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.
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