The Racecourse-class minesweepers were 32 ships delivered to the

Royal Navy The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against ...

during the

First World War World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

. They were built to two related designs as

paddlewheel A paddle wheel is a form of waterwheel or impeller in which a number of paddles are set around the periphery of the wheel. It has several uses, of which some are: * Very low-lift water pumping, such as flooding paddy fields at no more than about ...

coastal

minesweeping Minesweeping is the practice of the removal of explosive naval mines, usually by a specially designed ship called a minesweeper using various measures to either capture or detonate the mines, but sometimes also with an aircraft made for that ...

sloops A sloop is a sailboat with a single mast typically having only one headsail in front of the mast and one mainsail aft of (behind) the mast. Such an arrangement is called a fore-and-aft rig, and can be rigged as a Bermuda rig with triangular ...

under the Emergency War Programme. The vessels were reasonable sea-boats, but lost speed badly in a seaway when the paddle boxes tended to become choked with water. The class is also widely referred to as the ''Ascot'' class and Improved ''Ascot'' class.

Initial design

At the start of the First World War, it soon became clear that a large number of minesweepers would be required to keep coastal shipping routes free from

naval mine A naval mine is a self-contained explosive device placed in water to damage or destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, any ...

s that were laid at night by fast German minelayers. Initially, requisitioned trawlers were used for the task, but they had too deep a draught to operate in some areas, and could be too slow to sever the mooring cables of the mines. Late in 1914, the

Admiralty Admiralty most often refers to: *Admiralty, Hong Kong *Admiralty (United Kingdom), military department in command of the Royal Navy from 1707 to 1964 *The rank of admiral *Admiralty law Admiralty can also refer to: Buildings * Admiralty, Traf ...

hired a number of

paddle steamer A paddle steamer is a steamship or steamboat powered by a steam engine that drives paddle wheels to propel the craft through the water. In antiquity, paddle wheelers followed the development of poles, oars and sails, where the first uses we ...

s which were built to carry tourists to seaside resorts or on pleasure cruises. They were significantly faster than the trawlers and had a shallower draught. Although unable to operate in rough seas, they were judged to be the best solution to the problem and a requirement was issued for a purpose-built class based on the , a Bristol pleasure steamer. Because of their size and simplicity, they could be built in small shipyards without affecting the production of larger warships. The original design was by the

Ailsa Shipbuilding Company Ailsa Shipbuilding Company was a Scottish shipbuilding company based in Troon and Ayr, Ayrshire. History The company was founded in 1885 by the 3rd Marquess of Ailsa along with Peter James Wallace and Alexander McCredie. In 1902 the Ailsa yard ...

. The ships were completed between April and October 1916. Launch dates are shown below. * : January 1916, Ailsa S.B. Co—first of class, also last ship to be lost in World War I. * : January 1916, Ailsa S.B. Co. Converted for passenger use in 1929 as PS ''Queen of Kent''. Converted back to minesweeper in 1939. * : April 1916, Ailsa S.B. Co * : June 1916, Ardrossan Co * : April 1916, Ayrshire D.Y. Co * : April 1916, Ayrshire D.Y. Co * : June 1916 Ayrshire D.Y. Co * : September 1916, Ayrshire D.Y. Co * : May 1916, G. Brown * : February 1916, Clyde S.B. Co. Originally fitted to carry seaplanes. * : April 1916, Dundee S.B. Co. * : June 1916, Dundee S.B. Co. * : March 1916, Dunlop, Bremner * : May 1916, Dunlop, Bremner * : Ferguson Bros. Lost in World War I. * : April 1916,

Fleming & Ferguson Fleming and Ferguson was a Scottish Marine propulsion, marine engineering and shipbuilding company that traded between 1877 and 1969. History 1877–1914 William Y. Fleming and Peter Ferguson (1840–1911) founded the company in Paisley, Renfre ...

* : Goole Co.—lost in World War I. * : March 1916, Hamilton. Originally fitted to carry seaplanes. Converted for passenger use in 1929 as PS ''Queen of Thanet''. Converted back to minesweeper in 1940; served at Dunkirk evacuation and

Normandy landings The Normandy landings were the landing operations and associated airborne operations on Tuesday, 6 June 1944 of the Allies of World War II, Allied invasion of Normandy in Operation Overlord during World War II. Codenamed Operation Neptune and ...

. * : July 1916, A. & J. Inglis * : McMillan—lost in World War I. * : June 1916, Murdoch & Murray * : Ayrshire D.Y. Co.—lost in World War I. * : July 1916, Dunlop, Bremner * : May 1916, McMillan On this type the foremast is stepped before the fore bridges and have derricks abeam of the second funnel.

Improved Racecourse type

These paddle minesweepers were designed by the

, adapted from the Ailsa Company design for the first type. They were completed between January and June 1918. All were built under the Emergency War Programme. * : December 1917, Ailsa S.B. Co. * : February 1918, Ailsa S.B. Co. * : December 1917, Clyde S.B. Co. * : December 1917, Fleming & Ferguson * : March 1918, Fleming & Ferguson * : January 1918, Dunlop, Bremner * : Dunlop, Bremner. Sold as a ferry boat, 1919. * : March 1918, Murdoch & Murray. The foremast on this type is stepped through the chart house, there are two high ventilators abaft fore funnel and no derricks abeam of the second funnel.

Notes and references

External links

The history of HMS Newbury
{{DEFAULTSORT:Racecourse Class Minesweeper Mine warfare vessel classes Ship classes of the Royal Navy