The powerful small ships of the Black Swan class (thirteen units built) had little in common with other sloops of the Royal Navy, most of which came to be seen as minesweepers or simply patrol boats. The first vessels, however, received devices for sweeping mines, although it is difficult to understand why such expensive and useful boats were supposed to perform this type of function; the space and the weight in the heights that the transport of this material required moreover considerably reduced their anti-submarine capacity. The twenty-four units of the Modified Black Swan class no longer deployed this equipment, which allowed them to become excellent specialized submarine hunters.
The origins of the Black Swans traced back to HMS Enchantress, launched in 1934. Although capable of carrying out minesweeping operations, this vessel had gun armament comparable to that of a destroyer. The third ship in the class, HMS Bittern (launched 1938) featured the installation of three vertical-firing 101.6mm mounts and a new rudder system. This arrangement proved so promising that the three units of the following series, the Egret class, were equipped with four of these mountings, which was however clearly too ambitious for boats of slightly increased dimensions. The Black Swans, outwardly very similar to the earlier ones, were a bit larger and had a quadruple '2' piece mounted in the Y position, from where it was later removed to improve the quarterdeck layout, and also because short-range armament was strengthened with the greater availability of 20mm and 40mm guns.
The Black Swans had a massive superstructure, probably due to the desire to produce a smooth roll to make them better anti-aircraft platforms. Oddly, they did not achieve very good results against aircraft (four of the five buildings destroyed during the conflict were sunk by bombs), probably because, unlike the Hunts who deployed the same weapons, they were slow and lacked liveliness.
Features
Black Swan Class
Displacement :1,300 t standard.
Dimensions :
length , 91.30 m
width , 11.43m;
draught, 2.59 m.
Engine apparatus :2 geared steam turbines developing 3,600 hp and driving 2 art Speed :19.5 knots.
Range:14,825 km at 12 knots.
Armament :3 mixed twin 101.6 mm guns, 1 “Pompom” of “2”, 6 twin AA guns of 2C and ASM grenades.
Crew :180 officers and sailors,