USNS Grasp (T-ARS-51)
Encyclopedia
USNS Grasp (T-ARS-51) is a , the second United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
ship of that name.
Grasp was laid down on 30 March 1983 by Peterson Builders, Sturgeon Bay, Wisconsin
Sturgeon Bay, Wisconsin
Sturgeon Bay is a city in and the county seat of Door County, Wisconsin, United States. The population was 9,437 at the 2000 census. It is located at the natural end of Sturgeon Bay, although the Sturgeon Bay Ship Canal was built across the remainder of the Door Peninsula.-Geography:Sturgeon Bay is...
; launched
Ship naming and launching
The ceremonies involved in naming and launching naval ships are based in traditions thousands of years old.-Methods of launch:There are three principal methods of conveying a new ship from building site to water, only two of which are called "launching." The oldest, most familiar, and most widely...
on 2 May 1985; and commissioned
Ship commissioning
Ship commissioning is the act or ceremony of placing a ship in active service, and may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most commonly applied to the placing of a warship in active duty with its country's military...
on 14 December 1985.
Grasp is the second ship of the newest auxiliary rescue and salvage class of vessels constructed for the US Navy. The rugged construction of this steel-hulled vessel, combined with her speed and endurance, make Grasp well-suited for rescue and salvage operations throughout the world. The hull below the waterline is ice-strengthened.
Grasp sister ships are , , and .
On 19 January 2006 USS Grasp was transferred to the Military Sealift Command
Military Sealift Command
The Military Sealift Command is a United States Navy organization that controls most of the replenishment and military transport ships of the Navy. It first came into existence on 9 July 1949 when the Military Sea Transportation Service became solely responsible for the Department of Defense's...
as USNS Grasp (T-ARS-51).
Following the 2010 Haiti earthquake
2010 Haiti earthquake
The 2010 Haiti earthquake was a catastrophic magnitude 7.0 Mw earthquake, with an epicentre near the town of Léogâne, approximately west of Port-au-Prince, Haiti's capital. The earthquake occurred at 16:53 local time on Tuesday, 12 January 2010.By 24 January, at least 52 aftershocks...
, the Grasp was staffed with a team of structural engineers from the US Army Corps of Engineers and dispatched on 16 January 2010 to Haiti's
Haiti
Haiti , officially the Republic of Haiti , is a Caribbean country. It occupies the western, smaller portion of the island of Hispaniola, in the Greater Antillean archipelago, which it shares with the Dominican Republic. Ayiti was the indigenous Taíno or Amerindian name for the island...
devastated seaport
Port international de Port-au-Prince
The is the seaport in the capital of Haiti, Port-au-Prince. It suffered catastrophic damage in the 2010 Haiti earthquake.Some of docks and warehouses are operated by the government's Autorité Portuaire Nationale , and some are run by private companies.- History :On 13 June 1872, a German fleet...
in Port-au-Prince as part of Operation Unified Response
Operation Unified Response
Operation Unified Response is the United States military's response to the 2010 Haiti earthquake. It is being conducted by Joint Task Force Haiti and commanded by United States Southern Command Military Deputy Commander Lieutenant General Ken Keen, although the overall U.S...
to assess for and complete emergency structural repairs so that large military and civilian cargo vessels may unload their rescue aid shipments more efficiently.
Mission and capabilities
Like all Safeguard class rescue and salvage ships, Grasp 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 21000 cubic feet (594.7 m³) salvage hold, Grasp carries transportable cutting and welding equipment, hydraulic and electric power sources, and de-watering gear. Grasp 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 Grasp's 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 6,000 pound STATO anchors, wire rope, chain, and salvage buoys. In a typical configuration, two legs of beach gear are rigged on board Grasp, and up to four legs of beach are rigged to the stranded vessel.In addition to the standard legs of beach gear, Grasp carries 4 spring buoys. The spring buoys are carried beneath the port and starboard bridge wings. Each spring buoy weighs approximately 3100 pounds, is 10 feet (3 m) long and 6 feet (1.8 m) 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
Grasp's propulsion machinery provides a bollard pullBollard pull
Bollard pull is a value that allows the comparison of the pulling force of watercraft, particularly tugboats. A mooring bollard may be used as a point of attachment for measuring the force, or pull of the craft.-Background:...
(towing force at zero speed and full power) of 68 tons.
The centerpiece of Grasp's towing capability is an Almon A. Johnson Series 322 double-drum automatic towing machine. Each drum carries 3000 feet (914.4 m) of 2+1/4 in drawn galvanized, 6×37 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 hawser 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 traction winch has automatic payout but only manual recovery.
The Grasp's caprail is curved to fairlead and prevent chaffing 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 pounds (22,679.6 kg) at mid barrel.
Two tow bows provide a safe working area on the fantail during towing operations.
Manned diving operations
Grasp has a 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 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 feet (57.9 m) 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 feet.
The MK20 MOD0 diving system allows-surface supplied diving to a depth of 60 feet (18.3 m) with lighter equipment.
Grasp carries SCUBA
Scuba diving
Scuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater....
equipment for dives that require greater mobility than is possible in tethered diving.
Recovery of submerged objects
In addition to her two main ground tackle anchorAnchor
An anchor is a device, normally made of metal, that is used to connect a vessel to the bed of a body of water to prevent the vessel from drifting due to wind or current. The word derives from Latin ancora, which itself comes from the Greek ἄγκυρα .Anchors can either be temporary or permanent...
s (6000 pound Navy standard stockless or 8000 pound balanced-fluke anchors) Grasp 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 Grasp at the center, made fast to a spring buoy for the close end of each mooring leg with synthetic mooring lines. Using her capstans, Grasp can shorten or lengthen the mooring line for each leg and change her position within the moor.
Grasp has a 7.5-ton capacity boom on her forward kingpost and a 40-ton capacity boom on her aft kingpost.
Heavy Lift
Grasp 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.Grasp also has two auxiliary bow rollers, which can support of 75 ton lift when used together.