Research Vessels: Submersibles - ALVIN
A standard dive on ALVIN lasts 6 to 10 hours.
(Courtesy of WHOI)
Submersibles are a great scientific tool to help
researchers explore the ocean depths. They are small submarines
that can maneuver underwater easier than larger submarines. Submersibles
are equiped with viewports (windows), searchlights, mechanical arms,
cameras and scientific instruments that enable seeing and recording
data from underwater vehicles.
Perhaps ONR's most famous submersible is ALVIN,
a three-person deep submergence vessel (DSV). Among some of its most
memorable missions are discovery of deep-sea hydrothermal
vents and recovery of a missing H-bomb. ONR funded the development
of ALVIN in 1962 for almost $10 million.
ALVIN was named for Allyn Vine, a Woods
Hole Oceanographic Institution (WHOI) oceanographer. ALVIN was
built with ONR money and is now used by WHOI scientists.
In 1966, the two-year-old ALVIN was presented with its first difficult
task. A 20 mega-ton H-bomb was lost off the Spanish Coast in the
Mediterranean Sea after two planes collided. Three other subs, including
the U.S. Navy's Deep Jeep, newspaper publisher John H. Perry Jr.'s
PC-3B and J. Louis Reynold's Aluminaut, also participated in the
search for the missing bomb. Despite the competition, it was ALVIN
that located the bomb resting below 2,500 feet of water.
Alvin being lowered into the water.
(Courtesy of WHOI)
Then, in August of 1968, tragedy struck. ALVIN was lost. As the
DSV was being placed into the water a few hundred miles off Cape
Cod, a cable holding it up broke. Luckily, the men inside were able
to escape through the open hatch before ALVIN sank 5,500 feet to
the bottom. After spending 11 months on the ocean floor, ALVIN was
located by sonar. Aluminaut placed a hook
inside ALVIN's open hatch and towed it to the surface. ALVIN was
back in shape and diving again before the end of 1970.
When ALVIN was first built, its pressure hull was made
with steel, and it could only dive 6,000 feet. In 1973, ALVIN was
rebuilt with a titanium hull making it possible to reach depths of
13,124 feet (4,000 meters).
ALVIN has three video cameras, two still cameras, 12
lights and two hydraulic robot arms. A basket found on the front of
the submersible carries scientific instruments.
Today, ALVIN makes between 150 and 200 dives each year and has more
than 3,200 dives on record. Its support ship, required to tote it
to study sites and provide support, is the catamaran R/V Atlantis
II, which holds up to 27 crew members, 19 scientists and 9 ALVIN