Kongsberg Maritime has secured a contract to design and equip four commissioning service operation vessels for IWS Fleet, a subsidiary of Integrated Wind Solutions. Nantong Rainbow Offshore & Engineering Equipment will build the ships in China to Kongsberg’s UT 5519 DEx design, the latest version of its Skywalker class. The first vessel is due for delivery in 2029.
The supplier’s package covers vessel design, electrical power systems, navigation and bridge equipment, propulsion, deck machinery and dynamic positioning. The ships are intended to support offshore wind farm commissioning and maintenance, transporting technicians between turbines while accommodating personnel offshore during longer work periods. Each vessel is designed to accommodate up to 120 people.
A double-ended hull arrangement is combined with four rim-drive azimuth thrusters, fitted in pairs at the forward and aft ends of each ship. Azimuthing propulsion allows thrust to be directed during manoeuvres, while Kongsberg’s dynamic positioning system adjusts the thrusters to maintain position and heading against wind, waves and currents. These functions are particularly relevant when a vessel is holding station near an offshore wind turbine for personnel transfer.
Kongsberg says the rim-drive units use permanent magnet motors to provide responsive propulsion control. Electrical power management, propulsion and bridge functions are included in the same contracted technology package, giving the supplier responsibility for integrating systems that must operate together during transit, manoeuvring and station keeping.
Commissioning service operation vessels act as floating bases for technicians who need repeated access to offshore assets. Their accommodation and working spaces allow crews to remain near a wind farm during inspection, maintenance and commissioning campaigns.
Six Skywalker-class vessels have been delivered since 2023, providing the starting point for the revised design. The four new orders would extend the class to ten ships once deliveries are complete. No contract value or delivery dates for the remaining three vessels have been disclosed. Kongsberg will now work with the Chinese shipyard to integrate the specified equipment into the newbuild programme ahead of the first scheduled delivery in 2029.
