MELBOURNE, Australia — Taiwan has launched its first domestically-built submarine, marking a significant milestone in its efforts to replace an aging naval capability.

The diesel-electric attack submarine, christened the Hai Kun after a mythical sea creature in Chinese folklore, was launched at the shipyard of CSBC Shipyard in the southern city of Kaohsiung earlier on Thursday, Sept. 28.

The launch ceremony was attended by the self-ruling island’s president, Tsai Ing-wen, and comes seven years after Taiwan first decided to build its own submarines to replace the four elderly submarines currently operated by the country’s Republic of China Navy, or ROCN.

Photos of the launch ceremony published by the government and media present showed that the design has an X-rudder configuration for operations in shallow waters, with a pair of additional small horizontal fins.

However, Taiwan has not released the Hai Kun’s specifications, although local media has previously reported that it displaces approximately 2,500 tonnes and is 70 meters, or 230 feet, long.

It has also been reported that Taiwan has received significant foreign assistance in building the submarine, although 40% of components are local.

This overseas assistance reported includes a version of the AN/BYG-1 submarine combat management system, used in U.S. Navy nuclear submarines, being sold to Taiwan, along with digital sonar systems, integrated combat systems and auxiliary equipment systems, including periscopes.

The U.K. government has granted licenses to companies to export some $200 million worth of submarine technology and parts to Taiwan, and retired engineers from Japan’s Mitsubishi and Kawasaki Heavy Industries were believed to have provided technical support.

Reuters has also reported in November 2021 that that Taiwan had recruited engineers and retired submariners from the U.S., U.K., Australia, South Korea, India, Spain and Canada to work on the program and advise the ROCN on submarine construction and operations.

Taiwan is seeking to build eight submarines, with the Hai Kun expected to be commissioned into the ROCN in 2025 after sea trials following its launch.

Taiwan’s submarine fleet currently comprises two former U.S. Navy submarines built during World War II and two former Dutch Navy boats acquired in the late 1980s.

Mike Yeo is the Asia correspondent for Defense News.

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