USNS Safeguard (T-ARS-50)
Encyclopedia

USS Safeguard (ARS-50) 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.

Safeguard was laid down on 8 November 1982 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 12 November 1983; 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 17 August 1985.

Safeguard is the lead 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 Safeguard well-suited for rescue and salvage operations throughout the world. The hull below the waterline is ice-strengthened.

USS Safeguard's sister ships are the , , and .

On 26 September 2007 USS Safeguard 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 Safeguard (T-ARS-50).

Mission and capabilities

Like all Safeguard class rescue and salvage ships, Safeguard 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, Safeguard carries transportable cutting and welding equipment, hydraulic and electric power sources, and de-watering gear. Safeguard 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 Safeguard'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 6000 pounds (2,721.6 kg) STATO anchors, wire rope, chain, and salvage buoys. In a typical configuration, two legs of beach gear are rigged on board Safeguard, and up to four legs of beach are rigged to the stranded vessel.

In addition to the standard legs of beach gear, Safeguard carries 4 spring buoys. The spring buoys are carried beneath the port and starboard bridge wings. Each spring buoy weighs approximately 3100 pounds (1,406.1 kg), 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

Safeguard's propulsion machinery provides a bollard pull
Bollard 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 Safeguard'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 howser to maintain a constraint 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 Safeguard's 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 preven 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

Safeguard 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 decompression 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 (91.4 m).

The MK20 MOD0 diving system allows-surface supplied diving to a depth of 60 feet (18.3 m) with lighter equipment.

Safeguard 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 anchor
Anchor
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 pounds (2,721.6 kg) Navy standard stockless or 8000 pounds (3,628.7 kg) balanced-fluke anchors] Safeguard 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 Safeguard at the center, made fast to a spring buoy for the close end of each mooring leg with synthetic mooring lines. Using her capstans, Safeguard can shorten or lengthen the mooring line for each leg and change her position within the moor.

Safeguard has a 7.5-ton-capacity boom on her forward kingpost and a 40-ton-capacity boom on her aft kingpost.

Heavy Lift

Safeguard 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.

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

Off-ship fire-fighting

Safeguard 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 1,000 gallons per minute of seawater or aqueous film forming foam (AFFF) When originally built, Safeguard had a fourth remotely controlled fire monitor mounted on her forward kingpost, but this was later removed. Safeguard has a 3,600-gallon foam tank.

Emergency ship salvage material

In addition to the equipment carried by Safeguard, 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.

Service

During Operation Tomodachi
Operation Tomodachi
is a United States Armed Forces assistance operation to support Japan in disaster relief following the 2011 Tōhoku earthquake and tsunami. As of March 22, 2011, twenty U.S. naval ships, 140 aircraft, and 19,703 Marines and Sailors were involved in humanitarian assistance and disaster relief...

, this ship was one of several participating in disaster relief after the 2011 Tōhoku earthquake and tsunami
2011 Tōhoku earthquake and tsunami
The 2011 earthquake off the Pacific coast of Tohoku, also known as the 2011 Tohoku earthquake, or the Great East Japan Earthquake, was a magnitude 9.0 undersea megathrust earthquake off the coast of Japan that occurred at 14:46 JST on Friday, 11 March 2011, with the epicenter approximately east...

. Divers from the ship helped clear the port at Hachinohe, Aomori
Hachinohe, Aomori
- Neighbouring municipalities :Aomori Prefecture*Sannohe District**Hashikami**Gonohe**Nanbu*Kamikita District**OiraseIwate Prefecture*Karumai-History:...

to facilitate the delivery of relief supplies via the city.

External links

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