ClassNK has granted an expanded Approval in Principle (AiP) to OceanWings covering its Rigid Fixed (RF) and Rigid Tiltable (RT) wingsails. The approval was presented during an official ceremony at SMM in Hamburg on 2 September 2026. The expanded approval confirms the scalability of OceanWings technology across a broad range of vessel sizes and shipping segments.

The decision builds on the initial AiP granted by ClassNK in 2025, which was limited to the 363m² wingsail with a 38-meter span. The new extension confirms that the core design principles of both configurations can be applied to a broad range of wingsail sizes. OceanWings' product offering already includes wingsails of up to 407m² with a 42-meter span, and the technology is now approved to expand to even larger sizes for larger ship segments and different operational profiles.

The two configurations serve different operational needs: the Rigid Fixed wingsail is a stationary rigid profile, while the Rigid Tiltable version can tilt, which aids cargo handling and air-draft management on board. Wind-assisted propulsion of this kind has drawn growing industry attention as shipping seeks to reduce fuel consumption and emissions, including in the context of IMO greenhouse-gas reduction targets for international shipping.

Emmanuel Schalit, CEO of OceanWings, commented: "This expanded Approval in Principle reflects the continued progress of our technology. The design philosophy, control architecture and onboard integration principles remain the same across all wingsail sizes. In practice, the appropriate dimensions are determined by the technical and operational requirements of each vessel, rather than by a predefined size limitation."

According to OceanWings, the expanded AiP gives shipowners, shipyards and naval architects greater confidence when assessing the most appropriate OceanWings size and configuration for their vessels. It also supports earlier integration of wind propulsion into newbuild programmes and retrofit projects. An AiP from a classification society such as ClassNK assesses a design at the concept stage against relevant class rules, providing a documented basis for later detailed design approval rather than certifying an installed system.

Hayato Suga, President & CEO of ClassNK, commented: "As the adoption of wind-assisted propulsion technologies continues to grow across the maritime industry, we are pleased to grant this Approval in Principle for OceanWings' RF and RT wingsail designs. ClassNK will continue to support the maritime industry's transition toward more sustainable shipping through its certification services."

The milestone forms part of OceanWings' continued qualification and industrialisation roadmap, strengthening the company's ability to deploy wind-assisted propulsion for ships globally. The next steps in such a roadmap typically involve detailed design review and class approval of installations on specific vessels.

Source: OceanWings via Hellenic Shipping News