The USS Dreadnaught (ID-1951), later known as YT-534 and YNG-21, was a United States Navy tug constructed in 1917 by Union Iron Works in San Francisco for the Rolph Navigation and Coal Company. Originally a commercial tug, she was purchased by the Navy on 17 May 1917 to support wartime operations. After fitting out at Mare Island Navy Yard, she was commissioned as USS Dreadnaught on 31 January 1918. The vessel measured as a typical harbor tug of her era, capable of towing barges and ships, with a robust design suited for both harbor and convoy escort duties during World War I. Her service record begins with her departure from San Francisco in late February 1918, towing coal barges to Norfolk, Virginia, by April. She then moved to New London, Connecticut, where she was assigned to the Patrol Force of the Atlantic Fleet. Throughout her wartime service, Dreadnaught participated in convoy escort missions, notably escorting submarine chasers to the Azores and assisting in towing operations, such as pulling SS Luckenbach from the Azores to Bermuda and towing USS Goliah from Bermuda to New York. During the latter part of World War I, she escorted convoy groups across the Atlantic, including escorting the Army tug Cuba to Brest, France, where she operated on harbor duty, towing barges and ships between French ports until March 1919. After the war, she continued towing duties in the Azores and returned to the United States in August 1919, eventually arriving at Norfolk, Virginia, for an overhaul. In 1920, Dreadnaught was reclassified as a harbor tug (YT-34) and assigned to the 12th Naval District for operations in San Francisco. Although decommissioned on 14 March 1922, she continued her duties in a non-commissioned status. Later, she was reclassified as a gate tender (YNG-21) in October 1940, serving as an anti-submarine barrier gate craft. She was stricken from the Navy List in September 1944 and was reportedly destroyed shortly thereafter, marking the end of her maritime service.

This description has been generated using GPT-4.1-NANO based on the Vessel's wikidata information and then modified by ShipIndex.org staff.