Encouraged by the successful implementation of the Apollo manned moon landing program, the United States also enthusiastically invested in developing a reusable space transportation system as a round-trip transportation system for the Skylab space station, and named it "SpaceShuttle", that is, "Space Shuttle". According to the definition of "space flight", Qian Xuesen, a famous Chinese scientist, translated it into "space shuttle".
The idea of the space shuttle is beautiful, but it is very difficult to implement. Americans have conceived many plans, but it is difficult to achieve the expected perfection. Take off from the ground, make full use of aerodynamic force like an airplane, so you must have wings and take off horizontally. So one of the earliest ideas, like heavy aircraft, was bigger than the B-52 giant bomber. Because it must have enough propellant to accelerate to the speed of the universe, huge fuel will support its body. It's too difficult to make such a monster fly into space orbit.
Later, a plan was put forward to split a huge plane in two so that the big one could carry the small one. A big plane flies in the earth's atmosphere. It can only carry fuel and burn with oxygen in the air, so it can be greatly slimmed down. After reaching a certain speed, the small plane starts the rocket engine into orbit, so it is called an "orbiter". However, the carrying capacity of this kind of orbiter is limited.
197 1 year, Rockwell Company of the United States introduced a new two-stage scheme to lengthen and enlarge the orbiter. This scheme is technically difficult to implement and the cost is high. 1972, American Grumman Company put forward a new scheme, giving up the idea of all reuse, putting the largest propellant used during take-off in an external fuel tank and throwing it away after use. At the same time, two more solid rockets are set up to help take off and separate after completing the mission. Of course, in this case, it must be launched vertically. The cost of this scheme is low, and after improvement, it is the current space shuttle.
Although it is partially reused, it is still difficult to develop technically. The space shuttle didn't appear until Skylab 1979 crashed in July. 1981April 12, the space shuttle successfully conducted its first orbital test flight.