HR: 0800h
AN: V51C-1489    [Abstracts]
TI: Mission Accomplished: Deep Submergence Science Routinely Supported Using Multiple Vehicles Throughout the Hawaii Undersea Research Laboratory's 2005 South Pacific Expedition
AU: Kerby, T
EM: tkerby@hawaii.edu
AF: Hawaii Undersea Research Laboratory, University of Hawaii, 1000 Pope Road, MSB 303, Honolulu, HI 96822-2336 United States
AU: * Smith, J R
EM: jrsmith@hawaii.edu
AF: Hawaii Undersea Research Laboratory, University of Hawaii, 1000 Pope Road, MSB 303, Honolulu, HI 96822-2336 United States
AU: Shackelford, R
EM: shackelf@hawaii.edu
AF: Hawaii Undersea Research Laboratory, University of Hawaii, 1000 Pope Road, MSB 303, Honolulu, HI 96822-2336 United States
AU: Wiltshire, J C
EM: johnw@soest.hawaii.edu
AF: Hawaii Undersea Research Laboratory, University of Hawaii, 1000 Pope Road, MSB 303, Honolulu, HI 96822-2336 United States
AU: Malahoff, A
EM: malahoff@hawaii.edu
AF: Hawaii Undersea Research Laboratory, University of Hawaii, 1000 Pope Road, MSB 303, Honolulu, HI 96822-2336 United States
AU: Malahoff, A
EM: malahoff@hawaii.edu
AF: Institute of Geological and Nuclear Sciences, PO Box 30-368, 69 Gracefield Road, Lower Hutt, 6009 New Zealand
AB: The Hawaii Undersea Research Laboratory (HURL) recently completed an internationally partnered 5-month, 14,500 nautical mile multiple leg expedition to the South Pacific that included 21 study sites in the waters of American Samoa, New Zealand, Tonga, and the U.S. Line Islands to commemorate its 25th anniversary of supporting deep submergence science in the Pacific Ocean. During this voyage, HURL successfully operated its two human occupied vehicles ( Pisces IV and Pisces V) each capable of diving to 2000 m from their support ship, the R/V Ka'imikai-o-Kanaloa ( KoK). In addition, a remotely operated vehicle ( RCV-150) with a nearly 1000-m depth limit was utilized alternately with the Pisces HOV's. The size and organized placement of these vehicles on the compact but efficiently run KoK (70-m length, 2000-tons displacement, 14 crew) allowed for deployment of a CTD rosette system and recovery of instrument package moorings during the same cruise leg. The Pisces submersibles are 20-ft long, 13-ton, 3-person vehicles with 7-10 hours duration, up to 350-lb payload capacities, and three forward looking viewports. The small size of the Pisces' relative to much larger deeper diving HOV's increases their agility, thus allowing maneuvering into more difficult sampling site terrain. The smaller package also facilitates rapid launch (8 min avg, stdev=1) and recovery (12 min avg, stdev=2) in heavier seas (up to sea state 5), as routinely experienced in the South Pacific during the austral winter. In addition to the enhanced safety aspect of having two compatible submersibles aboard, scientific efficiency has benefited by allowing the rotation of vehicles on extended deployments prior to battery servicing, thus maintaining an overall dive time average of 7.1 hr (stdev=1.52) for an average dive depth of 891 m (stdev=431) in 2005. Having the two fully operational submersibles also provides a contingency for equipment malfunction while on site that saved 7 dive days in 2005 alone. The final dive count resulted in 61 out of 56 scheduled Pisces science dives completed; made possible by careful planning and on-site cruise management and aided by our can-do crew. The RCV-150 was also used on 17 dives when depth and sea conditions allowed, typically in a scouting mode for potential HOV dives to increase the efficiency of the entire operation. The total package described here was made available for less than $30K per dive day in 2005. Standard equipment on the Pisces pair and the RCV-150 are listed at the URL below. In addition, science team equipment was interfaced including the NOAA VENTS fluid sampler and gas tight bottles, Imagenex pencil beam bathymetric sonar system, and the WHOI TowCam external digital still camera. Tracking and navigation accuracy to within 20 m at 1500-1800 m depth was provided by a TrackLink 5000HA ultra-short baseline system interfaced with a MAHRS motion sensor to provide pitch and roll correction. Additional vehicle details, operational results, and statistics for the 2005 South Pacific expedition will be presented.
UR: http://www.soest.hawaii.edu/HURL/
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 3017 Hydrothermal systems (0450, 1034, 3616, 4832, 8135, 8424)
DE: 3075 Submarine tectonics and volcanism
DE: 3080 Submergence instruments: ROV, AUV, submersibles
DE: 9355 Pacific Ocean
SC: Volcanology, Geochemistry, Petrology [V]
MN: Fall Meeting 2005