USNS Salvor (T-ARS-52)

USS Salvor (ARS-52) is a Safeguard-class salvage ship, the second United States Navy ship of that name.

Salvor was laid down on 16 September 1983 by Peterson Builders, Sturgeon Bay, Wisconsin; launched on 28 July 1984; and commissioned on 14 June 1986.

Salvor is the third ship of the auxiliary rescue and salvage class of vessel constructed for the US Navy. The rugged construction of this steel-hulled vessel, combined with her speed and endurance, make Salvor well-suited for rescue and salvage operations throughout the world. The hull below the waterline is ice-strengthened. Her propulsion plant can develop 4200 shaft horsepower with four Caterpillar 399 diesel engines coupled in pairs to two shafts. She is fitted with a Controllable Reversible Pitch (CRP) propeller within a Kort nozzle on each shaft. The CRP propeller/Kort nozzle combination produces greater thrust and more maneuverability control than conventional propellers. Salvor is also configured with a bow thruster which provides athwartship thrust for additional control of the bow when the ship's speed is less than five knots (9 km/h).

In 1995 and again in 2000, Salvor was the United States Pacific Fleet's winner of the Marjorie Sterrett Battleship Fund Award for most battle-ready ship of her type.

USS Salvor was decommissioned and transferred to the Military Sealift Command in January 2007. Salvor was redesignated as USNS Salvor (T-ARS 52). The ship has undergone modifications for civilian crewing as well as automation and control system upgrades at Puget Sound Naval Shipyard.

Mission and capabilities
Like all Safeguard class rescue and salvage ships, Salvor serves as an element of the United States Navy's Combat Logistics Support Force and provides rescue and salvage services to the fleet at sea. She also supported the protection of forces ashore through post-assault salvage operations in close proximity to the shore. She is designed to perform combat salvage, lifting, towing, off-ship firefighting, manned diving operations, and emergency repairs to stranded or disabled vessels.

Salvage of disabled and stranded vessels
Disabled or stranded ships might require various types of assistance before retraction or towing can be attempted. In her 21,000 cuft salvage holds, Salvor carries transportable cutting and welding equipment, hydraulic and electric power sources, and de-watering gear. Salvor also has salvage and machine shops, and hull repair materials to effect temporary hull repairs on stranded or otherwise damaged ships.

Retraction of stranded vessels
Stranded vessels can be retracted from a beach or reef by the use of Salvor towing machine and propulsion. Additional retraction force can be applied to a stranded vessel through the use of up to six legs of beach gear, consisting of 6000 lb STATO anchors, wire rope, chain, and salvage buoys. In a typical configuration, two legs of beach gear are rigged on board Salvor, and up to four legs of beach are rigged to the stranded vessel.

In addition to the standard legs of beach gear, Salvor carries 4 spring buoys. The spring buoys are carried beneath the port and starboard bridge wings and are painted bright orange. Each spring buoy weighs approximately 3100 lb, is 10 ft long and 6 ft in diameter, provides a net buoyancy of 7½ tons, and can withstand 125 tons of pull-through force. The spring buoys are used with beach gear legs rigged from a stranded vessel when deep water is found seaward of the stranded vessel.

Towing
The centerpiece of Salvor towing capability is an Almon A. Johnson Series 322 double-drum automatic towing machine. Each drum carries 3000 ft of 2+1/4 in drawn galvanized, 6X37 right-hand lay, wire-rope towing hawsers, with closed zinc-poured sockets on the bitter end. The towing machine uses a system to automatically pay-in and pay-out the towing howser to maintain a constant strain.

The automatic towing machine also includes a Series 400 traction winch that can be used with synthetic line towing hawsers up to 14 inches in circumference. The winch has automatic payout but only manual recovery.

The Salvor caprail is curved to fairlead and prevent chafing of the towing hawser. It includes two vertical stern rollers to tend the towing hawser directly aft and two Norman pin rollers to prevent the towing hawser from sweeping forward of the beam at the point of tow. The stern rollers and Norman pins are raised hydraulically and can withstand a lateral force of 50000 lb at mid barrel.

Two tow bows provide a safe working area on the fantail during towing operations.

Manned diving operations
Salvor has several diving systems to support different types of operations. Divers descend to diving depth on a diving stage that is lowered by one of two powered davits.

The diving locker is equipped with a double-lock hyperbaric chamber that can be used for recompression after deep dives or for the treatment of divers suffering from decompression sickness.

The MK21 MOD1 diving system supports manned diving to depths of 190 ft on surfaced-supplied air. A fly-away mixed gas system can be used to enable the support of diving to a maximum depth of 300 ft.

The MK20 MOD0 diving system allows-surface supplied diving to a depth of 60 ft with lighter equipment.

Salvor carries SCUBA equipment for dives that require greater mobility than is possible in tethered diving.

Mines
Naval mine laying and recovery.

Recovery of submerged objects
In addition to her two main ground tackle anchors (6000 lb Navy standard stockless or 8000 lb balanced-fluke anchors) Salvor can use equipment associated with her beach gear to lay a multi-point open water moor to station herself for diving and ROV operations.

A typical four-point-moor consists of an X pattern with four Stato Anchors at the outside corners and Salvor at the center, made fast to a spring buoy for the close end of each mooring leg with synthetic mooring lines. Using her capstans, Salvor can shorten or lengthen the mooring line for each leg and change her position within the moor.

As built Salvor had a 7.5-ton capcacity boom on a forward kingpost, however the kingpost and boom are being replaced by a 10,0000-pound deck crane. She has 40-ton capacity boom on her aft kingpost.

Heavy Lift
Salvor has heavy lift system that consists of large bow and stern rollers, deck machinery, and tackle. The rollers serve as low-friction fairlead for the wire rope or chain used for the lift. The tackle and deck machinery provide up to 75 tons of hauling for each lift. The two bow rollers can be used together with linear hydraulic pullers to achieve a dynamic lift of 150 tons. The stern rollers can be used with the automatic towing machine to provide a dynamic lift of 150 tons. All four rollers can be used together for a dynamic lift of 300 tons or a static tidal lift of 350 tons.

"Salvor" also has two auxiliary bow rollers, which can support of 75 ton lift when used together.

Off-ship fire-fighting
Salvor Has three manually operated fire monitors, one on the forward signal bridge, one on on the aft signal bridge, and one on the forecastle, that can deliver up to 1000 gallons per minute of seawater or aqueous film forming foam (AFFF). When originally built, Salvor had a fourth remotely controlled fire monitor mounted on her forward kingpost, but this was later removed. Salvor has a 3600 gallon foam tank.

Emergency ship salvage material
In addition to the equipment carried by Salvor, the US Navy Supervisor of Salvage maintains a stock of additional emergency fly-away salvage equipment that can be deployed aboard the salvage ships to support a wide variety of rescue and salvage operations.

Operational accomplishments
Between 1987 and 2001, Salvor has provided rescue or assistance to ships at sea in seven instances. Two cases involved collisions near Hawaii: the USNS Safeguard (T-ARS-50) boat accident in August 1987, and the Collision of USS Greeneville (SSN-772) with Eihme Maru between February and November 2001. Salvor also assisted in the Exxon Houston grounding near Barbers Point, Hawaii, in March 1989, and the Kamalu barge fire in May 1989. On three occasions, Salvor has assisted a ship at sea that has suffered a catastrophic equipment loss: recovering the primary towing pendant of the Ex-USS Duncan (FFG-10)/USNS Navajo (T-ATF-166) in January 1995, the anchor chain of the USS Willamette (AO-180) in February 1995, and the towed sonar array of the USS Los Angeles (SSN-688) in June 1996. The ship was also involved in the rescue effort after the ROKS Cheonan sinking.

During the same time, Salvor participated in seven sea-recoveries of submerged military aircraft, including an A-6E Intruder (VA-145) in Puget Sound, Washington, a UH-46D Sea Knight from a world-record depth 17,251 ft near Wake Island, a SH-60 Seahawk, an F/A-18C Hornet (VFA-22) near San Diego, and two United States Air Force F-16 Falcons in Korean waters and the Sea of Japan.

Other salvage operations undertaken by Salvor include repairing the propeller blades of HMAS Darwin (FFG 04), repairing the hull of BRP Rajah Humabon, recovering a LARC-V amphibious vehicle, recovering and disposing of a 1000 lb Mark 83 bomb, pumping out oil leaking from the wreck of USS Mississinewa (AO-59), and exploring the wreck of the USS Lagarto (SS-371) in the Gulf of Thailand.