Marine salvage

In contract salvage the owner of the property and salvor enter into a salvage contract prior to the commencement of salvage operations and the amount that the salvor is paid is determined by the contract. This can be a fixed amount, based on a "time and materials" basis, or any other terms that both parties agree to. The contract may also state that payment is only due if the salvage operation is successful (a.k.a. "No Cure, No Pay"),[3] or that payment is due even if the operation is not successful. By far the commonest single form of salvage contract internationally is Lloyd's Standard Form of Salvage Agreement (2011, superseded in 2020), an English law arbitration agreement administered by the Council of Lloyd's, London.[4][5][6]

In the United States, in pure salvage (also called "merit salvage"), there is no contract between the owner of the goods and the salvor. The relationship is one which is implied by law. The salvor of property under pure salvage must bring his claim for salvage in a court which has jurisdiction, and this will award salvage based upon the "merit" of the service and the value of the salvaged property.

Pure salvage claims are divided into "high-order" and "low-order" salvage. In high-order salvage, the salvor exposes himself and his crew to the risk of injury and loss or damage to his equipment in order to salvage the property that is in peril. Examples of high-order salvage are boarding a sinking ship in heavy weather, boarding a ship which is on fire, raising a ship, plane, or other sunken property, or towing a ship which is in the surf away from the shore. Low-order salvage occurs where the salvor is exposed to little or no personal risk. Examples of low-order salvage include towing another vessel in calm seas, supplying a vessel with fuel, or pulling a vessel off a sand bar. Salvors performing high order salvage receive substantially greater salvage award than those performing low order salvage.

In order for a claim to be awarded three requirements must be met: The property must be in peril, the services must be rendered voluntarily (no duty to act), and finally the salvage must be successful in whole or in part.

There are several factors that would be considered by a court in establishing the amount of the salvor's award. Some of these include the difficulty of the operation, the risk involved to the salvor, the value of the property saved, the degree of danger to which the property was exposed, and the potential environmental impacts. It would be a rare case in which the salvage award would be greater than 50 percent of the value of the property salvaged. More commonly, salvage awards amount to 10 percent to 25 percent of the value of the property.

Private boat owners, to protect themselves from salvage laws in the event of a rescue, would be wise to clarify with their rescuer if the operation is to be considered salvage, or simply assistance towing. If this is not done, the boat owner may be shocked to discover that the rescuer may be eligible for a substantial salvage award, and a lien may be placed on the vessel if it is not paid.

USNS Grapple, an example of a modern naval rescue salvage ship

Several navies have Rescue Salvage vessels which are to support their fleet and to come to the aid of vessels in distress. In addition they may have Deep Salvage Units. A DSU (salvage) is a unit attached to the US Navy.[7]

When vessels are lost in an unknown area, or are not protected, a potential salvor might discover and plunder the wreck without knowledge of the wreck's owner. Salvaging a foreign navy's vessel is against international law.[8] World War II-era shipwrecks near Indonesia, where most of the water is shallower than 80 metres (260 ft) are threatened by scavenging for low-background steel for use in medical and scientific equipment.[9]

At the height of the Cold War the United States raised a portion of Soviet submarine K-129 in the Western Pacific Ocean. The CIA, who conducted the salvage under the guise of "mining the seafloor for manganese nodules" with a commercial vessel, spent over $800 million (1974 dollars) on the clandestine operation now known as Project Azorian.

A salvage survey is done to get information on the state of the vessel and the site which will be useful for planning the salvage operation.[13]^{: Ch. 2}

There is usually an initial or preliminary survey, followd by detailed surveys of topsides, interior, and underwater hull, and a hydrographic survey of the site, as applicable. A safety survey and risk assessment is part of these surveys, which are continuously updated as part of the operation, as conditions change, and the operational plans are adapted to suit the changing circumstances.[13]^{: Ch. 2}

It is usually preferable to refloat a vessel so that it cam be taken to a suitable venue for repair or scrapping, but his is not always reasonably practicable.

There are the basic aspects to refloating a stranded ship: Its position must be stabilised so that it is not damaged further by ground contact forces. Ground reactions must then be reduced to a level where the available pulling force can move the vessel off the ground without doing too much further damage, then the vessel is pulled off and moved into deeper water, where it floats free of the ground.[13]^{: Ch. 8}

Stabilising the vessel implies ensuring that it will not capsize due to insufficient static stability. This may require reducing free surfaces, lowering the centre of gravity, and/or physically restraining listing by pontoons fastened alongside to increase the waterplane area, or applying righting forces to counter upsetting forces. Physically constraining the vessel from capsizing by holding one end on the bottom while refloating the other end by slewing it into deeper water can be effective.[13]^{: Ch. 8}

Several approaches are available for reducing ground reaction forces:

Weight management is the movement of weight around the vessel. Weight removal from near the area where the vessel is resting on the ground reduces ground reaction, while removing weight further away may increase ground reaction. It may be useful to keep a high ground reaction to avoid the vessel running further aground until ready to haul it off. All weight shifts should be done taking the effects on stability into consideration.[13]^{: Ch. 8}

Buoyancy can be increased by dewatering flooded volumes either by pumping if the compartment is not holed below the waterplane, or by blowing down with compressed air if the compartment can be sealed above the waterplane. A third method of displacing the water with buoyant material is sometimes possible.[13]^{: Ch. 8}

Ground removal from under the contact area is sometimes possible. Removal of ground allows the ship to sink deeper and regain some of its buoyancy provided it does not flood further. It may be necessary to remove ground in a channel allowing the vessel to be floated to seaward to deep water. Ground removal depends to a large extent on the nature of the ground. Sand and firm clay can be removed fairly easily and the channel will be reasonably stable in the short term. Hard bottoms are difficult to remove, and soft materials may refill quickly. If the vessel is resting on penetrating rocks they must be removed to allow the vessel to be moved, but their removal does not generally reduce ground reaction by much.[13]^{: Ch. 8}

Scouring is the use of water flow to remove ground from around a ship. Currents may be produced by the propeller wash of tugs alongside, the ship's own propeller wash, or jetting pumps, and is most effective in sand or mud. Sometimes natural currents can be redirected to scour usefully. Dredging may be used to move large quantities of loose or soft material from around and under a vessel and to dig channels to deep water. The equipment used for dredging depends on the seabed material and topography, access to the casualty, the situation of the casualty, and the dredging equipment available.[13]^{: Ch. 8}

• Lifting
• Temporary reductions

Underwater patching is almost always done by divers. As much patch fabrication and rigging as possible should be done out of the water to minimise diving time. Small leaks are generally sealed off and made watertight by wooden plugs and wedges, small wooden patches and concrete boxes, small steel plate patches or combinations of these, caulked and sometimes additionally sealed with epoxy resin or fibre-reinforced resins. Small steel patches for minor leaks are usually fitted with gasket material to seal against the damaged hull. Major patching is characterized by extensive diving work and includes detailed underwater surveys, measurements, and major underwater cutting and welding operations to prepare and fit the patch.[13]^: Ch.10

When all or part of the main deck of a sunken ship is submerged, flooded spaces cannot be dewatered until all openings are sealed or the effective freeboard is extended above the high water level. In salvage, one method of doing this is to build a temporary watertight extension of the entire hull of the ship, or the space to be dewatered, to the surface. This watertight extension is a cofferdam. Although they are temporary structures, cofferdams have to be strongly built, heavily stiffened, and reinforced to withstand the hydrostatic and other loads that they will have to withstand. Large cofferdams, are normally confined to harbor operations.[13]^: Ch.10

Complete cofferdams cover most or all of the sunken vessel and are equivalent to extensions of the ship's sides to above the water surface.[13]^: Ch.10

Partial cofferdams are constructed around moderate-sized openings or areas such as a cargo hatch or small deckhouse. They can often usually can be prefabricated and installed as a unit, or prefabricated panels can be joined during erection. When partial cofferdams are used, it may be necessary to compensate for hydrostatic pressure on the deck by shoring the decks. With both complete and partial cofferdams, there is usually a large free surface in the spaces being pumped.[13]^: Ch.10

Small cofferdams are used for pumping or to allow salvors access to spaces that are covered by water at some stage of the tide. They are usually prefabricated and fitted around minor openings.[13]^: Ch.10

Diving work on cofferdams often involves clearing obstructions, fitting, and fastening, including underwater welding, and where necessary, caulking, bracing and shoring the adjacent structure.[13]^: Ch.10

Removal of water from flooded parts of the vessel is done to increase buoyancy by removing weight. The effect on stability is variable depending on the free surface in each compartment, and the effect on the position of the centre of gravity. Dewatering may be done by pumping the water out and allowing atmospheric pressure air to replace it through vents, in which case the external hydrostatic pressure loads may require shoring and bracing, or by sealing the compartment and blowing out the water using compressed air, which puts internal pressure loads on the structure which depend on the pressure needed to expel the water.[13]^{: Ch. 11}

Tugs and ground tackle are commonly used in salvage. Tugs are attached to the vessel by a towline, and develop pulling forces with their engines and propellers. Salvage ground tackle is a system of anchors, ground leg,[14] and hauling gear[15] rigged to pullers, purchases,[16] or winches, on a platform, which may be the stranded ship, a salvage ship, a barge, or the shore. The total pulling force may be developed by a combination of ground tackle and tugs, set up to suit the job at hand.[13]^{: Ch. 8}

Most salvage operations involve some form of lifting, from handling materials and equipment to lifting whole shops from the seabed. Several methods are commonly used. External lifting is often a practical alternative to recovering buorncy, and has some advantages in that it reduces the complex underwater work of making the vessel watertight relatively straightforward rigging, which usually requires less preparation time at depth and inside a sunk vessel.[13]^{: Ch. 13}

External lifting usually allows good lift control because the lifting units can be synchronized to achieve the desired lift throughout the operation, it can provide more transverse and longitudinal stability compared to recovery of buoyancy, and is usually quicker.[13]^{: Ch. 13}

There are three categories of external lift: Immersed bouyant lifts, tidal lifts and mechanical lifts.[13]^{: Ch. 13}

Inflatable lift bags and rigid steel pontoons have been consistently useful as submersible buoyant lifting devices for salvage work.[13]^{: Ch. 13}

Wrecking in place is also called piecemeal demolition, and is the dismantling of the whole or parts of a wreck in situ, usually when it is not possible or economically viable to salvage it, and it is a navigational hazard or must be removed for some other reason. Removal and disposal of the ship's contents, such as cargo, stores, and equipment may be included.[13]^{: Ch. 14}

The usual methods for wrecking in place are manual flame cutting by divers and surface workers, mechanical demolition using heavy lift cranes, explosive sectioning, dispersal, or flattening, and burial or settling by hydraulic dredging.[13]^{: Ch. 14}

Underwater search is a basic aspect of deep water salvage operations, as before an object can be recovered, it must first be found, inspected and identified, and the position recorded so that it can be returned to when necessary. Deep water searches are often complex and difficult, and good planning and preparation, and precise execution of the plan increase the chances of success.[17]

The era of modern salvage operations was inaugurated with the development of the first surface supplied diving helmets by the inventors, Charles and John Deane and Augustus Siebe, in the 1830s. HMS Royal George, a 100-gun first-rate ship of the line of the Royal Navy, sank undergoing routine maintenance work in 1782, and the Deane brothers were commissioned to perform salvage work on the wreck. Using their new air-pumped diving helmets, they managed to recover about two dozen cannons.

Following on from this success, Colonel of the Royal Engineers Charles Pasley commenced the first large scale salvage operation in 1839. His plan was to break up the wreck of Royal George with gunpowder charges and then salvage as much as possible using divers.

The sinking of Royal George

Pasley's diving salvage operation set many diving milestones, including the first recorded use of the buddy system in diving, when he ordered that his divers operate in pairs. In addition, the first emergency swimming ascent was made by a diver after his air line became tangled and he had to cut it free. A less fortunate milestone was the first medical account of a helmet squeeze suffered by a Private Williams: the early diving helmets used had no non-return valves on the breathing air supply hose; this meant that if a hose became severed near or above the surface, the high-pressure air around the diver's head rapidly escaped from the helmet leaving a large pressure difference between the water and the suit and helmet interior that tended to force the diver into rigid interior of the helmet. At the British Association for the Advancement of Science meeting in 1842, Sir John Richardson described the diving apparatus and treatment of diver Roderick Cameron following an injury that occurred on 14 October 1841 during the salvage operations.[19]

Pasley recovered 12 more guns in 1839, 11 more in 1840, and 6 in 1841. In 1842 he recovered only one iron 12-pounder because he ordered the divers to concentrate on removing the hull timbers rather than search for guns. Other items recovered, in 1840, included the surgeon's brass instruments, silk garments of satin weave 'of which the silk was perfect', and pieces of leather; but no woollen clothing.[20] By 1843 the whole of the keel and the bottom timbers had been raised and the site was declared clear.[21]

The largest marine salvage operation on record was the raising of the German High Seas Fleet which was scuttled at Scapa Flow in 1919. Between 1922 and 1939, 45 of the 52 warships sunk, including six battleships, five battlecruisers, five cruisers and 32 destroyers were raised from depths of up to 45 metres, primarily by Cox & Danks Ltd & Metal Industries Ltd, and broken up for scrap.

The harbor clearance and ship recovery after the attack on Pearl Harbor. USS California and USS West Virginia, resting on the bottom of Pearl Harbor on 7 December 1941, were refloated and repaired.[22] They were key participants in the Battle of Surigao Strait in October 1944.[23]

In 1943–44 the Great Lakes salvage engineer, Captain John Roen, did what was considered financially impossible and salvaged SS George M. Humphrey, which sank in a collision in 23 metres (77 ft) of water in the Straits of Mackinac, by first removing the ore it was carrying and then using two vessels on each side of the underwater wreck, with cables that "walked" George M. Humphrey in stages underwater to shallower water where it was then pumped out and re-floated and towed out. Some of the techniques developed by Roen for the salvage of George M. Humphrey established methods which became new standards for future salvages, where before many wrecks were considered too heavy and large to salvage.[24]

The Swedish 17th-century warship Vasa was raised in April 1961. She had lain on the bottom of Stockholm harbor since capsizing on her maiden voyage in 1628.

The raising and subsequent conservation of Mary Rose, the flagship of the navy of King Henry VIII, which sank in 1545 in the Solent, North of the Isle of Wight. As with Vasa, the salvage of Mary Rose in 1982 was an operation of immense complexity and was a major achievement in marine archaeology. The remains of the ship, together with recovered weapons, sailing equipment and crew's personal effects are now on display at Portsmouth Historic Dockyard and the nearby Mary Rose Museum.

In 1968 Shipwrecks Inc., headed by E. Lee Spence, was granted South Carolina State Salvage License No. 1 to salvage the wreck of the American Civil War blockade runner SS Georgiana under that state's new underwater antiquities act, which had been drafted and passed at the instigation of Spence, who had discovered the wreck in 1965. Spence's work on the wreck was some of the first underwater archaeology done in the United States.[25][26] Shipwrecks Inc. raised over 1,000,000 individual artifacts, conservatively valued at over $12,000,000. The artifacts ranged from tiny brass sewing pins and glass buttons to heavy iron cannons and included such things as cannonballs; bullets; bottles; pottery; carved bone toothbrushes; pencils; match cases; and Wedgwood china.[27]

In 1974 the U.S. CIA attempted to recover the sunken Soviet Golf-class submarine K-129 in the secret and expensive intelligence operation Project Azorian. The attempt was only partially successful.

Nuestra Señora de Atocha was discovered in 1985 with recovered gold and other artifacts worth an estimated US$400 million.[28]

The SS Central America, which sank in 1857 carrying 14,000 kilograms (30,000 lb) of gold, was discovered in 1988. Salvage efforts remain incomplete.

The search for the wreckage and flight data recorders of South African Airways Flight 295 at 4,900 metres (16,000 ft).[29]

On 12 August 2000, the Russian Oscar-class submarine Kursk sank in the Barents Sea following an internal explosion, leading to the death of 118 sailors and officers. A portion of the destroyed submarine was raised to the surface in late 2001 to recover the bodies and eliminate the hazard from Kursk's two nuclear reactors.

USS Cole being carried by MV Blue Marlin

USS Cole was severely damaged in October 2000 by terrorists while it was harbored in the Yemeni port of Aden. It was rescued, salvaged, and repaired to serve again.

In July 2002, HMS Nottingham suffered serious damage due to a navigational error, striking Wolf Rock near Lord Howe Island. She was towed, stern first to Newcastle, New South Wales in August 2002 for minor repairs and was consequently returned to the United Kingdom aboard the heavy lifting vessel MV Swan.

In July 2006, the Japanese car carrier Cougar Ace, carrying 4,700 Mazda cars and Isuzu trucks bound for the North American market, was traveling from Japan to Vancouver, British Columbia, when it stranded in the Pacific Ocean. The ship's condition quickly began to deteriorate as it took on water. The salvage team worked for 24 days to try and save the vessel and its cargo.[30]

In May 2007, Odyssey Marine Exploration undertook the Black Swan Project and recovered an estimated US$500 million in silver and gold coins from a shipwreck in the Atlantic Ocean.[31] However, the wreck and its contents were claimed by the Spanish government.[32] A legal dispute through United States Federal Courts was resolved in February 2012, when it was reported that U.S. Magistrate Judge Mark Pizzo had ordered Odyssey to return the coins to Spain by 24 February 2012 for dispersal to museums, not to heirs. The Supreme Court declined to stay this order and Odyssey has agreed to abide by the decision.[33]

In 2021, Phoenix International Holdings, Inc. (Phoenix), under the direction of the U.S. Navy's Supervisor of Salvage and Diving (SUPSALV), located and recovered the fuselage of a downed MH-60 Seahawk helicopter in the Philippine Sea from a record breaking depth of 5,814 metres (19,075 ft) beneath the surface. This is 81 metres (266 ft) deeper than the previous salvage record, also set by Phoenix and SUPSALV during the recovery of a C-2 Greyhound aircraft in 2019. [34]