Located in the village of Hyen in Nordfjord, Norway, Brødrene Aa has a long history of innovation and working with Diab. The company is a world leader in manufacturing High-Speed Light Craft from sandwich composites, with tailored designs for a growing range of applications.
Brødrene Aa has been working with sandwich composites and Diab for nearly 40 years. The yard has delivered around 200 vessels with Divinycell FRP sandwich constructions, and for more than a decade it has excelled in working with carbon fiber. The company won the prestigious JEC Composite Awards in 2005 for its vacuum infusion molding process involving skins of carbon/vinylester.
Compared to traditional construction, the use of carbon-fiber sandwich composites reduces structural weight by 40%, giving boats from Brødrene Aa lower fuel consumption and CO2 emissions. At the same time, it makes them both stronger and more rigid, since the composites have 2-3 times the tensile strength and four times the rigidity of fiberglass.
The latest boat to leave the Brødrene Aa yard is the ambulance boat Rygervakt, which is 30th in the line of carbon-fiber vessels produced by the company. While part of a long tradition, the Rygervakt is also a major step forward, since it is the very first ambulance boat constructed with twin hulls.
As a catamaran, the 21 m Rygervakt offers not only greater stability than single-hull ambulance boats, but also a great deal more space. In addition to accommodating up to twelve people, the boat has ample room for sophisticated medical equipment, as well as room for two stretchers and an extra stretcher stowed below deck. Next to the shower there is even a bath for use in treating burn injuries.
Of course, the Rygervakt does share characteristics with its predecessors. From keel to mast if features an optimized combination of several Divinycell H grades delivered by Diab in sheets and blocks that were adapted for core infusion with Toray T700 FOE carbon fiber and Reichold vinylester resin. In addition, it was delivered to the same customer as Brødrene Aa’s very first carbon-fiber vessel, a single-hull ambulance boat for L. Rødne & Sønner.
L. Rødne & Sønner, which provides ferry services along with charter and ambulance contracts, will be operating the Rygervakt as an ambulance in the Norwegian county of Austevoll. Since the boat is equipped with a water cannon that sprays seawater up to 40 meters, it will also be a resource for the local fire department, offering assistance when fires prove inaccessible from land.
For Brødrene Aa as well, the Rygervakt provides a flexible platform that can be adapted to other applications. The basic design, which incorporates a new and highly efficient propulsion system, would require only a two-meter extension to increase passenger capacity by half and enable use as a 50-seat ferry.