BEIJING -- China's space tracking ship Yuanwang 3 has set sail from a Shanghai-based shipyard after completing maintenance in early July.

Cao Zhiyi, captain of Yuanwang 3, said the maintenance, focusing on the shafts and propellers, has improved the reliability of the ship's power system.

Commissioned on May 18, 1995, Yuanwang 3 represents the country's second-generation space tracking ship. It has undertaken nearly 100 maritime tracking and monitoring tasks of spacecraft, including the Shenzhou spaceships, Chang'e lunar probes and BeiDou satellites.