{{short description|Cargo ship of the United States Navy}} {{Use American English|date=October 2024}} {{Use dmy dates|date=October 2024}} {{Infobox ship |section1={{Infobox ship/image |image=USS Thor (ARC-4) underway in Chesapeake Bay (USA) on 12 December 1955 (7575699).jpg |image_caption=USS ''Thor'' as a cable repair ship }}
|section2={{Infobox ship/career |hide_header= |country=United States |flag={{USN flag|1973}} |name=''Vanadis'' |namesake=The asteroid Vanadis or Freia |ordered= |builder=Walsh-Kaiser Company, Providence, Rhode Island |laid_down= 18 April 1945 |launched= 8 June 1945 |acquired= |commissioned= 9 July 1945 |decommissioned= 27 March 1946 |in_service= |out_of_service= |struck= 5 June 1946 |renamed= |reclassified= |homeport= |motto= |nickname= |honours= |fate= Transferred to the Maritime Commission, 2 July 1946 |notes= }}
|section3={{Infobox ship/career |hide_header=title |name=''Thor'' |namesake=Thor, the Norse god of thunder |acquired=14 April 1955 |recommissioned= 3 January 1956 |decommissioned= 2 July 1973 |in_service=2 July 1973 (Military Sealift Command) |out_of_service=April 1974 |struck= |renamed= |reclassified= |homeport= |motto= |nickname= |honours= |fate=Sold for scrapping 22 September 1977 |notes= }}
|section4={{Infobox ship/characteristics |hide_header= |header_caption= |class={{sclass|Artemis|attack cargo ship}} |type=S4–SE2–BE1 |displacement=*{{convert|4087|LT|t|0|abbr=on}} light *{{convert|7080|LT|t|0|abbr=on}} full |length={{convert|426|ft|m|abbr=on}} |beam={{convert|58|ft|m|abbr=on}} |draft={{convert|16|ft|m|abbr=on}} |propulsion= |speed={{convert|16.9|kn|lk=in}} |range= |complement=303 officers and enlisted |armament=*1 × 5"/38 caliber gun mount *4 × twin Bofors 40 mm L/60 gun mounts *10 × Oerlikon 20 mm cannon mounts |armor= |notes= }} }} '''USS ''Thor''''' was a cable repair ship that supported Project Caesar, the unclassified name for installation of the Sound Surveillance System (SOSUS). Originally the {{sclass|Artemis|attack cargo ship}} '''''Vanadis'' (AKA-49)''' which was briefly in commission from 9 July 1945 to 27 March 1946, it was converted in 1955 after nine years in the reserve fleet.
''Thor'', named after the Germanic god of thunder, was commissioned on 3 January 1956 and served in that capacity until 2 July 1973 when transferred to the Military Sealift Command (MSC) for brief operation as '''USNS ''Thor'' (T-ARC-4)''' until April 1974 when the ship was returned to the Maritime Administration for disposal. After removal of cable machinery the ship was eventually sold for scrap on 22 September 1977.
''Thor'' was one of four Navy cable ships supporting military cable projects from the 1950s until 1984 with construction of {{ship|USNS|Zeus|T-ARC-7|2}}. The others were {{ship|USS|Aeolus|ARC-3|2}}, the other transport conversion, and the two Army designed cable ships, the only ships in the Navy designed and built as cable ships, {{ship|USNS|Albert J. Myer||2}} and {{ship|USNS|Neptune|ARC-2|2}} which were modernized in the 1980s.
==USS ''Vanadis'', 1945–1946== ''Vanadis'' (AKA-49) was laid down on 18 April 1945 under a Maritime Commission contract (MC hull 1910) at Providence, Rhode Island, by the Walsh-Kaiser Co., Inc. and launched on 8 June 1945 sponsored by Mrs. J. Henry Gill. Like most ships of its class, the ship was named for a minor planet (asteroid), 240 Vanadis or 76 Freia (''Vanadis'' is an alternative poetic name for ''Freia'', the Germanic goddess of love and beauty). The Navy acquired the ship on 9 July 1945 with commissioning the same day.<ref name=DANFS>{{cite DANFS |url=https://www.history.navy.mil/research/histories/ship-histories/danfs/t/thor.html |title=Thor |author=Naval History And Heritage Command |work=Dictionary of American Naval Fighting Ships |publisher=Naval History And Heritage Command |access-date=22 February 2020}}</ref>
Following shakedown out of Hampton Roads, ''Vanadis'' arrived at Newport, Rhode Island, on 4 August and began shuttling back and forth between that port and Hampton Roads. In mid-December, the attack cargo ship headed for the Gulf of Mexico. After visiting Mobile, Alabama; Gulfport, Mississippi; and Jacksonville, Florida, she arrived at Boston. On 6 February, she reported to the Commandant, 1st Naval District, for inactivation. ''Vanadis'' was placed out of commission on 27 March 1946. Her name was struck from the Navy List on 5 June 1946; and, on 2 July, she was transferred to the Maritime Commission.<ref name=DANFS/>
==USS ''Thor''== After almost nine years of inactivity — berthed with the National Defense Reserve Fleet at James River, Virginia — ''Vanadis'' was reacquired by the Navy on 14 April 1955 and reinstated on the Navy List as AKA-49. On 30 June, she entered the Bethlehem Steel Co.'s yard at Baltimore, Maryland, for conversion to a cable repair ship. She was redesignated ARC-4 and renamed '''''Thor''''' on 14 November 1955. On 3 January 1956, ''Thor'' completed her conversion and was recommissioned.<ref name=DANFS/> ''Thor'' was converted to support the installation of the Sound Surveillance System and other defense cable projects. The system and name were at the time classified with the unclassified name Project Caesar being given to the installation and support of the system.<ref name=ICAA>{{cite web |title=Integrated Undersea Surveillance System (IUSS) History 1950 - 2010 |publisher=IUSS * CAESAR Alumni Association |url=http://www.iusscaa.org/history.htm |access-date=20 February 2020}}</ref>
=== Function === 150px|thumb|right|Navy cable repair ship cable control as installed mid 1950s seen aboard ''Thor''.
The ship was principally used to transport, deploy, retrieve and repair cables and to conduct acoustic, hydrographic, and bathymetric surveys under Project Caesar.<ref name=ICAA/> Civilian specialists are involved during cable or surveying operations for the technical work.<ref name=AHM473>{{cite magazine |date=April 1973 |title=Bridging the Underwater Communications System |magazine=All Hands |issue=625 |pages=16–19 |url=https://ipv6.navy.mil/ah_online/archpdf/ah197304.pdf |archive-url=https://web.archive.org/web/20161221012701/http://ipv6.navy.mil/ah_online/archpdf/ah197304.pdf |url-status=dead |archive-date=21 December 2016 |access-date=20 February 2020}}</ref><ref name=AHM164>{{cite magazine |date=January 1964 |title=Underseas Cable Layer |magazine=All Hands |issue=564 |url=https://ipv6.navy.mil/ah_online/archpdf/ah196401.pdf |archive-url=https://web.archive.org/web/20161221004810/http://ipv6.navy.mil/ah_online/archpdf/ah196401.pdf |url-status=dead |archive-date=21 December 2016 |access-date=20 February 2020}}</ref><ref group=note>SOSUS and both operations and actual linkage of Project Caesar to SOSUS was at the time classified and tightly controlled. The system was covered as "oceanographic research" and the cable operations were not associated with undersea surveillance systems. Thus any public information, such as the referenced ''All Hands'' articles, did not describe the true nature of the operations. The ''All Hands'' January 1964 article emphasizes the cover story with the purpose being to connect remote ocean observation centers with shore stations.</ref>
The ''Thor'' and ''Aeolus'' had three {{cvt|34|ft|m|1|abbr=on}} diameter cable tanks each with a capacity of about {{cvt|20|nmi| mi km}} of five inch armored cable or {{cvt|250|nmi| mi km}} of coaxial cable.<ref group=note>See USS ''Aeolus'' Association's [https://ussaeolus.com/wp-content/uploads/photo-gallery/DSC04649.JPG photo of Caesar cable types].</ref> Cable being laid was under constant test by civilian experts in the ships cable test room. Cable ships with bow sheaves only required towing astern for some long runs of cable resulting in the unusual feature of two sets of running lights suitable for the stern becoming the effective bow.<ref name=AHM164/>
By the late 1970s the two ''Artemis'' class transports converted to cable ships were in need of modernization or replacement. Some shortcomings in design worked against modernization even though two other ships of the same age were slated for major modernization. The class had been designed with a relatively shallow draft of {{convert|16|ft|m|abbr=on}}, least draft of the attack transports that had drafts from {{convert|26|ft|m|abbr=on}} to {{convert|28|ft|m|abbr=on}}.<ref>{{cite book |date=1 September 1945 |title=ONI 222-US: United States Naval Vessels : Official United States Navy Reference Manual |publisher=Office of Naval Intelligence |pages=189–191 |url=https://books.google.com/books?id=Epii9ppEzeYC&pg=PA189 |access-date=22 February 2020}}</ref><ref group=note>A {{convert|10|ft|m|abbr=on}} lesser draft might have some advantages in an attack transport allowing closer approach to beaches.</ref> Compared to the {{convert|25|ft|m|abbr=on}} draft of the smaller {{ship|USNS|Albert J. Myer||2}} and {{ship|USNS|Neptune|ARC-2|2}}, designed as an Army cable layers late in World War II and the only Navy ships designed as cable ships, this was a disadvantage in a cable ship's loading and operations.<ref>{{cite DANFS |url=https://www.history.navy.mil/research/histories/ship-histories/danfs/a/albert-j-myer.html |title=Albert J. Myer |author=Naval History And Heritage Command |work=Dictionary of American Naval Fighting Ships |publisher=Naval History And Heritage Command |access-date=22 February 2020}}</ref><ref>{{cite DANFS |url=https://www.history.navy.mil/research/histories/ship-histories/danfs/n/neptune-iv.html |title=Neptune IV (ARC-2) |author=Naval History And Heritage Command |work=Dictionary of American Naval Fighting Ships |publisher=Naval History And Heritage Command |access-date=22 February 2020}}</ref><ref name=CAS>{{cite book |last=Committee on Armed Services (U.S. Senate) |year=1978 |title=Department of Defense Authorization for Appropriations for Fiscal Year 1979 |location=Washington, D.C. |publisher=Government Printing Office |pages=4244–4246 |url=https://books.google.com/books?id=grmENiGabHEC&pg=PA4244 |access-date=22 February 2020}}</ref> Both of those ships, built the same year and as old, were essentially rebuilt to extend their service life but the two larger ships were not going to be modernized. The shallow draft, which also hindered bathymetric survey work due to shallow transducer depth, and large sail area of the exposed hull and superstructure made stopped or very low speed cable operations hazardous. Thrusters could not be built into the shallow draft hulls and tugs had to be used for some operations. The ships had no stern cable capability and could not effectively be modernized for that capability. Finally, the ships could not carry a full load of cable and a full load of fuel without exceeding maximum draft limits and modernization would only add to that limitation by adding weight.<ref name=CAS/>
==Service history== === 1956–1961 === The cable repair ship operated in the Atlantic through 1956. In February 1957, she reported to the Pacific Fleet and, until the fall of 1958, operated out of San Francisco repairing and laying cables. She returned to the Atlantic in September 1958 and served there until the summer of 1961, when she was temporarily assigned to the Pacific again. The cable repair ship returned to operations in the Atlantic in December.<ref name=DANFS/>
=== 1962–1969 === 250px|thumb|right|USS ''Thor'' (ARC-4) lays the shore end of a cable, circa 1963. Floats hold the cable in position for sinking. Following an overhaul at Boston in the spring of 1962, ''Thor'' deployed to the Pacific once more for cable repair operations in the northern reaches of that ocean. In October, she returned to the eastern side of the Isthmus of Panama and busied herself with cable repair duties and oceanographic projects in the Caribbean. For the next five and one-half years, ''Thor'' continued to repair and lay cables in the western Atlantic and in the West Indies. Occasionally, she also participated in more oceanographic projects. During that half decade, she ranged as far north as Nova Scotia and as far south as the Caribbean. Periodically, she also conducted operations in the Gulf of Mexico.<ref name=DANFS/>
On 20 April 1968, the ship departed Norfolk and steamed, via the Panama Canal and San Diego, for the Central Pacific. She conducted special operations in the vicinity of Midway Island and returned to Hawaii on 16 June for several days before departing Pearl Harbor on the 24th for the Marianas. She reached Guam on 5 July and spent the next month repairing cable around that island. She returned to Pearl Harbor on 13 August and operated in the Hawaiian Islands until she headed back toward the mainland on 7 November. Following a brief stop at Long Beach, California, ''Thor'' returned to Norfolk on 6 December.<ref name=DANFS/>
Over the next four years, ''Thor'' deployed to the Pacific three times. In August 1969, after seven months of operations along the east coast, she headed, via the Panama Canal and San Diego, to Pearl Harbor. Through November, she conducted operations near Midway Island and then returned to the Atlantic via Pearl Harbor, Long Beach, and the Panama Canal.<ref name=DANFS/>
=== 1970–1974 === In February 1970, she entered the Bethlehem Steel Shipyard in Boston to begin a year-long overhaul and repair period. In mid-February 1971, the cable repair ship resumed normal operations until late June when she deployed to the Pacific once more. She reached Hawaii on 29 July and departed again on 9 August for cable operations in the northernmost reaches of the Pacific, near the Aleutians chain. She completed those repairs late in the month and, after visits to Esquimalt, British Columbia, and San Diego, transited the canal on 20 September and arrived in Portsmouth, New Hampshire, eight days later. During the first seven months of 1972, the cable repair ship operated along the eastern seaboard again. On 24 July, ''Thor'' departed Norfolk for her last assignment in the Pacific Ocean. She arrived at Alameda, California, on 11 August and conducted cable laying operations from there into late November. On the 24th, the ship cleared Alameda. She passed through the Panama Canal on 4 December and arrived back at Portsmouth on the 12th.<ref name=DANFS/>
On 17 January 1973, ''Thor'' embarked upon her last overseas cruise as a commissioned ship in the Navy. She arrived in Swansea, Wales, 10 days later and, after two days in port, put to sea for cable operations. From 14 February to 18 February, she visited the Submarine Base at Holy Loch, Scotland, before resuming cable operations near the Arctic Circle. She completed her assignment at the end of the month and, after another visit to Holy Loch during the first week in March, headed back to the United States. On 17 March, she returned to the Portsmouth Naval Shipyard to begin preparations for decommissioning incident to her transfer to the Military Sealift Command.<ref name=DANFS/>
''Thor'' was decommissioned at Portsmouth on 2 July 1973 and simultaneously transferred to the custody of the Military Sealift Command. '''USNS ''Thor'' (T-ARC-4)''' operated with the Military Sealift Command, primarily in the Pacific, until April 1974.<ref name=DANFS/>
==Disposal== ''Thor'' was returned to the Maritime Administration to be placed in reserve. Berthed with the National Defense Reserve Fleet at Suisun Bay, California 31 July 1975. The ship was withdrawn 2 May 1977 for removal of cable machinery and returned to the reserve fleet on 1 June 1977. The ship was sold to National Metal & Steel Corporation for scrapping on 22 September 1977 as one of four ships sold for a total of $565,183.92.<ref>{{cite web |url=https://vesselhistory.marad.dot.gov/ShipHistory/Detail/4873 |title=THOR (ARC-4/T-ARC-4) |author=Maritime Administration |work=Ship History Database Vessel Status Card |publisher=U.S. Department of Transportation, Maritime Administration |access-date=22 February 2020}}</ref>
== Footnotes == {{reflist|group=note}}
==References== {{reflist}} *{{DANFS|http://www.history.navy.mil/research/histories/ship-histories/danfs/v/vanadis.html|http://www.history.navy.mil/research/histories/ship-histories/danfs/t/thor.html}}
==External links== *{{navsource|10/02/02049}} *[https://web.archive.org/web/20060620071629/http://ussrankin.org/id352.htm 51 Years of AKAs]
{{Artemis class attack cargo ship}} {{Aeolus class cable repair ship}}
{{DEFAULTSORT:Thor, USS}} Category:Artemis-class attack cargo ships Category:Ships built in Providence, Rhode Island Category:1945 ships Category:World War II amphibious warfare vessels of the United States Category:Aeolus-class cable repair ships Category:Cold War auxiliary ships of the United States