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DD-47 Aylwin

The "thousand tonners" resulted from a General Board requirement for a larger destroyers for the FY12 plan for a mass-production ship to quickly supplement the fleet. The specification called for a strong gun armament, including at least one 4" gun to replace the 3" guns of the preceeding classes. A large steaming radius, good heavy weather ability and a larger torpedo battery [of 18 inches]. The construction of eight torpedo-boat destroyers, Nos. 43 to 50, inclusive, was authorized by an Act of Congress approved March 4, 1911. The Bureau of Construction and Repair's smallest, 900-ton light ship displacement, design was accepted for these new destroyers of the DD-47 AYLWIN class.

Four Aylwin (DD-47) class destroyers were laid down in 1912 under contract by the William Cramp and Sons Ship and Engine Building Company of Philadelphia, PA concurrent with the Cassin (DD-43) class. The time of completion for the Ayhvin was twenty-two and one-half months; for the Parker, twenty-three months, and for the Benham, twenty-three and one-half months from the date of contract. The trial displacement was 1,036 tons and the price of each vessel $756,100. The hull is of steel, galvanized in all parts below the water line.

The contract trials were as follows :

• A progressive trial over the measured-mile course, for standardizing the screws. The standardization trials were run over the measured mile off the Delaware Breakwater. On each vessel twenty-six runs were made over the course.
• A full-speed trial of four hours duration in the open sea, in deep water, at the highest speed attainable, the average speed to be not less than 29.5 knots, with the average air pressure in the firerooms not exceeding 6 inches of water and the steam pressure at the high-pressure turbine not to exceed 240 pounds above the atmosphere.
• A fuel-oil and water-consumption trial of four hours duration in the open sea at an average uniform speed of 24 knots as nearly as possible.
• A fuel-oil and water-consumption trial of four hours duration in the open sea at an average speed of 15-l/2 knots as nearly as possible. This trial to be made as nearly as possible under service conditions, with the cruising engines connected up and in use.
• An endurance trial of twenty hours duration in the open sea at an average speed of 15^ knots as nearly as possible, under service cruising conditions, with cruising engines connected up and in use.
• A fuel-oil and water-consumption trial of four hours duration in the open sea with the cruising engines connected up and in use. at an average speed of 12 knots as nearly as possible.

The contract speed was 29.5 knots. They were fitted with Zoelly turbines as opposed to Parsons turbines and achieved slightly slower speeds on trials. Changes required an altered stern, and the Aylwin (DD-47) failed to make her designed speed. These were assigned patrol and convoy escort duties during World War One. They were decommissioned 1921-22 and sold for scrap in 1935.

The 1,000-ton class includes all vessels from the Cassin, No. 43, to and including the Shaw, No. 68. The vessel is of the raised- forecastle type, which is carried aft to frame No. 46. Vessels of this class have a high forecastle extending from the stem to a point just abaft the pilot house, where it breaks off to a low main deck which is extended to the stern. The high forecastle of these vessels plays an important part in their manoeuvring qualities; acting as a permanent jib, which, while helpful under some conditions, is a serious handicap under others. It must always be kept in mind and allowed for, its principal effect being, of course, to make it difficult to bring the vessel up to the wind. Caution must be used when such a vessel is run into a small harbor into which the wind is blowing and where it will be necessary to turn her within the harbor in order to get out. Under such conditions the ship may get beam to wind, and, lacking space to gather headway, refuse to turn into it, and may drift ashore broadside on.

Several narrow escapes are on record resulting from failure to appreciate this feature. In turning with a vessel of this type, it is desirable to turn in such a way as to take advantage of the jib effect instead of having to work against it. The effect of the wind upon the bow is particularly important in going alongside a dock. Destroyers of this class had a large after dead-wood, which resulted in greater steadiness of sea route but produced an excessively large turning circle, the tactical diameter being as great as one thousand yards with rudder angle of twenty degrees.

On the forecastle deck are located the anchors, capstan and pilot house, with flying bridge. A searchlight is carried on a raised platform above the bridge. Aft of frame No. 46 the main deck is a weather deck. From forward aft on this deck are located storeroom, lamp room, wardroom officers' quarters, wardroom, pantry and galley. Aft, in a deck house, are located hatch trunk to crew's quarters, wireless roonvand crew's water closets. A searchlight is carried on top of this house. There are two masts equipped with wireless outfit and signal yards. The customary engine and fireroom telegraphs, gongs, telephones, voice tubes, etc., are fitted for transmitting orders and signaling to the machinery compartments and other parts of the vessel.

The berth deck is divided into two parts. It extends from the stem to frame No. 48 and from frame No. 134 aft, the space between being used for deep fuel-oil tanks, cofferdam, firerooms and engine rooms. Forward are located a storeroom, paint and oil room and crew's quarters, and aft are crew's and petty officer's quarters and storerooms. In the hold are located trimming tanks, chain lockers, storerooms, ammunition and handling rooms, fuel-oil tanks, cofferdam (extending to the main deck and designed to be used as a reserve- feed tank), boiler and engine rooms, oil tanks, ammunition and handling rooms and after trimming tanks. Reserve-feed and fresh-water tanks are located abreast boilers No. 2 and 3. An engineer's storeroom is carried over the fresh-water tank on the starboard side and over the reserve-feed tank on the port side. Coal for galley use is carried in a small bunker located in the port forward corner of No. 1 fire room.

The torpedo tubes are located on the main deck. One is on the port side above frame No. 74 and one on the starboard side over frame No. 95. The remaining two are abreast one another over frame No. 110. On the starboard side about midships are carried a 20-foot whale boat and a 21-foot motor dory, swung in davits. On the port side are a 20-foot whale boat and a 14-foot wherry swung in davits.

The anchor windlass is located on the forecastle deck at frame No. 11. It is of the vertical type, made by the American Engineering Company, of Philadelphia, Pa. The engine is located below on the after bulkhead of the lamp room. The ship is equipped with three steering stations: (1) top of pilot house, steam gear only; (2) pilot house, combined steam and hand gear; (3) hand gear on main deck aft. The steering engine is in the pilot house. It is directly connected through reducing valves to the flushing system and connections are also provided for flushing the stern tubes and oil coolers in case of emergency. The flushing system is taken direct from the fire main and is designed to supply water to the officers' bath, galley and pantry forward and to the crew's water closets and washroom aft.

Fresh water is carried in two tanks, starboard and port, of about 4,000 gallons combined capacity, located in the hold of the ship between frames Nos. 63 and 74. The tanks are provided with filling connections upon each side of the vessel fitted with hose connections. There is also a connection to the distilling plant. A small gravity tank of about 50 gallons capacity is located just aft the pilot house on the forcastle deck, supplying the galley and officers' showers.

The main extends from the after end of the auxiliary room to the forward fireroom and is connected to the boiler, engine and auxiliary rooms, branches to the bilges being fitted with stop-check valves and strainers; where ends of suction pipes are inaccessible strainers are not fitted. Connections are provided to drain compartments below the berth deck forward of and abaft the machinery spaces. The vessel is equipped with the usual system of brass-pipe coil radiators. The steam for this service in the living spaces forward is taken from the auxiliary steam line in the forward fireroom and for the quarters aft is taken from the auxiliary steam line in the engine room.