Shipping contributes substantially to global greenhouse gas emissions. Efforts to reduce these emissions are being made everywhere at many levels, with sail (auxiliary) propulsion systems in particular experiencing a renaissance. As part of its maritime research program, the German Federal Ministry of Economics and Climate Protection is now for the first time funding a project to optimise additional wind propulsion systems on board merchant ships, specifically Flettner rotors. On the basis of numerical and experimental models, the new FlettnerFLEET project is developing largely improved design principles for the integration of additional wind propulsion in modern merchant ships, both for newbulidings as well as retrofits. In addition, the design and operation of the rotors are also being optimised. Within the framework of the joint project led by MARIKO GmbH, HSVA will carry out the aero- and hydrodynamic investigations and developments for optimised wind ships and thus further establish the topic of wind propulsion as a new mainstay at HSVA. Detailed information on the FlettnerFLEET project can be found in the press release, e.g. at Greenshipping-Niedersachsen or Hansa-Online.