USNS Neptune (ARC-2), was the lead ship in her class of cable repair ships in U.S. Naval service. The ship was built by Pusey & Jones Corp. of Wilmington, Delaware, Hull Number 1108, as the USACS William H. G. Bullard named for Rear Adm. William H. G. Bullard. She was the first of two Maritime Commission type S3-S2-BP1 ships built for the US Army Signal Corps near the end of World War II. The other ship was the Albert J. Myer, which later joined her sister ship in naval service as the USNS Albert J. Myer (T-ARC-6).

USS Thor was a cable repair ship that supported Project Caesar, the unclassified name for installation of the Sound Surveillance System (SOSUS). Originally the Artemis-class 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.