Zephyr Wing-sail Tri

By far the most intriguing craft our judges came across this past year was the new Zephyr trimaran, with a unique sailing rig that makes it look something like a floating hang-glider. This is the brainchild of Tony Smith, well known in the industry as the creator of both the Gemini catamaran and the Telstar trimaran. Smith built this prototype in his garage and is seeking an investor interested in putting this unique vessel into production. The boat’s ingenious rig works on the same basic principle as a simple windsurfer or, more notably, the Vestas Sailrocket, which in 2012 shattered (and still holds) the world speed-sailing record. The boat’s sail, instead of being set on a vertical mast, is canted to windward at an angle to offset the heeling force it generates, with its driving force perfectly opposed to a daggerboard foil underneath the trimaran’s opposite ama. What makes the vessel unique is that, unlike the super-fast Sailrocket, which was designed for straight-line speed runs over short distances and could sail only on one tack, the sail on the Zephyr can be tacked back and forth. This is accomplished via a pair of clever manually driven interconnected hydraulic pistons that hold the sail aloft. When the ram in the windward piston is pulled down, the ram in the leeward piston is automatically extended, which allows the boat’s skipper to easily cant the sail from side to side. One great advantage to the rig is that the sail, as it moves through the wind when tacking, loses none of its driving force. The boat’s controls are also simple and intuitive. You steer with your feet, which leaves your hands free to manage one line that controls the sail’s attack angle and another that cants it back and forth over the hull. Though obviously this project is not yet ready for prime time, our judges were so impressed with the creative thinking behind it they felt compelled to recognize it with this special award. s