Silent Aircraft Initiative

The Cambridge-MIT Institute is delighted to announce that sound and vibration measurement company Brüel & Kjær, is joining its ‘Silent’ Aircraft Initiative.

This initiative brings together leading academics from Cambridge University and the Massachusetts Institute of Technology (MIT) with representatives from all parts of the civil aerospace/aviation industry to develop the design for a plane that is radically quieter than current passenger aircraft.

Brüel & Kjær, which for more than sixty years has been an industry pioneer in sound and vibration measurement, will be helping project researchers working in the open jet wind tunnel at the Whittle Laboratory in Cambridge. The company is supplying specialist equipment and knowledge to ‘Silent’ Aircraft researchers Dr. Ho-Chul Shin and Andrew Faszer to enable them to use beamforming and acoustic holography techniques to measure and analyse the trailing-edge noise that will come from the wing of the concept aircraft. 

Faszer is also experimenting with new drag-inducing devices, made out of different types of mesh, which can slow the ‘silent’ aircraft down on its approach to an airport without generating the noise levels associated with conventional aircraft. Precision noise measurements will be run on these devices, using Brüel & Kjær equipment and their acoustic specialists, to see how much drag they actually induce, and to compare their noise performance to that of conventional devices.

CMI’s ‘Silent’ Aircraft Initiative aims to discover ways to dramatically reduce aircraft noise, to the point where it would be virtually unnoticeable to people outside the airport perimeter in a typical built-up area.

It has an increasing Knowledge Integration Community of partners who are working together – organisations that have joined in recent months include Boeing, Cranfield University, London Luton Airport. The newest partner, Brüel & Kjær, serves a number of industries, including automotive and aerospace, and has been in the business of airport noise monitoring for over 30 years. Its noise monitoring solutions have been installed in over 200 airports all around the world, from Norway to New York to Osaka.

“Brüel & Kjær is delighted to be invited to participate in such a prestigious international project which may have a huge impact on the future of commercial aviation,” says William Egan, Director of Brüel & Kjær UK. “Together with such world-renowned institutions as Cambridge University and MIT, we look forward to using our combined innovative skills to stretch the boundaries of science”.

Wim Buyens, Aerospace & Defence Director of Brüel & Kjær, adds, “Innovation drives the aerospace industry so working on the acoustics of the future generation of aircraft is a key factor for Brüel & Kjær. Increasing the quality of people’s lives is part of our mission. Exterior aircraft noise is a vital element in the growing demand for global mobility and we are delighted be involved in this exciting project.”

Researcher Andrew Faszer says: “As trailing-edge noise is the smallest element of noise produced by an aircraft, and is very low-level, it is hard to measure it. However we need to be able to do so, as it will set the benchmark for the minimum level of noise that the ‘silent’ aircraft will produce. Our collaboration with Brüel & Kjær, and the experiment we will be running with their equipment and expertise, will help us gain this necessary insight and understanding.”

As well as producing the concept design for a quiet plane of the future, researchers working on CMI’s ‘Silent’ Aircraft Initiative are also focusing on ways in which noise from in-service aircraft can be reduced. Brüel & Kjær will be joining forces with Marshalls Airport in Cambridge, another partner in the project, to run tests measuring noise radiating from existing aircraft – and thus help understanding how noise disturbance could be minimised. These tests will be taking place during Spring 2005.    

Dr. Ho-Chul Shin says, “Previously, the sheer physical size of an aircraft has made it difficult to co-ordinate all the equipment necessary to measure precisely the noise generated during a test run. However Brüel & Kjær’s commitment to the project will now make the measurements more efficient and easier to do, as they will be supplying their precision equipment and technical expertise.”