FLEET AUXILIARY VESSELS. In addition to the fighting units—battleships, cruisers, destroyers, etc.—which go to make up a fleet, a modern navy, in war time, requires an array of auxiliary vessels and small craft. The World War produced many varieties of such auxiliaries; some for service with the main forces, but many to perform special functions, called for by the German submarine and mine-laying campaign, or for use in con nection with landing operations. In the first category were the vessels required to carry oil fuel, ammunition, provisions and stores from the naval establishments to the fleet bases; in gen eral, merchant ships were adapted for these services. In addition, repair ships fitted with complete workshops were employed at the fleet bases. For other services, existing ships were adapted or new vessels were built. Space permits mention of the more important types only.
Merchant ships of large and medium size were fitted out by the British Admiralty as armed merchant cruisers. These vessels performed invaluable service in dealing with the German armed liners which were at large at the outbreak of war, a notable event in this connection being the sink ing of the "Cap Trafalgar" by the "Carmania" on Sept. 14, 1914. At a later stage of the war the A.M.C.'s were principally employed on convoy duty across the Atlantic. The standard fighting equip ment of the largest of these was two 6in. B.L. guns, six 6in. Q.F. guns, two 11 in. howitzers, two 6pdr. or other anti-aircraft guns and four depth charges. In order to relieve some of the destroy ers for essential duty with the fleet, certain vessels of cross chan nel type were converted into armed boarding vessels.
Sloops classified as convoy sloops were built to resemble merchant ships. The guns were in concealed positions, and many of these vessels carried kite balloons to assist them in locating enemy submarines. As auxiliaries to these and to other fighting vessels carrying kite balloons, one or two merchant ships were taken over and fitted with powerful hydrogen plants for inflating the kite balloons. Merchant ships spotting with these balloons co-operated with the land forces during the Gallipoli campaign. They also did useful work in the Adriatic.
In 1915, 15 vessels of whaler type were built for the convoying of merchant vessels of slow speed. The whaler type was considered to be desirable (and proved to be so on service) on account of its good manoeuvring qualities, which enabled it to cope with enemy submarines despite its slow speed. These vessels were 13 2 f t. long, 2 5 f t. beam, 8-ft. mean draught and carried one 12pdr. gun. They were well subdivided by bulk heads and decks to give them the maximum safety in case of underwater damage. Their gun could be effectively concealed, and a mock harpoon gun was fitted forward as an additional dis guise to their real character.
No reference to the auxiliary vessels used during the war would be complete without mention of the famous Q ships, and their campaign against the enemy submarines. Mer chant vessels, both sailing and steam driven and of many different types, were fitted out with guns and depth charges which were cleverly concealed behind dummy deck houses, boats, etc. They went to sea with the deliberate object of luring submarines into attacking them, and the crews would entice the enemy to close quarters by making a show of abandoning the ship. At the critical moment the hidden guns would be revealed and fire opened on the submarine. The Q-ships were manned by naval personnel dis guised as ordinary merchant seamen and their heroic deeds were responsible for the destruction of a considerable number of sub marines, although the ships themselves did not emerge from their campaign without numerous losses.
Mine-Sweepers and Trawlers.—The extensive minelaying operations of the Germans called for the provision of many mine sweeping vessels. A number of smaller merchant ships were taken over for this purpose at the outset of the war, but it soon became necessary to build vessels specially suited to mine-sweeping as the demand became greater. Altogether about zoo of these vessels were built, merchant practice being adopted in order to simplify their construction and to bring them within the capacity of the smaller shipyards. They were of 75o tons displacement, and the i,800h.p. machinery provided enabled them to reach a full speed of 17 knots. They proved capable of remaining afloat after the most severe damage from mines. Ordinary steam fishing trawlers were also used for mine-sweeping.
P-Boats.—Patrol boats of the "P" class were designed to relieve destroyers of such duties as patrolling, escort work and operations against submarines. High speed was not a necessity for the particular work which they had to undertake, but their 22 knots was sufficient to overtake submarines, and their top hamper was kept as low as possible to avoid their being easily visible. They were of 600 tons displacement and developed full speed with 3,800h.p. geared turbines, and carried one 4in. and one 2pdr. gun and two i4in. torpedo tubes. They proved very economical and efficient boats, especially in anti-submarine work.
Coastal Motor Boats.—A great deal of useful work in attack ing submarines, in patrolling the coast and in operations against enemy bases on the Belgian coast was performed by the large fleet of coastal motor boats which were built during the war. These boats varied from 4oft. in length in the earlier types to 7of t. in the later design and the speeds varied from 3o to 37 knots. They were fitted with Lewis guns and depth charge apparatus and could carry alternatively either a mine or one or two i8in. tor pedoes. They took part in many operations attended with great risks, notably in the raids on Zeebrugge and Ostend.
The Admiralty also de signed some fast fleet oilers which could carry 5,000 tons of oil at a speed of 15 knots. Many other types of auxiliary ships were designed and constructed including ammunition ships, gunboats for patrol work and also of special type for work in Mesopo tamia, self-propelled lighters for landing troops, guns, etc., and blockships. In the last-named class are the "Vindictive" and her sister blockships which were used in the raids on Zeebrugge and Ostend. (See BELGIAN COAST OPERATIONS.) Sloops, minelayers, minesweepers and fleet supply ships are necessary auxiliaries to modern navies, and are to be found in varying strength but similar in type to those described in the fleets of the principal sea powers. (See also MINES, MINELAYING AND MINESWEEPING.) (W. J. B.) See Jane's Fighting Ships; Brassey's Naval and Shipping Annual.
