Built in 2009, by Diversified Marine Incorporated of Portland, Oregon (hull #21) as the Sesok for Crowley Marine Services Incorporated of San Francisco, California.
She was the third Avik class tug built for Crowley Marine Services Incorporated. She was the second Avik class vessel to by constructed by Diversified Marine Incorporated.
The Avik class tugs were designed for utilization with oil barges in the coastwise, and river trades of Western Alaska. Their stern configuration shrouds the triple screw propellers in tunnels. Enabling these tugs to work at very shallow drafts.
She also features propulsion and auxiliary engines that meet all IMO emissions requirements. Forward fuel tanks surrounded by void spaces on the sides to minimize the change of fuel spills in the event of collision. And, holding tanks to retain all treated sewage on board and electric deck machinery to prevent hydraulic oil spills.
The bow hull form provides seakeeping qualities that allow these tugs to engage in ocean towing as well. A tow winch allows the boat to engage in coastal towing while fendered knees on the bow allow for operation in the push mode during river operations.
Powered by three, Tier II compliant, Caterpillar C-18 diesel engines. With Reintjes WAF 244 MKK reduction gears, at a ratio of 2.957:1. Turning three, stainless steel, fixed pitch propellers. She is a square bow, triple screw, push boat. Rated at 1,000 horsepower.
Her electrical service is provided by two, Caterpillar 3304 DITA, auxiliary engines. The tug's capacities are 23,900 gallons of fuel, 900 gallons of lube oil, and 3,900 gallons of water, with a water maker.
The design also features forward fuel tanks surrounded by void spaces on their sides to minimize the chance of fuel spills in the event of collision. Holding tanks to retain all treated sewage on board and electric deck machinery to prevent hydraulic oil spills.
The towing equipment consists of a Markey TES-22, single drum, towing winch. Outfitted with 1,250(ft) of 1.25(in) towing wire, mounted on her stern. And two, Patterson, 60 ton winches, outfitted with 1.8(in) wire, mounted on her bow.