stages, and proposed S-IV third stages (with C-5 being similar to the actual Saturn V
Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with multistage rocket, three stages, and powered with liquid-propellant r ...
).
Contracts for the development of a new hydrogen-burning engine were given to Rocketdyne in 1960 and for the development of the Saturn IV stage to Douglas
Douglas may refer to:
People
* Douglas (given name)
* Douglas (surname)
Animals
*Douglas (parrot), macaw that starred as the parrot ''Rosalinda'' in Pippi Longstocking
*Douglas the camel, a camel in the Confederate Army in the American Civil W ...
the same year.
Launch history
Apollo program
The challenge that President John F. Kennedy
John Fitzgerald Kennedy (May 29, 1917 – November 22, 1963), often referred to by his initials JFK and the nickname Jack, was an American politician who served as the 35th president of the United States from 1961 until his assassination i ...
put to NASA in May 1961 to put an astronaut
An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a human spaceflight program to serve as a commander or crew member aboard a spacecraft. Although generally r ...
on the Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
by the end of the decade put a sudden new urgency on the Saturn program. That year saw a flurry of activity as different means of reaching the Moon were evaluated.
Both the Nova
A nova (plural novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", which is Latin for "new") that slowly fades over weeks or months. Causes of the dramati ...
and Saturn rockets, which shared a similar design and could share some parts, were evaluated for the mission. However, it was judged that the Saturn would be easier to get into production, since many of the components were designed to be air-transportable. Nova
A nova (plural novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", which is Latin for "new") that slowly fades over weeks or months. Causes of the dramati ...
would require new factories for all the major stages, and there were serious concerns that they could not be completed in time. Saturn required only one new factory, for the largest of the proposed lower stages, and was selected primarily for that reason.
The Saturn C-5 (later given the name Saturn V
Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with multistage rocket, three stages, and powered with liquid-propellant r ...
), the most powerful of the Silverstein Committee's configurations, was selected as the most suitable design. At the time the mission mode had not been selected, so they chose the most powerful booster design in order to ensure that there would be ample power.spaceline.org, SATURN I Fact Sheet, by Cliff Lethbridge
/ref> Selection of the lunar orbit rendezvous
Lunar orbit rendezvous (LOR) is a process for landing humans on the Moon and returning them to Earth. It was utilized for the Apollo program missions in the 1960s and 1970s. In a LOR mission, a main spacecraft and a smaller lunar lander travel to ...
method reduced the launch weight requirements below those of the Nova, into the C-5's range.
At this point, however, all three stages existed only on paper, and it was realized that it was very likely that the actual lunar spacecraft would be developed and ready for testing long before the booster. NASA, therefore, decided to also continue development of the C-1 (later Saturn I
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". The rocket's first stag ...
) as a test vehicle, since its lower stage was based on existing technology ( Redstone and Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...
tankage) and its upper stage was already in development. This would provide valuable testing for the S-IV as well as a launch platform for capsules and other components in low earth orbit.
The members of the Saturn family that were actually built were:
* Saturn I
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". The rocket's first stag ...
– ten rockets flew: five development flights, and five launches of boilerplate Apollo spacecraft and Pegasus micrometeoroid satellites.
* Saturn IB
The Saturn IB (also known as the uprated Saturn I) was an American launch vehicle commissioned by the NASA, National Aeronautics and Space Administration (NASA) for the Apollo program. It uprated the Saturn I by replacing the S-IV second stage (, ...
– nine launches; a refined version of the Saturn I with a more powerful first stage (designated the S-IB
The S-IB stage was the first stage of the Saturn IB launch vehicle, which was used for Earth orbital missions. It was composed of nine propellant containers, eight fins, a thrust structure assembly, eight H-1 rocket engines, and many other comp ...
) and using the Saturn V's S-IVB
The S-IVB (pronounced "S-four-B") was the third stage on the Saturn V and second stage on the Saturn IB launch vehicles. Built by the Douglas Aircraft Company, it had one J-2 (rocket engine), J-2 rocket engine. For lunar missions it was fired twi ...
as a second stage. These carried the first Apollo flight crew, plus three Skylab
Skylab was the first United States space station, launched by NASA, occupied for about 24 weeks between May 1973 and February 1974. It was operated by three separate three-astronaut crews: Skylab 2, Skylab 3, and Skylab 4. Major operations in ...
and one Apollo-Soyuz crews, into Earth orbit.
* Saturn V
Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with multistage rocket, three stages, and powered with liquid-propellant r ...
– 13 launches; the Moon rocket that sent Apollo astronauts to the Moon, and carried the Skylab
Skylab was the first United States space station, launched by NASA, occupied for about 24 weeks between May 1973 and February 1974. It was operated by three separate three-astronaut crews: Skylab 2, Skylab 3, and Skylab 4. Major operations in ...
space station into orbit.
File:AS-202 launch.jpg, A Saturn IB (AS-202
AS-202 (also referred to as SA-202) was the second uncrewed, suborbital test flight of a production Block I Apollo command and service module launched with the Saturn IB launch vehicle. It was launched on August 25, 1966, and was the first fli ...
) liftoff from LC-34
Launch Complex 34 (LC-34) is a deactivated launch site on Cape Canaveral Space Force Station, Florida. LC-34 and its companion LC-37 to the north were used by NASA from 1961 through 1968 to launch Saturn I and IB rockets as part of the Apollo p ...
File:S-IC engines and Von Braun.jpg, von Braun with the F-1 engines of the Saturn V
Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with multistage rocket, three stages, and powered with liquid-propellant r ...
first stage at the U.S. Space and Rocket Center
The U.S. Space & Rocket Center in Huntsville, Alabama is a museum operated by the government of Alabama, showcasing rockets, achievements, and artifacts of the U.S. space program. Sometimes billed as "Earth's largest space museum", astronaut Ow ...
File:Ap11-KSC-69PC-241HR.jpg, Rollout of Apollo 11's Saturn V to the launch pad
References
Citations
Bibliography
*
*
*
*
External links
NASA History Series Publications
(many of which are on-line)
{{DEFAULTSORT:Saturn (Rocket Family)
Rocket families
NASA space launch vehicles
1958 in science
1961 in spaceflight
Wernher von Braun