Ice class Seaway tug now at production design stage

Tug will have ice-breaking bow form

FEBRUARY 22, 2018 — Robert Allan Ltd. has released more details of the ice class TundRA 3600 tug that Gulf Island Shipyards is to build under an $18.4 million contract awarded by the Saint Lawrence Seaway Development Corporation (SLSDC) last October (see earlier story).

The tug, which will be based in Massena, NY, will primarily operate between the Snell and Eisenhower locks on the Seaway, with typical duties including icebreaking/ice-management services, handling navigation aid buoys, and pushing the SLSDC’s buoy and gate lifter barges. The tug is also capable of secondary roles in fire-fighting and pollution response.

The tug design is of relatively shallow draft, to be classified by ABS as an Ice Class 1A tug, and incorporates an ice-breaking bow form. It is powered by a pair of EPA Tier 4 compliant engines with SCR after-treatment, to deliver a bollard pull of approximately 65 long tons via controllable pitch Z-drive propulsion units.

The vessel is equipped with a heavy duty deck crane, a stern roller, shark jaws, and a tugger winch for ease of handling aids to navigation on the aft working deck. All equipment is rated for operating in the notoriously cold local winter conditions, and the decks feature a heat tracing system to reduce the accumulation of ice and improve the safety of crew operations on deck.

Barge winches and push knees on the forward deck, along with a towing winch within an enclosed house aft allow the tug to handle barges off the bow or the stern, and the elevated wheelhouse provides a commanding view while pushing a barge ahead.

Typical complement will be 4-6 crew, however comfortable accommodations are provided for up to 14 persons for extended buoy run missions.

Principal characteristics of the tug are as follows:

• Length, overall: 118′-0″ (36.0 m)
• Beam molded: 45′-0″ (13.7 m)
• Depth, least molded: 19′-7″ (6.0 m)
• Design draft (navigational): 16′-0″ (4.9 m)
• Fuel: 35,000 gal (135 m3)
• Fresh water: 7,500 gal (28 cu.m)

The tug’s full classification notation is as follows:

ABS ✠ A1 Towing Vessel (FF Capable, BP), Domestic Service, Ice Class 1A, ✠ AMS, ✠ ABCU, IHM

The inventory of hazardous materials (IHM) class notation, along with the emissions-friendly propulsion package, noise reducing features, and light pollution response gear aboard will make this tug an especially strong performer from an environmental standpoint.

Production design of the tug is currently well underway, with delivery of the vessel from Gulf Island’s Jennings, LA, shipyard expected in the summer of 2019.