The class was designed as a development of the earlier Brooklyn -class cruisers , the size of which had been limited by the First London Naval Treaty. The start of the war led to the dissolution of the treaty system, but the dramatic need for new vessels precluded a new design, so the Cleveland s used the same hull as their predecessors, but were significantly heavier. The Cleveland s carried a main battery of twelve 6-inch mm guns in four three-gun turrets , along with a secondary armament of twelve 5 in mm dual-purpose guns.
They had a top speed of The Cleveland -class light cruisers traced their origin to design work done in the late s; at the time, light cruiser displacement was limited to 8, long tons 8, t by the Second London Naval Treaty. Following the start of World War II in September , Britain announced it would suspend the treaty for the duration of the conflict, a decision the US Navy quickly followed.
Though still neutral, the United States recognized that war was likely and the urgent need for additional ships ruled out an entirely new design, so the Cleveland s were a close development of the earlier Brooklyn -class cruisers , the chief difference being the substitution of a two-gun 5 in mm dual-purpose gun mount for one of the main battery 6 in mm gun turrets. Vincennes was feet 1 inch m long overall and had a beam of 66 ft 4 in Her standard displacement amounted to 11, long tons 11, t and increased to 14, long tons 14, t at full load.
Rated at , shaft horsepower 75, kW , the turbines were intended to give a top speed of Her crew numbered officers and enlisted men.
Two were placed forward in a superfiring pair ; the other two turrets were placed aft of the superstructure in another superfiring pair. Two of these were placed on the centerline, one directly behind the forward main turrets and the other just forward of the aft turrets. Two more were placed abreast of the conning tower and the other pair on either side of the aft superstructure.
