Classification society DNV has awarded an AiP to Michelin for their WISAMO wing sail system. This is the first AiP to have been awarded to an inflatable wing sail design and is currently being installed for testing on the DNV classed MN Pélican.     
First introduced in 2021, the WISAMO sail is an inflatable, retractable, automated wing sail which can be installed on commercial vessels and pleasure boats. The sail is automated with a system developed by Michelin R&D and is retractable for access into ports and under bridges. The AiP has been awarded based on DNV’s WAPS ST-0511 standard.
The initial tests of a WISAMO sail were carried out on a sailing yacht. Currently installation of a 100m2 system in being undertaken on the DNV classed MN Pelican. The 155m long, 8,600 dwt Compagnie Maritime Nantaise ro-ro cargo vessel, operates under charter to Brittany Ferries and sails between Poole, Great Britain and Bilbao, Spain. This will allow testing of the system under commercial maritime navigation conditions.
DNV’s WAPS ST-0511 standard provides a framework for the verification and certification of wind assistance propulsion systems. It can be applied in obtaining an Approval in Principle, a Design Approval or a Type approval. These verifications and certifications can also be obtained as part of the integration into a vessel or independently. The ST-0511 technical standard is a complement to the DNV WAPS class notation, which is focussed on the integration of systems onboard vessels, whether retrofitted or as part of a newbuilding.
An Approval in Principle is an independent assessment of a concept within an agreed framework, confirming that the design is feasible, and no significant obstacles exist to prevent the concept from being realized. The AIP is typically carried out at an early stage of a project to confirm its feasibility towards the project team itself, company management, external investors or future regulators.
DNV is also member of the International Windship Association and aims to use its membership to further support and accelerate the uptake of wind-assisted propulsion systems by the global shipping fleet.