Built in 1971, by Halter Marine Services Incorporated of New Orleans, Louisiana (hull #253) as the Esteff S. Defelice for the Defelice Marine Towing Company of Lake Charles, Louisiana.
In 1980, the Defelice Marine Towing Company was acquired by Gulf Fleet Marine Incorporated of Houston, Texas. Where the tug retained her name.
In 1985, Zapata Marine Service, Gulf Fleet Marine Incorporated, and Jackson Marine Services merged to form Zapata Gulf Marine Service Incorporated of Houston, Texas. Where the tug retained her name.
In 1988, the tug was acquired by the Dahl Tug and Barge Company Incorporated of Seattle, Washington. Where she was renamed as the Hunter D.
In 1990, she was acquired by the Sause Brothers Ocean Towing Company of Portland, Oregon. Where she was renamed as the Chinook.
Powered by two, EMD 16-645-E2 diesel engines. With Falk MR 1635 reduction gears, at a ratio of 3.57:1. Turning two, four bladed, skewed, stainless steel, 96(in) by 96(in), right and left, outboard turning, propellers. Mounted in Nautican kort nozzles, for a rated 3,900 horsepower.
Her electrical service is provided by two, 99kW, 75 W Marathon generators. Driven by two John Deere 6068 diesel engines. The tug's capacities are 146,000 gallons of fuel, 7,000 gallons of lube oil,and 8,000 gallons of water.
The towing equipment consists of a Markey TDSD 36, double drum, towing winch. Outfitted with 2,600(ft) of 2.25(in) towing wire on each drum. Driven by a single, GM 671 diesel engine. With three speed, Twin Disc, torque converter. And a, 20 horsepower, horizontal drum windlass capstan on her bow.
(Captain Eric Takakjian, Captain Dave Miner, Jason Purkey, Kyle Stubbs)