The Benthoscope was a deep sea submersible designed by Otis Barton after the Second World War. He hired the Watson-Stillman Company, who had earlier constructed his and William Beebe's bathysphere to produce the new design of deep diving vessel, which was named from the Greek benthos , meaning "bottom".
The Benthoscope was essentially similar to the bathysphere, but was built to withstand higher pressures, with a crush depth of 10,000 feet (3,000 m). Its internal diameter was 4.5 feet (1.4 m), and its wall thickness was 1.75 inches (44 mm). It weighed 7 short tons (6,400 kg), an increase in weight of 1,600 pounds (730 kg) over the bathysphere. Two windows of fused quartz were installed, one facing straight ahead and the other diagonally down. Other arrangements followed the bathysphere, with oxygen supplied from cylinders, and calcium chloride and soda lime used to absorb moisture and CO2 respectively.
In August 1949, Barton established a new world depth record with a solo descent to 4,500 feet (1,400 m), which remains the deepest dive by a submersible suspended by a cable.
The Benthoscope is now on display in front of the Los Angeles Maritime Museum in San Pedro, California.
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.
A bathyscaphe is a free-diving, self-propelled deep-sea submersible, consisting of a crew cabin similar to a Bathysphere, but suspended below a float rather than from a surface cable, as in the classic Bathysphere design.
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 bell is a rigid chamber used to transport divers from the surface to depth and back in open water, usually for the purpose of performing underwater work. The most common types are the open-bottomed wet bell and the closed bell, which can maintain an internal pressure greater than the external ambient. Diving bells are usually suspended by a cable, and lifted and lowered by a winch from a surface support platform. Unlike a submersible, the diving bell is not designed to move under the control of its occupants, or to operate independently of its launch and recovery system.
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.
An atmospheric diving suit (ADS) is a small one-person articulated submersible which resembles a suit of armour, with elaborate pressure joints to allow articulation while maintaining an internal pressure of one atmosphere. An ADS can enable diving at depths of up to 2,300 feet (700 m) for many hours by eliminating the majority of significant physiological dangers associated with deep diving. The occupant of an ADS does not need to decompress, and there is no need for special breathing gas mixtures, so there is little danger of decompression sickness or nitrogen narcosis when the ADS is functioning properly. An ADS can permit less skilled swimmers to complete deep dives, albeit at the expense of dexterity.
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.
Underwater habitats are underwater structures in which people can live for extended periods and carry out most of the basic human functions of a 24-hour day, such as working, resting, eating, attending to personal hygiene, and sleeping. In this context, 'habitat' is generally used in a narrow sense to mean the interior and immediate exterior of the structure and its fixtures, but not its surrounding marine environment. Most early underwater habitats lacked regenerative systems for air, water, food, electricity, and other resources. However, some underwater habitats allow for these resources to be delivered using pipes, or generated within the habitat, rather than manually delivered.
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.
The Deep Drone is a submersible remotely operated vehicle designed for mid-water salvage for the United States Navy. One vehicle is based in Largo, Maryland, under the command of The U.S. Navy Supervisor of Salvage and Diving (SUPSALV), it is maintained and operated by Phoenix International Inc.. The vehicle is capable of operating at a depth up to 8000 feet as reflected in its full name: "The Deep Drone 8000". The vehicle has a target locating sonar and two tool manipulators capable of working with tools and attaching rigging.
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.
The Bathysphere was a unique spherical deep-sea submersible which was unpowered and lowered into the ocean on a cable, and was used to conduct a series of dives off the coast of Bermuda from 1930 to 1934. The Bathysphere was designed in 1928 and 1929 by the American engineer Otis Barton, to be used by the naturalist William Beebe for studying undersea wildlife. Beebe and Barton conducted dives in the Bathysphere together, marking the first time that a marine biologist observed deep-sea animals in their native environment. Their dives set several consecutive world records for the deepest dive ever performed by a human. The record set by the deepest of these, to a depth of 3,028 ft (923 m) on August 15, 1934, lasted until it was broken by Barton in 1949 in a vessel called Benthoscope.
Deep-sea exploration is the investigation of physical, chemical, and biological conditions on the ocean waters and sea bed beyond the continental shelf, for scientific or commercial purposes. Deep-sea exploration is an aspect of underwater exploration and is considered a relatively recent human activity compared to the other areas of geophysical research, as the deeper depths of the sea have been investigated only during comparatively recent years. The ocean depths still remain a largely unexplored part of the Earth, and form a relatively undiscovered domain.
The McCann Submarine Rescue Chamber is a device for rescuing submariners from a submarine that is unable to surface.
ABISMO is a remotely operated underwater vehicle (ROV) built by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) for exploration of the deep sea. It is the only remaining ROV rated to 11,000-meters, ABISMO is intended to be the permanent replacement for Kaikō, a ROV that was lost at sea in 2003.
Deep Diver was the name of a deep-sea scientific research submersible designed by Edwin Albert Link. Deep Diver was the first small submersible designed for lockout diving, allowing divers to leave and enter the craft while underwater. It was first launched in January 1966.
The Johnson Sea Link accident was a June 1973 incident that claimed the lives of two divers. During a seemingly routine dive off Key West, the submersible Johnson Sea Link was trapped for over 24 hours in the wreckage of the destroyer USS Fred T. Berry, which had been sunk to create an artificial reef. Although the submersible was eventually recovered by the rescue vessel A.B. Wood II, two of the four occupants died of carbon dioxide poisoning: 31-year-old Edwin Clayton Link and 51-year-old diver Albert Dennison Stover. The submersible's pilot, Archibald "Jock" Menzies, and ichthyologist Robert Meek survived. Over the next two years, Edwin Link designed an unmanned Cabled Observation and Rescue Device (CORD) that could free a trapped submersible.
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.