TAIPEI (Taiwan News) — Taiwan’s first domestically built submarine, the Narwhal, is undergoing underwater testing, with contractor CSBC Corp. on Sunday releasing video footage showing its maiden dive and a series of key system tests.

The footage documents testing conducted between Jan. 29 and Feb. 6, including the submarine’s first shallow-water dive, rudder and steering controls, antenna deployment, periscope operations, and decoy launches. CSBC said the video shows sea trials are progressing as planned, per CNA.

According to CSBC, the Narwhal conducted its first underwater test on Jan. 29 and has completed four underwater trials to date. The company said the video was released to maintain public support for Taiwan’s indigenous submarine development program.

CSBC said its shipbuilding team will continue system adjustments and safety checks before arranging subsequent tests based on evaluation results and the established testing schedule.

The footage shows the Narwhal departing port and heading to a designated test area for its first dive, with underwater and aerial views capturing steering system performance and exhaust valve operations during submergence. Additional scenes document the submarine’s return to port, highlighting initial sea trial results.

Media reports have said the submarine has attempted dives to depths of around 150 meters, with more advanced deep-diving tests exceeding 200 meters planned at a later stage.

CSBC said testing remains on track, with delivery of the submarine to the Navy now expected in June, later than the original target date of last November.