Human Occupied Vehicle Alvin
Alvin during its 2014 science verification cruise in the Gulf of Mexico. The submersible has safely transported over 2,500 researchers on more than 4,800 dives to depths of 14,764 feet (4,500 meters). (Photo by Chris Linder, Woods Hole Oceanographic Institution)
WHOI operates the U.S. Navy-owned Deep Submergence Vehicle Alvin for the national oceanographic community. Commissioned in 1964 as one of the world’s first deep-ocean submersibles, Alvin has made more than 4,700 dives.
The sub's most famous exploits include locating a lost hydrogen bomb in the Mediterranean Sea in 1966, exploring the first known hydrothermal vent sites in the 1970s, and surveying the wreck of RMS Titanic in 1986. In addition, the sub has enabled dozens of new discoveries and countless insights into the way that deep sea geology, chemistry, and biology function independently and interact as part of Earth's overall planetary system.
Alvin carries a pilot and two scientists on dives lasting six to ten hours. With seven reversible thrusters, it can hover in the water, maneuver over rugged topography, or rest on the sea floor. The sub is equipped with HD video/still cameras, and scientists can view the environment and sampling equipment through five viewports. Because there is no light below about 100 meters, the submersible carries high-intensity LED lights to illuminate the water column and seafloor. Alvin has two robotic arms that can manipulate instruments, and its basket can return up to 400 pounds of seafloor samples to the surface.
Though it is the world’s oldest research submersible, Alvin remains state-of-the-art as a result of numerous overhauls and upgrades made over its lifetime. The most recent, completed in 2013, saw the installation of a new, larger personnel sphere with an ergonomic interior; five viewports (instead of the previous three) to improve visibility and provide overlapping fields of view; new lighting and high-definition imaging systems; new syntactic foam providing additional buoyancy; and an improved command-and-control system. Alvin is also completely disassembled every three to five years so engineers can inspect every individual component that makes up the submersible.
Alvin is named for Allyn Vine, a WHOI engineer and geophysicist who helped pioneer deep submergence research and technology.