China developing manned submersible to reach deepest points

China is developing a manned submersible capable of reaching the deepest known points in the world's oceans in search of precious metals.
The 11,000-metre deep-sea submersible is planned to conduct its first ocean test in 2021, said Yan Kai, director of the state key laboratory of deep-sea manned submersible under the China Ship Scientific Research Centre.
Yan, a deputy to the National People's Congress, told state-run Xinhua news agency on the sidelines of the annual legislative session that the submersible is part of the Jiaolong family, whose manned device set China's record of reaching 7,062 metres deep in the Pacific Ocean's Mariana Trench in 2012.

Earlier this month, one of the submersibles, Jiaolong, operating in the northwesternIndianOcean,to search for deposits of precious metals descended to a new depth of 3,117 metres below sea level and collected a variety of samples.
Yan said the record-setting dive boosted the confidence of Chinese scientists in conducting deep-sea research exploration on their own and laid a solid foundation of developing even more sophisticated devices.
The known deepest part of the ocean is the Challenger Deep at a depth of around 11,000 metres in the Mariana Trench.

Submersibles capable of reaching that depth will offer new hopes of setting up deep-sea labs, where scientists can conduct biological, medical and genetic research and explore mineral, oil and gas resources.

But Yan said 11,000-metre submersible research still faces challenges in areas including pressure-resistent materials, design, energy and telecommunications.
Meanwhile, Yan's lab is in the final stages of developing a 4,500-meter submersible to be delivered to the Institute of Deep-sea Science and Engineering under the Chinese Academy of Sciences in the second half of this year.
The submersible, which was completely designed and made in China, is equipped with five observation windows and can stay underwater for 12 hours, creating favourable conditions for researchers to expand the scope of their observation, Yan said.
A series of submersibles to dive at a range of 1,000 to 2,000 metres are also being planned.

"Humans' understanding of the deep sea is shallower than that of the moon surface," he said.
"Conducting scientific research in the deep sea will boost our knowledge about the oceans and Earth", Yan said.