Seaspan International is having a very attractive pair of new tugs finished up at their Vancouver Shipyardd ivision. The hulls were fabricated in China and shipped across the Pacific by barge. When the two 64 by 23-ft. tugs are completed with the addition of machinery and deckhouses, they will be the result of several years design and planning that included significant input from the operations end of the towing company. Over the past 20 years, Canadian tonnage regulations have created a generation of beamy 50-footers in British Columbia.
These new boats have gone beyond this limit to define a new generation of tug with a fine longer double-chined hull. The hull has a molded depth held to 10.4-ft. to facilitate working some of the shallower areas of the lower Fraser River while providing good water flow to the propellers. This fine hull form, combined with a smooth "slipper" stern will reduce wake wash and lesson the need for the tug to make a "slow-bell" past riverside moorings.
Since the boats will be towing the big boxy wood chip scows, they have been designed so that the aft bulwarks are the same height as the deck of a loaded chip barge while the bow matches the height of an empty barge. Bulwarks are set two feet back from the hull side so that crew can move safely between barge and boat. A total of 17 tons of rubber in soft loop, laminated and D-form will protect the already heavily built hulls from the wear and tear of barge work.
Main engines will be a pair of Cummins KTA38 M0. The engines will be operated at reduced rpm to deliver 600 hp each rather than their full continuous rating of 800 hp or a total of 1600 hp, although in times of high river this can be adjusted upward. The mains will turn into TwinDisc 540 marine gears with 5.19:1 rations.
The 72x62-in. propellers will turn in Harrington Kort19 A nozzles. The TwinDisc gears will provide for counter rotating propellers to give maximum efficiency in handling and in drawing water flow.
The four Cummins main engines were installed in the boats in late March with plans for the new tugs to be in operation by summer.