If you’ve ever built a model airplane using components cut from balsa, you’ll know what’s involved in constructing an AC45 wingsail. The process is very similar. First you cut out the parts, then you painstaking assemble them into the framework of the wing, then you apply the skin material and shrink it to a tight fit. Here, aerofoil-shaped wingsail ribs, cut from carbon fiber/Nomex honeycomb sheets by a CNC machine, await assembly.
Photo by Peter Nielsen