[holding answer 15 December 2008]: In 2003, “The Future of Air Transport” White Paper set out a strategic framework for the development of airport capacity in the United Kingdom over the next 30 years. In it we said that our basic aim is to limit and where possible reduce the number of people in the UK significantly affected by aircraft noise.
Prior to entry into service, the noise levels generated by any aircraft design are measured by the applicant/manufacturer and then approved by a certificating authority. With regard to the UK, the approving authority is the European Aviation Safety Organisation (EASA), except for light propeller aircraft and microlights where the UK Civil Aviation Authority (CAA) retains responsibility. Certification noise limits are set by the International Civil Aviation Organisation (ICAO). The most recent ‘Chapter 4’ noise limits for large aircraft were introduced on the 1 January 2006.
The Department for Transport is responsible for specific noise mitigation measures at Heathrow, Gatwick and Stansted airports. These include noise preferential departure routes, noise departure limits for both day and night with, additionally, strict limits of movements and a quota system—to encourage use of quieter aircraft—at night.
At other UK airports, noise restrictions may be imposed voluntarily by the airport operator or by local planning conditions/agreements and these will vary depending on local circumstances.
In terms of measuring noise, aircraft noise contours for Heathrow, Gatwick and Stansted using the Leq metric are produced annually for the Department by the CAA. Elsewhere in the UK, it is the responsibility of airports to produce aircraft noise contours as appropriate.
Under the European Environmental Noise Directive 2002/49/EC, all major airports in the UK have been required to produce noise maps for 2006, based on the Lden metric. The directive also requires airports to publish action plans designed to manage noise issues and effects arising from aircraft departing from and arriving at their airport, including noise reduction if necessary. Implementation of the directive in England is a matter for the Department for Environment, Food and Rural Affairs (DEFRA) and in Scotland, Wales and Northern Ireland it is the responsibility of the devolved Administrations.
Given the difference in parameters, caution should be exercised in attempting any comparison between Leq aircraft noise contour maps and aircraft noise contour maps produced in accordance with the Environmental Noise Directive.