The L-class destroyers were designed as enlarged and improved versions of the preceding J class equipped with dual-purpose guns. They displaced 1,920 long tons (1,951 t) at standard load and 2,675 long tons (2,718 t) at deep load. The ships had an overall length of 362 feet 3 inches (110.4 m), a beam of 37 feet (11.3 m) and a deep draught of 13 feet 9 inches (4.2 m). They were powered by Parsons geared steam turbines, each driving one propeller shaft, using steam for was provided by two Admiralty three-drum boilers. The turbines developed a total of 48,000 shaft horsepower (36,000 kW) and gave a maximum speed of 36 knots (67 km/h; 41 mph). The ships carried a maximum of 567 long tons (576 t) of fuel oil that gave them a range of 5,500 nautical miles (10,200 km; 6,300 mi) at 15 knots (28 km/h; 17 mph). The L class' complement was 190 officers and ratings.^[1]

The ships mounted six 4.7-inch (120 mm) Mark XI guns in twin-gun mounts, two superfiring in front of the bridge and one aft of the superstructure. Their light anti-aircraft suite was composed of one quadruple mount for 2-pounder "pom-pom" guns and six single Oerlikon 20 mm cannon. Later in the war, twin Oerlikon mounts replaced the singles. The L-class ships were fitted with two above-water quadruple mounts for 21-inch (533 mm) torpedoes.^[2] The ships were equipped with 45 depth charges.^[3]

Loyal was laid down on 23 November 1938 by Scotts Shipbuilding and Engineering Company at their Greenock shipyard, launched on 8 October 1941 and completed on 31 October 1942.^[1] She struck a mine on 12 October 1944 and was declared a constructive total loss.

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