Editing Colorado-class battleship (section)

==Modifications==
[[File:Colorado illustration.png|thumb|Illustration of the ''Colorado''-class design, created in 1917]]
With [[fiscal year]] 1917 appropriations, bids on the four ''Colorado''s were opened on 18 October 1916; though ''Maryland''{{'}}s keel was laid on 24 April 1917, the other three battleships were not until 1919–1920. With the cancellation of the first {{sclass|South Dakota|battleship (1920)|4}}, the ''Colorado''s were the last U.S. battleships to enter service for nearly two decades. They were also the final U.S. battleships to use twin gun turrets—the {{sclass|North Carolina|battleship|5}}s and second ''South Dakota'' classes had nine [[16"/45 caliber Mark 6 gun|16-inch/45 caliber]] guns and the {{sclass|Iowa|battleship|5}}s used nine [[16"/50 caliber Mark 7 gun|16&nbsp;in/50 caliber]]{{sfn|Gardiner|Gray|1985|p=118}}{{sfn|Friedman|1985|pp=137, 420–421}}{{sfn|Gardiner|Chesneau|1980|pp=97–100}} in three triple turrets.

===Inter-war modernization===
Plans for modernization of the ''Tennessee'' and ''Colorado'' classes were made in October 1931, in part to take advantage of loopholes in the [[Washington Naval Treaty]]. While reconstruction under this treaty was allowed only to increase protection from air and underwater attack, it could include improvements in fire control and increased elevation for main armament as these items were not listed in the treaty. Also, any changes made inside the hull could be justified as meant to increase protection, even if the outcome meant increased speed or longer operational range, since the term "blister" had been specified to limit changes only outside the hull, such as main armor belt thickness and main gun caliber. Modifications to the secondary battery were also outside the purview of the Washington Treaty.{{sfn|Friedman|1985|p=189}}

Included in initial plans was some protection against [[Shell (projectile)#Chemical|chemical shells]] which contained poisonous gas,<!--p203--> although the General Board stated in the late 1920s that decontaminating a battleship hit with these shells would not be possible—the ship would have to be [[Scuttling|scuttled]].<!--p139--> Also, the deck armor was to be bolstered with {{convert|80|lb|kg|abbr=on}}-[[special treatment steel]] (STS)—which would add {{convert|1319|LT|t ST|abbr=on}} to the displacement of the ships—the armor on the tops of the main turrets was to be made thicker, [[fire control system|fire controls]] were to be improved with the latest technology, and new shells for the main guns were to be designed.<!--p203--> Two (later four) quad 1.1-inch guns were to be added, and all of the machinery in place would be removed in favor of newer equipment so that the ships would not lose any speed with the great increase in weight.<!--p203--> [[Anti-torpedo bulge]]s were also to be installed to improve buoyancy but not to increase the ships' beams any greater than {{convert|106|ft|m}} so they could still use the [[Panama Canal]] when transferring from the Atlantic to the Pacific and vice verse.<!--p203--> These improvements were estimated to cost about [[U.S. dollar|$]]15,000,000 per ship ($71,723,000&nbsp;total). However, with the country in the throes of the [[Great Depression]], not much money was available for the Navy. Savings of $26,625,000 could be realized by reconditioning the propulsion machinery rather than replacing it, which would lower the ships' speed. Adding protection against chemical shells could be dropped, along with development of the new shells. Nevertheless, the cost-saving elements of the later proposal were later dropped. The Navy asked the [[Secretary of the Navy]] to request money in the fiscal year 1933 to modernize the two classes from [[Congress of the United States|Congress]], but the depression worsened. Although proposals for modifications were still made, plans were put on hold and never carried out.{{sfn|Friedman|1985|pp=139, 203}}

[[File:USS West Virginia Oct 1935.jpg|thumb|left|''West Virginia'' in October 1935 off Hawaii]]

In the beginning of 1934, the Bureau of Construction and Repair proposed that the "Big Five"—the two ''Tennessee''s and three ''Colorado''s—be fitted with anti-torpedo bulges so that the ships could benefit from increased [[buoyancy]]; because of, among other factors, the normal procedure of leaving port with the maximum amount of fuel possible on board, the five ships were quite overweight and rode low in the water. For example, in June 1935, ''Tennessee'' had a normal operating [[Displacement (ship)|displacement]] of {{convert|38200|LT|t ST|abbr=on}}—more than {{convert|2000|LT|t ST|abbr=on|0}} above the maximum emergency load her original design called for. This made her draft higher—meaning that the ship's waterline was down {{convert|5|ft|4|in|mm|abbr=on}}. Construction and Repair called for a bulge on the ''Colorado''s that would displace about {{convert|2000|LT|t ST|abbr=on|0}} and raise the ships' draft by {{convert|20|in|mm|abbr=on}}. Installing these would be a year's worth of work, with each ship spending six months of that in a [[dry dock]]—the first month docked so that the hull shape could be determined, the next six sailing while the bulge was built, and the last five back in the dock so it could be added to the ship.{{sfn|Friedman|1985|p=207}}

Three years later (1937), the various [[United States Navy bureau system|Navy bureaus]] held a joint meeting to discuss a possible partial modernization of the ''Tennessee''s and ''Colorado''s. They were much different than the changes proposed in 1933; there were no provisions for extra deck armor, but many additions and replacements. To gain space for newer fire control systems, the ships were to be reboilered. The main and secondary battery fire controls were to be replaced, including new rangefinders and plotting room instruments for the main, while new [[Ship Gun Fire Control Systems#MK 33 Gun Fire Control System (GFCS)|Mark 33]] anti-aircraft fire control directors were planned. The mainmast and [[M2 Browning]]s would be removed, and studies of the feasibility of a torpedo bulge, the addition of which Construction and Repair believed to be paramount, which would increase the beam to {{convert|108|ft|m|abbr=on}} and displacement to {{convert|39600|LT|t ST|abbr=on}}. Varying plans for these were complete by October 1938. None was a full reconstruction; costs ranged from $8,094,000 to $38,369,000 per ship. However, as the money for the improvements would lessen the amount available for new battleship construction, and these would be better than any reconstructed old battleship, the Secretary of the Navy rejected these plans in November. Congress did appropriate $6,600,000 in 1939 for some of these improvements, including the bulges.{{sfn|Friedman|1985|p=207}}

===World War II changes===
With the beginning of World War II in Europe, the Navy began to apply lessons learned by the British to U.S. ships.<!--p207--> The Board under [[Ernest J. King]] of 1940–1941 proposed sweeping changes to the secondary armament of the battleships to increase their defense against air attacks. These included the removal of all 5&nbsp;in/25 caliber guns and 5&nbsp;in/51 in favor of the [[dual purpose gun|dual-purpose]] 5&nbsp;in/38, the addition of six quad 1.1-inch guns, and the cutting away of superstructure to clear arcs of fire for the new [[anti-aircraft]] weapons. An ultimate secondary battery of sixteen 5 in/38 in dual mounts, sixteen Bofors 40&nbsp;mm in quadruple mounts and eight single Oerlikon 20&nbsp;mm guns was called for by the board in 1941, although they were not certain the ships could handle the added weight and it would take a large amount of time in dry dock for these modifications to take place. With these concerns, an interim measure of four quad 1.1-inch guns was proposed by the board; however, the gun was not being produced in any great number very quickly, so a second interim solution was implemented. [[3"/50 caliber gun|{{convert|3|in|mm|abbr=on}}/50 caliber guns]] were added to all of the U.S. battleships except for ''Arizona'' and ''Nevada'' by June 1941; these were replaced on the three battleships in the Atlantic by the quad 1.1-inch guns by November—they received them first because they were closer to a war zone.{{sfn|Friedman|1985|pp=207, 353}}

As these modifications were carried out upon the various battleships, much additional weight was added onto the already overweight ships, forcing torpedo bulges to be added so that a decent [[Freeboard (nautical)|freeboard]] could be maintained. These would cost $750,000 and around three or four months in a dry dock. The King Board suggested that the deck armor be bolstered and 5&nbsp;in/38 dual-purpose guns be added, but the [[Chief of Naval Operations]] decreed that any major changes such as these had to wait due to the wars raging around the world at the time. The addition of bulges, however, was approved for the "Big Five", with each ship spending three months in dry dock at the [[Puget Sound Naval Shipyard]]. ''Maryland'' would be first (17 February 1941 to 20 May), followed by ''West Virginia'' (10 May to 8 August), ''Colorado'' (28 July to 28 October), ''Tennessee'' (19 January 1942 to 21 April) and ''California'' (16 March to 16 June).{{efn|name=refits}} However, the estimates for how long the addition of bulges would take were too low; Puget Sound believed that they could complete work on ''Maryland'' in 123 calendar days (about four months)—if the work would be given a priority equal to that of {{USS|Saratoga|CV-3|2}}{{'}}s refit and higher than new construction.{{sfn|Friedman|1985|p=207}}

Only two of the ships had bulges added to them through this program, ''Maryland'' (completed 1 August 1941) and ''Colorado'' (26 February 1942); the attack on Pearl Harbor interrupted the refits intended for ''West Virginia'' and the two ''Tennessee''s. The surprise strike did not touch ''Colorado'', which was at Puget Sound, and did not hurt ''Maryland'' very badly; however, ''West Virginia'' was severely damaged and needed a major refit at minimum.{{sfn|Friedman|1985|pp=207, 345}}

[[File:USS Maryland 9 Feb 1942.jpg|thumb|''Maryland'' on 9 February 1942, little changed from her pre-war configuration]]

Little to no major modifications were made to the two active ''Colorado''s in the opening months of the U.S.'s entry into the war; all of the battleships in the Pacific Fleet had a constant order to be ready to sail within 48 hours in case of a Japanese attempt to invade Hawaii or the West Coast and could not be spared for any major yard work. ''Colorado'' was hurried through the rest of her refit with the addition of essential items like [[radar]], splinter protection, fourteen Oerlikon 20&nbsp;mm and four quad 1.1-in guns; ''Maryland'' received a similar treatment later, the only difference being sixteen 20&nbsp;mm guns and no 1.1-in guns. Although tower masts were constructed for ''Colorado'' and ''Maryland'' and a majority of their aft [[cage mast]]s were cut down by the ships' crews in the beginning of 1942, the ships could not be spared the time needed to install the new masts. The tower masts were placed into storage and not used until early 1944.{{sfn|Friedman|1985|p=356}}

''Colorado'' and ''Maryland'' were greatly needed in the war zone, and as such did not undergo a major refit until 1944, although minor additions and removals, mainly to the anti-aircraft weaponry, were made in-between. Throughout the war, both ships saw their anti-aircraft battery changed constantly. Beginning in 1942, they carried eight 5&nbsp;in/25, four quad 1.1-in guns, a greatly varying number of 20&nbsp;mm guns, and eight .50 caliber machine guns. In June 1942, ''Colorado'' had fourteen 20&nbsp;mm guns; just five months later, this was upped to twenty-two, with thirty-six temporarily approved for a later time. By February 1943, both ''Colorado'' and ''Maryland'' had two more quad 1.1-in guns added (for a total of six mounts) and forty-eight total 20&nbsp;mm guns; a month later she was given an additional ten .50 caliber machine guns. November 1943 saw the removal of two of the single-purpose 5&nbsp;in/51, the six quad 1.1-in guns, and a small number of 20&nbsp;mm guns (six on ''Colorado'' and eight on ''Maryland'') in favor of thirty-two Bofors 40&nbsp;mm guns – six quad and two twin.{{sfn|Friedman|1985|p=364}}

Both ships finally underwent major refits in 1944. Here their remaining aft cage masts were taken off in favor of the tower masts, the two twin 40&nbsp;mm replaced by quads, a quadruple 20&nbsp;mm added, and a new radar fitted. Although more extensive refits were proposed by Admiral [[Ernest King|Ernest J. King]], including the addition of eight twin 5&nbsp;in/38, more advanced fire control systems, and a second protective deck plating, the [[Bureau of Ships]], after demonstrating what would have to be removed as compensation for the weight added for King's ideas, counter-proposed that a smaller reconstruction, like the ones given to the ''New Mexico'' class, would be more desirable. However, no action was taken until ''Maryland'' was struck by a kamikaze aircraft. While undergoing repair, eight twin 5&nbsp;in/38 were added, but nothing else; her [[conning tower]] was removed and replaced by a {{convert|50|lb|kg|abbr=on}} special-treated steel structure to balance the additional weight of the 5&nbsp;in guns.{{sfn|Friedman|1985|pp=364, 368}}