USS Concord (CL-10) was an light cruiser, originally classified as a scout cruiser, of the United States Navy. She was the fourth Navy ship named for the town of Concord, Massachusetts, the site of the first battle of the American Revolution. She spent the first nine years of her career in the Atlantic as part of the Scouting Force. Concord transferred to the Pacific in 1932 and spent the rest of her career, except for the winter of 1938–1939, stationed there. Her home port moved to Pearl Harbor in April 1940, but she escaped the attack on Pearl Harbor because she was in San Diego for an overhaul.
Built in Philadelphia, Pennsylvania
Concord was authorized on 29 August 1916, and assigned to William Cramp & Sons, Philadelphia on 30 July 1917. She was laid down on 29 March 1920, and launched on 15 December 1921, sponsored by Miss H. Butterick. Concord was commissioned on 3 November 1923, with future Admiral, Captain Orin G. Murfin in command.
Concord 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.
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.
Armament changes
During her career Concord 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. She took part in Presidential Fleet Reviews taken by Franklin D. Roosevelt on 30 September 1935 and 12 July 1938, and joined in fleet exercises in the Hawaiian area, in the Canal Zone, and off Alaska. After operating on the east coast in the winter of 1938–39, she returned to Pacific operations, and from 1 April 1940, was based at Pearl Harbor for a training schedule which intensified as war came closer. and caused considerable damage, which was repaired at Balboa, Panama.