Alvin (
DSV-2) is a 16-ton, manned deep-ocean research
submersible owned by the
United States Navy and operated by the
Woods Hole Oceanographic Institution (WHOI) in
Woods Hole, Massachusetts. The craft was built by
General Mills' Electronics Group in the same factory used to manufacture breakfast cereal-producing machinery in
Minneapolis, Minnesota. Named to honor the prime mover and creative inspiration for the vehicle,
Allyn Vine,
Alvin was commissioned on 5 June 1964.
The submersible is launched from the deep submergence support vessel
Atlantis, which is also owned by the U.S. Navy and operated by WHOI. The submersible has taken 12,000 people on over 4,000 dives to observe the lifeforms that must cope with super-pressures and move about in total darkness. It is said that research conducted by
Alvin has been featured in nearly 2,000 scientific papers.
Alvin was designed as a replacement for
bathyscaphes and other less maneuverable
oceanographic vehicles. Its more nimble design was made possible in part by the development of
syntactic foam, which is buoyant and yet strong enough to serve as a structural material at great depths. The three-person vessel allows for two scientists and one pilot to dive for up to nine hours at 4500 meters (15,000 ft). The submersible features two robotic arms and can be fitted with mission-specific sampling and experimental gear. The hatch of the vessel is 0.6 meters (two feet) thick, and held in place by the pressure of the water above it (it is tapered, narrower inward).
History
Early career
Alvin, first of its class of
Deep Submergence Vehicle (DSV), was built to dive to 2440 meters (8000 ft). Each of the
Alvin-class DSVs have different depth capabilities. However
Alvin is the only one seconded to the
National Oceanic and Atmospheric Administration (NOAA), with the others staying with the
United States Navy. On 17 March 1966,
Alvin was used to locate a submerged 1.45-megaton
hydrogen bomb lost in a
United States Air Force midair accident over
Palomares,
Spain. The bomb, found resting nearly 910 meters (3000 ft) deep, was raised intact on 7 April.
Sinking
The
Alvin, aboard the NOAA tender ship
Lulu, was lost as it was being transported in October 1968. The
Lulu, a vessel created from a pair of decommissioned US Navy
pontoons with a support structure added on, carried
Alvin on a steel cable. The cable snapped with three crewmembers aboard and the hatch open. Situated between the pontoons with no deck underneath, the
Alvin hit the water and rapidly started to sink. The three crewmembers managed to escape, but the sub sank in 1500 meters (5000 ft) of water.
Ten months later, in September 1969, the
Aluminaut, another US Navy DSV owned by
Reynolds Metals Aluminum Company, secured a line on the
Alvin, and it was hauled up. It was so intact that lunches left on board were soggy but edible. This incident led to a more comprehensive understanding that near-freezing temperatures and the lack of decaying oxygen at depth aided preservation. Notwithstanding the preserved food aboard, the
Alvin required a major overhaul after the incident.
Post-sinking career
In 1973, Alvin's pressure hull was replaced by a newer titanium pressure hull. The new hull extended the submersible's maximum depth to about 4500 meters (15,000 ft).
Black smokers
In 1977, during an expedition led by
Robert Ballard and sponsored by the
National Oceanic and Atmospheric Administration (NOAA),
Alvin discovered and documented the existence of
black smokers around the
Galapagos Islands. Existing at a depth of more than 2000 meters, black smokers emit a strong flow of black, smoky water, superheated to over 400 °
C (750 °
F). Alvin was able to sample the water from a black smoker. Alvin discovered that the
pH was roughly 2.8.
Exploration of RMS Titanic
Most famously,
Alvin was involved in the exploration of the wreckage of
RMS Titanic in 1986. Launched from her support ship
R/V Atlantis II, she carried Dr.
Robert Ballard and two companions to the wreckage of the great liner. RMS
Titanic sank in 1912 after striking an
iceberg while crossing the North Atlantic Ocean on her
maiden voyage.
Alvin, accompanied by a small
remotely operated vehicle (ROV) named
Jason Jr., was able to conduct detailed photographic surveys and inspections of the
Titanic's wreckage. Many of the photographs of the expedition have been published in the magazine of the
National Geographic Society which was a major sponsor of the expedition.
Of note, the
Woods Hole Oceanographic Institute team involved in the Titanic expedition also managed to locate the wreck of the
USS Scorpion (SSN-589), a nuclear armed Skipjack class submarine which sank off the coast of the Azores in 1968. The
Alvin was able to obtain photographic and other environmental monitoring data from the remains of the Scorpion.
Recent overhauls
Over the years, the
Alvin has undergone many overhauls to improve its equipment and extend its lifetime. The most recent overhaul was during 2001 in which, among other equipment, motor controllers and computer systems were added. The current Alvin is the same as the original vessel in name and general design only. All components of the vessel including the frame and personnel sphere have been replaced at least once. Alvin is completely disassembled every three to five years for a complete inspection. A new robotic arm was added in 2006.
Current work
In June 2008 construction started on a stronger and slightly larger personnel sphere which may be used to upgrade Alvin (for use from 2011), before being used in an entirely new vehicle. The new sphere will have five view ports (instead of the current three) and is designed for depths of over 6,000 metres (Alvin = 4,500 metres).
A possible replacement
On 6 August 2004, the
National Science Foundation announced the creation of a new Human Occupied Vehicle (HOV) to replace the aging
Alvin. The new vehicle is being designed to dive deeper up to 6500 meters (21,000 ft) as opposed to Alvin's 4500 meters and use new scientific equipment. The personnel sphere will be larger, and it is expected that the battery capacity will be greatly increased enabling longer bottom times. The new deep sea submarine is in the preliminary manufacturing phases and is expected to be completed as early as the end of 2011. Some components of the current Alvin are anticipated to be used in the new Alvin replacement vehicle. Due to export laws, the vehicle cannot be sold to parties outside of the United States. The fate of the Alvin when this new submersible arrives is unknown, but due to the limited market for sale and stripping of components for use on the new vehicle, it will likely be placed in a museum.
Lockheed Martin is designing the Alvin replacement vehicle as a nonclassified project and classing the vehicle to
American Bureau of Shipping Rules.
Contrary to a
BBC article published in October 2004 , the
Alvin has not yet been retired from service.
Operation
Alvin uses four 208-pound steel weights (~1.7 cubic feet of steel) to provide negative buoyancy for the trip to the ocean floor.
Alvin contains a ballast and trim system, but the steel weights allow deep dives to be achieved more rapidly. These weights are jettisoned on each dive and left at the bottom.
The DSV ALVIN on the fantail (stern) of the
R/V Atlantis following a dive. On the right side of the photograph the A-frame crane can be seen that lowers the ALVIN into the water and on the left, the ALVIN's hangar.
See also
Alvin class DSV
Other deep submergence vehicles
