The Portland class: Last of the “classics”
Designed after the Northampton, the two heavy cruisers Portland and Indianapolis were contemporary of the New Orleans class, but improved on many points and mainly that of protection.
Spacious, bigger and heavier than the Northamptons, they were also the last of the “tin clad” cruisers… Their tonnage was already 10,260 tonnes standard, so there was no additional armor margin possible within the Washington treaty limitations.
USS Indianapolis at Pearl Harbor circa 1937
Some areas were protected against 6 in (152 mm) shells at certain angles, but 8 in (203 mm) shells could pass through them without encountering obstacles. From their initial design, the torpedo tubes were removed, and the AA increased in compensation. Among their originality, the front mast was much lower, as well as the rear one, lighter and cleared of spotlights, relegated on footbridges behind the funnel, in order to improve stability. Roomy, they served also as command ships.
USS Portland in drydock at Cockatoo Island Dockyard late 1942
Career of the Portlands
In May 1943, these two ships were taken over for a complete rebuilding, among other things to clear the bow for the AA, more than doubled. The superstructure was rebuilt, lightened and lowered, with an open deck, and the tripod mast was removed in favor of a lattice structure in front of the rear funnel. The AA went up to 4 quadruple and 4 doubles 40 mm Bofors and 12 singles 20 mm Oerlikon guns. The two ships were heavily engaged in the Pacific. These modifications were the prototypes of the subsequent Northampton redesigns.
USS Portland at Mare Island Naval Shipyard 30 July 1944
The Portland (CA33), was very active and deployed during most major naval operations of the Pacific, and several times damaged. She survived the war and was broken up in December 1959. In 1945, USS Indianapolis became (in)famous. First for delivering the Bomb A (“Little Boy”) at Tinian base, where a B29 named Enola Gay sewn apocalypse over Hiroshima. As a kind of stroke of fate (and vengeance for the people of Hiroshima), the cruiser on her return on July 29 was torpedoed by a Japanese submarine. She sank quickly, taking a large part of her crew, while survivors were left stranded in the burning oil, dyring of exhaustion and fatigue, and famously unrelentless shark attacks for several days before being saved. This was the last ship of the US Navy and last of the allies to be sunk during the Second World War.
Displacement: 10 258 t. standard -12 755 t. Fuly loaded
Dimensions: 185,9 m long, 20,12 m wide, 6,40 m draft
Machines: 4 shafts turbines Parsons, 8 Yarrow boilers, 107 000 hp.
Top speed: 32,5 knots
Armor: belt 57, turrets 65, decks 160-50
Armament: 9 x 8 in (203mm) (3×3), 8 x 5in (127mm), 8 x .5 cal. (12,7 mm) M2HB AA, 4 seaplanes
USS Portland in 1945, the horizontal livery in effect since the end of 1944: Light gray/medium gray/dark blue – Illustration by the author
Conways all the world’s fighting ships 1922-1947