The USS Vanadis, later known as USS Thor and USNS Thor (T-ARC-4), was originally an Artemis-class attack cargo ship (AKA-49) built by Walsh-Kaiser Co., Inc. in Providence, Rhode Island, laid down on April 18, 1945, and launched on June 8, 1945. Named after a minor planet and the goddess Freia, the vessel was commissioned into the Navy on July 9, 1945. As built, Vanadis was designed for transporting military cargo, but after decommissioning in 1946 and nearly nine years in the reserve fleet, she was reacquired and converted into a cable repair ship in 1955. Following her conversion at Bethlehem Steel in Baltimore, Maryland, she was redesignated ARC-4 and renamed Thor on November 14, 1955. She was recommissioned on January 3, 1956, and supported the installation and maintenance of the Sound Surveillance System (SOSUS) as part of Project Caesar. The ship was equipped with three 34-foot diameter cable tanks, each capable of holding approximately 20 nautical miles of armored cable or 250 nautical miles of coaxial cable. Thor's primary mission involved laying, retrieving, and repairing communication and surveillance cables across various ocean regions, including the Atlantic, Pacific, and Caribbean. Thor's design included notable features such as the capability to conduct extensive hydrographic and bathymetric surveys and support acoustic operations. However, her shallow draft of 16 feet limited her operational flexibility, especially compared to other cable ships with deeper drafts, and her hull design posed challenges for modernization efforts. Throughout her service, Thor operated extensively in the Atlantic and Pacific theaters, undertaking cable repair and laying missions near Hawaii, Midway Island, Guam, and around the Arctic Circle. She also participated in oceanographic surveys and military cable projects from the 1950s through the early 1970s. Her operational history included deployments to the Caribbean, Atlantic, and Pacific, often supporting Cold War surveillance and communication infrastructure. Decommissioned on July 2, 1973, Thor was transferred to the Military Sealift Command and operated briefly as USNS Thor until April 1974. She was then returned to the Maritime Administration and placed in the reserve fleet at Suisun Bay, California. The vessel was ultimately sold for scrap in 1977. Her service exemplifies the dual role of military ships in both cargo and specialized oceanographic and communication support during the Cold War era.

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