C and D-class destroyer

Duncan with wartime modifications
Class overview
Name:	C and D
Operators:	Royal Navy  Royal Canadian Navy
Preceded by:	B class
Succeeded by:	E and F class
Subclasses:	C, D
Built:	1930–33
In commission:	1932–45
Planned:	14
Completed:	14
Lost:	10
General characteristics (HMS Dainty as built)
Type:	Destroyer
Displacement:	1,375 long tons (1,397 t) (standard) 1,890 long tons (1,920 t) (deep)
Length:	329 ft (100.3 m) o/a
Beam:	33 ft (10.1 m)
Draught:	12 ft 6 in (3.8 m)
Installed power:	36,000 shp (27,000 kW)
Propulsion:	2 × shafts 2 × Parsons geared steam turbines 3 × Admiralty 3-drum boilers
Speed:	36 knots (67 km/h; 41 mph)
Range:	5,870 nmi (10,870 km; 6,760 mi) at 15 knots (28 km/h; 17 mph)
Complement:	145
Sensors and processing systems:	ASDIC
Armament:	4 × 1 – QF 4.7-inch Mk IX guns 1 × 1 – QF 3-inch anti-aircraft gun 2 × 4 – QF .5-inch Vickers Mk III anti-aircraft machineguns 2 × 4 – 21-inch torpedo tubes 20 × depth charges, 1 rail and 2 throwers

The C and D class was a group of 14 destroyers built for the Royal Navy in the early 1930s. As in previous years, it was originally intended to order a complete flotilla comprising eight destroyers—plus a flotilla leader as the ninth unit—in each year. However, only four ships—plus a leader—were ordered under the 1929–30 Programme as the C class. The other four ships planned for the C class were never ordered as an economy measure and disarmament gesture by the Labour government of Ramsay Macdonald. A complete flotilla—the 'D' class—was ordered under the 1930–31 Programme.

The five ships of the C class were assigned to Home Fleet upon their completion, although they reinforced the Mediterranean Fleet during the Italian invasion of Abyssinia of 1935–36 and enforced the Non-Intervention Agreement during the Spanish Civil War of 1936–39. They were transferred to the Royal Canadian Navy (RCN) in 1937–39 and spent most of their time during World War II on convoy escort duties in the Atlantic Ocean. Crescent was sunk when she was accidentally rammed by the British cruiser HMS Calcutta in 1940. Crusader was sunk by a German submarine in 1942, though she had sunk an Italian submarine in 1940. The other ships of the class sank three German submarines during the war. They were all worn out by the end of the war and were scrapped in 1946–47.

The D-class destroyers were initially assigned to the Mediterranean Fleet upon commissioning, but were transferred to the China Station in 1935. Like the C class, most were temporarily deployed in the Red Sea when the Italians invaded Abyssinia, but returned to the China Station when that was over. They were still there when the war began, but reinforced the Mediterranean Fleet shortly afterwards. Five ships were transferred to Home Fleet in December 1939, but Duchess was sunk en route when she was accidentally rammed by the battleship HMS Barham, and Duncan was badly damaged when she collided with a merchant ship, requiring lengthy repairs. Daring was sunk by a German submarine in February 1940. The other two participated in the Norwegian Campaign of April–June, but Delight was sunk by German aircraft in July and Diana was transferred to the RCN as a replacement for the Crescent after she was sunk by the cruiser Calcutta. However, she too was rammed and sunk several months later by a freighter that she was escorting.