Salute to the F-117 with a faceted design

Dc1

It’s been six years since Reinauer Transportation Co. took delivery of its first “facet tug” built with a hard-edged steel hull instead of the standard faired shape.

The company, based in Staten Island, N.Y., has taken delivery of four Ruth-class tugboats since then, all built at Senesco Marine in North Kingston, R.I. The fifth such vessel, Dylan Cooper, is nearly finished and a sixth is in the early construction stage. 

Chris Reinauer, manager of construction, said the vessels are proven workhorses despite the unusual design. 

"As unconventional as this is, it’s not as bad a sea boat as it looks,” Reinauer said during an early April tour of Dylan Cooper, which is slated to begin sea trials in June. “It’s really performing every bit as good as a conventionally designed hull. We really have no complaints, otherwise we wouldn’t be building a fifth one.”

From left, Senesco Marine’s Michael Moore, George Wu and Billy McClinton inside Dylan Cooper during construction.

The 126-foot Dylan Cooper will be paired with RTC-108, a 413-foot 100,000-bbl fuel barge, and linked with 34-inch Intercontinental C-series coupler system. The vessel was built on spec, but Reinauer expects steady work starting this summer. Other Ruth-class tugs are operating on charter in the Gulf of Mexico, Canada and along the Eastern Seaboard. 

The latest facet tug has much in common with its sister vessels. These include Lufkin 7.5:1 marine gears and three-bladed Nautican 104-inch propellers with Nautican nozzles and triple-shutter rudders. The company purposely uses the same components to share parts across the class, Reinauer said.
 
That’s not to say Dylan Cooper is identical to previous models. Perhaps the biggest change is the Nautican independently controlled rudder system that can be activated with the push of a button. The company added the capability after crew requested more power astern during twin-screw operations. 

“We decided we would experiment and see if it works out,” Reinauer said. “We’re hoping it makes a difference.”

A cutaway of Dylan Cooper.

Dylan Cooper is designed to cruise at 9.5 knots fully laden and 13 knots light. Power comes from two MTU 16V-4000 M64 diesel engines rated for 2,400 horsepower each at 1,800 rpm. The engines could produce more than 2,600 hp, but they’ve been tuned to match other engines in the fleet, Reinauer said. Backup electric power comes from three John Deere 6068 TFM generators.

The third backup generator is one of many redundancies built into the vessel to maximize work time. Others include two hot water heaters, two wash water pumps, two ballast pumps, two fuel pumps and two air conditioning units. The company learned years ago that spending more during construction can save money in the long run by avoiding repairs and lost time down the road.

“Most of our competitors do not have three generators down below. They run two and a SOLAS, because the requirement is for two generators and a backup SOLAS. We can fail a generator, legally leave port and go to another port. If they fail a generator, they can’t legally move,” he said. 

The vessel also has a John Deere 4045 TFM emergency generator to meet SOLAS standards. Other items that distinguish Cooper from the company’s earlier non-SOLAS tugs include a Furuno RC1815 GMDSS, enhanced fire suppression systems and lifesaving systems, and a rescue craft.

Tom Mobray, an alignment specialist for Senesco Marine, makes sure the bearings are set precisely on one of Dylan Cooper’s Nautican propellers.

Other parts of the vessel were designed to reduce headaches down the road. These include installation of aluminum hatch covers, piping, vent covers and other components that can’t easily be painted. Also unusual for a tug of this size: its double-hulled steel construction with 1-inch-thick steel plating along the flat bottom and double-continuous welding throughout. 

The flat bottom and other unusual hull design characteristics were created out of necessity. When Reinauer Transportation acquired Senesco Marine in 2006, the shipyard mostly built barges. The company turned to Ocean Tug & Barge Engineering of Milford, Mass., to design a “shipyard-friendly” tugboat that could be assembled more easily and at lower cost than a curved hull. 

Naval architect Robert Hill, president of Ocean Tug & Barge Engineering, said the design concept dates to the 1940s, when the U.S. Navy explored easily assembled vessels ahead of a possible invasion of Japan. The tugboat’s final design also was influenced by the U.S. military’s F-117 stealth fighter. 

“All of the angles that are used in the boat are optimized. It’s not just a collection of flat plates approximating a round hull,” Hill said of the facet tugboat. “There is definitely a rhyme and reason to each plate’s angle.”

Nautican propeller in position.

The design met resistance from other naval architects who thought the vessel wouldn’t perform, Hill recalled. Some actually encouraged Reinauer to abandon the plan. These critics were ultimately proven wrong after the first vessel was delivered in 2009, Hill said, as performance has exceeded expectations. 

The facet tugs also help Reinauer Transportation’s bottom line. George Wu, a project manager at Senesco Marine, said the design reduces labor costs. Build time on the vessel can be as short as 16 months, although the average is closer to 20, he said. 

Dylan Cooper has a crew complement of seven, although it will occasionally have trainees, cadets from maritime academies or an assistant engineer. The tug feels spacious for a vessel of this size, thanks to a step deck that houses air conditioners and other components. 

The vessel has seven cabins, five of which are on the main deck while the captain and mate’s quarters are on the second deck. The vessel has wireless Internet hotspots and satellite is available in the cabins. A big-screen TV will be installed in the vessel’s dining area. 

The engine room of Dylan Cooper. The vessel is powered by two MTU 16V 4000 diesel engines.

“Helping crew with their rest time improves their ability to perform their day-to-day tasks and only adds to our company’s performance standards,” Reinauer said. 

Dylan Cooper, which is named for John Reinauer’s two sons, will join a company fleet that currently features 24 tugs and 25 barges. Although the facet tugs are each “married” to a specific barge, the tugs are compatible with most other barges in the fleet. 

While the facet tug was something of a novelty when it was introduced, it has proven durable, reliable and plenty capable at sea. That’s what Reinauer Transportation expected when it took a chance on the unconventional design all those years ago.

By Professional Mariner Staff