NAVYPEDIA

Photo

Indianapolis 1945

Ships

No	Name	Yard No	Builder	Laid down	Launched	Comm	Fate
CA33	Portland	1430	Bethlehem, Quincy	17.2.1930	21.5.1932	23.2.1933	stricken 3.1959
CA35	Indianapolis	399	New York SB, Camden	31.3.1930	7.11.1931	15.11.1932	sunk 29.7.1945

Technical data

Displacement standard, t	10258
Displacement full, t	12755
Length, m	180.4 wl 185.9 oa
Breadth, m	20.1
Draught, m	6.40 full load
No of shafts	4
Machinery	4 sets Parsons geared steam turbines, 8 Yarrow boilers
Power, h. p.	107000
Max speed, kts	32.5
Fuel, t	oil 1417 - 2125
Endurance, nm(kts)	10000 (15)
Armour, mm	belt: 146 - 83, bulkheads: 32 - 25, deck: 64 - 54, barbettes: 38, turrets: 64 - 19, CT: 32
Armament	3 x 3 - 203/55 Mk 9.10.11/13/14, 8 x 1 - 127/25 Mk 10.11.13, 8 х 1 - 12.7/90, 2 catapults, 4 seaplanes (OL, O2U, O3U)
Complement	CA33: 807 CA35: 917 inc flag

Standard scale images

Graphics

Project history

The original project of Portland class cruisers, approved in 1929, represented almost exact copy of Northampton, differing only by on 3m bigger hull length. It was planed to build five ships (CL32-36, subsequently the index was replaced to СА). Already when designt of new cruisers was approved, it was found out, that their prototype, Northampton, was underloaded and it is possible to use a stock of displacement for protection increasing. In this connection it had decided to limit a class by only two ships under the redesigned project, and built other ships on new one (future New Orleans class). Redesigning of the Portland class has turned into increasing of thickness of a deck over machinery and better protection of magazines. These innovations have allowed to ensure more reliable protection of machinery against 152mm shells, and for the first time USN ships had immune zone under 203mm shells, the truth, it concerned magazines only (fore magazines between 60 and 115 cables, and aft ones between 60 and 102 cables). Besides more reliable protection, Portland class differed from predecessors by absence of TTs and doubled number of 127mm AA guns.

Ship protection

Main belt extended to 1.5m below and 3m over waterline. Middle part of the belt abreast machinery was 127mm thick (83mm at lower edge) on 19mm STS plating and end parts abreast magazines were 146mm. Belt was closed by 64mm bulkheads and middle and end parts were separated by 25mm bulkheads. Armoured deck over main belt was 54mm thick over magazines and 64mm over machinery. Barbettes were 38mm thick. Turrets had 64mm faces, 25mm sides, 19mm rears and 51mm crowns.

Modernizations

early 1942, both: - 8 x 1 -12.7/90; + 4 x 4 - 28/75 Mk 1, 12 x 1 - 20/70 Mk 4, SC, Mk 3, Mk 4 radars

5/1943, both: - 4 x 4 - 28/75, 1 catapult, SC radar; + 4 x 4 - 40/56 Mk 1.2, SG, SK radars. Portland can carry 2 seaplanes and Indianapolis 3.

autumn 1944, both: - Mk 3, Mk 4 radars; + Mk 8, Mk 18 radars

1944 - 1945, Portland: + 4 x 2 - 40/56 Mk 1.2, 5 x 1 - 20/70 Mk 4

1944 - 1945, Indianapolis: - 12 x 1 - 20/70; + 2 x 4 - 40/56 Mk 1.2, 8 x 2 - 20/70 Mk 4, full displacement was more than 15000t

1/1946, Portland: 3 x 3 - 203/55 Mk 14, 8 x 1 - 127/25 Mk 19, 4 x 4 - 40/60 Mk 2, 4 x 2 - 40/60 Mk 1, 17 x 1 - 20/70 Mk 10, 1 catapult, 2 seaplanes, SG, SK, Mk 8, Mk 18 radars

Naval service

Indianapolis was badly damaged 30.3.1945 by kamikaze and was under repair till July, 1945; 30.7.1945 she was sunk by three torpedoes from Japanese submarine I58 in Philippine Sea. Portland 13.11.1942 in battle at Guadalcanal received one torpedo hit from Japanese ships, badly damaged and was under repair till May, 1943.