A remotely operated vehicle (ROV) is a free-swimming submersible craft used to perform tasks such as valve operations, hydraulic functions and other general tasks within the subsea oil and gas industry. ROVs can also carry tooling packages for undertaking specific tasks such as pull-in and connection of flexible flowlines and umbilicals, and component replacement.
Underwater divers may be employed in any branch of an armed force, including the navy, army, marines, air force and coast guard. Scope of operations includes: search and recovery, search and rescue, hydrographic survey, explosive ordnance disposal, demolition, underwater engineering, salvage, ships husbandry, reconnaissance, infiltration, sabotage, counterifiltration, underwater combat and security.
A submersible is an underwater vehicle which needs to be transported and supported by a larger watercraft or platform. This distinguishes submersibles from submarines, which are self-supporting and capable of prolonged independent operation at sea.
A diving support vessel is a ship that is used as a floating base for professional diving projects. Basic requirements are the ability to keep station accurately and reliably throughout a diving operation, often in close proximity to drilling or production platforms, for positioning to degrade slowly enough in deteriorating conditions to recover divers without excessive risk, and to carry the necessary support equipment for the mode of diving to be used.
A deep-submergence vehicle (DSV) is a deep-diving crewed submersible that is self-propelled. Several navies operate vehicles that can be accurately described as DSVs. DSVs are commonly divided into two types: research DSVs, which are used for exploration and surveying, and DSRVs, which are intended to be used for rescuing the crew of a sunken navy submarine, clandestine (espionage) missions, or both. DSRVs are equipped with docking chambers to allow personnel ingress and egress via a manhole.
Kaikō was a remotely operated underwater vehicle (ROV) built by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) for exploration of the deep sea. Kaikō was the second of only five vessels ever to reach the bottom of the Challenger Deep, as of 2019. Between 1995 and 2003, this 10.6 ton unmanned submersible conducted more than 250 dives, collecting 350 biological species, some of which could prove to be useful in medical and industrial applications. On 29 May 2003, Kaikō was lost at sea off the coast of Shikoku Island during Typhoon Chan-Hom, when a secondary cable connecting it to its launcher at the ocean surface broke.
AS-28 is a Priz-class deep-submergence rescue vehicle of the Russian Navy, which entered service in 1986. It was designed for submarine rescue operations by the Lazurit Design Bureau in Nizhny Novgorod. It is 13.5 m (44 ft) long, 5.7 m (19 ft) high, and can operate up to a depth of 1,000 m (3,300 ft).
The LR5 is a crewed submersible which was used by the British Royal Navy until 2009 when it was leased to support the Royal Australian Navy. It is designed for retrieving sailors from stranded submarines and is capable of rescuing 16 at a time. The Royal Navy now has the use of the NATO Submarine Rescue System.
A diving chamber is a vessel for human occupation, which may have an entrance that can be sealed to hold an internal pressure significantly higher than ambient pressure, a pressurised gas system to control the internal pressure, and a supply of breathing gas for the occupants.
A deep-submergence rescue vehicle (DSRV) is a type of deep-submergence vehicle used for rescue of downed submarines and clandestine missions. While DSRV is the term most often used by the United States Navy, other nations have different designations for their vehicles.
DSV-4 is a 25-ton, crewed deep-ocean research submersible owned by the United States Navy, now known only by its hull number, not by its former name.
The NATO Submarine Rescue System (NSRS) is a tri-national project to develop an international submarine rescue system. The system provides a rescue capability primarily to the partner nations of France, Norway and the United Kingdom, but also to NATO and allied nations and to any submarine equipped with a suitable mating surface around its hatches.
HMS Reclaim was a deep diving and submarine rescue vessel of the British Royal Navy. She was originally intended to be the King Salvor-class ocean salvage vesselSalverdant and was fitted with specialised equipment including underwater television cameras and sonar and echosounding apparatus. She was also equipped for submarine rescue work.
Salvage diving is the diving work associated with the recovery of all or part of ships, their cargoes, aircraft, and other vehicles and structures which have sunk or fallen into water. In the case of ships it may also refer to repair work done to make an abandoned or distressed but still floating vessel more suitable for towing or propulsion under its own power. The recreational/technical activity known as wreck diving is generally not considered salvage work, though some recovery of artifacts may be done by recreational divers.
HSwMS Belos (A214) is a submarine rescue ship in the Swedish Navy's 1st Submarine flotilla. She carries the Submarine Rescue Vehicle URF. She is also capable of carrying the NATO rescue system NSRS. HSwMS Belos is currently [2017] the largest ship in the Swedish Navy. HMS Belos is traditionally the name of the Swedish navy's submarine rescue vessel and she is the third ship with that name.
Pisces-class submersibles are three-person research deep-submergence vehicles designed and built by Hyco International Hydrodynamics of North Vancouver in British Columbia with a maximum operating depth of 2,000 m (6,560 ft). The vehicles have multiple view ports and sample collecting, environmental sensing, and instrument placement capabilities. The pressure hull has a 7 ft (2.1 m) inside diameter and is made of HY-100 steel with three forward-looking acrylic windows, 6 in (15 cm) in diameter. Designed by Allan Trice, the Pisces series of submersibles were representative of crewed submersibles built in the late 1960s and were proven workhorses in offshore exploration and oceanographic research. Pisces II was the first production model of the design and was completed in 1968, with nine more Pisces submarines built before the manufacturer went out of business in the late 1970s.
The Cheonghaejin class is a submarine rescue ship class of the Republic of Korea Navy. Only one ship has been built in the class, ROKS Cheonghaejin, in 1995. Its operations include rescuing trapped sailors in submarines, naval operation support for submarines, underwater research and mapping support, and recovery of sunk vessels. It is equipped with a deep submergence rescue vehicle (DSRV) that operates up to 500 metres (1,600 ft), and a rescue chamber that holds up to nine people.
Diving support equipment is the equipment used to facilitate a diving operation. It is either not taken into the water during the dive, such as the gas panel and compressor, or is not integral to the actual diving, being there to make the dive easier or safer, such as a surface decompression chamber. Some equipment, like a diving stage, is not easily categorised as diving or support equipment, and may be considered as either.
The Multi-Role Ocean Surveillance Ship (MROSS) is a type of research and surveillance ship in development since 2021 for the United Kingdom's Royal Fleet Auxiliary. The first ship, RFA Proteus, is a commercial ship converted to the role which entered service in October 2023. The second ship is planned as a new build vessel. Both ships are to be used by the RFA to research and protect critical undersea national infrastructure, such as undersea cables and gas pipelines, in both British and international waters.
Submarine rescue is the process of locating a sunk submarine with survivors on board, and bringing the survivors to safety. This may be done by recovering the vessel to the surface first, or by transferring the trapped personnel to a rescue bell or deep-submergence rescue vehicle to bring them to the surface. Submarine rescue may be done at pressures between ambient at depth, and sea level atmospheric pressure, depending on the condition of the distressed vessel and the equipment used for the rescue. Self-rescue of submarine personnel by buoyant free ascent at ambient pressure is considered submarine escape. Survivors may require recompression treatment for decompression illness.
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