Goal: Dramatically Reduce Aircraft Noise

Listen: Do you hear that sound? No? That's the point. The Cambridge-MIT Institute (CMI) is launching a unique project to design a 'silent' aircraft.

CMI's "Silent Aircraft" project has a bold aim: to discover ways to reduce aircraft noise dramatically, to the point where it would be virtually unnoticeable to people outside the airport perimeter in a typical built-up area.

This initiative is bringing together leading academics from Cambridge University and the Massachusetts Institute of Technology (MIT) with representatives from all parts of the civil aerospace/aviation industry. This unique community will be working together, sharing knowledge and developing the design for an aircraft whose noise emissions would barely be heard above the background noise level in a typical built-up area.

Partners in the project include British Airways, the Civil Aviation Authority, regional aerospace company Marshall of Cambridge, and National Air Traffic Services. They also include Rolls-Royce, which has made available its multi-million pound suite of design and analysis tools to help the research. Additionally, the project team plans to include representatives of community groups opposed to aircraft noise.

Professor Ann Dowling, from Cambridge University's Department of Engineering, is one of the project's leaders.

"The civil aviation industry is already introducing small, incremental decreases in aircraft noise", she says. "But we are aiming for a radical change in noise levels - so that beyond the perimeter of the airport, the noise of aircraft flying would be imperceptible to the public."

Both in the United States and Europe, aircraft noise has been one of the major factors holding back the growth of air transport. Airports that have tried to expand to increase capacity and ease delays have met resistance from local groups, worried about the impact of increased aircraft noise.

The leaders of CMI's 'Silent Aircraft' initiative claim that designing silent aircraft will help overcome this problem, as well as providing a major boost to the UK aerospace industry, and helping UK airlines operate more productively.

Professor Ed Greitzer is the project's leader at MIT. He says, "Although there have been a number of improvements in aircraft design, the overall shape of passenger aircraft has in general not altered a great deal over the last 40 years. A new departure in this project is to start with the idea of having a major decrease in noise as a primary design variable. With this, we envisage consequent major changes in aircraft configuration and operations. 'Silent' aircraft would help meet passenger demand for more flights, by creating opportunities for new airports, and allowing increased operations at existing airports."

CMI's 'Silent Aircraft' initiative is one of four new Knowledge Integration Communities (KICs) that CMI is setting up this autumn. These KICs aim to find new ways in which academia and industry can work together and exchange knowledge to push forward research in areas where UK industry has a demonstrable competitive position - like aerospace. The Silent Aircraft KIC also aims to enhance this position by engaging with youngsters of all ages to enthuse them about aviation, and thus help ensure a continuing supply of talented individuals into the industry in years to come.

In one knowledge exchange initiative, the students on the project team studying aircraft engine design will spend a month seconded to Rolls-Royce at Derby. Staff from Rolls-Royce will then come back to Cambridge to continue the work. They will be using some Rolls-Royce design codes as they undertake a fundamental redesign of the elements of the engine that contribute most to noise.

"This is a bold project to address what is an increasingly acute environmental problem for the civil aviation industry in the UK," said Dr Nigel Birch, Chief of Noise Engineering at Rolls-Royce. "Rolls-Royce is undertaking its own research in aircraft engine noise reduction, but to achieve a very large step change in the performance of aircraft requires a radical integrated approach to the design and operation of future aircraft and flight systems. This was identified by the recent UK Cabinet Office sponsored Aerospace Innovation and Growth team as key to continuing the success of the UK aerospace industry. We believe that the breadth and depth of skills and knowledge available at Cambridge and MIT will be a valuable contribution to research in this area. Crucially, CMI has succeeded in engaging in the project all parties who can actually implement the results of the research in real projects where the gains can be exploited. We are highly committed to this project and look forward to its success."

"We welcome continued research into quieter aircraft technology, and especially the work that aims to optimize operational procedures within capacity constraints, in the context of improving UK competitiveness. Minimizing noise from flight operations is a priority for British Airways, and we look forward to the contribution the project can make towards this goal," Andy Kershaw, Manager of Environmental Affairs for British Airways.

"Environmental factors play an increasingly important part in modern airport operations and noise is a key issue," Iain Young, Chief Test Pilot of Marshall of Cambridge. "A reduction in aircraft noise would make a significant contribution to the development of regional airports through reducing the noise impact on local communities. We are delighted to support this initiative and look forward to participating in an important and interesting program."

(ANN Correspondent Matthew French, based in Turku, Finland, contributed to this story)

FMI: http://silentaircraft.org