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Artist's rendition of the replacement human-occupied vehicle (HOV) for ALVIN.
Credit: Woods Hole Oceanographic Institution
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This animation describes the characteristics of the Alvin replacement vehicle.
Credit: Woods Hole Oceanographic Institution |
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Broadcasters: Animation/B-roll available on Betacam SP. Contact
Dena Headlee, dheadlee@nsf.gov, (703) 292-7739
ARLINGTON, Va.—After 40 years of scientific research that led to
the discovery of new life forms, helped confirm the theory of
plate tectonics, and enthralled schoolchildren around the world
with seafloor images and video, the research submersible Alvin
will be replaced by a new, deeper-diving vehicle.
The National Science Foundation (NSF) will provide funding for
the vehicle through a cooperative agreement with the Woods Hole
Oceanographic Institution (WHOI). A 2004 National Research
Council (NRC) report, Future Needs of Deep Submergence Science,
recommended construction of a new, more capable HOV as part of a
suite of tools for ocean research, which includes remotely
operated vehicles (ROVs) and autonomous underwater vehicles
(AUVs). The preliminary report of the U.S. Commission on Ocean
Policy also points to the importance of research and exploration
of the deep seafloor, and to the excitement emanating from such
missions to the depths of the ocean.
A merit-based review of an unsolicited proposal led to a
cooperative agreement with WHOI for the first phase of
construction.
"Most of the seafloor is unexplored, yet it is one of the most
exciting environments on our planet," said Arden Bement, acting
director of NSF. "This new submersible will be the flagship for
the next phase of deep-sea exploration, and the many exciting
discoveries that are anticipated in coming decades. New
developments in communication technology also will link deep
submergence scientists in real time with shore-side observers to
encourage the next generation of ocean explorers."
The replacement vehicle will be capable of reaching more than 99
percent of the seafloor to depths of 6,500 meters (21,320 feet)
and conducting a broader range of research projects around the
world.
When completed in 2008, it will be the most capable deep-sea
research vehicle in the world. Alvin, which has undergone nearly
continuous upgrades since its launch in 1964, dives to 4,500
meters (14,764 feet).
The four-year design and construction project is expected to cost
$21.6 million and will be funded largely by NSF. WHOI will
operate the new sub as part of the National Deep Submergence
Facility and will provide $2 million of its own funds for the
project: $1 million for enhancements to the submersible's imaging
and lighting systems and other sensors, and $1 million toward
operating costs for the first four years.
The design of the replacement human-occupied vehicle (HOV) for
Alvin is the result of more than 10 years of discussions and
input from the scientific community.
Although Alvin was the first human-occupied vehicle in routine
use in the deep sea and remains the most scientifically
productive vehicle, HOVs operated by Japan, Russia and France now
have some capabilities that surpass those of Alvin, and China is
building its first deepdiving HOV.
"The contribution Alvin has made to science is unquestioned,"
said Robert Gagosian, president and director of WHOI. "Alvin
enabled whole generations of scientists to gain access to a
previously unseen world, and for engineers to push the limits of
their creativity. The replacement vehicle is designed to
continue and extend this legacy."
In addition to diving 40 percent deeper than Alvin can, major
upgrades in the new vehicle include:
- A faster descent speed, and faster submerged forward speed
- Better visibility and lighting for the pilot and two
observers, with five windows-called view ports-instead of the
three on the current submersible
- A variable ballast system that will enable the vehicle to
hover to conduct mid-water research at multiple depths anywhere
in the water column on a single dive
- Improved ergonomics and more space in the 2.1-meter (7-foot)
diameter personnel sphere for the pilot and two scientists
- The ability to carry heavier science payloads, and more
storage space for samples
- Improved sensors, tools and data collection systems
- Improved maneuverability and manipulation, and upgraded
navigation systems
- Higher speed data communication with the surface ship, and
via satellite to shore
The replacement for Alvin will require no major modifications to
the 274-foot Research Vessel Atlantis, its support ship, and its
operating costs will be similar to those of the current Alvin.
The replacement HOV will provide expanded access for scientific
research in areas of the ocean that are virtually unexplored.
Midocean ridge research and the study of hydrothermal and fluid
flow processes on the ridge flanks near oceanic trenches and
along the deeper portion of the continental margins will rely
heavily on the HOV for its unsurpassed observation and sampling
capabilities.
The project leader will be project director Barrie Walden. The
project manager is Robert Brown. Both are long-time members of
the WHOI submersible engineering and operations group, which
operates the current Alvin. In addition, an HOV Replacement
Oversight Committee will include scientists, engineers and other
research vehicle operators from around the country to advise the
project.
Walden noted that the replacement HOV will present a number of
technical challenges. New types of flotation material, capable
of withstanding pressures of nearly 10,000 pounds per square inch
at 6,500 meters depth, must be fabricated and certified for use.
Forging and welding the three-inch thick titanium personnel
sphere is complex. New types of batteries to power the vehicle
will be required, and a variable ballast system must be designed
to adjust for changes in payload, and to enable the sub to
descend and ascend, and hover to conduct research in the mid-
water zone.
Alvin is one of only five deep-diving human occupied vehicles in
the world and the only such HOV in the United States. Alvin
revolutionized deep-sea exploration by providing U.S. scientists
with an unprecedented ability to routinely conduct research on
the deep-sea floor, at mid-ocean ridges and hydrothermal vents
with exotic marine life now believed to hold clues to the origin
of life on Earth.
More than 4,000 dives have transported 12,000 people to the
seafloor to spend 16,000 hours on the bottom to observe and
sample the deep. With a current average of 175 dives per year,
Alvin has a reliability record greater than 95 percent over the
past 20 years, with the remaining percentage lost mainly to bad
weather.
Alvin has been a major participant in historic expeditions, from
Project FAMOUS and the confirmation of the theory of plate
tectonics and continental drift in 1974, to the discovery of
hydrothermal vents in 1977 and black smokers two years later, to
exploring the wreck of RMS Titanic in1986. More than 1,800
refereed science publications include results of Alvin-based
research.
"The replacement HOV will significantly expand our access to the
deep sea allowing researchers to explore the frontiers of ocean
science in areas previously beyond their grasp," said Maurice
Tivey, WHOI's acting chief scientist of deep submergence. "It is
a major step forward in ocean exploration and brings a new level
of versatility and capability to scientists wishing to pursue
research projects on a routine basis in areas they have long
wanted to study but have been unable to reach. HOVs provide
unprecedented 3-D visibility and ease of sampling, put
observations in context, and are an essential tool for educating
students and the public about the meaning and value of deep-ocean
research."
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