New Hull Form Offers Better Handling at High Speed

By The Maritime Executive 2017-03-23 19:18:03

The U.S. market for RIBs has a new, innovative entrant – the Rafnar "ÖK Hull," which appears to offer improved seakeeping and handling characteristics.

The patented "ÖK" design is a displacement hull, but Rafnar says that it behaves more like a semi-displacement vessel in terms of speed and handling. The firm's rescue-boat models are capable of 40 knots, and videos of vessel boarding tests (above) suggest an uncanny degree of stability in rough conditions. Rafnar says that the hull’s ability to slice through waves and its unusual keel shape are responsible for the design's combination of handling characteristics. 

"It has a deep, symmetrical keel. It does not make a bow wave," explained inventor and founder Ossur Kristinsson in an interview last year. "This boat should have a maximum speed of less than ten knots, but it reaches 40 knots."

The boats also offer a high degree of crew comfort when compared to conventional models. The University of Iceland conducted tests on Rafnar's Stefnir RIB in the North Sea in January, and found that the design reduced hazardous levels of slamming by up to 95 percent (six instances, versus 112 on a standard rescue boat). 

Rafnar is looking for government sales in the North American market, but it also sees its boats as a great option for civilian yacht owners, harbor pilots and tour operators. The firm displayed an outboard-powered 36-foot cabin RIB at the Miami International Boat Show, and the vessel is going on to a tour of the U.S. and the Virgin Islands through April. Later in the year, it will head to Norfolk for a series of demonstrations for government and military agencies. 

Rafnar also offers two more models: a scaled-down 28-foot RIB with a Volvo Penta diesel inboard, which is intended for launch from a coast guard patrol vessel for rapid response; and a 39-foot model with twin Volvo Penta inboards for use as a yacht support craft. Rumor has it that the company is considering a 125-foot expedition yacht design as well. 

The opinions expressed herein are the author's and not necessarily those of The Maritime Executive.