Further to the hazards associated with the deep water littoral:
Hanwha Ocean, LIG, Magellan sign MoU to seek collaboration under the Canadian Patrol Submarine Project (CPSP).
canadiandefencereview.com
"LIG Defense & Aerospace (D&A), Magellan Aerospace Corporation (Magellan), and Hanwha Ocean have signed a Memorandum of Understanding to seek collaboration under the Canadian Patrol Submarine Project (CPSP), with a focus on strengthening Canada-based capabilities across underwater weapon systems and their lifecycle support."
"LIG D&A has played a central role in advancing South Korea’s indigenous undersea defence capabilities, beginning with the successful development and deployment of the country’s first domestically produced Heavy Weight Torpedo, Baeksang-eo. Building on this foundation, LIG has continued to innovate, developing next-generation systems such as the Tiger Shark Heavy Weight Torpedo, featuring fiber-optic guided control and advanced wake-homing capabilities, which has been fully integrated into the latest KSS-III submarines."
The Tiger Shark Heavy Weight Torpedo is a 1619 kg, 21" torpedo that covers 50 km at a speed of 55 knots. It carries a 260 kg warhead. It operates in depths of 2 to 600 m.
fr.wikipedia.org
Does it require a submarine to get it into position?
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The BAE Herne is an XLUUV/XLAUV based on a Canadian platform designed and built by Cellula Robotics
could a bae herne carry and launch 21" torpedos +6
Yes, the BAE Systems Herne Extra-Large Unmanned Underwater Vehicle (XLUUV) is designed to carry and launch weapons, including 21-inch torpedoes.
Here are the key details based on 2025–2026 developments:
Weapon Capability: Herne is designed to deploy torpedoes—such as the Sting Ray—for anti-submarine warfare, with specialized payload bays for this purpose.
Modular Payload Bay: The XLAUV features a flexible, modular design that allows for different configurations, including a 5,000-litre capacity module capable of holding weapons.
Launch Mechanism: Rather than traditional horizontal tubes, the Herne is designed to launch weapons vertically through the underside of its hull, allowing for covert attacks without having to surface.
Development Status: While initially focused on Intelligence, Surveillance, and Reconnaissance (ISR) and seabed warfare, integrating torpedoes is part of its planned evolution to a fully capable autonomous combat vessel.
The system is intended to provide a cost-effective, long-endurance autonomous platform that can operate in high-risk areas without risking a human crew.
"Reports suggest that more than 50 Herne units could be purchased for the price of a single Astute-class attack submarine."
If 50:1 and the Astute is 1.6 BUKP per boat then the Herne is expected to cost in the 40 to 50 MUSD range
The Tiger Sharks are in the 2-3 MUSD apiece range.
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And do you need more than a surf board with a radio?
The Wave Glider, powered by wave motion and solar power, costs in the region of $250,000 plus whatever sensors and weapons you wish to attach.
Two Tiger Sharks at 2-3 MUSD apiece and a floating station at under 1 MUSD and you have a deployable, and enduring, two kill package for something in the 5 to 10 MUSD range.
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Consider them as floating off route mines with a 50 km radius.
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Unit cost of the KS III is about 1000 MUSD apparently.
1 sub or
20 to 25 XLUUVs or
100 to 200 floating off route mines.