As we’ve reported recently, continued research and development is going into making aircraft quieter, and often as a by product, more fuel efficient, safer and cheaper.
According to a Wired Report, Heavy Metal Makes Lighter Planes,
Qantas engineer Ian Salmon tested wing sections covered with a piezoelectric material that vibrates when a current is applied to it. When the tone of the sound was at its most effective pitch, Salmon’s wing panel achieved 22 percent more lift than it would have without the piezoelectric hum.
Vibrating wings could be used to make planes safer, reduce wing size and provide another element of control for pilots, Salmon said. But don’t expect the wings on commercial jets to start humming away any time soon. The technique only works well on smaller planes such as light aircraft and military-style unmanned aerial vehicles like the Predator.
Larger aircraft are equipped with advanced sensors and sophisticated trailing-edge flaps, which are used to change the shape of the wing during takeoff and landing. Vibrations could improve these conventional controls, but likely not replace them completely. For example, the greater a wing’s angle to the horizontal, the slower the plane can fly and thus the safer it can land. Vibrations could also eventually help engineers design planes more efficiently.
…It’s all about changing the air flow from an unstable laminar flow to a turbulent flow that increases lift, Cummings said. The vibrations change the way the air behaves when it starts to break away from the wing’s surface, sucking it closer.
