VESSEL REVIEW | NR Predator – UK fast catamaran crewboat built for year-round operations

UK offshore support company NR Marine Services has taken delivery of a new catamaran crewboat built by Isle of Wight-based Diverse Marine. Named NR Predator, the vessel boasts a hull form that incorporates an ultra-fine entry for excellent head sea performance and tower access but with high reserves of buoyancy above the main chine. This allows for equally good following and stern quarter seakeeping performance.

The new crewboat has an LOA of 27.6 metres (90.6 feet), a beam of 9.8 metres (32 feet), a draught of 2.4 metres (7.9 feet), a depth of five metres (16 feet), and space for 24 technicians and four crewmembers. A 100-square-metre (1,100-square-foot) open deck can carry two 10-foot containers or cargo totalling 30 tonnes. The open deck also has a crane and a dedicated area for dangerous goods.

"We only had summer campaign vessels in our fleet capable of carrying 12 passengers with the largest vessel being 21 metres (69 feet) long," Owen Nutt, Director of NR Marine Services, told Baird Maritime. "In late 2022 we saw the rise in requirements for future 27-metre (89-foot), 24-passenger vessels and we knew that for our business to move forward, we would need to invest and order a larger vessel to keep up with our clients' demands. The idea behind the vessel was for our company to gain a longer-term, all-year-round charter."

In early 2023, the order was placed with Diverse Marine. A year later, NR Predator was delivered and went into operation shortly afterwards.

Highly efficient and versatile design

"It is the first of a new class of crewboat developed with the possibility of achieving net zero emissions and high operating efficiencies, all at minimum risk to the operator and the end client," added Diverse Marine. "We had a requirement to install a quad Volvo Penta IPS propulsion package with a given power output, though existing craft are marginal in terms of performance and the challenge was to increase vessel performance and reduce fuel consumption and emissions."

Diverse Marine said it worked closely with NR Marine Services, the designer, as well as operators, to refine the hull design by changing the lower chine concept and reducing hydrodynamic drag by 18 per cent at peak and 11 per cent at operational speeds. In the builder's view, the result is a fast and efficient vessel demonstrating very low fuel consumption at higher speeds compared to similar craft, as well as high levels of turbine access availability.

"The vessel is operated with quad Volvo IPS 1050 IMO Tier III propulsion offering speeds of up to 28 knots whilst around half the fuel consumption of comparable size vessels," added Nutt. "The vessel can also transfer personnel safely to turbines in wave heights of 1.75 metres (18.3 feet) and above."

Specifically, the quad Volvo IPS 1050 arrangement provides more power for turbine push-ons whilst ensuring lower power requirements for normal sailing, which in turn means the engines need not work as hard. According to Nutt, the vessel can make 12 litres (2.6 gallons) per nautical mile at an average speed of 29.1 knots. The crewboat also features a monitoring system that measures vessel performance, speeds, fuel consumption, turbine impacts, motion, and CO2 consumption.

"The in-built accelerometers and motion sensors learn the vessel's behaviours and use artificial intelligence to inform the master of the optimum service speed for given conditions," said Diverse Marine. "This is to ensure that during operation, the technicians are in the safest possible environment."

First in a new series

For Diverse Marine, building any first of class vessel presents challenges in the connection between design and production. All stakeholders thus need to work towards producing the best possible vessel that evolves at each stage whilst ensuring costs and lead time are still achieved without any compromise to quality or performance.

"NR Predator starts the run of eight further builds that use the same propulsion and components," Diverse Marine told Baird Maritime. "A great deal of effort went into this crewboat to ensure all services were optimised for reliability and accessibility so that all the vessels in the series can be easily maintained."

NR Predator is currently chartered at the East Anglia One wind farm, taking technicians out daily from the port of Lowestoft. The vessel is chartered until late July then will be available afterwards for long-term charter.