The Department for Transport produces annual ‘daytime’ aircraft noise contours (16 Hour 57dBA Leq) for Heathrow, Gatwick and Stansted—these airports have been designated for noise control purposes under section 80 and section 78 of the Civil Aviation Act 1982. Elsewhere it is the responsibility of the airport operator to decide upon the timing and form of any contours.
Information on noise contours around Heathrow, Gatwick and Stansted for 2005 to 2007 is available on the Department's website:
http://www.dft.gov.uk/pgr/aviation/environmentalissues/nec/
The 2008 contours are expected to be published shortly.
Information about future projections is available in ERCD 0705 ‘Revised Future Aircraft Noise Exposure Estimates for Heathrow Airport’—also available on the Department's website. Additionally ERCD 0308 ‘Revised Future Aircraft Noise Exposure Estimates for UK Airports’—published at the time of ‘The Future of Air Transport’ White Paper in 2003—contained future projections for Stansted.
In terms of night time contours, the current night flying restrictions regime at Heathrow, Gatwick and Stansted set the following specific noise abatement objectives for each airport:
At Heathrow, to limit the 6.5 hour 48 dBA Leq contour (the winter and summer seasons combined) to 55 sq km by 2011-12;
At Stansted, to limit the 6.5 hour 48 dBA Leq contour (the winter and summer seasons combined) to 38 sq km by 2011-12.
As regards other airports, the European Environmental Noise Directive 2002/49/EC, (END) requires member states to produce strategic noise maps every five years for major airports (with 50,000 and above movements). The maps are required to represent annual average noise values and use of four different parameters daytime (7 am to 7 pm); evening (7 pm to 11 pm); night (11 pm to 7 am) as well as an estimated annual 24-hour period. The range of contours extend—in five dB steps—for 50 to 70 dBA. Airports produced noise maps for 2007 and these are available on the Department for Environment, Food and Rural Affairs' noise mapping website:
http://services.defra.gov.uk/wps/portal/noise