STEALTH ON THE WATER

摘要

An undercover team ot Navy SEALs isn t worth much if their transport boat's wake betrays their approach. Nor does it help if they come ashore with back pain and possible organ damage from the boat's constant bouncing. A sleek new hull design could help troops slip through waves undetected and unscathed, while also setting a new standard for efficient nautical design.rnWhile experimenting with high-speed yacht designs for the America's Cup sailing race, aerospace engineer A. Calderon began investigating ways to reduce the wake that builds around the vessel's bow, sides and stern as it cruises through water and grows as the boat moves faster, increasing drag and draining fuel. The bow of Calderon's concept, called the transonic hull, is shaped like a tight V and cuts through water like a knife, diverting the wake sideways and under the boat to nearly eliminate it altogether. Preliminary tests of a 20-foot wood-and-fiberglass prototype indicate that the model incurs 28 to 38 percent less drag than an ultra-streamlined Americas Cup yacht, which Calderon says could translate to 30 percent better fuel economy than similar boats. And it powered through waves four feet tall without bouncing.