The Colorado class battleships (or Maryland class, for those who prefer to name ship classes after the first unit to be completed) were up-gunned versions of the preceding Tennessee class, sharing their general design and appearance, but replacing the earlier ships' twelve 14-inch/50-caliber guns with eight 16-inch/45s. Built with Fiscal Year 1917 appropriations and delayed by higher priorities during World War I, two of the Colorados were the last new U.S. battleships to enter service for nearly two decades. The fourth of the class, Washington, was the only new U.S. ship cancelled under the Washington Naval Treaty for the Limitation of Naval Armaments that had actually been launched. Their 32,600-ton standard displacement was slightly heavier than that of the Tennessee class, and the power and accuracy of their sixteen-inch guns represented a notable improvement. The multi-layered anti-torpedo side protection system, armor, turbo-electric drive, and improved fire controls of the Tennessees were repeated in the Colorado, which were typical U.S. battleships of the day: robust, heavily-armed and armored but relatively slow. During the 1920s and 1930s, the five ships of these two classes were popularly known as the Battle Fleet's "Big Five."

During the early 1930s, it was intended to modernize the "Big Five," but the only work actually done produced a modest increase in anti-aircraft guns and the associated fire control systems. Two of the Colorado class, Maryland and West Virginia were present at the attack on Pearl Harbor. The latter was sunk, her side protection system overwhelmed by a mass of Japanese torpedoes. Colorado was then completing an overhaul that added additional depth to the side protection, increasing her beam to 32.9 meters (108 feet), and Maryland soon received similar improvements. Both ships were further altered later in 1942, with their "cage" mainmasts cut down and anti-aircraft guns increased in numbers. Later, they received new after superstructures to carry better gun directors. Following kamikaze damage in late 1944, Maryland was fitted with a sixteen-gun five-inch/38 dual-purpose secondary battery, replacing the previous mixed lot of low-angle five-inch/51s and high-angle five-inch/25s. Colorado finished her days with the mixed second battery.

The massively damaged West Virginia was salvaged in 1942 and 1943, and received the same extensive modernization applied to the two Tennessees: hull widened to 34.7 meters (114 feet), greatly improved fire controls and anti-aircraft batteries, a secondary battery of sixteen five-inch/38-caliber guns in twin mounts, and a generally "modern" appearance.

These ships saw the usual wartime employment of older battleships, serving as a "fleet in being" in 1942 and 1943 and thereafter providing big-gun bombardment in support of amphibious operations. Maryland and West Virginia were present for the last fight between opposing battleships, the Battle of Surigao Strait on 25 October 1944. Laid up after the War, the three Colorado class ships were part of the Reserve Fleet until 1959, when they were sold for scrapping.

The Colorado class was part of the "Standard type battleship" concept of the US Navy, a design concept which gave the US Navy a homogenous line of battle (very important, as it allowed the Navy to plan maneuvers for the whole line of battle rather than detaching "fast wing"s and "slow wing"s). The "Standard" concept included long-range gunnery, moderate speed (21 knots), a tight tactical radius (~700 yards) and improved damage control. The other Standards were the Nevada, Pennsylvania, New Mexico and Tennessee classes.

General Characteristics

• Displacement: 32,600 tons (standard)
• Length: 190.2 meters (624 feet)
• Beam: 29.7 meters (97 feet 4 inches)
• Powerplant: 28,900 horsepower steam turbines with electric drive
• Speed: 21 knots
• Armament
  • Main Battery): Eight 16-inch/45-caliber guns in four twin turrets
  • Secondary Battery-as built): Twelve or fourteen five-inch/51-caliber guns in single casemate mountings (six or seven guns on each side of the ship). Later in the 1920s, eight five-inch/25 anti-aircraft guns were added.

External links

Naval Historical Center (http://www.history.navy.mil/photos/usnshtp/bb/bb45cl.htm)