UNITED STATES NAVY (UNITED STATES OF AMERICA)

Ship project history: At beginning to work on the project of cruisers which should follow Portland class by 1929 program (CA37-41), in American naval staff the judgement about insufficient protection of the first heavy cruisers was more and more spread. After a long discussions General Board have refused from plans of the further development of Northampton class in favour of the ship with the strengthened protection. Her creation was represented possible thanking to that circumstance, that Northampton class cruisers had standard displacement approximately on 1000t less than limit, appointed by the Washington conference, and this reserve could be expend on protection strengthening.

Structure (but not an arrangement!) of machinery of new cruisers remained without changes, but hull has been projected anew and was notably shorter and narrower in comparison with predecessors. Length reduction has been reached at the expense of abandoning from machinery arrangements in en echelon in favour of the linear. Have besides, lengths of everyone machinery room was decreased. It allowed to shrink a length of waterline belt and increase its thickness to 127mm. Differing from predecessors, turrets received protection against fire of 203mm guns. The protection weight made 15% of standard displacement. As result the immune zone under fire of 203mm guns at a relative bearing 60° laid in a band between 60 and 120 cables.

Originally it was planed to build under new project 5 ships (CA37-41), however they so exceed Northampton class (CA32-36), that it has been solved to build CA32, 34 and 36, the order on which was received by Naval Yards, under the changed project (simultaneously building of CA39-41 was suspended).

First three cruisers of New Orleans class (CA32, 34 and 36) were built under the program of FY1929. They were followed by three ships of the 1930 program (СА37-39), a little differing from leading three. СА37 and СА-38 had more protected barbettes and new more light 203mm guns in more compact turrets. On СА39 it have provided possibility of fitting in the future of 28mm AA MGs that has demanded setting off of a reserve of displacement. For this purpose it was necessary to decrease a thickness of barbettes. Last ship of a class, СА44 was built under the 1931 program and completely repeated СА39.

By the middle of war the stability has come nearer to a dangerous limit, and the further updates were accompanied by the additive ballast. Besides, ships have lost CTs and have rebuilt bridges.

Ship protection: Main belt abreast machinery extended to 1.5m below and 2.86m over waterline. It was 127mm thick (76mm at lower edge) on 19mm STS plating. There were narrow belts abreast magazines. Thickness of these belts was 102mm decreasing to 76mm at lower edge. Magazines were protected by 37mm bulkheads fore and aft, machinery and magazines were separated by 76-51mm bulkheads. Armoured deck over main belt was 57mm over machinery (on 2nd deck level) and magazines (on 1st platform level). Its thickness decreased to 32mm fwd from fore magazines. Barbettes were 127 (CA32, 34, 36) / 152 (CA37, 38) / 133mm (CA39, 44) thick. Turrets had 203mm faces, 95-38mm sides, 38mm rears and 70mm crowns.

Modernizations: Astoria, 6/1941; New Orleans, Minneapolis, 11/1941; Tuscaloosa, San Francisco, Quincy, Vincennes 12/1941 - 4/1942: + 4 x 4 - 28/75 Mk 1

mid-1942, all: - 8 x 1 - 12.7/90; + 6 x 1 - 20/70 Oerlikon, SC, Mk 3 radars

late 1942, all survived: + (6 - 10) x 1 - 20/70 Oerlikon

late 1943, all survived: - 4 x 4 - 28/75, 1 catapult, SC radar; + 6 x 4 - 40/56 Bofors, 2x SG, SK, Mk 4 radars. CT was removed.

Minneapolis, 1944: - 3 x 3 - 203/55; + 3 x 3 - 203/55 Mk 12/15, SP radar

1944 - 1945, New Orleans: - (12 - 16) x 1 - 20/70; + 14 x 2 - 20/70 Oerlikon

1944 - 1945, Minneapolis: - (12 - 16) x 1 - 20/70; + 8 x 2 - 20/70 Oerlikon

1944 - 1945, Tuscaloosa: - (12 - 16) x 1 - 20/70; + 28 x 1 - 20/70 Oerlikon

1944 - 1945, San Francisco: - (12 - 16) x 1 - 20/70; + 26 x 1 - 20/70 Oerlikon