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fighting ships of the world

UNITED STATES NAVY (UNITED STATES OF AMERICA)

CRUISERS

NEW ORLEANS heavy cruisers (1934-1937)

San Francisco 1942

San Francisco 1945

Project history: Beginning designing of successor of Portland class by 1929 program (CA37-41), USN staff decided that protection of first heavy cruisers is insufficient. After a long discussion General Board refused the plans of modified Northampton class in favour of more protected ship. Her creation was 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 unchanged, but hull was quite new and was notably shorter and narrower in comparison with predecessors. Length reduction was 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 203mm shells. The protection weight made 15% of standard displacement. As result the immune zone under fire of 203mm guns at a relative 60° bearing laid in a band between 60 and 120 cables.

Originally it was planed to build 5 ships (CA37-41) under this design, 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 FY1929 programme. They were followed by three ships of the FY1930 programme (СА37-39), a little differing from the former three. СА37 and СА38 had more protected barbettes and new lighter 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 FY1931 programme and completely repeated design of СА39.

By the middle of war the stability came nearer to a dangerous limit, and further modernizations were accompanied by additional lead ballast. Besides, ships lost CTs and have rebuilt bridges.

Ship protection (CA32, 34, 36): 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 the machinery (on 2nd deck level) and magazines (on 1st platform level). Its thickness decreased to 32mm fwd from fore magazines. Barbettes were 127mm thick. Turrets had 203mm faces, 95-38mm sides, 38mm rears and 70mm crowns.

Ship protection (CA37, 38): 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 the machinery (on 2nd deck level) and magazines (on 1st platform level). Its thickness decreased to 32mm fwd from fore magazines. Barbettes were 152mm thick. Turrets had 203mm faces, 95-38mm sides, 38mm rears and 70mm crowns.

Ship protection (CA39, 44): 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 the machinery (on 2nd deck level) and magazines (on 1st platform level). Its thickness decreased to 32mm fwd from fore magazines. Barbettes were 133mm 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 Mk 4, SC, Mk 3 radars

late 1942, all survived: + (6 - 10) x 1 - 20/70 Mk 4

late 1943, all survived: - 4 x 4 - 28/75, 1 catapult, SC radar; + 6 x 4 - 40/56 Mk 1.2, 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 Mk 4

1944 - 1945, Minneapolis: - (12 - 16) x 1 - 20/70; + 8 x 2 - 20/70 Mk 4

1944 - 1945, Tuscaloosa: - (12 - 16) x 1 - 20/70; + 28 x 1 - 20/70 Mk 4

1944 - 1945, San Francisco: - (12 - 16) x 1 - 20/70; + 26 x 1 - 20/70 Mk 4

1/1946, New Orleans: 3 x 3 - 203/55 Mk 14, 8 x 1 - 127/25 Mk 19, 6 x 4 - 40/60 Mk 2, 14 x 2 - 20/70 Mk 24, 1 catapult, 4 seaplanes, 2x SG, SK, Mk 3, Mk 4 radars

1/1946, Minneapolis: 3 x 3 - 203/55 Mk 15, 8 x 1 - 127/25 Mk 19, 6 x 4 - 40/60 Mk 2, 8 x 2 - 20/70 Mk 24, 1 catapult, 4 seaplanes, 2x SG, SK, SP, Mk 3, Mk 4 radars

1/1946, Tuscaloosa: 3 x 3 - 203/55 Mk 12, 8 x 1 - 127/25 Mk 19, 6 x 4 - 40/60 Mk 2, 28 x 1 - 20/70 Mk 10, 1 catapult, 4 seaplanes, 2x SG, SK, Mk 3, Mk 4 radars

1/1946, San Francisco: 3 x 3 - 203/55 Mk 12, 8 x 1 - 127/25 Mk 19, 6 x 4 - 40/60 Mk 2, 26 x 1 - 20/70 Mk 10, 1 catapult, 4 seaplanes, 2x SG, SK, Mk 3, Mk 4 radars

Naval service: Vincennes, Quincy and Astoria were sunk by gunfire and torpedoes of Japanese heavy cruisers 9.8.1942 in battle at Sawo Island (Guadalcanal). New Orleans 30.11.1942 was badly damaged by Japanese torpedo (fore end was torn off to a No2 turret) and returned to service in July, 1943. Minneapolis was damaged 30.11.1942 by two torpedoes from Japanese destroyers. Fore end to a No1 turret was cut off, repair lasted till September, 1943. San Francisco 13.11.1942 was badly damaged by gunfire of Japanese ships (up to 45 shell hits) and was under repair till February, 1943.

Minneapolis 1941

© Ivan Gogin, 2014