Kenworth is working with an Olympia, Wash.-based company called Aero Works, which has designed a new approach to "boat tails" -- a term that refers to a device that evens out airflow behind a trailer. "The industry has known about the concept for years, but no one has figured out how to make it work and make it marketable," said Wayne Simons, engineering manager for Kenworth's advanced concepts team located at the company's R&D lab in Renton, Wash. "Aero Works might change all that. Our testing has shown that their concept boat tail can improve fuel economy by several percent. For tractor-trailer aerodynamics that's huge and the fuel savings potential is tremendous." According to Lee Telnack, president of Aero Works, he approached Kenworth with his design because of the company's accomplishments. "Kenworth is the known leader in truck aerodynamics and they're very progressive," he said. "I approached them with my idea and design and they were interested in working with us to test our concept. We tested scale models at the University of Washington Wind Tunnel and the results were promising. This led to full-size prototype fuel economy road tests. All told, it's been a great working relationship." Once inflated and rigid, Telnack says his boat tail looks like half an egg that is tapering -- it juts out five feet beyond the back of the trailer. It's designed within the parameters of U.S. Department of Transportation length restrictions for aerodynamic devices.