Leg 6 Underway

By Giora Proskurowski

At exactly 1400 hrs RSN logistics chieftain Larry Nielson slipped the dock lines, and the R/V Thomas G. Thompson got underway for the 6th and final leg of the UW OOI-RSN installation field season. We had timed our port stop to coincide with a large storm that raged offshore– sending an incredible variety of weather ripping past Newport. We were not the only ones to have hunkered down, as three large long-line fishing vessels and the NOAA vessel Bell M. Shimada, made their way out of Yaquina Bay just before us– it was comforting to know that multiple boats had decided the weather had turned. As we exited the channel the swell arriving from the northwest broke with incredible force against the point of the jetty, sending walls of green water and spray at least 30 feet in the air, signaling a lumpy ride ahead.

It is a 24-hour transit from Newport to Axial Seamount, 270 nautical miles away, when the ship is making 12 knots. Currently, we’re riding a bit in the trough (waves are arriving from the west, on our port bow), so the ship can only go 10-11 knots. It doesn’t seem like much, but that one knot speed different accounts for a two hour delay over a 24-hour steam. Our schedule for Leg 6 is incredibly tight, and we need every hour in order to complete the following tasks:
– Dive at International District to deploy high-temperature vent instruments into the 575°F hydrothermal vents “Escargot” and “Diva”
– Dive at ASHES vent field to install a temperature array that failed during deployment, and clean the lens of the HD video camera that has been in place for 13 months
– Dive twice at the 2-leg mooring at Axial Base to install instrumentation and the winched shallow-profiler on the 200 m platform
– Dive twice at the 2-leg mooring at Slope Base to install instrumentation and the winched shallow-profiler on the 200 m platform
We will be back in port on Monday morning, working feverishly around the clock this weekend to tie up all loose ends on this year’s installation of the RSN cabled observatory.