The Navy was already experienced in marine salvage prior to World War II. However, the Navy did not have ships specifically designed and built for salvage work when it entered WWII, and it was not until the start of the war that salvage ships become a distinct vessel type.
Then came the purpose-built Diver-class.
Built at Basalt Rock Co., Napa, Calif. — a gravel company who was in the barge building biz– 17 of the new 213-foot vessels were constructed during WWII. Fitted with a 20-ton capacity boom forward and 10-ton capacity booms aft, they had automatic towing machines, two fixed fire pumps rated at 1,000 gallons per minute, four portable fire pumps, and eight sets of “beach gear,” pre-rigged anchors, chains and cables for use in refloating grounded vessels. And of course, they were excellently equipped to support divers in the water with one double re-compression chamber and two complete diving stations aft for air diving and two 35-foot workboats.
They had a surprisingly long life and, even though they almost all left U.S. Navy service fairly rapidly in the 1970s, several gained a second career. Two went to South Korea where one, ex- USS Grapple (ARS-7) is still active as ROCS Da Hu (ARS-552) in Taiwan and another, ex-USS Safeguard (ARS-25), went to Turkey. The latter is supposedly still active as TCG Isin (A-589) though her replacement is nearing.
Three, Escape (ARS-6), Seize (ARS-26) and USS Shackle (ARS-9) went to the Coast Guard as USCGC Escape (WMEC-6), USCGC Yocona (WMEC-168) and USCGC Acushnet (WMEC-167) respectively.
Escape was sold for scrap in 2009, Seize/Yocona was sunk as a target in 2006 and Shackle/Acushnet, decommissioned in 2011 as the last Diver-class vessel in U.S. service then put up for sale for years in Anacortes, Wash with efforts afoot to save her in one form or another.
Well it looks like Shackle/Acushnet was in fact picked up last summer by a non-profit group called Ocean Guardian, who intend to keep the Coast Guard name and put her back to work as a research ship/museum/education vessel in conjunction with the National Maritime Law Enforcement Academy.
Seems like you can’t keep a good old salvage ship down.