Inflatable Sails By Steve Morrell
Inflated Wing Sails They call it “IWS”—Inflated Wing Sails. The wing sail has been around for a long time, but it became famous after it was first used in the America’s cup by BMW Oracle on their trimaran (which won the cup) in 2010. Wing sails are generally rigid, and can’t change shape like an aircraft wing. They also provide more lift and have a better lift-to-drag-ratio than traditional sails. Now, a team of three in Switzerland has come up with an inflatable wing sail. One of the three, Edouard Kessi, developed the first paragliders, has a history of sail technology and is a known Swiss sailor. He has been working on
inflated wing sails for the last two years. Another member of the team, Laurent de Kalbermatten, came from the world of flying, hanggliding and paragliding, and is considered the father of paragliding. He developed inflatable paragliding wings. It was Kessi and Kalbermatten who did the original development of the system. The third member, Stephane Fauve, has expertise in sail design and sail materials. The original testing of the IWS was done on a laser in 2015. The website describes the system: “IWS is stable in every wind condition. There is no pressure on the boat‘s structure. IWS offers a smooth balanced new way of sailing. No more winches, halyards, shrouds or complex deck equipments.” Videos of sailing with the IWS are on the website, but details of how it all works are not explained. The inflated sail has a retractable mast inside the wing that telescopes up and down. Raising and lowering the sails is done by raising and retracting the mast and inflating and deflating the sails. The sail has an opening on the forward (luff) end of the wing with fans that propel the air in. It is not explained, but I assume it means that mechanical power of
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January 2018
SOUTHWINDS
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