BEIJING, Oct. 13 (Xinhuanet) -- China has been making technological upgrades on its space vessels and rockets by taking lessons from each launch, said Wang Yongzhi, chief designer of theChina Manned Space Program in an exclusive interview with Xinhua.

    While foreign scientists are surprised at China's fast progress and breakthrough in manned space technology, Chinese scientists have remained cool-headed about the reality.

    "We are very practical about the manned space program," Wang said. "Each launch has been helpful to make upgrades for the following one." From Shenzhou-1 to Shenzhou-5 spaceships, Chinese scientists have tried to improve the whole program and its seven systems.

    An excessive quantity of harmful gas was found in the first three Shenzhou vessels, and the problem was resolved at the Shenzhou-4 mission.

    Yang Liwei, the first astronaut aboard the Shenzhou-5, reported strong quivers for a while during the liftoff. His experience has resulted in a major technical improvement to make the craft more comfortable for the two Shenzhou-6 spacemen.

    Shenzhou-6 carries two astronauts and flies several days. During the space journey, the astronauts will move between the return capsule and orbiter. As a matter of fact, it is the first time that Chinese astronauts participate in laboratory work in space, Wang said. Enditem