USS Detroit (CL-8) was an light cruiser, originally classified as a scout cruiser, of the United States Navy. She was the fourth Navy ship named for the city of Detroit, Michigan. She spent her first eight years as part of the Scouting Fleet either in the Atlantic or Mediterranean. Her first duty was to assist in the USAAS's first aerial circumnavigation of the world in 1924 and transported the United States Secretary of State Frank B. Kellogg, in 1927, from Ireland to France for the negotiations that led to the signing of the Kellogg-Briand Pact. In 1931 she joined the Battle Force, where her home port was San Diego until moving to Pearl Harbor in 1941. Detroit was moored next to her sister when the Japanese attacked on the morning of 7 December 1941.
Built in Quincy, Massachusetts
Detroit ordered 4 March 1917 with the contract being awarded to Bethlehem Shipbuilding Corporation's Fore River Shipyard in Quincy, Massachusetts, on 21 August 1917. She was laid down on 10 November 1920 and launched 29 June 1922. Her sponsor was Miss M. Couzens, daughter of James J. Couzens, the Mayor of Detroit, Michigan. Detroit was commissioned on 31 July 1923, with Captain J. Halligan, Jr. in command.
Detroit was long at the waterline with an overall length of , her beam was and a mean draft of . Her standard displacement was and at full load. Her crew, during peace time, consisted of 29 officers and 429 enlisted men.
Detroit was powered by four Curtis steam turbines geared steam turbines, each driving one screw, using steam generated by 12 Yarrow boilers. The engines were designed to produce and reach a top speed of . She was designed to provide a range of at a speed of , but was only capable of at a speed of
Detroits main armament went through many changes while she was being designed. Originally she was to mount ten /53 caliber guns; two on either side at the waist, with the remaining eight mounted in tiered casemates on either side of the fore and aft superstructures. After America's entry into World War I the US Navy worked alongside the Royal Navy and it was decided to mount four 6-in/53 caliber guns in two twin gun turrets fore and aft and keep the eight guns in the tiered casemates so that she would have an eight gun broadside and, due to limited arcs of fire from the casemate guns, four to six guns firing fore or aft. Her secondary armament consisted of two /50 caliber anti-aircraft guns in single mounts. Detroit was initially built with the capacity to carry 224 mines, but these were removed early in her career to make way for more crew accommodations. She also carried two triple and two twin, above-water, torpedo tube mounts for torpedoes. The triple mounts were fitted on either side of the upper deck, aft of the aircraft catapults, and the twin mounts were one deck lower on either side, covered by hatches in the side of the hull.
The ship lacked a full-length waterline armor belt. The sides of her boiler and engine rooms and steering gear were protected by of armor. The transverse bulkheads at the end of her machinery rooms were thick forward and three inches thick aft. The deck over the machinery spaces and steering gear had a thickness of 1.5 inches. The gun turrets were not armored and only provided protection against muzzle blast and the conning tower had 1.5 inches of armor. Detroit carried two floatplanes aboard that were stored on the two catapults. Initially these were probably Vought VE-9s until the early 1930s when the ship may have operated OJ-2 until 1935 and Curtiss SOC Seagulls until 1940 when Vought OS2U Kingfishers were used on ships without hangars.
Armament changes
During her career Detroit went through several armament changes, some of these changes were to save weight, but others were to increase her AA armament. The lower torpedo tube mounts proved to be very wet and were removed, and the openings plated over, before the start of World War II. Another change made before the war was to increase the 3-inch guns to eight, all mounted in the ship's waist. After 1940, the lower aft 6-inch guns were removed and the casemates plated over for the same reason as the lower torpedo mounts, and in 1944, the upper fore 6-in guns were removed. The ship's anti-aircraft armament were augmented by five twin Bofors guns along with 12 Oerlikon cannons by the end of the war.