Liu Guoning, a researcher of China's Manned Space Engineering Programme, talks about the extravehicular spacesuit at the Shenzhou VII Manned Space Flight Media Center on September 25, 2008. [Wang Wei/China.org.cn]

The safety of the astronaut is the first and most important priority in the task of designing an extravehicular spacesuit, said Liu Guoning, a researcher from China's Manned Space Engineering Programme.

Foreign astronauts have conducted over 200 extravehicular operations, amounting to several thousand hours. All indications are that there is little risk of a spacesuit being pierced by space debris. "Even if that happens, a series of standby systems are available to ensure the safety of the astronaut, including backup oxygen supply and protection systems."

An extravehicular spacesuit, provided with its own systems of environmental control and life support, is like a small independent spacecraft. All the power supply, temperature, and humidity control are self-sufficient. That is quite different from an intravehicular spacesuit, which is totally dependent on the spacecraft.

On the Shenzhou VII manned space flight mission, two astronauts will wear one first generation Feitian extravehicular spacesuit developed in China and one Orlan-M extravehicular spacesuit imported from Russia, to carry out the extravehicular activities.

According to Liu, the design of the extravehicular spacesuits from the two countries is based on the same philosophy: type of suit and hermetic control. Although there are differences in technology and reliability, the Chinese "Feitian" is also equipped with a number of new features.

Firstly, digital technology is extensively applied in the design of Feitian while Orlan-M, researched and designed in the 1970s-80s, only carries simulation technology. For Feitian, image and data transmission and information collection is conducted by digital signal.

Secondly, CDMA technology is applied in the Feitian's communication system while the Russian version depends on short-wave communication.

Thirdly, following the design of the intravehicular spacesuit, the elbow and knee joints of Feitian are softer than those of the Russian version.

In terms of the development of extravehicular spacesuits, America plans to combine the extra- and intravehicular spacesuits as a single unit. Efforts will be made to improve the suit's operational performance so that the lead time can be reduced before extravehicular activities.

(China.org.cn by Wang Wei, September 26, 2008)