FEBRUARY 13, 2015 — Eastern Shipbuilding Group, Inc., Panama City, FL, is introducing the Thunderbolt, a 120 ft, 4,200 horsepower inland towboat design that combines diesel-electric technology with twin electric Verhaar Omega V-Pod propulsion.
Thruster propulsion systems are gaining increasing attention from river operators, outperforming conventional nozzle propeller propulsion systems with main/flanking rudder steering and the idea for the Thunderbolt developed from across-the-aisle conversations at a 2013 tradeshow when Eastern Shipbuilding got into discussions with thruster specialist Verhaar Omega, B.V. of the Netherlands.
Eastern and Verhaar Omega, which has been represented in the U.S. by Sewart Supply, Inc., Morgan City, LA, for more than ten years, realized they were driving towards a more refined towboat thruster propulsion system design and, as a result, the Thunderbolt is equipped with twin Verhaar Omega 690 V AC electric V-Pod units and twin Omega Propulsion AFE/VFD Drives.
The twin independent V-Pods have 360 degree rotation and can rotate 180 degrees in approximately 14 seconds. For superior maneuverability and precision, the twin V-Pods each have 1,320 kW (1,770 HP)VFD-reversing induction motors.
The V-Pods are installed from the top, avoiding emergency dry-docking if a unit is damaged.
Eastern has delivered 19 diesel-electric offshore supply vessels since 2010 and 74 inland towing vessels since 2007 and the Thunderbolt integrates Eastern's offshore-proven Tiger Shark Class diesel-electric technology into a refined, environmentally friendly, highly maneuverable inland towboat design.
Cummins Mid-South, LLC is providing the Thunderbolt generator package, which consists of three identical Cummins QSK38-DM diesel-electric power plants. Each EPA Tier 3 rated, V-12, 38 liter marine diesel engine develops 1,400 hp at 1,800 rpm, giving the vessel 4,200 total installed horsepower. Each engine powers a Cummins AVK DSG-74 water-cooled generator, delivering 990 kW, 690 V AC at 1,800 rpm.
This system performs seamlessly with the Power Management System (PMS), provided by Beier Radio, LLC to optimize fuel consumption without sacrificing power and performance. An IEM Marine, Inc. switchboard automatically starts and closes the appropriate main bus generator breakers with load-sharing controllers. The pilot is free to utilize the automated power management systems as much or as little as required, keeping full control of the entire power management system at all times.
Putting together the V-Pod propulsion and diesel-electric with constant speed generator engines along with power management and automation adds up to less vibration and noise and results in lower operating costs, system redundancy, increased safety, increased crew comfort and less crew fatigue.
Eastern says the fuel savings of the Thunderbolt versus traditional inland towboats is dramatic. Twin V-Pod thrust and fuel consumption calculations, which include ship's services, are:
40% V-Pod Thrust: 37,740# @ 92 USG/hr. (2,208 USG/day)
78% V-Pod Thrust: 73,593# @ 164 USG/hr. (3,936 USG/day)
100% V-Pod Thrust: 94,350# @ 194 USG/hr. (4,656 USG/day)
Eastern Shipbuilding has worked with naval architect Gilbert Associates, Inc. for more than a year on the design, which meets ABS Class Rules for Building and Classing Steel Vessels for Service on Rivers and Intracoastal Waterways-2014 and is also designed to the proposed U.S. Coast Guard 46CFR (Sub-Chapter M) Towing Vessel Rules and IEEE 45 2002 Standards.
Vessel dimensions are:
- Length (Molded): 120'-0" (36.57 m)
- Beam (Molded) : 36'-0" (10.97 m)
- Hull Depth Amidships (Molded): 11'-3" (3.42 m)
- Hull Depth Head Log (Molded): 13'-3" (4.03 m)
- Hull Depth Stern Log (Molded): 12'-9" (3.88 m)
- Design Waterline (DWL) : 9'-6" (2.98 m)
- Pilothouse Eye Level above (DWL): 34'-3" (10.43 m)