Kaohsiung: The Hai Kun (Narwhal), Taiwan’s first domestically built submarine, embarked on its fifth series of dive tests after leaving Port of Kaohsiung at approximately 8 a.m. on Tuesday.

According to Focus Taiwan, shipbuilder CSBC Corp., Taiwan has been facing fines due to missing a November 2025 deadline attributed to “testing delays.” However, the company expressed last month its intention to deliver the submarine to the Navy by June. Earlier video footage released by CSBC from the preceding four shallow-water dive trials, conducted between January 29 and February 6, showcased the submarine executing various functions. These included steering and control, opening vent valves, diving, elevating the periscope and antenna mast, altering depths, deploying decoys, and surfacing.

The Military News Agency further reported that assessments of the vessel’s maneuverability, reconnaissance capabilities, emergency procedures, and combat management systems have also been undertaken. These evaluations, alongside previous tests, were aimed at thoroughly verifying the Hai Kun’s performance and ensuring it aligns with the Navy’s operational standards and requirements.