Offshore service ship proceeds astern almost as quickly as bow first

Acta Marine’s service operation vessel Acta Auriga, designed and built by Ulstein Verft in Norway, has completed sea trials demonstrating its unique capability. 

Acta Auriga, a service operation/walk-to-work vessel was custom-designed for the offshore wind and offshore oil and gas industries and is fitted with a 3D crane, SMST gangway and elevator tower and has the X-BOW and X-STERN hull shape. It is only the second vessel with both hull shapes. The ship was designed for safe transfer by motion compensated gangway with cargo lifting functionality up to Hs 3.0 m.

The capability conferred by the X-STERN was evident during trials when it was tested to determine its maximum speed forward and astern. The vessel achieved a speed of more than 12.5 knots in astern mode and registered a speed bow first that exceeded 13.5 knots. 

Deutsche Offshore Consult’s marine operations manager Sebastian Zehmke-Marahrens, whose company is marine advisor to Ocean Breeze Energy, owner and operator of the Bard Offshore 1 windfarm where the vessel will work, said “We believe there will be a tremendous performance advantage with this vessel. It will reduce the time needed to bring the technicians to turbines significantly. This will enable us to access more turbines per day.”

The Ulstein SX195 design has now returned to the yard for completion, before delivery to Acta Marine. The vessel has been awarded a two-year charter for operations and maintenance work on Bard Offshore 1.