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Saturn INT-21
Encyclopedia
The Saturn INT-21 was a study for an American
orbit
al launch vehicle
of the 1970s. It was derived from the Saturn V
rocket
used for the Apollo program
, using its first
and second
stages, but lacking the third
stage. The guidance unit
would be moved from the top of the third stage to the top of the second stage. The INT-21 was never flown in this form.
A related variant was launched once, from the Kennedy Space Center
, Florida
carrying the Skylab
space station
into orbit, at 17:30 GMT, on May 14, 1973. As Skylab was built from an S-IVB stage, there was no need to move the guidance unit. This version was intended to be used for other flights in the Apollo Applications Program
, and would have also been used to launch other American space stations, including Skylab B
.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
orbit
Orbit
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...
al launch vehicle
Launch vehicle
In spaceflight, a launch vehicle or carrier rocket is a rocket used to carry a payload from the Earth's surface into outer space. A launch system includes the launch vehicle, the launch pad and other infrastructure....
of the 1970s. It was derived from the Saturn V
Saturn V
The Saturn V was an American human-rated expendable rocket used by NASA's Apollo and Skylab programs from 1967 until 1973. A multistage liquid-fueled launch vehicle, NASA launched 13 Saturn Vs from the Kennedy Space Center, Florida with no loss of crew or payload...
rocket
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...
used for the Apollo program
Project Apollo
The Apollo program was the spaceflight effort carried out by the United States' National Aeronautics and Space Administration , that landed the first humans on Earth's Moon. Conceived during the Presidency of Dwight D. Eisenhower, Apollo began in earnest after President John F...
, using its first
S-IC
The S-IC was the first stage of the Saturn V rocket. The S-IC first stage was built by The Boeing Company. Like the first stages of most rockets, most of its mass of over two thousand metric tonnes at launch was propellant, in this case RP-1 rocket fuel and liquid oxygen oxidizer...
and second
S-II
The S-II was the second stage of the Saturn V rocket. It was built by North American Aviation. Using liquid hydrogen and liquid oxygen it had five J-2 engines in a cross pattern...
stages, but lacking the third
S-IVB
The S-IVB was built by the Douglas Aircraft Company and served as the third stage on the Saturn V and second stage on the Saturn IB. It had one J-2 engine...
stage. The guidance unit
Saturn V Instrument Unit
The Saturn V Instrument Unit is a ring-shaped structure fitted to the top of the Saturn V rocket's third stage and the Saturn IB's second stage . It was immediately below the SLA panels that contained the Lunar Module. The Instrument Unit contains the guidance system for the Saturn V rocket...
would be moved from the top of the third stage to the top of the second stage. The INT-21 was never flown in this form.
A related variant was launched once, from the Kennedy Space Center
Kennedy Space Center
The John F. Kennedy Space Center is the NASA installation that has been the launch site for every United States human space flight since 1968. Although such flights are currently on hiatus, KSC continues to manage and operate unmanned rocket launch facilities for America's civilian space program...
, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
carrying the Skylab
Skylab
Skylab was a space station launched and operated by NASA, the space agency of the United States. Skylab orbited the Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems. It was launched unmanned by a modified Saturn V rocket, with a mass of...
space station
Space station
A space station is a spacecraft capable of supporting a crew which is designed to remain in space for an extended period of time, and to which other spacecraft can dock. A space station is distinguished from other spacecraft used for human spaceflight by its lack of major propulsion or landing...
into orbit, at 17:30 GMT, on May 14, 1973. As Skylab was built from an S-IVB stage, there was no need to move the guidance unit. This version was intended to be used for other flights in the Apollo Applications Program
Apollo Applications program
The Apollo Applications Program was established by NASA headquarters in 1968 to develop science-based manned space missions using surplus material from the Apollo program...
, and would have also been used to launch other American space stations, including Skylab B
Skylab B
Skylab B was a proposed second US space station similar to Skylab that was planned to be launched by NASA for different purposes, mostly involving the Apollo-Soyuz Test Project, but was canceled due to lack of funding. Two Skylab modules were built in 1970 by McDonnell Douglas for the Skylab...
.
See also
![](http://image.absoluteastronomy.com/images/encyclopediaimages/s/sk/skylab_launch_on_saturn_v.jpg)
- Comparison of super heavy lift launch systems
- Project ApolloProject ApolloThe Apollo program was the spaceflight effort carried out by the United States' National Aeronautics and Space Administration , that landed the first humans on Earth's Moon. Conceived during the Presidency of Dwight D. Eisenhower, Apollo began in earnest after President John F...
- Saturn I
- Saturn IBSaturn IBThe Saturn IB was an American launch vehicle commissioned by the National Aeronautics and Space Administration for use in the Apollo program...
- Saturn VSaturn VThe Saturn V was an American human-rated expendable rocket used by NASA's Apollo and Skylab programs from 1967 until 1973. A multistage liquid-fueled launch vehicle, NASA launched 13 Saturn Vs from the Kennedy Space Center, Florida with no loss of crew or payload...
- SkylabSkylabSkylab was a space station launched and operated by NASA, the space agency of the United States. Skylab orbited the Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems. It was launched unmanned by a modified Saturn V rocket, with a mass of...
- Apollo Applications ProgramApollo Applications programThe Apollo Applications Program was established by NASA headquarters in 1968 to develop science-based manned space missions using surplus material from the Apollo program...
- S-ICS-ICThe S-IC was the first stage of the Saturn V rocket. The S-IC first stage was built by The Boeing Company. Like the first stages of most rockets, most of its mass of over two thousand metric tonnes at launch was propellant, in this case RP-1 rocket fuel and liquid oxygen oxidizer...
- S-IIS-IIThe S-II was the second stage of the Saturn V rocket. It was built by North American Aviation. Using liquid hydrogen and liquid oxygen it had five J-2 engines in a cross pattern...
- SA-1SA-1 (Apollo)SA-1 was the first Saturn I space launch vehicle, the first in the Saturn family, and was part of the American Apollo program. The rocket was launched on October 27, 1961 from Cape Canaveral, Florida.-Objectives:...