The D class as they were known from 1913 was a fairly homogeneous group of

torpedo boat destroyer In naval terminology, a destroyer is a fast, maneuverable, long-endurance warship intended to escort larger vessels in a fleet, convoy, or carrier battle group and defend them against a wide range of general threats. They were conceived in ...

s (TBDs) built for the

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in the mid-1890s. They were all constructed to the individual designs of their builder, John I. Thornycroft & Company of

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, to meet Admiralty specifications. The uniting feature of the class was a top speed of and they all had two

funnels A funnel is a tube or pipe that is wide at the top and narrow at the bottom, used for guiding liquid or powder into a small opening. Funnels are usually made of stainless steel, aluminium, glass, or plastic. The material used in its constructi ...

Classification

In 1913 the nine surviving "30 knotter" vessels with two funnels (all ten had been built by Thornycroft, but ''Ariel'' was lost before their renaming as D class) were retrospectively classified by the

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as the D class to provide some system to the naming of HM destroyers. In the same way those with three funnels were classified as the C-class and those with four funnels as the B-class. All these vessels had a distinctive "turtleback"

forecastle The forecastle ( ; contracted as fo'c'sle or fo'c's'le) is the upper deck (ship), deck of a sailing ship forward of the foremast, or, historically, the forward part of a ship with the sailors' living quarters. Related to the latter meaning is t ...

that was intended to clear water from the bow, but actually tended to dig the bow in to anything of a sea, resulting in a very wet conning position. They were better constructed than their A-class forebears (the "26 knotter" and "27 knotter" groups), but still were poor seaboats unable to reach top speed in anything but perfect conditions.

Design

They generally displaced 355 to 370 tons and had a length of . All were powered by triple expansion steam engines for and had coal-fired

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s, except for the final vessel (''Stag'') in which the engine power was slightly raised to . Armament was one QF 12-pounder gun on a bandstand on the forecastle, five QF 6-pounder guns (two sided abreast the

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, two sided between the funnels and one on the

quarterdeck The quarterdeck is a raised deck behind the main mast of a sailing ship. Traditionally it was where the captain commanded his vessel and where the ship's colours were kept. This led to its use as the main ceremonial and reception area on bo ...

) and two single tubes for 18-inch (450 mm) torpedoes. Due to the successful development of their previous 26 and 27-knot torpedo boat destroyers, John I Thornycroft & Company developed their two funnel design for the 1894/1895 – 1897/1898 building programs. The ships were considered an incremental improvement to the previous 27-knot design of the 1893/94 program. This design would be used for all follow-on turtleback ships under the 30-knot specification. The 30-knot torpedo boat destroyers built by Thornycroft were referred to as two funnel – 30-knot ships and were not assigned a class name at the time. They featured a large fore-bridge, mast halfway between bridge and fore funnel, turtleback cut-away bow, large round stern, both torpedo tubes on

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aft of second funnel and two funnels. They had a Thornycroft stern with the rudder not visible. They had dual rudders which made them very responsive to the helm.

Ships

All ten of the D class were built by

Thornycroft Thornycroft was an English vehicle manufacturer which built coaches, buses, and trucks from 1896 until 1977. History In 1896, naval engineer John Isaac Thornycroft formed the Thornycroft Steam Carriage and Van Company which built its f ...

, in four batches. *First group (ordered 10 May 1895 under 1894–1895 programme); ** ''Desperate'' ** ''Fame'' ** ''Foam'' ** ''Mallard'' - ordered 30 May ''vice'' 10 May *Second group (ordered 23 January 1896 under 1895–1896 programme) - identical with the preceding group; ** ''Angler'' ** ''Ariel'' *Third group (ordered 21 April 1896 under 1896–1897 programme) - modified from the previous six vessels;The plans for this design were also used for building the Japanese destroyers '' Murakumo'' (Yard Number 329), '' Shinonome'' (330), '' Yūgiri'' (331), ''

Shiranui is an atmospheric ghost lights, atmospheric ghost light told about in Kyushu. They are said to appear on days of the noon moon such as the (29th or 30th day) of the seventh month of the lunisolar Japanese calendar when the wind is weak, in t ...

'' (332), '' Kagerō'' (337) and '' Usugumo'' (338), comprising the ''Murakumo'' Class. ** ''Coquette'' ** ''Cygnet'' ** ''Cynthia'' *Last group (ordered 7 September 1897 under 1897–1898 programme) - with slightly enhanced engine power; ** ''Stag''

Key dates and fates

Notes: (a) ''Desperate'' had a final run over the measured mile on 4 September 1896. Altogether, this vessel completed nine successive preliminary trials.

Notes

Bibliography