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With the successful launching of "Shenzhou" I, II, III spacecraft, Jiuquan Satellite Launching Center, tucked away in the boundless deserts of Gansu Province, has earned a global fame. However, by far this modern manned "spaceport" is little known in regard to its designing and construction.

As early as 1988, the Beijing Special Engineering Design Research Institute was ordered to conduct conceptual studies on "launching and retrieving sites of manned spacecraft". In September 1992, top Chinese leaders decided to start the project.

As the designer of China's Jiuquan, Xichang and Taiyuan launching centers, the Institute immediately kicked off technological and economic feasibility studies on the launching system and located it in Jiuquan.

The missiles and satellites China launched in the past were all tested and transported horizontally and assembled vertically, but this cannot meet the demand for manned launching which requires the world's commonly used method of vertical assembly, test and transport.

The plant for vertical assembling and testing, being the heart of a launching site, can only be found in a few developed countries for it involves a large scale and requires the most sophisticated techniques. The United States, France and Russia use an all-steel framework, but it costs too much. The Institute, basing itself on the geographical features of the site and after conducting feasibility studies and analog testing, proposed a design of huge reinforced-concrete, framework-multi-cylinder space structure, which later turned out to be much superior to steel framework in fire-resisting, heat preserving and sound insulating and saved a sum over 40 million yuan (US$4.8 million).

The gate of China's assembling and testing plant can be called the "first gate in Asia" with its height 74 meters (243 feet), upper width eight meters (26 feet), lower width 14 meters (46 feet) and gross weight over 350 tons, which was selected from among dozens of designs considering structure, air tightness and other natures.

The grand space cleaning technique through air conditioning is decisive for rocket and spaceship testing. After comparing many designs, the researchers worked out a new design of full function, less investment and low operation cost.

A safe, precise propellant filling system is an important link of the launching system, whether filling is done safely and accurately or not concerns the success or failure of the launching mission, and a new, time-saving method was adopted for filling, using internet techniques.

The date if not far off when Chinese astronauts enter the space with the establishment and commission of the "spaceport", expert says.

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