Alaska Marine Highway System
EBDG has supported AMHS under an on-call term agreement for naval architecture and marine engineering services for over 25 years. During this time, our scope of work has included projects ranging from complex refurbishments to stability support and hull repair plans.
Most notably, EBDG developed the contract and detail design for the two newest vessels in their fleet, the TAZLINA and HUBBARD. The vessels were constructed a Vigor Alaska in Ketchikan.
EBDG’s Scope
EBDG developed the contract and detail design of the Alaska Class Ferries as well as provided construction support at Vigor Alaska. The versatile Alaska Class Ferry is intended to be a prototype for the next generation of ferries for AMHS to begin the replacement of their aging fleet.
The design is in compliance with US Coast Guard requirements for large passenger vessels (46 CFR Subchapter H) and American Bureau of Shipping requirements for steel vessels of less than 90m in length. The ferry has an overall length of 280', has a beam of 67' and a draft of 12.5' and carries 53 vehicles and 300 passengers.
During the design phase, our scope of work included managing the public process effort. This involved public meetings with 12 different communities, a project website, meetings with three trade unions, and answering over 150 written comments. Our team applied the Informed Consent approach, also known as the Bleiker Method, to build a consensus around the design.
Vessel Particulars
Owner:
Length:
Beam:
Regulatory:
Capacity:
Alaska Marine Highway System
280’
67’
USCG Subchapter H and American Bureau of Shipping
300 passengers and 53 vehicles
Design Features
The vessels are designed with twin side casings with walk-on passenger access and drive-through vehicle loading and unloading. Vessel propulsion is a twin-screw arrangement powered by two EMD 12-710, 3000 BHP engines, enabling the vessels to have a service speed of 16 knots at 85% of maximum continuous rating. The vessels are equipped with controllable pitch propellers and bow thrusters for enhanced maneuverability through the pristine Southeast Alaska waterways.
Since fuel efficiency was a critical design goal, the hull form was model tested in Europe with an innovative shafting/rudder system. Winter service in Lynn Canal was also evaluated through seakeeping tests to minimize added resistance in waves.