---

Civil Aviation Bill

moved Amendment No. 6:"Page 2, line 42, leave out subsection (2)." The noble Lord said: My Lords, I must return once again to the highly controversial issue of night flights. The issue was debated at some length in Grand Committee, and despite the Minister’s assurances I remain unconvinced of the necessity or the wisdom of the change in the present system proposed by Clause 2(2). As noble Lords are aware, aircraft night noise is currently controlled by the combined operation of a movements limit and a noise quota system. Amending Section 78(3)(b) of the Civil Aviation Act 1982 in this way would empower the Secretary of State to discontinue the association of limits on the number of night movements at Heathrow, Gatwick, Stansted and elsewhere. I must declare an interest as leader of Essex County Council and that Stansted airport is situated in that county. The removal of the movements limit and the reliance on the quota count system will have a devastating consequence for the millions of people who live under major airports’ flight paths. The quota system is highly technical and is often incomprehensible to the people it is meant to protect. There is no official index for night noise in the UK. The noise limit is calculated by using Leq, or level equivalent, which is officially recognised during the day between 7 am and 11 pm. That fails to take account of the fact that noise has vastly different implications at night. Level equivalent is a measure of noise energy and is worked out by averaging the noise level over a 16-hour day and expressing that as a continuous level. Its shortcomings are illustrated by the fact that a single Concorde on departure has the equivalent noise energy of 120 Boeing 757s. Thus, a Boeing 757 departing every two minutes for four hours produces the same level equivalent as two minutes of Concorde, followed by three hours and 58 minutes of silence. Under the quota system, all aircraft are rated according to their noise on take-off and approach, and then banded into quota count categories that are three decibels apart on an exponential scale. A limit is then placed on the total number of points in a six-month season. I am explaining this in a technical way, because it is an important element of this issue. The fundamental conceptual flaw behind the way of regulating aircraft noise is the assumption that the degree of disturbance and/or annoyance caused by noise depends only on the level of the overall noise dose in terms of sound energy emitted. This method is perverse, because it fails to take any account at all of the importance of how many and how frequently flights are permitted. The same total noise exposure can be achieved with a few noisy aircraft or a larger number of less noisy ones. Furthermore, whether those aircraft are bunched together or spaced at long intervals during the night period does not make any difference to the noise dose. By removing the night movements limit, the implication is that as aircraft become less noisy, more flights can be accommodated within the same noise quota. Under the quota count system, one Boeing 747, rated as QC2, could be replaced with four Boeing 777s, rated as QC0.5. Less noise does not necessarily mean less disturbance. I repeat, less noise does not mean less disturbance. Consequently, the system is wholly inadequate for assessing the disruption of sleep caused by the impact of a relatively small number of noise events during the night. Cumulatively, those noise events may not break the noise quota, yet they may result in a person being disturbed on multiple occasions during the night. It is imperative that we retain the movements limit on night flights. It is not only effective, but is easily understood, transparent and open to validation. Importantly it provides protection for those people who live in close proximity to airports, but not necessarily under flight paths. It protects them from the associated problems of ground noise, which the quota system alone cannot properly address.