HMS Trenchant S-91, SSN

HMS Trenchant is the fifth of seven boats ordered in the Trafalgar class, all built by Vickers Shipbuilding & Engineering Ltd (VSEL), in Barrow, and commissioned between 1983 and 1991.

Trenchant was laid down on October 28, 1985; launched on November 3, 1986 and commissioned January 14, 1989.

Whilst submerged in the Clyde area on November 22, 1990, Trenchant snagged the fishing gear of the MV Antares, which sank as a result.

In 1998 Trenchant's crew had to shut down the boat's reactor whilst at Lisbon, Portugal because of a steam leak.

In the summer of 1999 Trenchant was painted in a blue camouflage scheme in order to take part in visual signature trials. In the few cases in which a submarine is spotted it is usually visually, rather than on radar. In recent years submarines have spent more time operating in shallow, clear waters, such as the Mediterranean and Persian Gulf, than in the Cold War when they operated in the deep and dark Atlantic. Furthermore they spend more time nearer the surface (launching Tomahawk or on reconnaissance missions) than in the past when their main task was to roam the ocean depths hunting other submarines. These patches of blue and cyan paint were therefore designed to break up the outline of the submarine, especially from the air, making it harder to spot.

Click submarine class for technical specifications.