BB-32 Wyoming Class
The Wyoming class numbered two ships, BB-32 Wyoming and BB-33 Arkansas, both built along the Delaware River. Designed after the U.S. Atlantic Fleet's 1907-09 World cruise, the two Wyomings were near-sisters of four Florida- and Texas-class battleships, which included the before-mentioned vessels as well as USS Utah and USS New York. Arkansas and its near-sisters represented the first "modern" class of U.S. battleships. The American "dreadnoughts" were designed to win sea battles through superior fire power and speed. The Wyoming class ships were nearly twenty-percent larger than their immediate predecessors, with more extensive armor protection. A flush-deck hull, raking in an essentially straight line from a high bow to a rather lower stern, allowed the midships five-inch secondary battery to be located higher (and therefore dryer) than in earlier ships. This same general arrangement would be repeated in the next class, the New Yorks of 1911, though with a change to fourteen-inch guns. The Wyoming class were the last US battleships to be driven by direct drive steam turbines. They were powered by newly developed steam turbines operating at then unheard-of speeds.
USS Arkansas (BB-33) was a riveted steel vessel 562 feet long overall, with a waterline length of 555-1/2 feet, a maximum beam of 106 feet, and a draft of 29 feet, 11-1/2 inches. Arkansas originally displaced 23,066 tons standard; the addition of deck armor and torpedo blisters between 1925-1927 increased the battleship to 26,100 tons standard displacement. The ship had 1,448 crew and was fitted as a flagship. Arkansas was heavily armored above the waterline; an 9-to-11-inch armor belt protected the ship amidships. The turrets were covered by 9 to 12 inches of armor plate. The hull was double-bottomed except in the machinery spaces, where three bottoms were fitted. The battleship received additional deck armor between 1925-1927; 3.5 inches of armor covered the top of the armor belt. This increased the displacement by 3,000 tons.
The main battery consisted of twelve 12-inch/50 caliber guns, twin mounted in six turrets--two forward, two amidships, and two aft. The secondary battery consisted of sixteen 5-inch/51 caliber guns in casemates. Between 1925-1927 some of these latter positions, which were wet in a seaway, were moved up to the main deck, and in 1942, ten of the 5-inch guns were removed, leaving three 5-inch guns in midships casemates (known aboard ship as the air castles) on each beam of the ship. Arkansas mounted two 21-inch torpedo tubes, which were later removed. The battleship's original antiaircraft battery comprised eight 3-inch/50 caliber guns. In 1942 additional AA guns were added; as of 1945, Arkansas mounted nine quad 40mm Bofors guns and 28 single-mount 20mm Oerlikon guns. In its 1925-1927 refit, Arkansas also received an airplane catapult atop turret No. 3 and three spotter aircraft.
Arkansas' four screws were driven by Parsons turbines and four White-Forster boilers which developed 28,000 shaft horsepower at 20.5 knots. The boilers vented into two stacks; between 1925-1927 when Arkansas was reboilered, a single stack replaced the original two. The coal-burning boilers installed in 1912 were replaced at that time with oil-burners; Arkansas' bunkers carried 5,425 tons of fuel oil. Other topside changes included replacing the cage mast with a low tripod between No. 4 and No. 5 turrets. In 1942, the ship was fitted with a tripod foremast aft of the bridge; the bridge itself was reconstructed at the same time. Fire control stations were located atop each mast in the enlarged tops.
The dreadnought design of 1906 armed the Michigan and South Carolina with 8 12-inch guns in 4 central turrets. The Delaware and North Dakota, designed in 1907 and commissioned within three years, carry 5 similar turrets with a displacement of 20,000 tons and steam 21 knots. The two Wyomings had two more twelve-inch guns, for a total of a dozen, mounted in six twin turrets, the largest number of individual turrets in any U.S. "all-big-gun" battleship. The Florida and Utah, commissioned in 1911, had 16 5-inch guns as an anti-torpedo battery in place of the Delaware's 14; and the Arkansas and Wyoming, completed in 1912, had 21 of these guns besides six pairs of 12-inch guns mounted in turrets.
The Michigan, 16,000 tons, has a mean draft of 24 ft.; the North Dakota, 20.000 tons, 26 ft. 11 in.; the Wyoming. 26.000 tons, about 28 ft, 6 in. The Michigan is 450 ft. long on the load water line; the North Dakota, 610 ft.; the Wyoming, 550 ft. The Michigan has an extreme breadth at load water line of 80 ft. 2g in.; the \orth Dakota, 85 ft. 2 in.; the Wyoming, 93 ft. 28 in.
In 1907 the Delaware and North Dakota were laid down, Curtis turbines fitted in the North Dakota and reciprocating engines of the latest type in the Delaware, the reciprocating engines of the Delaware giving better results in cruising than the turbines of her consort. Parsons turbines were adopted for the four battleships next laid down. The first two, the Florida and Utah, commenced in 1909, are very similar to the Delaware, but of 21,825 tons displacement and 28 ft 6 in. mean draught. The second pair. the Arkansas and Wyoming, begun in 1910, were of much greater displacement, viz., 26,000 tons; 8100 tons greater than the Dreadnought.
Their coal-fired boilers allowed both Wyoming and Arkansas to operate with the British Grand Fleet in the then-oil-deprived North Sea during World War I. The first problem connected with the design of a boiler plant is to determine accurately the maximum number of pounds of steam that will be used by the various engines, pumps, and other parts of the plant which will have to be supplied. As 1 square foot of heating surface should be allowed in shell boilers for every 3 pounds of water to be evaporated into steam from and at 212 degrees in an hour's time. With water-tube boilers the heating surface can be obtained by dividing the number of pounds of water to be evaporated into steam from and at 212 degrees per hour by 3.4. With this proportion and sufficient draft and grate surface to burn the necessary amount of fuel, a boiler can easily be forced 33 per cent over this capacity and maintain a good efficiency.
Some boilers can do much better than this. In a test of Babcock and Wilcox marine boilers, by the U. S. Navy Department, for the battleship Wyoming, the efficiency was 74.3 per cent and 69.1 per cent with an evaporation of 3.88 pounds and 10.52 pounds of water per square foot of heating surface per hour respectively.
Tests were made on the United States battleship Wyoming with coal as fuel, oil as fuel, and a combination of coal and oil. The oil was sprayed over the coal fire, a flat flame being secured by adjusting the admission of air. The capacity of the boilers can be increased by using oil in this manner, but efficient results are obtained only when either fuel is used alone.
Boat crane motors as furnished for the USS Arkansas and Texas involve material departures from previous practice, in that the motors in conjunction with the system of control are adapted to permit entire elimination of the mechanical brake which is customarily ussd to hold the load during lowering, also the auxiliary brake customarily used for rapidly handling light loads such as coaling the ship, etc.
Before the war, they served in the Atlantic Fleet and afterwards in both the Atlantic and Pacific, with modernization following in 1925-27. That work gave them broader beams, greater displacement and thicker deck armor. New oil-burning boilers and newer gunfire controls produced a change in silhouette to a single smokestack and only one "basket" mast. Some of their five-inch guns were remounted in the superstructure.
In 1931, Wyoming was converted to a training ship, with her armor and six of the twelve-inch guns removed. Arkansas was also largely employed on training service, though she formally remained a battleship. The two ships served through World War II. Arkansas, refitted with a new tripod foremast, performed escort and training duties in 1941-44 and conducted shore bombardment at Normandy, Southern France, Iwo Jima and Okinawa after that. Wyoming was a gunnery training ship throughout the conflict. In 1944, she lost all her big guns, and later her "basket" foremast. Now carrying more dual-purpose five-inch gun mounts, she was better suited for urgently-needed anti-aircraft training. In 1945-47, she was also employed as an experimental gunnery ship and then scrapped. Arkansas was sunk as a target in the July 1946 Bikini atomic bomb tests.
Arkansas was selected as a target vessel for Operation Crossroads and was prepared for the bomb tests at Terminal Island, California, before steaming from Pearl Harbor on May 8, 1946. Arkansas left Pearl on May 20 and arrived at Bikini on May 29, 1946. Arkansas was moored off the port beam of USS Nevada, the target ship for the Able test on July 1, 1946. The battleship was "one of the three major combatant ships within one half mile of the zeropoint."  The ship was the site of the maximum measured radioactive contamination from the Able test; a pool of water on Arkansas was measured at eight roentgens per eight hours. Arkansas was moored within 500 feet of the detonation point for the Baker Test of July 25, 1946; it was the closest of the target vessels with the exception of the vessel that suspended the bomb, LSM-60. The detonation is popularly believed to have lifted the battleship vertically out of the water within the blast column. Careful analysis of the sequence of movie photographs, however, shows what appears to be the battleship's foremast in the blast column, with the dark "hole" thought to be the up-ended battleship caused by the mass of the ship blocking the uplifted water column rising above it. Arkansas sank almost immediately; the Navy technical inspection report for Arkansas notes it disappeared within 19 seconds after the blast. According to Bombs at Bikini, "in sinking, she carried with her the dubious honor of being the first battleship to be sunk by an atomic bomb, and the first battleship to be sunk by a bomb that never touched her."
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