The double-ended ferry Croatoan, the third sistership delivered by Steiner Shipyard to the North Carolina Department of Transportation, saw immediate action when she arrived in the Outer Banks in August.
Hurricane Isabel destroyed the ferry landing for Hatteras Village as it cut a 2,000-foot swath through the center of the island, and NCDOT’s other cycloidal-propulsion ferry was committed to its daily high-season route. A conventionally powered ferry couldn’t maneuver up to the improvised landing that NCDOT had been able to construct.
“Amazingly,” said Jerry Gaskill, director of NCDOT’s Ferry Division, “Steiner finished the Croatoan seven weeks ahead of schedule. As soon as she arrived in the Outer Banks, we put her into service carrying hurricane relief and rebuilding supplies to the village. Her cycloidal propulsion and sturdy ramps let us bring her up to an improvised landing safely and regularly.”
Designed by the ferry division’s engineering department, the 180’x44’x11’ boat’s proven hull has a flat bottom for reduced draft—the channel is just deep enough to accommodate her 5’6″ draft—and molded ends for seakindliness.
“Hatteras Inlet is notoriously rough,” Gaskill explained, “and the boat has to keep to a demanding, year-round schedule. We have a lot of experience with this hull, the Croatoan being the third boat we’ve had built, and it’s proven itself in these waters.”
Voith Schneider cycloidal propulsion units, one mounted at each end, propel the Croatoan and also provide an added measure of safety.
Powered by two Caterpillar 3412 diesel engines producing 475 hp each at 1,200 rpm, the independently controlled Voith units offer 360° thrust angles and total control from the wheelhouse’s joysticks. The units’ effectiveness is increased by their placement at the vessel’s ends, since the increased moment, or distance from the boat’s center of rotation, results in greater thrust effect.
“We were primarily interested in saving time,” said Gaskill. “The cycloidal units shave valuable minutes off the normal turn-around time for a three-mile run, but there’s no question that they also provide a safety factor in heavy weather.”
The first of the three 180′ ferries built by Steiner had conventional propulsion. A Voith Schneider unit also powers the second ferry, the Neuse. Built at a cost of $5.38 million, the Neuse was delivered in 1998.
All three sister ferries have room for 300 passengers and 40 vehicles. Steiner has now built six ferries for the NCDOT and converted another.
Gaskill said that NCDOT’s next ferry built to this design— there’s a contract currently pending with Steiner—would also have cycloidal propulsion.
“We’ve been delighted with these boats, and with the service Steiner Shipyard has provided,” Gaskill concluded. “They give the kind of personalized attention and quality of work that really make a difference. We’re considering a fourth boat to this design right now. We’re not sure when we’ll have the money. But one thing is sure, Steiner will be building it.” —M. Hardberger