August 14, 2026 – Defence Stories
Estimated read time – 1:47
By: LCdr Linda Coleman, RIMPAC Public Affairs Officer
Caption
The decommissioned Ticonderoga-class guided-missile cruiser USS Mobile Bay (CG 53), viewed through the periscope of Royal Canadian Navy Victoria-class long-range patrol submarine HMCS Corner Brook (SSK 878), during Exercise Rim of the Pacific 2026, July 12, 2026.
On July 12, His Majesty’s Canadian Submarine (HMCS) Corner Brook participated in a planned live-fire sinking exercise (SINKEX), contributing to the sinking of decommissioned USS Mobile Bay (CG 53) off the coast of Hawaii during Rim of the Pacific (RIMPAC) 2026. Mobile Bay was sunk in waters 15,000 feet deep, more than 50 nautical miles off the northern coast of the island of Kauai.
During the SINKEX, participating units from Australia, Canada, Japan, Spain, and the United States Navy, Air Force, and Army armed forces gained proficiency in tactics, targeting and, live-firing against a surface ship at sea. HMCS Corner Brook was the final unit to engage Mobile Bay, employing an MK 48 heavyweight torpedo that demonstrated the submarine’s precision strike capability in a complex multinational training environment and ultimately sent the ship to the bottom of the ocean.
Live-fire exercises deliver hands-on, realistic training that sharpens partner nations’ capabilities to coordinate, plan, and execute sophisticated maritime operations, including precision targeting and strike capabilities.
“Unique training opportunities such as these are invaluable to our submariners. Not only do they have the opportunity to demonstrate what they have learned by working together, both within the submarine and alongside partner nations to accomplish an extraordinary task, but they also get to showcase the expertise they have developed in their respective occupations and the significance of their contributions to Canada’s defence program,” said Capt(N) Landon Creasy, Task Group Commander 170.1 and Sea Combat Commander for RIMPAC.
Caption
USS Mobile Bay (CG 53), a decommissioned Ticonderoga-class guided missile cruiser, after Allied & Partnered vessels, including HMCS Corner Brook (SSK 878) fired on it during a Rim of the Pacific 2026 SINKEX on July 12, 2026.
During RIMPAC, HMCS Corner Brook operated alongside ships, aircraft, and submarines from participating nations in the world’s largest multinational maritime exercise. Prior to deployment, HMCS Corner Brook underwent an electronic warfare system upgrade, enhancing its ability to detect and identify nearby ships and signals.
30 nations, 30 surface ships, five submarines, 15 national land forces, more than 190 aircraft, and 30,000 personnel participated in RIMPAC this year in and around the Hawaiian Islands from June 24 to July 31.
In addition to HMCS Corner Brook, the Royal Canadian Navy deployed His Majesty’s Canadian Ships Regina, Ottawa, Motor Vessel Asterix, as well as Clearance and Port Inspection Divers. The Royal Canadian Air Force contributed a CP-140 Aurora Long-Range Patrol Aircraft Detachment, as well as two CH-148 Cyclone Maritime Helicopter Detachments embarked on HMCS Regina and Ottawa.
RIMPAC 2026 was the 30th exercise in the series that began in 1971. Canada is one of the three founding nations of RIMPAC and has participated in every iteration since then, demonstrating its ongoing commitment to strengthening partnerships and exercising joint-force capabilities in the Indo-Pacific region.
Associated links
DVIDS – News – U.S. and Partner Nations conduct SINKEX during RIMPAC 26
DVIDS – Video – U.S., partner nations conduct sinking exercises for Exercise Rim of the Pacific 2026