Victoria (Upholder)

The Upholder class, also known as Type 2400, was developed in the United Kingdom during the 1980s as a conventional submarine complement to the Royal Navy's nuclear boats. Only four were completed. After the UK concentrated submarine funding on nuclear-powered vessels, the class was declared surplus and later acquired by Canada, where the boats became the Victoria class.

As Type 2400 submarines, the boats were compact diesel-electric attack submarines built for stealth, torpedo employment, and conventional patrol work. Canadian conversion added national communications and fire-control work, while later sustainment addressed early mechanical and electrical issues. The design's value lay in quiet patrol capability, crew training, and undersea surveillance roles.

Royal Navy service was short because the post-Cold War defence review made the class expendable. In Canadian service, the submarines required lengthy reactivation and modernization, but the class eventually supported Royal Canadian Navy submarine training, surveillance, exercises, and deployments. HMCS Victoria's later milestones include Pacific operations and live heavyweight torpedo firing during RIMPAC.