Blanketing Meaning in Sailing

Blanketing occurs when a vessel positions itself to intercept the wind meant for another. This action creates a zone of turbulent or blocked air on the leeward side. The following boat experiences a sudden drop in power as its sails go flat. Racing sailors use this method to pass opponents or defend their current lead position. It requires the leading boat to stay directly between the wind and the competitor. An example happens when a lead boat maneuvers to stay ahead of a chasing ship. The chasing ship slows down immediately because the lead sails take all the energy. This interaction changes the physical pressure on the fabric of the trailing boat sails. To escape this effect the trailing sailor must change course to find clear wind. Recognizing the size of this wind shadow helps a navigator plan a better route.