In the Royal Navy and other navies of Europe and the Commonwealth of Nations, ships are identified by pennant number. Historically, naval ships flew a flag that identified a flotilla or type of vessel. For example, the Royal Navy used a red burgee for torpedo boats and a pennant with an H for torpedo boat destroyers. Adding a number to the type-identifying flag uniquely identified each ship.
The Laforey class was a class of 22 torpedo boat destroyers of the Royal Navy, twenty of which were built under the Naval Programme of 1912–13 and a further two under the War Emergency Programme of 1914. As such they were the last pre-war British destroyer design. All served during World War I during which three were lost; the survivors were all scrapped in 1921-23.
The C class as designated in 1913 was a heterogeneous group of torpedo boat destroyers (TBDs) built for the Royal Navy in the late-1890s. They were constructed to the individual designs of their builders to meet Admiralty specifications. The uniting feature of the class was a top speed of 30 knots, a "turtleback" forecastle and that they all had three funnels. The funnels were spaced equidistantly and were of equal height, but the central one was thicker.
The Hawthorn M were a class of two destroyers built for the Royal Navy under the pre-war 1913-14 Programme for World War I service.
The D class as they were known from 1913 was a fairly homogeneous group of torpedo boat destroyers (TBDs) built for the Royal Navy in the mid-1890s. They were all constructed to the individual designs of their builder, John I. Thornycroft & Company of Chiswick, to meet Admiralty specifications. The uniting feature of the class was a top speed of 30 knots (56 km/h) and they all had two funnels. In 1913 the nine surviving "30 knotter" vessels with two funnels were retrospectively classified by the Admiralty 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 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, but still were poor seaboats unable to reach top speed in anything but perfect conditions.
The Faulknor class were a class of flotilla leaders that were under construction in the United Kingdom for the Chilean Navy at the outbreak of World War I. Six ships were ordered by Chile, of which the first two were delivered to Chile before the outbreak of the war. The remaining four ships were purchased by the British, taken over and completed for the Royal Navy for wartime service. In common with Royal Navy convention, they were named after famous Royal Navy captains of the past, in this case the members of the Faulknor family.
The Acorn class was a class of twenty destroyers of the Royal Navy all built under the 1909-1910 Programme, and completed between 1910 and 1911. The Acorns served during World War I.
Two Fervent-class destroyers served with the Royal Navy. HMS Fervent and HMS Zephyr were designed and built by Hanna Donald in 1895. The ships displaced 275 tons and were 200 feet (61 m) long. Their locomotive boilers generated 3,850 shp (2,870 kW) which produced a top speed of between 26 and 27 knots. As was usual with ships of their type, they carried one 12-pounder, two torpedo tubes and had a complement of 53 officers and men.
The Myrmidon class destroyer was a class of two destroyers that served with the Royal Navy. Myrmidon and Syren were built by Palmers Shipbuilding and Iron Company as part of the group of boats known as the 'thirty knotters'.
The Star-class destroyer was a class of eight destroyers that served in the Royal Navy: Bat, Crane, Chamois, Fawn, Flirt, Flying Fish, Star and Whiting, were all three-funnelled C-class destroyers, as designated in the reorganisation of classes in 1913. Chamois foundered in 1904; the other ships served during the Great War and were broken up in 1919.
Avon-class destroyer was a class of three destroyers that served in the Royal Navy. These three funnelled 30 knot vessels were redesignated C-class destroyers in the reorganisation of 1913.
The Violet class destroyer was a class of two destroyers that served in the British Royal Navy.
Two Mermaid-class destroyers served with the Royal Navy during the First World War. They were three-funnelled turtle-backed destroyers with the usual Hawthorn funnel tops. Built in 1896–1898, Mermaid and Cheerful were launched by R. & W. Hawthorn, Leslie & Company from their Hebburn-on-Tyne shipyard.
HMS Mermaid was a Hawthorn Leslie three-funnel, 30 knot destroyer ordered by the Royal Navy under the 1896 – 1897 Naval Estimates. She was launched in 1898, served during World War I and was sold for breaking in 1919.
Three Greyhound-class destroyers served with the Royal Navy during the First World War. Built in 1899–1902, Greyhound, Racehorse and Roebuck were three-funnelled turtle-backed destroyers, with the usual Hawthorn funnel tops, built by R. & W. Hawthorn, Leslie & Company at their Hebburn-on-Tyne shipyard.
The Durandal class was a group of four destroyers built for the French Navy between 1896 and 1900, used during the First World War. These vessels were France's first true destroyers rather than torpedo boats. Two units were launched in 1899 while another two followed in 1900. Another four destroyers of the similar Samsun class were laid down in 1906 and completed in 1907 for the Ottoman Navy, they also served in the First World War.
HMS Falcon was a Fairfield three funnel, 30 knot destroyer ordered by the Royal Navy under the 1898 – 1899 Naval Estimates. She spent her life in Home waters, was part of the Dover Patrol during World War I and was lost in a collision on 1 April 1918.
