Portland-class cruiser

USS Indianapolis (CA-35) off the Mare Island Naval Shipyard on 10 July 1945
Class overview
Name	Portland class
Builders	Bethlehem Fore River, MA New York Shipbuilding, NJ
Operators	United States Navy
Preceded by	Northampton class
Succeeded by	New Orleans class
Planned	5
Completed	2
Lost	1
Retired	1
Preserved	0
General characteristics
Type	Heavy cruiser
Displacement	9,950–9,800 long tons (10,110–9,960 t)
Length	592 ft (180 m) wl 610 ft 3 in (186.00 m) oa
Beam	66 ft 3 in (20.19 m)
Draft	21 ft (6.4 m) (mean); 23 ft (7.0 m) (maximum)
Propulsion	4 × Parsons geared turbines, 8 × White-Forster boilers, 4 × shafts, 107,000 ihp (79,800 kW)
Speed	32.7 kn (37.6 mph; 60.6 km/h)
Range	13,000 nmi (14,960 mi; 24,080 km) at 15 kn (17 mph; 28 km/h)
Capacity	Fuel oil: 1,500 tons
Complement	807 (peacetime)
Armament	(1945) 9 × 8 in (203 mm)/55 cal guns (3x3) 8 × 5 in (127 mm)/25 cal AA guns 24 × 40 mm AA guns (4x4 + 4x2 Portland, 6x4 Indianapolis) 12 × 20 mm AA cannons
Armor	Belt 3.25–5 in (83–127 mm) Deck 2.5 in (64 mm) Barbettes 1.5 in (38 mm) Gunhouses 1.5–2.5 in (38–64 mm) Conning tower: 1+1⁄4 in (32 mm)
Aircraft carried	3 × SOC Seagull scout-observation seaplanes
Aviation facilities	2 × catapults

The Portland class of heavy cruisers was a class of ships designed and constructed by the United States Navy in 1930. The two ships of the class, Portland and Indianapolis, saw extensive service during the Pacific War in World War II.

Designed as a modification over the previous Northampton-class cruiser, the Portland class displaced just under 10,000 long tons (10,000 t) and featured heavier armor and armament than previous cruisers. Featuring 8"/55 caliber guns and designed to function as fleet flagships, the Portland class were intended to fix problems with armament and armor that had been a weakness of preceding U.S. cruisers. These designs were carried over to the following New Orleans class, to which six intended Portland cruisers were converted, three of which were already mid-construction.

Portland served in many engagements including the Battle of Coral Sea, the Battle of Midway and the Guadalcanal Campaign, where she was severely damaged but nonetheless able to return to service. She later fought in the Battle of Leyte Gulf and the Battle of Okinawa. Indianapolis served as a fleet flagship for much of the war and fought in the Battle of Philippine Sea and the Battle of Iwo Jima. On 30 July 1945, after transporting components for the nuclear weapons Little Boy and Fat Man from the United States, she was torpedoed by the Japanese submarine I-58. Due to a series of errors and miscommunications her loss was not discovered for several days, and only 316 of her 1,195 crew survived – the greatest single loss of life at sea, from a single ship, in the history of the U.S. Navy.