Alaska yard launches multi-functional ferry

Alaska Ship & Drydock, Ketchikan, Alaska, has launched what could well be the world's most unusual ferry.

For a start, the Susitna is being funded by the Office of Naval Research'sSea Warfare and Weapons Department.

To be operated on Cook Inlet services by the Matanuska-Susitna Borough, which will own it, Susitna will have three distinct modes of operation: a catamaran mode for high speeds; a small-water-area-twin-hull (SWATH) mode for stability in high sea states; and a shallow-draft landing-craft mode that provides substantial buoyancy for maneuvering in shallow water. In addition, the Susitna will be the world's first ice-breaking twin-hulled vessel.

The ship is designed with a center "barge" that can be hydraulically raised and lowered, while the buoyancy of its catamaran hulls can be adjusted while under way.

ONR also is interested in the vessel's transformational hull form as a technology demonstrator to support Navy sea basing and expeditionary warfare concepts.

Earlier this week the ship was moved from its building pad to its outfitting berth. The Sustina will next go through final outfitting, dock trials, builder's sea trials, and owner's sea trials.

It is expected to enter service this fall.

Vessel Characteristics:

Length 195 ft

Beam 60 ft

Displacement: 940 tons full load

Draft, SWATH mode12 ft

Draft, shallow-draft landing-craft mode 4 ft

Capacity 100 passengers and 20 vehicles.

Speed: 20 knots

Power Plant: 4 x MTU 12V 4000 diesel engines