VESSEL REVIEW | MO6 & MO7 – Versatile SWATH windfarm support vessels for UK’s Mainprize Offshore

UK-based offshore renewables services provider Mainprize Offshore has placed a new series of aluminium windfarm support vessels (WFSVs) into service.

Designed by Walker Marine Design and built in Vietnam by Shipbuilding Asia, the sister vessels MO6 and MO7 will perform a range of tasks including crew transfer, offshore bunkering, and cargo operations.

Each WFSV has an LOA of 26 metres, a beam of 11 metres, a maximum draught of three metres, a displacement of 165.8 tonnes at full load, and capacity for 24 passengers/technicians and three crewmembers. The SWATH hull form of each vessel will enable transfers of personnel even in wave heights of up to two metres while a significant cargo capacity of up to 50 tonnes is ensured by the 190 square metres of total deck space.

The interior on each boat features fully adjustable suspension seats for the passengers, a mess, a galley, crew cabins, showers, dual toilets, and storage for luggage and spare parts. All onboard spaces have both heating and air conditioning as well as wi-fi and 4G connectivity.

The WFSVs are each powered by two Caterpillar C32 engines that each produce 1,193 kW at 2,300 rpm. The engines drive controllable-pitch propellers via ZF gearboxes to deliver a top speed of 23 knots, a range of 2,500 nautical miles at a cruising speed of 21 knots, and a bollard push of 22 tonnes. Two Caterpillar C2.2 21kW generators are also fitted.

The electronics suite includes Sailor MF/HF and VHF radios, an Asus ECDIS, and a Furuno package consisting of main and auxiliary radars, a compass, GPS, and AIS.

Design work on the new Mainprize Offshore WFSVs was done in compliance to Bureau Veritas class rules.