Kaohsiung: Taiwan’s indigenous defense submarine (IDS) prototype, christened Hai Kun or Narwhal in English, embarked on its first submerged tests after setting sail from Kaohsiung Harbor on Thursday. The event attracted dozens of military enthusiasts who gathered along the waterfront, waving the Republic of China (Taiwan) flag and chanting in support of the Hai Kun.

According to Focus Taiwan, the primary contractor for the IDS program, CSBC Corp., announced the commencement of the test in a press release issued the day before the submarine’s departure. Originally, the Hai Kun was scheduled to complete sea trials by November 2025, but the timeline was extended due to necessary final adjustments prior to the submergence tests.

Completion of these sea trials is a pivotal step for the IDS program. It would unlock NT$1 billion in funding for the construction of seven additional submarines, funding which was frozen by the Legislature last year due to previous delays. CSBC addressed frequent criticisms regarding the project’s cost and pace, comparing the four-year timeline of the Hai Kun’s development favorably against other international submarine construction timelines, such as the UK’s Upholder-class and South Korea’s KSS-II-class submarines.

CSBC highlighted that the Hai Kun’s cost of NT$37.9 billion, not including torpedoes and storage facilities, is relatively moderate when compared to other diesel-electric submarine programs worldwide. For example, South Korea’s Jang Bogo-class submarines and Germany’s Type 214 submarines cost NT$78.4 billion and NT$95.9 billion, respectively, at current exchange rates.