HMS Londonderry was a Rothesay-class (Type 12) anti-submarine frigate of the British Royal Navy, in service from 1960 to 1984. She measured 370 feet (112.78 meters) in length overall, with a beam of 41 feet (12.50 meters) and a draught of 13 feet 6 inches (4.11 meters). Her propulsion system consisted of two Babcock & Wilcox water-tube boilers feeding steam at 550 psi and 850°F into twin geared steam turbines, which drove two large 2-foot-diameter propellers, producing a top speed of approximately 29.5 knots. The ship's complement was about 212 officers and men. Originally armed with a twin 4.5-inch Mark 6 gun mount at the bow, HMS Londonderry was designed for anti-submarine warfare, equipped with twelve 21-inch torpedo tubes for Mark 20E Bidder homing torpedoes and two Limbo anti-submarine mortars. However, the torpedo tubes were soon removed due to the obsolescence of the Bidder torpedoes. Her initial anti-aircraft armament included a single Bofors 40 mm gun, with plans for a twin 40 mm mount which were replaced by the Seacat missile system during her 1957 construction. Her sensor suite comprised Type 293Q surface/air search radar, Type 277 height-finding radar, and a Mark 6M fire control system with Type 275 radar for the main guns, along with navigation and sonar systems including Type 174 search, Type 170 fire control sonar, and Type 162 classification sonar. In the late 1960s, HMS Londonderry underwent a significant modernization, adding a helicopter hangar and flight deck for a Westland Wasp helicopter, along with Seacat missile launcher, updated radar systems, and additional anti-aircraft defenses. Post-modernization, she served in various deployments, including the Far East, the Beira Patrol, and rescue operations such as saving Cuban refugees. Later in her career, she was refitted as a trials ship and eventually served as a Dartmouth Training Ship until her decommissioning in 1984. She was finally sunk as a target in 1989. Throughout her service, she traveled approximately 125,500 km, visiting 50 ports across 35 countries, and participated in numerous operational and training exercises.

This description has been generated using GPT-4.1-NANO based on the Vessel's wikidata information and then modified by ShipIndex.org staff.