Friday, August 9, 2013

M/V Hawaii: Teaching Old Tugs a New Trick

In late June, a new 120-foot by 35-foot ocean-going tugboat was christened by June Nakachi, the new vessel’s sponsor, at the JT Marine Shipyard in Vancouver, Washington. The M/V Hawaii was built as the first of two vessels in a venture by newly-formed Hyak Maritime LLC. Hyak co-owners Gordon Smith and Robert Dorn hope to build a series of these vessels to replace an aged fleet of US line-haul coastal and ocean tugs, most of which are nearly 40 years old. Hyak’s second tug, the M/V Washington, will be delivered by the end of the year.

“We expect to build several more of these boats to lease to operating tug and barge companies,” Dorn says. He notes that while the US ship-assist and ship escort tug fleet is fairly modern, there has been little innovation in the US ocean-going line-haul fleet for decades. “In 2011, we did an in-depth study of the US coastal towing industry,” he says. “It became clear that the boats that made up the largest working segment – 335 boats with 4,000 to 6,000 horsepower – were some of the oldest tugboats in the country.” Dorn notes that these are the most properly sized tugs in most of the large US company fleets and are indispensable to move our most common sizes of ocean-going fuel and freight barges on the coasts and across the oceans. Most of these boats now cannot work in California without paying heavy state fines, are in violation of evolved MARPOL rules and cannot sail to foreign countries.

Dorn predicts that the 4,000 to 6,000-HP tugboat will continue to make up the largest component of the US coastal market, based on the sizes of the ocean-going freight and fuel barges that continue to be regularly built in US shipyards.

“The tug requirements for the US coastal barge fleet will remain the same as they have been for decades; but operators and their customers could enjoy much lower fuel, operating, and maintenance/repair costs with safer, more modern boats that are allowed to go anywhere in the world, ” Dorn states.

Most US transportation industries rely on standardized equipment, whether it be a rail car, a truck/truck trailer, or a 737. In considering how a standard ocean-going tugboat should be, Hyak consulted Bob and Ric Shrewsbury of Seattle-based Western Towboat. Their company builds its own tugboats, and is currently working on the seventh Titan-class ocean tugboat utilizing azimuthing stern drives. “The Shrewsburys and their Port Engineer, Ed McEvoy, have developed the perfect tugboat to perform the most difficult weekly scheduled towing job on the planet,” Dorn says. The vessels move 420-foot by 105-foot loaded rail/freight barges from Seattle to Whittier, Alaska across the notorious Gulf of Alaska at 10 knots, and then moor the barges in a remote difficult port without needing assist tugs. “The Western Titan boats hit the power, the speed and the maneuverability ‘sweet spots’,” Dorn says. “Gordon and I are very grateful that Western Towboat and their naval architect, Jensen Maritime, licensed us the use of their design.”

Hyak is powering the Hawaii with a pair of medium-speed 900-RPM General Electric 8L250 EPA Tier II engines coupled by Centa connectors and carbon-fiber shafting to Schottel FP1515 azimuthing stern drives. Dorn expects that virtually no maintenance will be required on the power train for 40,000 hours. “I budgeted an average of $350,000 in annual maintenance and repair costs to a machinery-class 5,000 HP tug during my days towing ocean tank barges at Sea Coast and Sirius,” he says. “Getting to 40,000 hours without overhauls is about 7 years without that annual number pinned to the tug.”

The projected fuel and lubricating oils savings for the Hyak boats are also remarkable. The GE four-stroke medium speed engine uses 18 percent less fuel than a high-speed four-stroke engine of similar horsepower, and unlike the industry standard two-stroke medium speed engine boats, consumes no lubricating oil. “I kept comparing the fuel power curves of the GE engines to similar horsepower engines and realized that I could expect to save more than 800 gallons of fuel and 30 gallons of lube oil daily over my normal Sea Coast or Sirius tug.” At $3.00/gallon for diesel and $8.00/gallon for lube oil, the numbers showed that using the Hawaii would have saved him more than $700,000 in fuel costs annually over one of his older boats. “Gordon and I were trying to find instances in our histories of towing barges around the Pacific where we would have preferred the tug we actually used over the Hawaii , he says. “We couldn’t think of a single instance where the Hawaii would not have made one of our tows cheaper, faster, and safer.”

The Hyak vessels are being offered out on long-term bareboat charter. The Hyak goal is to have the Titan class boats become the industry preference. “Tugboatmen typically have very specific ideas about what they want in a boat and what will work for their particular companies. It’s been very gratifying to have many tug industry leaders visit us during construction and tell us that they love the boat and it could easily tow their barges. Trust me, tugboat guys would tell us if they didn’t like it,” Dorn says.

During sea trials, the Hawaii measured 82.5 tons of bollard pull, and 14.5 knots free running speed. “This was even better than we expected, and means that our performance standard –pulling a loaded 420-foot barge at 10 knots – has been met. It has the fuel efficiency of a 4,000-horsepower boat but pulls like a 6,000-horsepower boat.”

The tug is set up for both barge towing and barge pushing modes, and the hydraulic deck machinery, provided by JonRie, is all fully visible and controlled from the pilothouse. The double-drum tow winch has 2,600 feet of 2 ¼-inch wire on one drum and 1,800 feet of 2-inch wire on the second drum. The headline winch has 450 feet of 7-inch plasma line. Two John Deere 6081 Kohler gensets each provide 195 kW of electrical service and each genset is also plumbed to provide full hydraulic power to the winches.

The Hawaii and Washington each measure 91 US regulatory tons and 497 international tons, allowing the vessels to operate with the smallest crew complement possible in US and international waters. The ABS A1 Maltese Cross Towing certification with Marpol annexes compliance allows each vessel to sail to all international ports. The living quarters are acoustically dampened and fireproofed to the highest international crew comfort and safety standards, and a Daikin HVAC system conditions each cabin or crew space individually.

While admitting that a tugboat is already a complex machine, Dorn says in the case of the new Hyak boats, simplicity is the name of the game. “We’re building a very straightforward tug that will be pretty simple to operate and maintain, and will provide tug companies and their customers substantial cost savings while meeting the new regulatory requirements. We think we met our goal of taking Western Towboat’s great Titan-class boat and modifying it to suit a broad range of operating companies’ requirements,” he says.