Page 45: of Marine News Magazine (October 2015)

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PROPULSION

A Thunderbolt of an Idea for Inland Operators

Eastern’s new inland towboat design personi? es the movement towards purpose-built and designed tonnage that matches all equipment – including propulsion – to the platform itself.

By Joseph Keefe ust a few months ago, Eastern Shipbuilding (ESG) age, instead of being procured in a stovepiped, standalone introduced the Thunderbolt, a new inland towboat basis. On the other hand, ESG’s experience with the proven

Jdesigned to capture better ef? ciencies, performance, Platform Supply Vessel “Tiger Shark” diesel electric and pro- improved maneuverability, and other important metrics. pulsion technology design, leveraged with Eastern’s ongoing

Notably, the 4,200hp Thunderbolt will be out? tted with inland towboat construction program, kicked off the research twin azimuthing Verhaar Omega electric V-Pod propul- and development phase of the program in November 2013.

sion and diesel-electric technology. Gilbert Associates, Inc. (GAI) became an integral part of

The ESG design involved collaboration with naval ar- the Thunderbolt team when ESG approached GAI looking chitects, propulsion OEM’s and also relies on the advice of for a conventional towboat design of about 110 feet LOA. inland operators. The concept incorporates the common GAI President John Gilbert explains, “The design length sense strategy of making sure that azimuth technology, has grown to 120 feet and since has been widened. The when applied to any hull, is also done so in a manner that initial design package consisted of a preliminary lines plans, will maximize its utility. In this case, the inland markets are inboard pro? le, outboard pro? le, and general arrangements

ESG’s focus for the Thunderbolt. Eastern is anything but which was enough for the presentation to Eastern’s Senior a stranger to inland boatbuilding, having has constructed Management for design funding approval. This was fol- and delivered on-time and on-budget as many as 85 inland lowed by the additional engineering required to bring the vessels of all types since 2006. Today, its inland backorder ? nal Thunderbolt concept design as it exists today.” book boasts no less than 18 vessels. Two of the most signi? cant design challenges for GAI

It is (arguably) unusual for a shipyard to come up with its were the development of the hull tunnels to which the own turnkey design, but inland ‘teams’ are now more com- Omega V-Pod’s would reside as well as the V-Pod hull struc- mon, as operators, shipyards and naval architects push the ture and top mount cans, the weight and trim of the vessel. concept that all OEM equipment has to ? t into a bigger pack- Gilbert explains, “The machinery of a diesel electric boat 45 www.marinelink.com MN

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