The fishing vessel Birgit-N, first crabber/trawler built by Tacoma Boatbuilding for Bering Sea service, was delivered to Peter Njardvik and A.O. Nordheim to join their other vessels in the rigorous and highly competitive Bering Sea crab fishing. The vessel's design, by B.F. Jensen and Associates, incorporates several features that improve the efficiency of the trawler.
The new boat has an overall length of 123 feet, beam of 32 feet, and depth to main deck of 16 feet. Propulsion is by a Caterpillar D399 diesel with an output of 1,125 bhp at 1,225 rpm, providing a speed of 12 knots through 4.5:1 reduction gearing. The engine is controlled by Mathers Controls equipment. Electric power is provided by three Caterpillar generators—two model 3406 each of 210 kw and one model 3304 of 90 kw. The hydraulic system is by Vickers.
The Birgit-N has four crab tanks with a total capacity of 8,800 cubic feet, each tank being insulated with 6 inches of closed-cell urethane foam. This four-tank arrangement allows for ease of loading crab, and also facilitates handling of salmon when the vessel operates as a tender during the Alaskan salmon season.
A 60-ton York refrigeration plant is installed to maintain fish in the tanks at a temperature of 30 F in chilled seawater. Sumps located in the forward tanks and a sliding watertight door between tanks will allow rapid discharge of the frozen salmon via a fish elevator through the forward tank hatches.
A major benefit of the four-tank arrangement is a shaft alley allowing access from the engine room to the steering compartment and lazarette below decks. The circulation pumps are located in the shaft alley, thus leaving more usable space in the engine room. All compartments below the deck are protected by watertight doors.
The efficiency of Birgit-N's design is enhanced by the use of two 10-ton cranes both supplied by Northern Line Machine, a division of Tacoma Boat. The forward crane has a reach of 36 feet, and will serve as the picking boom. The aft crane is a unique level-luffing design with a reach of 48 feet. The level-luffing feature of this crane allows the operator to raise and extend the boom without the need to constantly pay out or haul in line. No matter how the boom is manipulated, the line length remains fixed. This arrangement is said to be safer, faster, and more precise than existing installations. Both cranes are controlled by hydraulic servos on the main control valves that are located in the engine room.
The boat is also equipped with a pair of trawl winches, a stern ramp, and a Northern Line net reel to allow the Birgit-N to trawl for bait fish.