Diab, a global leader in advanced foam solutions and lightweight composites is celebrating a landmark 50-year collaboration with Brodrene AA, the world leader in the construction of energy-efficient fast ferries.

The partnership has been instrumental in the development of sustainable high-performance foam cored structures with carbon and glass fibre reinforced composites for the maritime, rail, subsea and industrial sectors.

Founded in 1947 by brothers Olav Aa and Bertel Aa, Brodrene AA began as a shipyard crafting leisure boats from mahogany and other timbers. The shift to composite materials began in the mid-1970s inspired by the launch of the glass-fibre composite reinforced Minesweeper HSwMS Viksten by Saab Kockums. Partnering with Diab, Brodrene AA then ventured into foam cored production marking a pivotal moment with the launch of the Haaen, the world's first foam sandwich passenger vessel in 1975. The launch of the 85-foot catamaran Hyen in 1979 marked another significant milestone, combining Norwegian Maritime certification with DNV class approval. The Hyen remains operational in Iceland today.

Throughout the 1980s and 1990s, Brødrene AA continued to push the boundaries of glass-fibre composite construction. The 1992 launch of Moonraker, a 36 metre superyacht with a top speed of 66.7 knots, highlighted the performance capabilities of lightweight Diab-cored structures.

The late 1990s saw Brodrene AA build superyachts and rail components, as well as pioneering infused carbon fibre and foam sandwich structures for ferries, resulting in vessels that are 30-40% lighter than their aluminium counterparts. This significant weight reduction translated into up to 40% fuel savings, further enhancing the efficiency and sustainability of its ferries. The shipyard has since launched approximately eighty carbon fibre vessels, with ten more electric and hybrid craft currently under construction.

Easy infusion

Diab’s lightweight, industry leading, DNV type approved Divinycell H foam features a unique PVC formulation that delivers impressive mechanical performance for Brodrene AA. Highly resistant to the significant fatigue, slamming and impact loads seen in high speed ferries, Divinycell H also matches the processing requirements at Brodrene AA being easy to machine, thermoformable and with very low resin uptake during the infusion process.

“Our engineers have worked consistently to improve the performance of the foam cores throughout our partnership,” explains Viggo Karlsen, managing director of Diab Norway. “We have reduced component weight at Brodrene AA by supplying tightly toleranced thicknesses that create the smoothest laminates and by evolving our flow and form-based finishes to reduce infusion times.” 

Reduced footprint

Another key focus of the Brodrene AA and Diab partnership is a combined commitment to sustainability. Diab has made significant strides in reducing the carbon footprint of its materials, achieving a 50% reduction between 2016 and 2023. Brodrene AA’s use of durable carbon fibre and foam composites extends the lifespan of its vessels. minimising the need for replacements and reducing overall lifecycle costs.

The Vision of the Fjords, a 100% electric, zero emission hybrid-electric tour vessel received multiple awards including a JEC Innovation Award for its design and environmental impact, whilst the shipyard’s latest projects include the refit of two ferries, MS Baronessen and MS Baronen, to extend their hulls and switch to battery power. This initiative, using Diab cores, will incorporate Norled’s SHIFTR battery replacement technology, allowing for quick battery swaps and enhanced operational efficiency, further exemplifying Brodrene AA’s commitment to circular design and sustainable solutions.

“As we commemorate fifty years of collaboration with Diab, we reflect not only on our shared history but also on what lies ahead,” says Tor Oyvin Aa, CEO, Brodrene AA. “Together, we’ve sailed through challenges, harnessed new composite technologies and navigated the seas of change. As we take on the next half-century, our partnership with Diab remains steadfast and it drives us forward as we pioneer the development of the lightest, cleanest, high-performance ships of the future.”

www.diabgroup.com