The Space Shuttle, post Apollo missions

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The Space Shuttle was partially reusable low orbit spacecraft operated by NASA. I was already mentioning Space Shuttle program in the previous article Shuttle-Mir Program. The Space Shuttle program was actually 4th manned US program, which was performing crew transportation from Earth to orbit between years 1981 and 2011, called Space Transportation System (STS). The Space Shuttle consisted of orbiter launched by two solid rocket boosters and external fuel tank, which was able to carry up to 8 astronauts.




Solid rocket boosters provided the biggest thrust during the first two minutes of the flight up to height 46 km. After they burned out, they were jettisoned and they parachuted into the Atlantic Ocean where they were recovered. After that they were checked and if possible they were used again. 

The meaning of solid rocket booster includes the entire rocket assembly, such as rocket motor, recovery parachutes, electronic instrumentation, separation rockets, safety destruct system and thrust vector motor. 

Solid rocket boosters separation


External fuel tank contained the liquid hydrogen fuel and liquid oxygen oxidizer. It supplied the fuel and oxidizer under pressure to the three Space Shuttle Engines.   

External tank

Rocket size comparison: Saturn V, Space Shuttle, Ares I, IV, V

The US Space Shuttle was the only manned winged spacecraft to achieve the orbit and to land. It was the only vehicle which has made multiple flights. Soviet shuttle Buran was very similar but it was used only once as unmanned spaceflight before it was cancelled.

Before Apollo 11 landed on the lunar surface, NASA began early studies of space shuttle. Newly created Space Task Group pointed post-Apollo missions with focus on manned space station, reusable vehicle used for transport, and manned mission to Mars. The last goal was left away and main objectives were set to the Earth low orbit. 

 The main goal was also to lower the cost. The reusable solid rocket boosters with extendable fuel tanks were developed. The first orbiter was originally called Constitution but because of Star Trek fans the name was changed to Enterprise (OV-101). Enterprise was rolled out on September 17, 1986.  

 The first experimental orbiter Enterprise was a high altitude glider, launched from the specially modified Boeing 747, for approach and landing test (ALT). The first test flight was on February 18, 1977. It was constructed without the real heat shield so it was not intended for spaceflight. 

Plans to reuse Skylab with Space Shuttle were stymied due to Space Shuttle development delays. Skylab's decay was not possible to stop.  

Another intended project in 1980s was Space Station Freedom, which was supposed to be an answer to Soviet Mir Space Station. The project evolved in to International Space Station (ISS). 


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