(This article was originally published on OceanLines on September 3, 2008.)

The 6000m-rated Autosub6000 during seatrials. Photo: NOC Southampton
The Autosub6000, Britain’s new autonomously controlled, robot submarine soon will be diving deep into uncharted waters to search for volcanic vents 6km down in the Caribbean. Once the vents are found the life, sediments, and gasses surrounding the vents will be collected and studied.
The research will be carried out by a British team aboard the James Cook, the UK’s newest research vessel.
“We are heading out on two expeditions, each close to a month long, to map the full length of the Cayman Trough,” said Dr. Jon Copley, team leader, of the National Oceanography Centre in Southampton (NOCS). The Cayman Trough lies between Jamaica and the Cayman Islands and iis a product of the Caribbean tectonic plate pulling away from the American plate.
“It is the world’s deepest volcanic ridge and totally unexplored,” says Copley.
This research is a two-sub mission. Along with the Autosub6000 is Isis, the UK’s deepest diving remotely operated vehicle. Autosub6000 is the latest 6000 m rated version of the Autosub AUV series, which has been used extensively for ocean science during the last 10 years, including work under ice operations in the Arctic and Antarctic. The design of the nose and tail sections including the navigation and control systems, are substantially inherited from the tried and tested Autosub3. The main difference is the depth rating (6000m rather than 1600m), and the energy system (Lithium Polymer rechargeable batteries rather than primary manganese alkaline cells).
First in the water will be Autosub6000, responsible for finding the volcanic vents on the floor as deep as 6km. Second will be Isis, responsible for collecting sample fluids, sediments, and marine life.

Cayman Trough to be Mapped by Autosub6000. Map courtesy of NOC Southampton
“Some of the vents will be very similar in depth to the vents we already know about, and because the conditions will be alike, we might expect very similar animals,” said Copley. “We are hoping to find several different types of vents along the ridge.”
The researchers will look to compare the animals around the Cayman vents to those in the Atlantic and Pacific to better understand how these deep-sea animals get around, if currents play a role or if these deep-sea trences are isolated. If the animals found in the Cayman Trough resemble those from other deep-sea trenches it will suggest that currents play a role in deep-sea life. If the animals are different however, isolation will be considered very important.
“The deep ocean is our planet’s largest ecosystem. If we are going to use its resources responsibly then we need to understand what determines its patterns of life,” Copley said.
Specifications for Autosub6000
Dimensions: 5.5 m long, 0.9 m diameter
Mass: 2000 kg (Dry), 2800 kg (Wet)
Range, endurance: 1000 km at 1 m/s (8.6 days). 400 km at 1.6 m/s. (2.9 days)
Depth capability: 6000 m maximum.
Navigation: 0.1% of distance travelled since last GPS or USBL fix
Telemetry and
Tracking: Linkquest TrackLink 10000 USBL and bidirectional telemetry system
Control Modes: Constant depth, constant altitude (5 to 200m), profiling
Recharge time: 5 hours from fully exhausted lithium polymer battery pack
Standard Sensor
Suite: 300 kHz RDI Workhorse ADCP. Fitting of Seabird 911 CTD be requested from NMFD
There are plans to fit a Mulitbeam system by August 2008.
Payload Capacity: Similar to Autosub3. Large (0.5 m3) volumes free in the nose area for
payloads
Power for sensors: Up to 250 Watts at 48 volts
Data Handling: 100 M bit s-1 TP Ethernet .200 G byte data storage. IEEE 802.11g WiFi for
data download
Shipping: One standard 20 foot shipping containers. Launch and recovery gantry
Source: Underwater Systems Laboratory at the National Oceanography Centre, Southampton
Copyright © 2008 by OceanLines