The M class, more properly known as the Admiralty M class, were a

class Class, Classes, or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used d ...

of 85

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 i ...

s built for the

Royal Navy The Royal Navy (RN) is the naval warfare force of the United Kingdom. It is a component of His Majesty's Naval Service, and its officers hold their commissions from the King of the United Kingdom, King. Although warships were used by Kingdom ...

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

that saw service during

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

. All ships were built to an identical – Admiralty – design, hence the class name. Eighteen other vessels which were officially included within the 'M' class were built to variant designs by three specialist builders – 10 by

Yarrow ''Achillea millefolium'', commonly known as yarrow () or common yarrow, is a flowering plant in the family Asteraceae. Growing to tall, it is characterized by small whitish flowers, a tall stem of fernlike leaves, and a pungent odor. The plan ...

, 6 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 ...

(who also built another 6 to the standard Admiralty design), and 2 by

Hawthorn Leslie R. & W. Hawthorn, Leslie and Company, Limited, usually referred to as Hawthorn Leslie, was a shipbuilding, shipbuilder and locomotive manufacturer. The company was founded on Tyneside in 1886 and ceased building ships in 1982. History The comp ...

; these are covered in other articles. The Admiralty design was based on the preceding L class but modified to produce an increase in speed by approximately . All ships built to the Admiralty design had three identical narrow, circular

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 ...

(this did not apply to the 18 ships built by the specialist yards).

Ships of the pre-war (1913–14) Programme

An original intention to order 20 destroyers in this year's Programme was reduced to 16 vessels.

Three 3 (three) is a number, numeral and digit. It is the natural number following 2 and preceding 4, and is the smallest odd prime number and the only prime preceding a square number. It has religious and cultural significance in many societies ...

destroyers already under construction were purchased from Yarrow,

two 2 (two) is a number, numeral and digit. It is the natural number following 1 and preceding 3. It is the smallest and the only even prime number. Because it forms the basis of a duality, it has religious and spiritual significance in many ...

from Thornycroft and

from Hawthorn Leslie to these builders' individual designs, and these are listed in separate articles. Three further ships had been projected under the Programme – and named ''Marksman'', ''Menace'' and ''Monitor''; however these three ships were cancelled before being contracted to any specific builder (although J. Samuel White & Company, at

Cowes Cowes () is an England, English port, seaport town and civil parish on the Isle of Wight. Cowes is located on the west bank of the estuary of the River Medina, facing the smaller town of East Cowes on the east bank. The two towns are linked b ...

were the intended builder), in favour of two ''Marksman''-class leaders. Thus just six vessels were built to the Admiralty design under the 1913–14 Naval Programme. These differed from the wartime vessels by being 1,010 tons full load, with slightly smaller dimensions.

Ships of the Emergency War Construction Programme

All the following vessels were ordered in five batches as part of the

War Emergency Programme War is an armed conflict between the armed forces of State (polity), states, or between governmental forces and armed groups that are organized under a certain command structure and have the capacity to sustain military operations, or betwe ...

. Wartime builds omitted the cruising turbines originally specified and carried by the pre-war sub-group. The funnel heights were also raised compared with the pre-war vessels, and the second 4 in gun was mounted on a bandstand, as with the earlier L-class destroyers. ''Partridge'', ''Norman'', ''Maenad'', ''Ophelia'' and ''Observer'' were later fitted to carry a

kite balloon A kite balloon is a tethered balloon which is shaped to help make it stable in low and moderate winds and to increase its lift. It typically comprises a streamlined envelope with stabilising features and a harness or yoke connecting it to the mai ...

1st War Programme

Sixteen vessels were ordered in September 1914 (as well as four of the Yarrow M class), but part of their cost was met by the provision in the 1914–1915 Programme for ten destroyers.

2nd War Programme

Nine further vessels were ordered in early November 1914 (as well as one further Yarrow M class).

3rd War Programme

Twenty-two further vessels were ordered in late November 1914.

4th War Programme

Sixteen further vessels were ordered in February 1915 (as well as two more of the Thornycroft M class). The eight last-named below of these were of the Repeat M subgroup with raking stems compared with the straight stems of the previous sub-group, and the bows were more flared to improve seakeeping qualities.

5th War Programme

Eighteen final vessels were ordered in May 1915 (as well as two of the Thornycroft M class and two of the Yarrow M class). However, two of the eighteen were fitted with geared turbines and became the prototypes for the Admiralty R class destroyers (these were the ''Radstock'' and ''Raider'', and are listed with the R class). The other sixteen were all to the Admiralty design were of the Repeat M subgroup with raking stems apart from the two ships ordered from White as ''Redmill'' and ''Redwing'', which were completed to the earlier 'M' Class design and were renamed ''Medina'' and ''Medway'' while building.

Notes

Bibliography

* * * * * ''Jane's Fighting Ships, 1919'', Jane's Publishing. {{WWI British ships M class destroyer Admiralty Ship classes of the Royal Navy