Alvin (DSV-2) is a crewed deep-ocean research submersible owned by the United States Navy and operated by the Woods Hole Oceanographic Institution (WHOI) in Woods Hole, Massachusetts. The original vehicle was built by General Mills' Electronics Group in Minneapolis, Minnesota. Named to honor the prime mover and creative inspiration for the vehicle, Allyn Vine, Alvin was commissioned on June 5, 1964. The submersible is launched from the deep submergence support vessel RV Atlantis (AGOR-25), which is also owned by the U.S. Navy and operated by WHOI. The submersible has made more than 5,200 dives, carrying two scientists and a pilot, observing the lifeforms that must cope with super-pressures and move about in total darkness, as well as exploring the wreck of Titanic. Research conducted by Alvin has been featured in nearly 2,000 scientific papers.
The Deep Submergence Insignia is a uniform breast pin worn by officers, both men and a few women of the United States Navy's submarine service who are qualified in submarines and have completed one year of regular assignment to a Manned or Unmanned Deep Submersible. The badge was first approved on 6 April 1981.
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.
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).
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.
DSRV-2Avalon was a Mystic-class deep-submergence rescue vehicle rated to dive up to 5,000 feet (1,500 m) to rescue submarine crews trapped deep under the sea. The submarine was acquired in response to the loss of the USS Thresher, so that the Navy would have a way to rescue trapped submarine crews.
Turtle (DSV-3) was a 16-ton, crewed deep-ocean research submersible owned by the United States Navy. It is sister to Alvin (DSV-2) and Sea Cliff (DSV-4).
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.
DSRV-1Mystic is a deep-submergence rescue vehicle that is rated to dive up to 5,000 feet. It was built by Lockheed for the US Navy at a construction cost of $41 million and launched 24 January 1970. It was declared fully operational in 1977 and named Mystic.
The third USS Pigeon (ASR–21) was the lead ship of her class of submarine rescue ships. Laid down on 17 July 1968 by the Alabama Dry Dock and Shipbuilding Co., Mobile, Alabama, the ship was launched on 13 August 1969, sponsored by Mrs. Allen M. Shinn, wife of Vice Admiral Shinn, Commander Naval Air Force, U.S. Pacific Fleet, and commissioned on 28 April 1973. She was a sister ship to USS Ortolan (ASR-22).
The United States Naval Undersea Museum is a naval museum located at Keyport, Washington. It is one of the 10 Navy museums that are operated by the Naval History & Heritage Command. It sits next to a branch of the Naval Undersea Warfare Center.
The McCann Submarine Rescue Chamber is a device for rescuing submariners from a submarine that is unable to surface.
A submarine rescue ship is a surface support ship for submarine rescue and deep-sea salvage operations. Methods employed include the McCann Rescue Chamber, deep-submergence rescue vehicles (DSRV's) and diving operations.
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.
URF is the Royal Swedish Navy’s Submarine Rescue Vessel.
Type 926 submarine support ship with NATO reporting name Dalao is a class of submarine rescue and supply ship developed by China for the People's Liberation Army Navy (PLAN), and as of mid-2014, a total of three are in service. This ship is capable of both replenishing submarines and rescuing submariners in distress.
JS Chiyoda was a submarine rescue ship of the Japan Maritime Self-Defense Force.
DSV-5, ex-NEMO, was a submersible used by the United States Navy between 1970 and 1986 to oversee and observe undersea construction work. NEMO had a spherical transparent acrylic hull, which gave occupants panoramic vision. NEMO was the first submersible with a hull made entirely out of transparent acrylic (Plexiglass), and much of her career was spent testing this hull design. NEMO was found to be an effective observation platform, despite not being able to hover in place, and acrylic-hulled submersibles have continued to be built and operated in the United States. NEMO is considered part of the Alvin class of Deep Submergence Vehicles despite bearing little resemblance to the other subs of the class. NEMO was transferred to "other government agencies" in 1986 and retired from government service in 2011. It was then given to the U.S. Navy Seabee Museum, where it remains on display.
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.
The Nistar class is a series of two diving support vessels being built by Hindustan Shipyard (HSL) for the Indian Navy. The deal was signed on 20 September 2018 with the delivery of the ships is scheduled to commence from July 2023. The primary role of the vessels to support the Indian Navy's submarine fleet and meet various operational requirements such as submarine rescue, deep sea diving operations, sustained patrolling, non combatant evacuation operations and search and rescue (SAR).
United States Navy 
