Working staff tie a cable to China's manned submersible Jiaolong in the west Pacific, June 13, 2017. China's manned submersible Jiaolong dived to 6,681 meters in the Yap Trench in the west Pacific Tuesday. The dive is the final one in China's 38th oceanic scientific expedition, marking the end of a four-year tentative application phase of the submersible. (Xinhua/Liu Shiping)

China's manned submersible Jiaolong leaves the water after its dive in the Yap Trench in the west Pacific, June 13, 2017. China's manned submersible Jiaolong dived to 6,681 meters in the Yap Trench in the west Pacific Tuesday. The dive is the final one in China's 38th oceanic scientific expedition, marking the end of a four-year tentative application phase of the submersible. (Xinhua/Liu Shiping)