Editing Colorado-class battleship (section)

==Design==
[[File:USS Maryland BB-46 Laid Down.jpg|thumb|upright|left|Hull of ''Maryland'' under construction c. 1917]]

The construction of battleships armed with 16-inch guns was envisioned by the [[General Board of the United States Navy]] and [[Bureau of Construction and Repair]] (C&R) as early as 1913, as the upgrade in gun caliber promised twice the kinetic energy of the [[12-inch/45-caliber Mark 5 gun|12-inch gun]] then in service and half again as much as the [[14-inch/45-caliber gun|14-inch gun]] then being introduced. The 14-inch gun dominated the design of battleships between 1913 and 1916, just as the 12-inch gun had dictated designs from 1908 to 1910. However, while the General Board approved the 16-inch gun as early as 1911, [[George von Lengerke Meyer]], the [[United States Secretary of the Navy|Secretary of the Navy]], felt that a move to the larger gun caliber would make capital ships still on the drawing board obsolete. For this reason, he restricted the [[Bureau of Ordnance]] to proceed no further than blueprints for the new gun as a hedge against foreign developments. He finally approved construction of this gun in October 1912 and the weapon was test-fired successfully in August 1914. This success, along with the unofficial news in several naval publications of 15- and 16-inch weapons being adopted by the [[Royal Navy|United Kingdom]], [[Regia Marina|Italy]], [[Imperial German Navy|Germany]] and [[Imperial Japanese Navy|Japan]], led the Board to consider cancelling the construction of the {{sclass|Pennsylvania|battleship|4}} in favor of an up-gunned design. Such a move meant an increase of 8,000 tons per ship, twice as much as the jump from the {{sclass|Nevada|battleship|5}}s to the ''Pennsylvania''s. Debate continued for the next three years. Each year, President [[Woodrow Wilson]]'s Secretary of the Navy, [[Josephus Daniels]], balked at the potential increase in cost and ordered instead that the design features of the Standard Class be continued, but eventually compromised with the 1917 design battleships by allowing their armament to be upgraded.  However, this was the only substantial change permitted.{{sfn|Friedman|1985|pp=116, 118}}

The design of the ''Colorado'' class was therefore adapted from the preceding {{sclass|Tennessee|battleship|4}}; other than the significant improvement of eight {{convert|16|in|mm|abbr=on|0}}/45 [[Caliber (artillery)|caliber]] guns in four dual [[gun turret|turrets]] taking the place of the ''Tennessee''-class's twelve [[14"/50 caliber gun|{{cvt|14|in|0}}/50 caliber gun]]s in four triple turrets, there was no major difference between the two designs. Likewise, the ''Tennessee''s were the results of modifications to the {{sclass|New Mexico|battleship|4}}, which had been the most modern U.S. Navy capital ships to see service in [[World War I]] and had attracted the attention of British constructors both serving with and outside C&R. This similarity would carry over into the {{sclass|Lexington|battlecruiser|5}} and {{sclass|South Dakota|battleship (1920)|4}}es as the U.S. Navy further standardized its capital ship designs. This was partly the result of wartime experience, when over 250 destroyers and more than 450 submarine chasers had to be built quickly for service in the North Atlantic. The U.S. Navy had done this by a process almost akin to the [[assembly line]], sticking to one basic design per class with a maximum amount of standardization and rationalization. Since the [[Naval Act of 1916]] meant the imminent construction of 16 battleships and six [[battlecruiser]]s, it was necessary to streamline production to save time and labor.{{sfn|Gardiner|Gray|1985|p=118}}{{sfn|Friedman|1985|pp=128, 137}}{{sfn|DiGiulian 2008 (Mark 1)}}{{sfn|Breyer|1974|pp=223, 226}}

Nevertheless, while U.S. battleships were standardized as much as possible, design improvements were incorporated whenever practicable. Most of the changes in the ''Colorado''s were incorporated prior to any of their [[keel]]s being laid. However, plans for the underwater protection—the ships' main defense against [[torpedo]]es and [[shell (projectile)|shells]] that fell short of the ship but traveled through the water to hit underneath the [[waterline]]—could not be worked out in time. The problem was that tests in [[Caisson (engineering)|caissons]]—experiments that would eventually prove that a series of compartments divided between being filled with liquid and being left empty would be a very effective defense against torpedoes—were not yet complete. In order to commence construction of the ships as soon as possible, proposals sent to shipbuilding corporations noted that if they were selected to build the ships, alterations to the design of the ships three months after their keels were laid must be allowed.{{sfn|Friedman|1985|p=134}}{{sfn|Gardiner|Gray|1985|p=117}}

===General characteristics===
[[File:USS Maryland bow view 1944.jpg|thumb|upright|USS ''Maryland'' in March 1944]]

The ''Colorado''s were very similar overall to the ''Tennessee''s, with a {{convert|624|ft|m|adj=on}} [[length overall|overall length]] and a [[beam (nautical)|beam]] at the waterline of {{convert|97|ft|m}}. They displaced {{convert|32600|LT|t}} at normal load and {{convert|33590|LT|MT}} at [[deep load]] and had a [[draft (hull)|draft]] of {{convert|30.5|ft|m|1}}. As in the ''New Mexico'' and ''Tennessee'' classes, they were designed with a [[Bow (watercraft)|clipper bow]] to help keep the ships dryer in heavy seas, and also kept the [[secondary armament]] in the [[superstructure]] rather than in the upper hull (''Pennsylvania'' and earlier classes), where the guns had proved to be excessively wet in heavy seas and thus were frequently unusable.{{sfn|Breyer|1973|p=193}}{{sfn|Friedman|1985|p=134}}

===Propulsion===
[[Turbo-electric transmission]], which had been used in the prior class, was retained here. Advantages included the ability for the turbines to run at optimum speed without regard to propeller speed, which led to greater fuel economy and range, and an easier sub-division of machinery, which increased the ships' ability to withstand torpedo hits. Each of the four propeller shafts was powered by a 5,424 [[kilowatt]] [[electric motor]], fed by two two-phase [[turbo generator]]s ([[General Electric]] for ''Maryland'', [[Westinghouse Electric (1886)|Westinghouse]] for ''Colorado'' and ''West Virginia'') rated at 5,000 [[volt]]s). Eight oil-fired [[Babcock & Wilcox]] [[water-tube boiler]]s, each in its individual compartment, provided steam for the generators. Altogether, the ships' power plant was rated at 28,900 [[Horsepower#Electrical horsepower|electrical horsepower]] (EHP) to provide a [[flank speed]] of {{convert|21|kn|lk=in}}. With a maximum bunker capacity of 4570 tons, the ''Colorado''s{{'}} range without refueling at sea was {{convert|10000|nmi|lk=in}}.{{sfn|Breyer|1973|pp=193, 230}}

===Armament===

====Main guns====
The ''Colorado'' class was armed with eight [[16"/45 caliber gun|{{convert|16|in|adj=on|0}}/45 caliber Mark 1 guns]], which fired a {{convert|2110|lb|kg|adj=on}} armor-piercing (AP) shell at a [[muzzle velocity]] of {{convert|2600|ft/s|m/s|0}} and a rate of about 1.5 rounds per minute to a range of {{convert|34300|yd|m}} at a maximum turret elevation of 30 degrees. Development of this weapon had begun in August 1913, using a bored-out and relined {{convert|13|in|mm|adj=on|0}} Mark 2 gun, with the promise of twice the muzzle energy of the [[12"/50 caliber Mark 7 gun|{{convert|12|in|adj=on|0}}/50 caliber Mark 7 guns]] and 50 percent more than the [[14"/45 caliber gun|14-inch /45 caliber]] weapon used on the ''New York''-class battleships. After an initial proof firing in July 1914 and minor changes, the 16-inch Mark 1 was re-proved in May 1916 and production approved in January 1917. When the ''Colorado''s were modernized in the 1930s, these guns were rebuilt per standard navy practice and redesignated 16-inch/45 (40.6&nbsp;cm) Mark 5 and Mark 8.{{sfn|DiGiulian 2008 (Mark 1)}}

====Secondary guns====
Fourteen [[5"/51 caliber gun|{{convert|5|in|adj=on|0}}/51 caliber]] Mark 15 guns were installed to defend against enemy destroyers. This was reduced to 12 in 1922. The Mark 15 fired a {{convert|50|lb|kg|adj=on}} shell at a velocity of {{convert|3150|ft/s|m/s}} to a maximum range of {{convert|15850|yd|smi km|1|abbr=off|disp=(or)}} at 20&nbsp;degrees{{sfn|DiGiulian 2012 (5"/51)}} at a rate of seven rounds per minute and was extremely accurate, with a danger space longer than the range to the target for distances less than {{convert|3000|yd|m}}. As in the ''New Mexico'' and ''Tennessee'' classes, these were mounted in unarmored casemates on the main deck, one deck higher than in previous classes, to allow them to be manned in heavy weather if necessary.{{sfn|Breyer|1973|p=226}}{{sfn|DiGiulian 2012 (5"/51)}}

Heavily damaged at Pearl Harbor, in 1942 ''West Virginia'' began a major reconstruction that saw her Mark 15 guns removed and replaced with sixteen [[5-inch/38-caliber gun|{{convert|5|in|adj=on|0}}/38 caliber]] Mark 12 dual-purpose guns in twin turrets. Urgently needed in the Pacific, ''Maryland'' and ''Colorado'' retained 8 of the prewar Mark 15s, in Colorado's case until the end of the war;{{sfn|Sturton|2008|p=217}} the twin turrets planned and later installed were at that time in short supply, and it was only in May 1945 that ''Maryland'' would be refitted with 16 5in/38 in 8 twin mountings as in ''West Virginia''. The Mark 12 fired a {{convert|55.18|lb|kg|adj=on}} shell to a maximum range of {{convert|17392|yd|m}} and a maximum elevation of {{convert|37200|ft|m}} at an elevation of 45 degrees.{{sfn|Breyer|1974|p=189}} They had a high rate of fire due to their being hand-loaded but power-rammed and their capability for easy loading at any angle of elevation. The introduction of proximity-fused anti-aircraft shells in 1943 made the 5&nbsp;in/38 even more potent in this capacity.{{sfn|DiGiulian 2012 (5"/38)}}

====Anti-aircraft guns====
[[File:USS West Virginia 1944.jpg|thumb|USS ''West Virginia'' in her final configuration, June 1944. Note 5&nbsp;in/38 twin turrets and number of AA guns]]
Four [[3"/23 caliber gun|{{convert|3|in|adj=on|0}}/23 caliber gun]]s were mounted initially for [[Anti-aircraft warfare|anti-aircraft (AA) defense]]. This was increased to eight guns in 1922. These guns fired a {{convert|3|in|adj=on}} shell at a muzzle velocity of {{convert|1650|ft/s|m/s}} to a maximum range of {{convert|8800|yd|m}} and ceiling of {{convert|18000|ft|m}} at an elevation of 45.3 degrees and a rate of between eight and nine rounds per minute.{{sfn|DiGiulian 2011 (3"/23)}} These weapons were replaced in 1928–1929 with the same number of [[5"/25 caliber gun|{{convert|5|in|adj=on|0}}/25 caliber guns]], the first Navy gun designed specifically for AA use. They fired a {{convert|54|lb|kg|adj=on}} shell at a muzzle velocity of {{convert|2155|ft/s|m/s}} at a rate of between 15 and 20 rounds per minute to a maximum range of {{convert|14500|yd|m}} at an elevation of 45 degrees and a ceiling of {{convert|27400|ft|m}} at a maximum elevation of 85 degrees.{{sfn|DiGiulian 2011 (5"/25)}} These weapons were supplemented with quadruple-mount (quad) [[1.1-inch/75-caliber gun]]s in 1937–1938.{{sfn|Breyer|1973|p=230}}

In 1942, the air defense system on these ships was overhauled completely. In addition to their 5&nbsp;in/25s, they carried sixteen [[Bofors 40 mm Automatic Gun L/60|Bofors 40 mm gun]]s in quad mounts and up to thirty-two [[Oerlikon 20 mm cannon]]s in single mounts. The quad 40&nbsp;mm Bofors fired a {{convert|1.985|lb|kg|adj=on}} shell at a rate of 120 rounds per minute per barrel nominal, 140 to 160 rounds per minute when horizontal (gravity assist), to a maximum range of {{convert|11133|yd|m}} at 45 degrees and a ceiling of {{convert|22299|ft|m}}. The 20&nbsp;mm Oerlikons fired a {{convert|0.271|lb|kg|adj=on}} shell at an average muzzle velocity of {{convert|2725|ft/s|m/s}} and a practical rate of between 250 and 320 rounds per minute to a maximum range of {{convert|4800|yd|m}} at 45 degrees and a ceiling of {{convert|10000|ft|m}}.{{sfn|Breyer|1973|pp=230–232}}{{sfn|DiGiulian 2011 (40mm)}}{{sfn|DiGiulian 2012 (20mm)}}

A second overhaul of AA defense was made between 1944 and 1945, as the Navy had found 20&nbsp;mm shells too light to stop Japanese ''[[kamikaze]]'' planes; this plus the higher approach speeds of these planes made these manually-controlled guns obsolete. In their place, more quad 40&nbsp;mm Bofors mounts were fitted. ''Maryland'' eventually carried 40{{sfn|McDonald|2023|p=210}} 40&nbsp;mm in 10 quad mountings and 36 20mm in 18 twin mountings{{sfn|McDonald|2023|p=210}} (a different source has her with forty-four 40mm in 11 quad mounts and forty-four 20mm in 20 twin and 1 quad mountings.{{sfn|Sturton|2008|p=217}}) ''Colorado'' had either 32{{sfn|Sturton|2008|p=217}} or 40{{sfn|Breyer|1973|pp=230–232}} 40mm in quad mountings but with 39 single, 8 twin and 1 quad 20mm.{{sfn|Sturton|2008|p=217}} ''West Virginia'' carried forty 40&nbsp;mm in quad mountings and 64 20&nbsp;mm guns in 58 single, one twin and one quad mounting{{sfn|Sturton|2008|p=217}}.{{sfn|Breyer|1973|pp=230–232}}{{sfn|DiGiulian 2011 (40mm)}}{{sfn|DiGiulian 2012 (20mm)}}

===Armor and underwater protection===
The "all or nothing" armor scheme introduced in the ''Nevada''-class battleships was continued here, as throughout the Standard-type warships, with armor suite virtually identical to the preceding ''Tennessee'' class. The exception was an increase in belt armor near vital machinery to {{convert|16|in|mm|0}} to correspond with the increased main gun caliber. Otherwise, the minimum thickness along the belt remained 14&nbsp;inches. Upper deck armor was {{convert|3.6|in|mm}} initially and was later increased to {{convert|4.1|in|mm|0}}. Lower deck armor ranged between {{convert|2.25|and|1.5|in|mm}} and was also presumably strengthened during conversion.{{sfn|Breyer|1973|p=230}}

As with the ''Tennessee''s, the ''Colorado''s were modernized in the 1930s to improve their staying power. A new underwater protection scheme featured five compartments separated by armored [[bulkhead (partition)|bulkheads]] {{convert|0.75|in|mm}} thick on either side of the ship: an outer empty one, three filled, and an empty inner one. In addition, the eight [[boiler]]s were moved from their location in previous designs and placed in separate spaces to port and starboard of the [[turboelectric]] power plant. This arrangement formed another line of defense, which would allow the ship to sail if one or even an entire side of boilers was incapacitated. A consequence was the chief aesthetic change between the ''New Mexico''s and ''Tennessee''s: the single large [[wikt:funnel#Noun|funnel]] of the former was replaced by two smaller funnels in the latter.{{sfn|Gardiner|Gray|1985|p=117}}{{sfn|Friedman|1985|pp=134, 137, 225}} Turret armor was 5" on the roofs, 8 on the sides and rears, and 18 on the faces.<ref>{{Cite book|title=American Battleships, Carriers, and Cruisers|last=Lenton|first=Henry|publisher=Doubleday & Company INC.|year=1968|location=Garden City, NY|pages=29|lccn=68-14047}}</ref>

Other improvements imported from the ''Tennessee'' class included an attempt to move the forward torpedo room away from the 16-inch gun [[magazine (artillery)|magazines]], as the room was viewed as vulnerable. Also, the design called for the use of external, rather than internal, [[belt armor]] so that a "break in the continuity of the side structure" would not exist, which would minimize drag in the water and any corresponding waste of power.{{sfn|Gardiner|Gray|1985|p=117}}{{sfn|Friedman|1985|pp=134, 137}}