The Captain class frigate was a designation given to 78 frigates of the Royal Navy, constructed in the United States of America, launched in 1942–1943 and delivered to the United Kingdom under the provisions of the Lend-Lease agreement (the program under which the United States of America supplied the United Kingdom and other Allied nations with materiel between 1941 and 1945), they were drawn from two subclasses of the American Destroyer Escort (originally British Destroyer Escort) classification; 32 from the Evarts subclass and 46 from the Buckley subclass. On reaching the UK the ships were substantially modified by the Royal Navy making them distinct from the US Navy Destroyer Escort ships.
Captain class frigates acted in the roles of convoy escorts, anti-submarine warfare vessels, coastal forces control frigates and headquarters ships for the Normandy landings. During the course of World War II this class participated in the sinking of at least 34 German submarines and a number of other hostile craft with 15 of the 78 Captain class frigates being either sunk or written-off as a Constructive Total Loss.
In the Post-war period nearly all of the surviving Captain class frigates were returned to the US Navy as quickly as possible to reduce the amount payable under the provisions of the Lend-Lease agreement, with the last Captain class frigate to be returned to United States custody in March 1956.
The Evarts subclass had diesel-electric machinery, based on an arrangement used for submarines. There were two shafts. Four Winton 278A 16-cylinder engines, with a combined rating of 7,040 bhp (5,250 kW), driving General Electric Company (GE) generators (4,800 kW) supplied power to two GE electric motors, with an output of 6,000 shp (4,500 kW), for 20 knots (37 km/h). It had been intended to provide a further set of this machinery, for an output of 12,000 shp (8,900 kW) to make the design speed of 24 knots (44 km/h), but hull production greatly outstripped that of the machinery, therefore only one set of machinery was used per ship.
To make the designed speed, the Buckley subclass had turbo-electric machinery. Two Foster-Wheeler Express "D"-type water-tube boilers supplied steam to GE 13,500 shp (10,070 kW) steam turbines and generators (9,200 kW). Electric motors for 12,000 shp (8,900 kW) drove the two shafts each fitted with a three-bladed propeller of solid manganese-bronze that was 8.5 feet (2.6 m) in diameter. This all electric drive-train was considered particularly innovative at the time (although the Catherine class minesweepers had a similar arrangement).
| General characteristics | |
|---|---|
| Displacement: | 1,140 long tons (1,158 t) (Evarts) 1,400 long tons (1,422 t) (Buckley) |
| Length: | 289 ft 6 in (88.24 m) (Evarts) 306 ft (93 m) (Buckley) |
| Beam: | 35 ft (11 m) (Evarts) 36 ft 9 in (11.20 m)(Buckley) |
| Draft: | 9 ft (2.7 m) |
| Speed: | 20 knots (37 km/h; 23 mph) (Evarts) 24 knots (44 km/h; 28 mph) (Buckley) |
| Range: | 5,000 nautical miles (9,300 km; 5,800 mi) at 15 knots (28 km/h; 17 mph) (Evarts) 5,500 nautical miles (10,200 km; 6,300 mi) at 15 knots (28 km/h; 17 mph) (Buckley) |
| Complement: | 156 (Evarts) 186 (Buckley) |
| Sensors and processing systems: | SA & SL type radars Type 128D or Type 144 series Asdic MF Direction Finding antenna HF Direction Finding Type FH 4 antenna |
| Armament: | 3 × 3 in (76 mm) /50 Mk.22 guns 1 × twin Bofors 40 mm mount Mk.I 7-16 × 20 mm Oerlikon guns Mark 10 Hedgehog A/S projector Depth charges QF 2 pounder naval gun |
