Expendable Space Rocket
The Saturn V rocket series proved crucial to success of the American space program of the late 1960s and early 1970s.
Authored By: Staff Writer | Last Edited:
The Cold War period (1947-1991), with its constant threat of nuclear war, spurred an arms race of epic proportions. Beyond this, the time was also ripe with technological advances particularly those related to space exploration. Despite the backdrop of Total War, the 1950s, 1960s, and 1970s were an exciting time for those interested in the secrets of space.
Before the Americans relied on the Space Shuttle and more modern advanced rockets of today, there was the Saturn V rocket program that powered the Apollo program and put the United States ahead of the Soviets in space. The rocket program was a massive undertaking involving a myriad of companies and hundreds of thousands of individuals to see it through. The Saturn V was used in no fewer than thirteen total launches for its time in history with twelve of these being successful. It allowed mankind to finally set foot on the surface of the moon.
The Saturn V rocket marked one of the greatest feats of engineering in, not only American history, but in all of humanity. The rocket remains (as of 2018) the largest, most powerful space vehicle to have ever been built and successfully, repeatedly used.
German World War 2 Rocketry Lights the Way
The American space program owes much of its origin to German rocket mastery in the Second World War. Towards the close of the war, Third Reich authorities approved the desperate measure of sending unmanned explosives-filled rockets to locations across lower England. This resulted in the V-2 rocket program which became the first use of a ballistic missile system in warfare. The V-2 was a much larger, more advanced rocket form following the smaller V-1 series. At any rate, these rockets terrorized population centers like London and V-2 launch sites were systematically targeted, in turn, by Allied attack planes.
Before the end of the war, German scientists saw the writing on the wall that the war's fortunes had turned against the Fatherland and were presented with the choice of joining the soon-to-be victorious Soviet Union in the East or the United States and its Allies in the West. Knowing their treatment at the hands of the Soviets would be worse, many opted to join the ranks of the West. Chief rocket scientist Wernher von Braun and a team of over 1,600 scientists secretly joined the United States rocket program soon after and, with this team of talented engineers also arrived a treasure trove of rocket-related data as well as some one-hundred intact V-2 rocket examples for further study.
The Soviet Challenge
The Soviets enjoyed progress in the field of rocketry all their own but Soviet leader Josef Stalin's political purges damaged much of what could have been. As with the Americans, the Soviets were able to claim German rocket scientists and rocket-related data towards the end of the war. In August of 1957 the Soviets successfully tested their R-7 "Semyorka" Intercontinental Ballistic Missile" (ICBM).
The Americans, and the West for that matter, were dealt a serious blow to their prestige when the Soviets launched their artificial satellite "Sputnik" in 1957 and this was followed shortly by "Sputnik 2" that same year. Further setbacks to American morale were had when the Soviets manage to send and recover the dog "Laika" into space - the first time a complex lifeform was sent into space and successfully retrieved. From this came the first man in space, Yuri Gagarin, who returned to Earth as, not only a Soviet hero, but a global hero as well in 1961. In 1963 followed the first woman in space, Valentina Tereshkova.
The Vanguard rocket program was quickly formulated as an American counter but this attempt to launch a satellite into Earth's orbit failed miserably in front of the cameras. In 1961, President John F. Kennedy laid down challenge that, within a decade, America would not only conquer Earth's atmosphere and enter its orbit, but also land a man on the moon and return him back to the planet intact.
The Basic challenge
There were many inherent challenges to the idea of getting a man to the moon and back. The process would involve fighting the natural gravity of the planet and getting a space-bound vehicle, weighing as much as a Navy warship, beyond the atmosphere of Earth. From there, the vehicle would have to orbit the planet and "slingshot" its way towards the moon. Once there, a lander would be deployed which would carry several crewmembers to the surface of the moon. For the return trip, the lander would launch its workspace environment towards the moon's own orbit. The orbiting command module would then have to meet up with the lander's command center and slingshot the crew back to Earth's orbit - at which point the gravitational pull would take care of the rest of the journey home.
Werner Von Bruan championed the idea of a larger, more powerful rocket sitting a four-legged command module at its top to bring men to the moon and back. However, this concept was ultimately abandoned as being too complex and expensive to see through.
The Gemini Program
The Gemini program was used to test many of the systems, technologies, and procedures ultimately utilized in the Saturn V rocket project - known as the Apollo Program.
The Three Stage Approach
The Saturn V rocket comprised three different stages required to get the rocket out of, and beyond, Earth's atmosphere. All told, the system held an overall height of 363 feet with a diameter of 33 feet. Its weight reached a gaudy 6,540,000lb with a payload capacity of 310,000lb.
The First Stage
The primary, lower section was the largest and heaviest of the three stages. It was known by the designation of "S-IC" and measured 138 feet long with a diameter of 33 feet, weighing a hefty 5,040,000lb when fully fueled (287,000lb otherwise). At its base was affixed five of the powerful F1 propulsion thrusters build by the engineers of Rocketdyne which provided some 7,891,000lb of combined thrust designed to burn for 168 seconds. The thrusters were arranged in a two-by-one-by-two pattern under the rocket's body and were gimbaled so as to provide the lifting rocket with some control as it moved up its flight path towards Earth's atmosphere. The fuel mix involved RP-1 (Rocket Propellant-1) and LOX (Liquid Oxygen).
The Second Stage
North American Aviation was charged with design and development of the second stage - designated "S-II" - which added unique challenges all its own. Dimensions included a length of 81.5 feet with a diameter of 33 feet. Weight was 1,093,900lb when fully fueled (88,400lb otherwise). Originally, the section was to entail two separate fuel chambers but an initiative to save on weight and shorten the section resulted in the two chambers being fuses as one with only a thin insulating layer separating the two cryogenic liquids needed to fuel the thrusters of the second component. Propulsion power was from 5 x Rocketdyne J-2 thrusters (outputting 1,155,800lb of combined thrust) which held a burn time of 360 seconds using a combination fuel mix of LH2 (Liquid Hydrogen) and LOX. The computer powerhouse added its avionics/guidance systems to a ring fitted atop the second section and made up the heart of the rocket as a whole.
The Third Stage
The third stage - designated "S-IVB" - measured 61.6 feet long and had a diameter measuring 21,7 feet. Its weight reached 271,000lb gross (29,700lb when empty). This section was driven by a single Rocketdyne J-2 thruster unit outputting 225,000lb of power and would burn for 165 and 335 second in two burns for its part in the process. Again the fuel mix involved LH2 and LOX.
The Lunar Lander
The Lunar Lander (also known as "LEM" for short) was used as part of the rocket's design to serve as the lunar surface lander for two of the flight crew. Grumman Aircraft was charged with its development, and construction with design attribution given to Thomas J. Kelly. The lander portion held the two crewmen with the third residing in the command module left orbiting the moon. Dimensions included a height of 23 feet and a diameter of 31 feet. Designed for up to 75 hours of service, the lander weighed 36,200lb when fully deploy and sat on the surface of the moon by way of four legs with the upper portion serving as the crew's operating space. This upper section was launched at mission's end and retrieved by the orbiting module for the journey home. The lander suffered through early issues during its development but more than made up for the investment before the end of the Apollo program as a truly reliable instrument for space.
The Command Module
Lockheed designed and developed what would become the command module. This three-man workspace was attached to the final Saturn V rocket section that also included the lunar lander, a four-legged space vehicle to be used for landing on the surface of the moon. Atop this craft was the operating center of the lander and this was designed to separate from the lander's legs to rendezvous with the orbiting command module for the journey back to Earth.
At the very top of the Saturn V rocket was the crew escape mechanism which was designed to allow a relatively safe escape for the crew of three from the rocket should the rocket body come under any type of danger during launching. The escape process involved small rockets fired to guide the command module out of harm's way, the system landing in the water by way of parachutes deployed during the descent.
The Saturn V in Active Service
Three early forms of the Saturn V rocket were used to validate many areas of the program. The first vehicle in play became SA-500F and this vehicle operated as a facilities integration unit, testing out the precise measurements needed for the space vehicle to successfully perform under the expected conditions. The follow-up form became SA-500D which was used in testing the space vehicle's vibration due to the expected inherently violent forces at play. S-IC-T was an all-systems test vehicle whose first stage took the role in static firing of the main booster units.
The first-flight of the Saturn V rocket was had on November 9th, 1967 through "Apollo 4" (SA-501) - this also becoming the first named flight for the system. The space vehicle was unmanned for the flight which mimicked all active conditions for future launches ("All Up Test"). Apollo 6, vehicle SA-502, was similar in its project scope as it was unmanned. However, early shutdown of the J-2 engines forced the launch of April 4th, 1968 to be aborted in-flight. The first manned flight occurred on December 21st, 1968 under Apollo 8 (SA-503). This carried the full crew of three astronauts and served as the first translunar "injection" test of the Command/Service Module. Apollo 9 (SA-504) followed on March 3rd, 1969 and conducted manned low Earth orbit testing of the complete Apollo rocket (including the lunar module). A second translunar injection of the Lunar Module was successfully had on May 18th, 1969 with Apollo 10 (SA-505). Up to this point, all rocket launched from completed from launch pad 39A with this one switching to pad 39B.
The moment of truth for the Apollo program / Saturn V rocket project arrived on July 16th, 1969 when Apollo 11 (SA-506) successfully landed man on the moon at the Sea of Tranquility - making history for the United States and all of mankind.
Apollo 12 (SA-507) was launched on November 14th, 1969 and, despite the vehicle being struck by lightning no fewer than two times, the spacecraft was able to land its payload at the Ocean of Storms on the moon's surface.
Apollo 13 (SA-508) was launched on April 11th, 1970 and gathered much publicity for its time aloft as severe "pogo oscillations" (detailed below) encountered during lift-off caused a premature shutdown of the center engine of the second stage. This forced the other engines to carry the load and burn longer, thus throwing guidance off. Compounding issues with this launch eventually led to the lunar landing portion of the mission being cancelled and the crew being brought back safely to Earth (through much engineering work and prayers). This chapter of the Apollo Program was made into a Hollywood motion picture starring Tom Hanks (the aptly-titled "Apollo 13").
The pogo oscillation effect has been detailed as a reaction occurring in liquid-propellant based rocket engines resulting from combustion instability - that is an oscillation of pressure related to the injection chamber and the flow inherent in the injector plate making up a rocket engine, resulting in a consistent, repeating changing of pressures and flow - the movement akin to that of a child's pogo stick plaything. The result becomes unexpected changes to a rocket engine's flow which can have very undesirable effects (particularly on a rigid frame like a rocket body) for a craft attempting to overcome Earth's gravity and leave its atmosphere.
Apollo 14 (SA-509) was launched on January 31st, 1971 and became the third successful lunar landing mission, more or less erasing the failure of Apollo 13. Apollo 15 (SA-510) followed on July 26th, 1971 and recorded the program's forth lunar landing. This mission introduced the famous four-wheeled Lunar Roving Vehicle to the scene and carried the lunar orbital Scientific Instrument Module. The fifth successful lunar landing was covered by Apollo 16 (SA-511), launched April 16th, 1972, and targeted Descartes Highlands on the moon. Apollo 17 (SA-512) was launched on December 7th, 1972, and became the fifth and final lunar landing mission. It was also the only night time launch of the Saturn V rocket vehicle.
The final flight of the Saturn V space vehicle was recorded on May 14th, 1973 with the launch of Skylab 1 (SA-513) - unofficially "Apollo 18". This placed a laboratory (taking the place of the original third stage) into Earth's orbit.
SA-514 and SA-515 were originally planned Apollo rocket launches but never enacted. SA-514 was to make up the Apollo 19 mission but the vehicle's unused first stage ended up on display at the Johnson Space Center. The other two sections made their way to the Kennedy Space Center for display. SA-515 was to headline Apollo 20 and eventually was placed in reserve status for the Skylab 1 launch. Its first stage eventually made its home at the INFINITY Space Center in Mississippi while the second stage was preserved at the John Space Center. Its third stage was converted to serve as a replacement for the original Skylab module should it have failed. This piece ended its days at the National Air and Space Museum in Washington, D.C.
The Saturn V Legacy
The Saturn V system allowed the United States to wrestle the lead in space away from the Soviet Union and became the symbol of American space dominance for its time in the stars.
The project cost $6.417 billion dollars from beginning to end, marking it as one of the most expensive human endeavors ever attempted.
The Saturn V paved the way for the reusable space orbiter vehicle in the form of the Space Shuttle which enjoyed its own decades-long tenure as America's go-to space vehicle.