Taiwan's Hai Kun Fires Its First Torpedo

On May 6, 2026, Taiwan’s first indigenously developed submarine, the SS-711 Hai Kun (海鯤), successfully conducted its maiden torpedo launch test — the most consequential weapons milestone in the program’s history to date.

State-owned shipbuilder CSBC Corp confirmed in a formal statement that the test verified the combat system’s full operational chain: detection and tracking, fire control, launch sequencing, and torpedo guidance. The Hai Kun — named after a mythological creature of unfathomable scale from the ancient text Zhuangzi — carries a Lockheed Martin combat system and is designed to deploy US-made Mark 48 heavyweight torpedoes. CSBC did not disclose the specific type of torpedo fired during the test.

The timing carried its own institutional pressure. The exercise torpedo system used in live-fire testing was leased from the United States under an arrangement running from May 2025 to May 2026. Fleet Command officials had previously told legislators the test would be completed within that window, and it was — narrowly. The successful firing removes one of the last major open questions ahead of navy delivery, currently scheduled for July 2026.

The program has not been without friction. CSBC began incurring navy fines in December 2025 after missing its original delivery deadline. The Hai Kun completed its first submerged trial only in January 2026, its 13th sea trial — and seventh submerged test — departing port on May 5, the day before the torpedo was fired. President William Lai had inspected the submarine personally in March, a gesture that underlined the program’s political weight.

The strategic logic behind the Hai Kun has never been subtle. Taiwan’s existing submarine inventory consists of two Dutch-built Hai Lung-class boats delivered in the 1980s and two World War II-era GUPPY conversions that remain nominally operational. Against a People’s Liberation Army Navy that has added more than 60 submarines over the past two decades, this inventory represents a capability deficit that is structural, not merely numerical. The indigenous program — targeting eight submarines total, with at least two in service by 2027 — is designed to address the asymmetric undersea dimension of any strait contingency.

Submarines are not deterrents in the declaratory sense. They deter by being present and undetectable, by forcing an adversary’s surface and anti-submarine assets into expensive, exhausting search patterns at the moment they are least able to spare the effort. A credible Taiwanese submarine force — even a small one — complicates any naval operation in or around the strait in ways that missile batteries and fighter aircraft cannot fully replicate. The Hai Kun’s torpedo test confirms, for the first time, that this platform can actually do what it was built to do.

Later variants of the Hai Kun class are expected to carry submarine-launched anti-ship missiles, extending the engagement envelope well beyond torpedo range. That capability remains prospective. What is no longer prospective is the basic question of whether Taiwan’s indigenous submarine can function as a weapons system. As of May 6, it can.

Delivery to the navy in July 2026 would mark the transition from a shipbuilder’s prototype to an operational military asset. The gap between those two states is real — tactical evaluation, integrated systems testing, and crew qualification lie ahead. But the trajectory is no longer in doubt. The Narwhal has teeth.

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