The Delaware-class battleships of the United States Navy were the second class of American dreadnoughts. With this class, the limit imposed on capital ships by the United States Congress was waived, which allowed designers at the Navy's Bureau of Construction and Repair to correct what they considered flaws in the preceding and produce ships not only more powerful but also more effective and rounded overall. Launched in 1909, these ships became the first in US naval history to exceed . The Delawares carried a battery of ten guns in five turrets, an increase of two guns over the South Carolinas. With these ships, the US Navy re-adopted a full-fledged medium-caliber weapon for anti-torpedo boat defense. While the gun was smaller than that used by other major navies, this would, with few exceptions, become the standard medium-gun caliber for the US Navy for the better part of the 20th century. As for speed, the Delawares were capable of , a significant improvement over the earlier class's . This would become the speed for all American standard-type battleships. Propulsion systems were mixed; while was fitted with steam turbines, retained triple-expansion engines. Direct-drive turbines were much less fuel-efficient, a significant concern for a Navy with Pacific responsibilities but lacking Britain's extensive network of coaling stations. These ships saw varied service during their careers. During World War I, Delaware was part of Battleship Division Nine of the US Atlantic Fleet, and was assigned to the British Grand Fleet. She escorted convoys and participated in the blockade of the German High Seas Fleet. In contrast, North Dakota remained on the American coast throughout the war, due in part to worries about her troublesome turbine engines. Post-war, they conducted training cruises with the US Atlantic Fleet. In 1924, Delaware was broken up for scrap metal in accordance with the Washington Naval Treaty of 1922. North Dakota survived until 1931, when she too was scrapped, under the terms of the 1930 London Naval Treaty. Design Prompted by the launch of and misinformation about , the US Navy and Congress faced what they perceived as a vastly better battleship than the two battleships then under construction, which were designed under tonnage constraints that Congress had imposed on capital ships. Actually, the South Carolinas were inferior only in speed to Dreadnought; they carried fewer heavy guns but, unlike Dreadnought, could bring all of them to bear on the broadside.