The Jiaolong, a Chinese submersible on a two-month scientific exploration in the Pacific Ocean aboard its mother ship, the Xiangyanghong-09, underwent a full-body performance test and maintenance on Sunday.

Tests have shown that all the parts of the Jiaolong, the country's most advanced manned submersible, which achieved a dive depth record of more than 7,000 meters, is now in excellent condition, said Hu Zhen, deputy field commander for the research voyage.

This is the first comprehensive "body check" for the Jiaolong since the submersible successfully concluded an initial month-long experimental application diving mission in the South China Sea on July 10, which brought the first scientists below the sea to collect samples.

Aboard the Xiangyanghong-09, the Jiaolong departed from the southeast port city of Xiamen on Friday. In early August, it is scheduled to arrive at a northeast Pacific seabed polymetallic nodule ore zone. Explorations of this zone have been contracted to China.

The Jiaolong will undergo at least two more full-body checks before arriving at the target operation site on Aug. 6, a date that is foreseeable if weather is good, according to crew members.

In late August, the submersible is scheduled to arrive at a cobalt-rich ferromanganese crust ore in the western Pacific Ocean to conduct surveys, a plan approved by the International Seabed Authority on Friday. (Xinhua)