China's manned deep-sea submersible Jiaolong completes its 300th dive in the Western Pacific Ocean, Aug. 18, 2024. (Xinhua/Wang Yuhao)

China's manned deep-sea submersible Jiaolong has set a new record for dive frequency in its first hardware-testing mission after a major technical upgrade, according to the Ministry of Natural Resources.

During a mission from February 27 to March 25, Jiaolong achieved 14 successful dives in 10 days -- including an unprecedented four instances of completing two dives within a single day. The tests verified the reliability of newly upgraded domestic components, said the ministry.

These high-frequency, high-quality dives greatly enhanced Jiaolong's overall operational capability, laying a solid foundation for future intensive deployments, it said, adding that Jiaolong is expected to conduct over 80 dives in 2025.

Jiaolong, named after a mythical sea dragon, is capable of diving to depths exceeding 7,000 meters. It has explored waters in the Pacific Ocean, Indian Ocean and Atlantic Ocean.