Taiwan's upgraded Hai Lung submarine will anchor a month of anti-submarine drills

Taiwan's navy will hold a month of joint sea and air anti-submarine drills in waters off the island's southwest from late October to late November, and its newly upgraded submarine Hai Lung will carry the exercise on its own, the Liberty Times reported on Wednesday, 14 October 2026, citing a government firing notice and military sources.

According to the notice, the navy's surface fleet and its 256th Submarine Squadron will run the drills in three waves between 28 October and 27 November. The portion led by the surface fleet is a joint sea-air anti-submarine exercise that will also involve air force P-3C maritime patrol aircraft and navy S-70C(M) anti-submarine helicopters.

The Hai Lung's sister boat, the Hai Hu, is in the shipyard for its own combat system upgrade, so the Hai Lung will be the only submarine taking part across the nearly month-long series. The report said the Hai Lung has finished its upgrade and has already fired an MK-48 practice torpedo. It now has a new combat management system that improves tracking and lets it engage several targets at once, and it can launch US-made MK-48 Mod 6 AT heavyweight torpedoes and submarine-launched Harpoon anti-ship missiles.

Military sources told the paper that the southwestern waters matter because they are deep, with complicated currents, and form a key passage for Chinese submarines trying to break through the first island chain into the Pacific. During the drills the Hai Lung is expected to play either the opposing force or the core of the underwater defence against the P-3Cs, helicopters and surface warships, with data links used to shorten the time from detecting a submarine to attacking it.

100 targets that sound like a Chinese submarine

In a second report the same day, military sources said the navy plans to buy 100 underwater self-propelled targets that can mimic the movement and propeller noise of a Chinese submarine, so that anti-submarine ships and aircrews can practise finding one. The paper used the US Mk 39 training target as an example: it is packed in a standard sonobuoy case, can be dropped from a patrol aircraft or thrown overboard by hand, gives off submarine-like noise, returns sonar echoes and follows programmed evasive manoeuvres.

For now the 100 targets will mainly be bought as mature US equipment to meet training needs quickly, the sources said. The National Chung-Shan Institute of Science and Technology has meanwhile signed co-production agreements and memoranda with US defence start-ups including Anduril to bring in underwater drone technology for local production. The report put China's submarine force at about 60 boats and said newer Type 039C Yuan-class boats with air-independent propulsion have been deployed to the Eastern Theatre Command.

Upgrade nears its final exam

The two Dutch-built boats have been in a NT$7.41 billion combat system upgrade since 2018, carried out by the institute with Lockheed Martin. The Hai Lung has returned to the fleet, while the Hai Hu entered the yard in May 2025 with completion expected by the end of 2026, Taiwan News reported in August. President Lai Ching-te boarded the upgraded Hai Lung during a visit to the 256th Submarine Squadron in March.

The navy has budgeted NT$208.6 million for 2027 as the last payment, which covers final combat system validation including the first live firing of MK-48 warshot torpedoes and submarine-launched Harpoons, China Times reported. Four practice torpedoes were due by the end of 2026, with 24 warshots to follow in 2027 and 2028.

That timetable makes the autumn drills a rehearsal with a single boat. Until the Hai Hu returns and the warshots arrive, Taiwan's anti-submarine practice rests on one upgraded submarine and, soon, on targets built to imitate the Chinese boats the navy expects to hunt.