The Space Shuttle is a true aerospace vehicle: it is launched like a rocket, orbits the Earth like a spacecraft and lands like a conventional airplane. The American Space Shuttle is the major component of the United States Space Transportation System (STS). Designs for the shuttle were conceived in the early 1970s as part of the United States' plan for the development of space transportation. The plan called for a balance between manned and unmanned operations. The shuttle supports the mannered operations of that plan.
The first shuttle flights began in April of 1981 and continued success was achieved during the first twenty four flights. A tragic disaster occurred on the twenty fifth flight when the shuttle Challenger exploded. The problem was traced to O-ring seals in the solid rocket boosters which were affected by unusually cold temperatures on the day of the launch. Despite warning from engineers, the launch was made with disastrous results. The shuttle was immediately grounded and for almost two years additional research and testing took place to correct the problems. It was not until the fall of 1988 that shuttle flights were resumed.
Many situations arise in space that require solving unforeseen problems. The unique qualities of the human mind are the best tools for solving these problems. Space shuttle crews have met challenges on several occasions. On one Space Shuttle mission, an astronaut was sent outside the orbiter to retrieve a satellite which had not achieved its proper orbit. Because the satellite was tumbling, it was quickly determined that this method would be too dangerous. After assessing the situation, the astronauts manoeuvred the Shuttle close to the satellite. They used its remote manipulator arm to capture the satellite and bring it back into the Shuttle cargo bay. After it was repaired, they redeployed the satellite so that it could boost itself into its proper orbit. This is but one of the many possible uses of the Shuttle.
The Space Shuttle can also be used to retrieve damaged satellites and return them to Earth for repair. It can take satellites into space and launch them into orbit. Its cargo bay can be used to take the European Space-lab into space so that scientific experiments can be carried out. It can also place large observatories in space, such as the Hubble Space Telescope. Plans for the 1990s call for using the Shuttle cargo bay to transport the basic elements of the structures for the Space Station which will be assembled in space.