A Canadian submarine spent decades as a political liability before it slipped three miles deep north of Kauai and fired a single torpedo into the bottom of an American warship.
19FortyFive and the UK Defence Journal report that HMCS Corner Brook sank the decommissioned Ticonderoga-class cruiser ex-USS Mobile Bay on July 12 during the Rim of the Pacific exercise. The cruiser, built around the Aegis combat system at a cost of roughly a billion dollars, launched Tomahawks in two wars before the U.S. Navy decommissioned it in 2023. Corner Brook is one of four Upholder-class boats Britain laid up in 1994 and sold to Canada.
Canada entered an eight-year lease-to-buy agreement in 1998 for the four diesel-electric submarines. The deal carried a nominal one-pound-sterling purchase price per boat, but a Defence Department audit later placed the final program cost at at least C$897 million after factoring in C$501 million for the main contract, C$160 million for initial support, and C$151 million for infrastructure and Canadian modifications, alongside other expenses outside the original scope. The boats measured 70.3 meters, displaced roughly 2,515 tonnes submerged, and gave Canada a submarine on each coast without requiring a native design program. That fleet suffered through a fatal 2004 fire aboard HMCS Chicoutimi and Corner Brook’s 2011 grounding before Corner Brook returned to operational service in 2025.
The live-fire sinking exercise allowed Corner Brook to execute a complete attack sequence against a large surface target, including detection, classification, tracking, and weapon release. The attack involved a Mark 48 heavyweight torpedo, part of an arsenal directed at the target alongside HIMARS rockets, Type 12 anti-ship missiles, Long Range Anti-Ship Missiles, Spike missiles, and Apache-launched Spike NLOS missiles.
Ottawa now wants 12 TKMS Type 212CD submarines.