Specially trained swimmers help launch and recover the WHOI-operated deep-diving submersible Alvin. In the submersible's history, only 36 people with an underwater brand of "the right stuff" have become Alvin pilots. (Mark Spear, Woods Hole Oceanographic Institution)
R/V Atlantis is the only vessel in the U.S. research fleet designed to support the Alvin submersible. (Photo by Amy Nevala, Woods Hole Oceanographic Institution)
Alvin hangs from the stern A-frame of R/V Atlantis, as it is brought back on to the ship following a dive in the Pacific Ocean. (Christopher Knight, Woods Hole Oceanographic Institution)
Deep Submergence Vehicle Alvin
Woods Hole Oceanographic Institution operates the U.S. Navy-owned Deep Submergence Vehicle Alvin for the oceanographic research community. Built in 1964 as the world’s first deep-ocean submersible, Alvin has
made more than 4,200 dives and can reach nearly 63 percent of the
global ocean floor. 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 Titanicin 1986.
Part of the U.S. National Deep Submergence Facility, Alvin carries
two scientists and a pilot as deep as 4,500 meters (about three miles)
and each dive lasts six to ten hours. Using six reversible thrusters, Alvin can
hover, maneuver in rugged topography, or rest on the sea floor. Diving
and surfacing is done by simple gravity and buoyancy—water ballast and
expendable steel weights sink the sub, and that extra weight is dropped
when the researchers need to rise to the surface.
The
sub
is equipped with still and video cameras, and scientists can view
the environment through three 30-centimeter (12-inch) viewports.
Because there is no light in the deep, the submersible must carry
quartz iodide and metal halide lights to illuminate the seafloor. Alvinhas
two robotic arms that can manipulate instruments, and its basket can
carry up to 680 kilograms (1,500 pounds) of tools and seafloor samples.
Through numerous reconstructions and upgrades made over the years, Alvinremains state-of-the-art. (For instance, a new robotic arm was installed in 2006.) The sub is completely
disassembled every three to five years so engineers can inspect every
last bolt, filter, pump, valve, circuit, tube, wire, light, and
battery—all of which have been replaced at least once in the sub’s
lifetime.
The sub is named for Allyn Vine, a WHOI engineer and geophysicist who helped pioneer deep submergence research and technology.
Research Vessel Atlantis
The research vessel (R/V) Atlantisis owned by the U.S.
Navy and operated by the Woods Hole Oceanographic Institution for the
global oceanographic community. It is one of the most sophisticated
research vessels afloat, and it is the only ship specifically outfitted
for launching and servicing the Alvinhuman occupied submersible.
Delivered to Woods Hole in April 1997, Atlantis was built with six science labs
and storage spaces, precision navigation systems, seafloor mapping
sonar, and satellite communications. The ship’s three winches, three
cranes, machine shop, and specialized hangars were specifically designed to support Alvinand
other vehicles of the U.S. National Deep Submergence Facility. The ship
carries a complement of 38 crew members, science technicians, deep
submergence group members, as well as a scientific party of 24 men and
women for as long as 60 days. Because Atlantis is constantly going where Alvinis
needed for exploration, the ship operates in all of the world’s oceans
and is rarely seen in Woods Hole. In recent years, the ship and sub
have spent most of their time exploring underwater volcanoes and
hydrothermal vents in the Pacific Ocean.
Atlantis is the
namesake of WHOI’s first research vessel, a 142-foot, steel-hulled,
ketch-rigged ship that sailed 299 cruises and more than 700,000 miles
for ocean science from 1931 to 1966. The Institution’s flagship and
symbol was the first American ship built specifically for research in
marine biology, marine geology, and physical oceanography.
The space shuttleAtlantis—which will visit the International Space Station again in March--was named for the original WHOI research vessel.
From the Seafloor to the Space Station
