Atlanta

History

Design

The Atlanta-class light cruisers were born out of a requirement by the US Navy for a class of scout cruisers that could also be destroyer flotilla leaders. As such, the 8,000 ton displacement limitation by the 1936 London Naval Treaty seemed ideal; what was needed was a small, fast ship armed with light-caliber weapons to fend off enemy destroyers. Although the final configuration was indeed capable of this intended role, by the onset of the Second World War in the Pacific, Atlanta-class cruisers took on a more prominent duty: that of anti-aircraft escorts, as they had the perfect set of tools for the job.

Originally it was proposed to arm the class with a combination of 6-inch and 5-inch rifles, but designers quickly realized that a mixed battery loadout was not ideal for such a small hull. With the development of the intended 6-inch mounts delayed, it was decided to use the readily available 5-inch/38 rifles. Final plans for Atlanta mounted sixteen (16) of them, in eight (8) twin barreled, dual-purpose turrets: three forward, three aft, and two in "waist" positions, all controlled by two Mark 37 directors with Mark 4 "FD" fire control radar. In conjunction with the new “Variable Time” proximity fuse shells, the lethality of the main armament in anti-aircraft warfare soon became apparent. Supplementary to this newfound primary role, by 1942 the original AA armament of 1.1-inch guns and .50 caliber machine guns were replaced by the more reliable Oerlikon 20mm — and later, the Bofors 40mm — auto-cannons as they came available. USS Atlanta herself, however, was never fitted with the 40mm guns.

Designed as scouts, Atlanta-class ships were outfitted with 585 tons of armor at the heaviest. This was distributed as 3.5 inches (89 mm) of belt and bulkhead armor, 1.25 inches (32 mm) of deck and turret armor, and 2.5 inches (63 mm) of armor on the conning tower. The designers initially proposed for a top speed of above 40 knots, but considering the weight of armor and artillery, the design speed was decreased to a more realistic 33 knots. Atlantas were also fitted with four high-pressure boilers linked to two geared turbines that produced a total of 75,000 shaft horsepower. This gave the class good sea legs, producing adequate speeds and decent range.

Unique to the Atlanta-class — amongst American cruisers, anyway — was their array of antisubmarine equipment. They carried hull-mounted sonar in conjunction with two depth charge racks and six throwers, giving them the ability to confront enemy submarines. In practice, though, the cruisers were not agile enough to effectively combat submarines. Another novelty uncommon on US Navy cruisers of the era: they were equipped with torpedoes, mounting two quadruple-tube launchers just forward of the waist turrets.

The class underwent modifications throughout World War II. Unsurprisingly, the number of AA mounts increased; by the late war era, the waist turrets were removed in favor of more 40mm Bofors guns. In order to mitigate the increased weight, gear deemed unnecessary — such as the ASW equipment and torpedoes — were removed completely. The old electronic suite of radars and directors were replaced by more modern variants. One relatively unique alteration was the redesign of the closed-roofed bridges to an open-top version; the previous design inhibited efficient command of the AA guns against air attack.

USS Atlanta (CL-51) was the lead ship of her class, built by Federal Shipbuilding and Dry Docks Co. in Kearny, New Jersey. Laid down in 22 April 1940, she was launched 6 September 1941.

Historical Inaccuracies

• Atlanta's historical Measure 12 (modified) camouflage scheme is missing. Her hull was painted solid Navy Blue, while her upperworks wore the mottled pattern of Ocean Gray and Haze Gray. She was sunk while wearing this scheme.
• Premium camouflage resembles the Measure 32/22D scheme, which was applied to surviving Atlanta-class cruisers in 1944; Atlanta was sunk in November 1942.

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  USS Atlanta (CL-51).