Everyone who works with jet engines knows just how loud they can be-- and how much fuel they eat up. Engineers at Ducommun Miltec in Huntsville, Alabama have worked out a system for converting that sound into energy. The discovery came while the engineers were working on the age-old problem of how to make jet engines quieter. Speaking to Discovery News, research engineer Stephen Horowitz explained that their solution was to make a sensitive piezoelectric membrane that turns sound vibrations into electricity. This sensor can then be attached to a special lining that cancels out noise frequencies. Reducing the noise of jet engines has been a focus of private companies, NASA, and other government agencies for years. Hearing damage to aviation personnel, and the noise pollution that impacts people living under flight paths or near airports, could be significantly reduced with quieter engines. Read the full article here.