Acorn-class destroyer

After the coal-burning {{sclass|Beagle|destroyer|4}} of the 1908–1909 shipbuilding programme, the British Admiralty decided to return to oil-fuelled machinery, as pioneered in the {{sclass2|Tribal|destroyer|4||1905}} of 1905 and {{HMS|Swift|1907|6}} of 1907, for the destroyers to be built under the 1909–1910 programme, which became the Acorn class.Gardiner and Gray 1985, p. 74. This change allowed a smaller vessel than the Beagles even with an increase in armament.Brown 2010, p. 69.Manning 1961, p. 57.

While the detailed design of earlier destroyer classes was left to the builders resulting in individual ships differing considerably, this changed for the Acorns, where a standard hull design was used, allowing more shipyards to bid for orders, thus driving down costs, while reducing the time and effort required for the Admiralty to check and approve each builder's designs. Machinery design, however, was still left to the builders, although it had to fit into the space allowed in the standard design.Brown 2010, p. 68.Friedman 2009, pp. 118–119. They had a reasonably uniform appearance, with three funnels, a tall, thin fore funnel, a short, thick central and a short narrow after stack.Friedman 2009, p. 119.

The ships were {{convert|240|ft|0|in|m}} long between perpendiculars and {{convert|246|ft|0|in|m}} overall, with a beam of {{convert|25|ft|3|in|m}} and a draught of between {{convert|7|ft|4+1/2|in|m}} and {{convert|8|ft|10|in|m}} depending on load. Displacement was {{convert|760|LT|t}} normal and {{convert|855|LT|t}} full load.Friedman 2009, p. 295. Nineteen of the twenty ships of the Acorn class had three propeller shafts driven by Parsons steam turbines, fed by four boilers (White-Forster boilers in the three J. Samuel White-built ships, ({{HMS|Redpole|1910|2}}, {{HMS|Rifleman|1910|2}} and {{HMS|Ruby|1910|2}}), Yarrow boilers in the remaining ships), with the boiler out-takes routed to three funnels. The remaining ship of the class, the John Brown & Company-built {{HMS|Brisk|1910|2}}, had a two shaft arrangement powered by Brown-Curtis impulse turbines. The ships were required to reach {{convert|27|kn}}, the same speed as the Beagle class, which was expected to need {{convert|13500|shp|kW}}.Friedman 2009, p. 122.{{#tag:ref|The power needed to reach the specified speed was greater than expected in some ships, with {{HMS|Acorn|1910|2}} needing {{convert|15072|shp|kW}} during sea trials to reach {{convert|27.335|kn}}. Other ships were faster, with {{HMS|Larne|1910|2}} reaching {{convert|28.723|kn}} with {{convert|14900|shp}} and {{HMS|Ruby|1910|2}} reaching {{convert|30.335|kn}} with {{convert|16776|shp|kW}}.|group=lower-alpha}} The ships had a crew of 72 officers and men.

The revised machinery layout freed up deck space, allowing heavier armament to be carried.Friedman 2009, p. 118. Gun armament consisted of two BL 4 inch naval gun Mk VIII guns,{{#tag:ref|The abbreviation BL stood for Breech Loading. In British use it also indicated that the gun used a bagged charge, with QF (Quick Firing) meaning that the gun used a charge enclosed in a metal cartridge case.|group=lower-alpha}} one on the ship's forecastle and one aft, and two 12-pounder (76 mm) QF 12 cwt guns{{#tag:ref|"Cwt" is the abbreviation for hundredweight, 12 cwt referring to the weight of the gun.|group=lower-alpha}} carried in the waist position between the first two funnels. Unlike the Beagles, the forecastle gun was not raised on a bandstand, as it was felt that in heavy seas this generated additional spray. As with the Beagles, torpedo armament consisted of two British 21 inch torpedo torpedo tubes, with two reload torpedoes carried, although the tubes were longer, allowing more modern torpedoes to be carried. The torpedo tubes were aft of the funnels, mounted singly with a searchlight position between them. Wartime modifications included the addition of a 3-pounder (47 mm) Vickers anti-aircraft gun and depth charges.Friedman 2009, p. 147.

The Acorns were followed, in the 1910-11 Programme, by the {{sclass|Acheron|destroyer|4}} (later known as the 'I' class).

File:HMS Hope.jpg

On commissioning, between December 1910 and February 1912, the ships of the class joined the 2nd Destroyer Flotilla of the Royal Navy's Home Fleet, replacing {{sclass2|River|destroyer|2||1903}}s. They were officially redesignated the H class in October 1913 as part of a general re-designation of the Royal Navy's destroyers.Gardiner and Gray 1985, pp. 18, 74.

The ships of the class remained members of the 2nd Flotilla on the outbreak of the First World War, when the flotilla became part of the Grand Fleet. Some ships of the class were sent to the Mediterranean in 1915, with all surviving ships eventually being transferred there. Two of the class ({{HMS|Minstrel|1910|2}} and {{HMS|Nemesis|1910|2}}) were loaned to the Imperial Japanese Navy in 1917, being renamed Sendan and Kanran, and were returned in 1919. Three ships of the class were lost during the war, one ({{HMS|Goldfinch|1910|2}}) ran aground at Start Point in Sanday, one of the Orkney Islands, in 1915, while the other two ships, {{HMS|Comet|1910|2}} and {{HMS|Staunch|1910|2}}, were sunk by enemy submarines in the Mediterranean.

Following the end of the war, the Royal Navy quickly disposed of large numbers of older ships, including the Acorn class. All remaining ships of the class had been sold for scrap by the end of 1921.Gardiner and Gray 1985, p. 5.

{{reflist|group=lower-alpha}}

{{reflist|30em}}

• {{cite book|last=Brown|first=David K.|title=The Grand Fleet: Warship Design and Development 1906–1922|year=2010|publisher=Seaforth Publishing|location=Barnsley, UK|isbn=978-1-84832-085-7}}
• {{cite book|last=Cocker|first=Maurice|title=Destroyers of the Royal Navy, 1893-1981|year= 1983|publisher=Ian Allan|isbn= 0-7110-1075-7}}
• {{cite book|last1=Dittmar|first1=F.J.|last2=Colledge|first2=J.J.|title=British Warships 1914–1919|year=1972|publisher=Ian Allan|location=Shepperton, UK|isbn=0-7110-0380-7}}
• {{cite book|last=Friedman|first=Norman|title=British Destroyers: From Earliest Days to the Second World War|year=2009|publisher=Seaforth Publishing|location=Barnsley, UK|isbn=978-1-84832-049-9}}
• {{cite book|editor1-last=Gardiner|editor1-first=Robert|editor2-last=Gray|editor2-first=Randal|title=Conway's All The World's Fighting Ships 1906–1921|year=1985|publisher=Conway Maritime Press|location=London|isbn=0-85177-245-5}}
• {{cite book |last = Manning | first =T.D. |title = The British Destroyer |publisher = Putnam| date = 1961 | location = London|oclc=6470051}}
• {{cite book|last=Moore|first=John|title=Jane's Fighting Ships of World War I|year=1990|publisher=Studio|location=London|isbn=1-85170-378-0}}

{{Commons category}}

{{Acorn class destroyer}}

{{WWI British ships}}

{{WWI Japanese ships}}

Category:Destroyer classes

Category:Ship classes of the Royal Navy