Working To Silence Noisy Airliners

An engineer working with the “Silent Aircraft Initiative” said in Dublin Friday that advanced airliner designs using a blended-wing body could be flying within 20 years, and would create less noise than background traffic levels. Speaking at the British Association for the Advancement of Science’s annual festival, aerospace engineer Tom Reynolds, of the Massachusetts Institute of Technology, said researchers are also experimenting with ways to make current aircraft quieter (which may one day help keep more airports open). Flight tests will start next year to try out a new, steeper landing approach that would limit the amount of time planes spend at low altitudes. “It’s really a win-win from an operational point of view because you get less noise and less fuel burn at low altitude,” Reynolds said. Once the engines are throttled back for landing, about half the noise comes from the flow of air over the airframe, Reynolds said. Some solutions that the team is exploring include putting the engines above the aircraft so the body of the plane itself shields the ground from noise; embedding them in long ducts, muffled with acoustic liners, to reduce the noise; and designing an advanced engine. The Silent Aircraft Initiative is a consortium of researchers from Cambridge University in England and MIT.