DNV greenlights Oceanbird’s wing sail

The first wing sail from Oceanbird, Wing 560, has received Approval in Principle (AiP) from the classification society DNV.


An Approval in Principle is an independent assessment of a concept within an agreed framework, confirming that the design is feasible, and that no significant obstacles, so called showstoppers, exist to prevent the concept from being realized.

DNV have looked into how the wing could handle extreme conditions such as heavy wind loads, snow and ice loads and green sea (waves on deck). They have also investigated redundancies in system functionalities (trimming, reefing, folding, etc.), control systems, the foundation and machinery and electrical component functionalities.

Oceanbird have requested that the review should include documents beyond the minimum requirements to reduce uncertainties related to the concept.

“It is one of the first stiff wing sails that will tilt in hard winds as a safety feature, that gets an Approval in Principle. Therefore, it is reassuring that DNV supports our safety philosophy since we are now going from vision into realization. In just a few months, we will begin to assemble our first full-scale wing prototypes, which will be onboard a vessel in about one year from now,” said Niclas Dahl, Managing Director at Oceanbird.

“We’re pleased to award Oceanbird the AiP for their wind-assisted propulsion system (WAPS). Such systems hold promise in enhancing the efficiency of maritime operations, and partnerships like this play a significant role in moving the industry towards decarbonization,” remarked Hasso Hoffmeister, Senior Principal Engineer at DNV.

“Safety is our first priority and therefore, we wanted DNV to do a comprehensive review of the design,” said Mikael Razola, Technical Director at Oceanbird.

“The good collaboration with DNV has been very important for us. We are confident in our design, and this strengthens us when going into the next step, which is a Type Approval and prototype assembly.”

Oceanbird is a joint venture created by Alfa Laval and Wallenius with the purpose of developing wind propulsion for the shipping industry.

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The 40-meter high and 14-meter wide (560 m2) rigid wing sail from Oceanbird has more in common with airplane wings than traditional sails, according to the company.

Using air pressure to push the vessel forward, one wing sail on an existing vessel could save up 10% of fuel and emissions on optimal routes.  The company said that the prototype will be assembled at the Oresund DryDocks shipyard, Sweden’s largest repair yard, by the fall and placed by the Swedish coastline in Landskrona by the end of 2023.

A vessel that is specially built for sailing with a full set (6) of Oceanbird Wing 560 will be sailing in 2027. 

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