Aircraft Noise Limits (Hansard, 18 December 2000)

§ Mr. Mullin

On 24 November 1997 the Department of the Environment, Transport and the Regions published a new consultation paper proposing lower noise limits and improved monitoring arrangements. This consultation followed the Court Order of 16 April 1997, made after challenges by the International Air Transport Association (IATA) to the 1996 decision on this subject. The Order, made with the consent of the parties, enabled interim arrangements to be put in place until the outcome of the new consultation. The November 1997 paper was also challenged by IATA but the association withdrew its application for leave to apply for judicial review when the Department undertook to publish a supplementary consultation paper. That was done on 26 March 1999. All the proposals were unchanged. They were:

(a) to relate the noise limits to a fixed reference distance, 6.5 km from start of roll;
(b) to continue to monitor noise levels at the fixed monitors in L_max dBA and to apply the noise limits to all departing aircraft except Concorde and a number of specified exemptions (see (h));
(c) to reduce the noise limits by 3 dBA (daytime) and 2 dBA (night-time), to 94 dBA and 87 dBA respectively;
(d) to retain the five monitors at Gatwick and eight monitors at Stansted currently operating under the interim arrangement, but to resite a Stansted monitor to a better position. At Heathrow to keep the eight sites in the interim arrangements and to add two further monitors as previously proposed;
(e) to calculate the positional adjustments on a revised basis;
(f) to allow a reduction of not more than 2 dB of the noise recorded in specified tail wind conditions;
(g) to require aircraft to be at a height of 1000 ft aal at 6.5 km from start of roll;
(h) to exempt from the new daytime noise limits certain aircraft given exemptions from the Chapter 2 phase out requirements in accordance with the provisions of the EC Directive;
(i) to begin a further review of both monitoring efficiency and noise limits in 2000.

Comments were invited on any aspect of the proposals and on the details covered in the supplementary paper. The closing date for responses was 4 June 1999. Taking account of the information and comments we received, we have decided to implement the proposals, with two modifications:

(a) to reduce the night-time noise limit by 2 dB, to 87 dba as proposed, but to apply it only during the night quota period (2330–0600), retaining the present night-time limit (89 dBA) for the rest of the night period, 2300–2330 and 0600–0700;
(b) to implement the new daytime noise limit of 94 dBA from 25 February 2001 but to implement the new night-time noise limit from the start of the next summer night restrictions season (ie from 25 March 2001), rather than between 2–3 months from the date of the decision announcement, as was indicated in the consultation paper.

Also, for technical reasons, for the purpose of the tailwind allowance I have decided to use wind data from an alternative source to that described in the consultation 12W paper. I am satisfied that it is appropriate to use data from the on-airfield anemometers and wind vanes in the formula for the tailwind allowance proposed in the consultation paper (i.e. without making it necessary to adjust the formula).

The reduction of 3 dB in the daytime limit represents a halving of noise energy but only a small reduction in loudness. This is a long accepted scientific fact; it is not disputed in the responses. The cumulative effect of even small improvements should be of benefit to many local residents, particularly those living under the departure routes from about 6.5 km from start of roll out to about 15 km. These small improvements will occur whenever an aircraft flies overhead that has changed its procedures (or adopted other measures) to meet the new noise limits.

Some major airlines consider they will incur disproportionate costs to achieve these small benefits; conversely, many of the local authorities and other groups representing those living around the airports consider there should be greater noise reductions, to give greater benefits. I am satisfied that the requirements announced today are reasonable, having regard to what is operationally achievable (as explained in the consultation paper), to the costs that may be incurred by some airlines, the benefits that will accrue to many local residents, as I have already indicated, and the disbenefits that will be caused to others, particularly the far smaller number of people living very close to the end of a runway. Operators of heavily laden services bound for Asia-Pacific destinations that are scheduled to take off in the late evening, which would have particular difficulty in meeting the new night-time noise limit if delayed beyond 2300 hours, should be able to plan their operations with greater certainty in the light of our decision not to apply the toughest limit until 2330. I should emphasise that I do not want to encourage late departures. On the contrary, I trust operators of these services will continue to do their best to minimise delays: that will be of benefit both to their customers and to local people.

The full decision, and the reasons for it, are set out in the document 'Noise limits for aircraft departing from Heathrow, Gatwick and Stansted airports: decision of December 2000' copies of which have been placed in the House Library.

Copies of all the responses, excepting details for which the author has requested confidentiality, are available for inspection by prior appointment at the DETR Library and Information Centre, Ashdown House, 123 Victoria Street, London SW1E 6DF.