Bookmark and Share Email this page Email Print this page Print


Oct 24, 2013 02:30 PM

North through the Arctic ice: Marinette sets new standard

(page 2 of 2)

Sikuliaq will operate worldwide at various times of the year. During non-polar voyages, the research ship will be moved by efficient five-blade propellers, which provide more thrust than the Wärtsilä ice-class props, which Hoshlyk said have only four stubbier blades.

From left, J. Marc Willis, marine science technical director; Gary Smith, University of Alaska-Fairbanks; Dale Jalkanen, Marinette Marine.

“It’s definitely a beefier propeller, where the edge of the blade is not as sharp as you would have on an ocean cargo vessel,” the captain said. “We will have replacement ocean blades, which we can switch out in a quick dry-dock.” The projected fuel efficiency increase is 50 percent.

The scientists and designers wanted a vessel that comes as close as possible to meeting international fisheries research standards for underwater radiated noise, known as ICES 209. At this level, an underway research vessel is not loud enough to scare away schools of fish. Sikuliaq does not meet the standard at its maximum cruising speed of 14 knots.

“This was really a big challenge because it’s an ice-going vessel and we wanted to get as close as we could to the underwater radiated noise standard,” Kristensen said. “We’re trying to be a quiet ship at up to 8 knots. Where this really becomes difficult is in the design of the propellers, because the propellers need to be able to break ice and be able to withstand ice impacts.”

Soundproofing is evident throughout the ship, including Soundown noise and vibration controls.

“We put on a lot of sound absorption tiles — on the vessel, on the machinery spaces,” said Smith, the university’s project director. “And just about anything that’s rotating or humming is resilient-mounted. We don’t have any radiated noise from the structure of the hull … into the ocean. Cavitation is a big contributor to underwater noise. We had to cut down on cavitation and still get the thrust we need and the bollard pull we need.”

Aside from the main lab, which is full of work benches and power receptacles, there is a separate analytical lab, science freezer, chill rooms, and computer lab with fiber network. A wet lab is located alongside Sikuliaq’s large Baltic room, which is fitted with an overhead hydraulic load-handling system.

“It’s basically a hands-off handling system for deploying things over the side and it’s motion-compensated,” said Marc Willis, the project’s science technical director.

Rapp Hydema was the systems integrator for the scientific handling equipment and winches, and Kongsberg provided the sonar systems. Siemens was the propulsion systems integrator, while Marine Technologies was the integrator for navigation electronics.

On the working deck are two 30-ton-rated Appleton Marine cranes plus a hydraulic A-frame. All can be manipulated from a single operating station or wireless belly pack.

Russ Patton of the yard’s electrical engineering department.

“The A-frame — the big square rig that sticks off the stern of the vessel — has a 180-degree operating radius to reduce the ice’s impact on towing wires,” Hoshlyk said.

The ship will routinely deploy a conductivity temperature depth profiler, which tests salinity and other conditions in water samples at isolated locations of the water column. The handling equipment is capable of lifting a remotely operated vehicle, putting it in and out of the sea and moving it to storage.

Sikuliaq will carry scientists to zones ranging from the Arctic to the tropics, necessitating greater heating, ventilating and air-conditioning capabilities than the average ship.

“The challenge is the vessel has to be able to operate globally, and that was a bit of a design change from the marching orders we had for several years,” Kristensen said. “It has a pretty hefty HVAC plant on board to accommodate a wide range of weather conditions. The machinery cooling system has to take into account possible blockage from ice, so there is a sizable sea chest.”

In accordance with UNOLS standards, Sikuliaq’s main science deck and public areas comply with the Americans with Disabilities Act. One stateroom is designed to accommodate a person in a wheelchair. And a sauna has been installed near the living quarters.

“That’s a carryover from traditional ice-breaking ships,” Smith said. “It’s pretty nice to have, but it’s also for (treating) hypothermia from working out in the cold. If you go on any Finnish or Russian icebreaker, you’ll see a sauna.”

After sea trials, Sikuliaq is scheduled to begin operations in the Arctic next August. The master, who has six years’ experience in the Bering Sea aboard National Oceanic and Atmospheric Administration research vessels, is ready to take the scientists where they want to go.

“We’ll have a nice, robust vessel,” said Hoshlyk. “The challenge now will be how far you have to go to refuel and reprovision and do crew change-outs. ... We’ll push it to its limits, within reason. As the multi-year ice decreases, our range will increase.”

Add your comment:
Edit Module