Published : 2025-06-24
On June 24, 2012, China's first independently designed and integrated manned submersible Jiaolong (蛟龍號) successfully broke through a depth of 7,000 metres during its fourth dive trial in the Mariana Trench, setting a new record for China's manned deep-diving.
At 4:30 a.m. that day, the team of Jiaolong's 7,000-metre sea trial held a ceremony for the pilots, and officially began the dive test at 5 a.m.
At 5:24 a.m., the Jiaolong submersible, carrying pilots Ye Cong, Liu Kaizhou, and Yang Bo, entered the water, and then began its dive five minutes later.
By 8:55 a.m., the Jiaolong had reached a depth of 7,000 metres, and subsequently sat on the seabed for the first time at a depth of 7,015 metres.
After completing the fourth dive trial of the 7,000-metre sea trial, Jiaolong safely returned to the test mother ship the same day, successfully setting a new record for China's manned deep-diving with a maximum depth of 7,020 metres.
Liu Feng (劉峰), the overall commander of the sea trial site, stated that the Jiaolong broke through the 7,000-metre depth after just four dive tests in the 7,000-metre sea trial, demonstrating the submersible's stable performance and the continuously improving skills of the sea trial personnel.
As an important tool for deep-sea exploration, manned submersibles are a crucial indicator of a country's marine exploration capabilities.
Before the Jiaolong, only the United States, Japan, France, and Russia owned deep-sea manned submersibles, yet their developed manned submersibles had a maximum working depth of no more than 6,500 metres, with frequent dives not exceeding 5,000 metres.
From its initial depth of 50 metres to 5,000 metres, and then to 7,000 metres in 2012, the Jiaolong has repeatedly broken records, proving China's capability to explore 99.8% of the global seabed and investigate oceanic life and the origins of life.