Rygerkattall — carbon fiber composite passenger ferry
Shipbuilder Brødrene Aa (Hyen, Norway) recently launched the Rygerkatt, an all-carbon fiber composite passenger ferry, built for Norway's largest passenger ferry operator, Rodne & Sønner.
Shipbuilder Brødrene Aa (Hyen, Norway) recently launched the Rygerkatt, an all-carbon fiber composite passenger ferry, built for Norway's largest passenger ferry operator, Rodne & Sønner. The 18.5m/60-ft long catamaran, designed by Hareide Designmill (Fredrikstad, Norway), is a cored sandwich construction, made with vacuum infusion methods in open female molds. Stitched multiaxial carbon fiber reinforcements, supplied by Devold AMT (Langevåg, Norway), form the skins. The layup incorporates unidirectional, biaxial and triaxial carbon fabrics in various locations, depending on design loads. The carbon fiber is a T700 FOE from Toray Industries (Toyko, Japan), sized for compatibility with the vinyl ester infusion resin. Closed-cell Divinycell PVC foam from DIAB Inc. (Laholm, Sweden) comprises the 50-mm/2-inch thick core material. Brødrene elected to paint the vessel rather than use a clear coat or gel coat.
Because of carbon's lower weight and the fact that less material was needed to achieve design specifications, the Rygerkatt weighs 40 percent less than it would if traditional composite materials had been used. The lighter ferry boasts significantly better fuel economy, even with 62 passengers aboard on a harbor route with more than 200 stops per day, which helps to offset the carbon's higher cost. The ferry's top speed is 29 knots/33 mph, fast for a passenger vessel. Natural damping characteristics and cored construction give passengers a quiet ride, with the noise level in the cabin less than 70 db at full speed. The Rygerkatt is the second in a series of commercial carbon fiber vessels — the first was the Ryger Doktoren, a high-performance carbon fiber composite ambulance boat with a top speed of 44 knots/50 mph. More carbon fiber ferries are likely.
Brødrene has produced many large composite vessels, including the Moonraker, the world's fastest luxury yacht, at a length of 35m/115 ft. It also produces composite parts for rail transport and industrial applications.
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