New Report Accuses Government of Bias in the Way it Measures Aircraft Noise

Department for Transport accused of a Del Boy approach to noise measurement

  • Under the way the Department measures noise, one Concorde is the equivalent of 120 Boeing 757s.
  • This means, now Concorde has retired, 120 extra Boeing 757s a day could use Heathrow without changing the noise contour.

A major new report from HACAN ClearSkies (1) reveals the extent to which government figures underestimate aircraft noise. The Quiet Con alleges that the Department of Transport is preparing for airport expansion in the forthcoming Aviation White Paper in the full knowledge that the way it calculates aircraft noise is misleading.

The Quiet Con reveals that, when measuring noise, the Department for Transport:

  • Gives undue weight to the noise of each aircraft passing overhead and not enough weight to the number of planes. This means that, under the Department’s calculations, one Concorde is the equivalent of 120 Boeing 757s. The report argues that for most people, “four hours worth of non-stop Boeing 757s at a rate of one every two minutes is very much worse to have to endure than one extremely loud Concorde, followed by 3 hours 58 minutes relief.”

  • Doesn’t reflect the real level of noise people experience when a plane passes overhead. This is because the Department includes the quiet times of the day, and the quiet days of the year, when averaging out the noise.

  • Refuses to measure low-frequency noise — the rumble and roar of an aircraft. The report’s researchers found that, when low-frequency noise is taken into account, a plane passing overhead can be around 8 decibels louder.

  • Underestimates the level at which people start to get annoyed by aircraft noise. The Department for Transport argues that ‘the onset of community annoyance’ sets in when noise averages out at 57 decibels. This would mean that, in the Department’s eyes, aircraft noise is not a problem in places such as Putney, Fulham and Battersea. The World Health Organisation maintains that annoyance starts at around 50 decibels and serious annoyance at 54 decibels.

HACAN ClearSkies argues that the Department for Transport is likely to be in breach of the EU Noise Directive if it does not alter the way it measures noise (2).

The Quiet Con makes a number of recommendations (3). These include adopting the approach used in Sydney. In addition to averaging out noise, the Sydney authorities produce maps showing the actual noise level of planes along the flight path together with figures of the number of planes passing over any one area.

John Stewart, the Chair of HACAN ClearSkies, said, “The Department for Transport has a Del Boy approach to measuring aircraft noise. Our report shows that its methods are flawed and biased. But they give the impression that Government wants to get across: that the noise climate is better than it really is. The Aviation White Paper, which may propose a 3rd runway at Heathrow, will be fatally flawed unless the Department begins to measure aircraft noise accurately.”

Notes for Editors

  1. The report, The Quiet Con, was produced by HACAN ClearSkies with the assistance of FANG (the Federation of Aircraft Noise Groups) and the UK Noise Association. It was written by Richard Hendin, a former pilot with the Royal Navy, with technical input from Dr David Manley BSc Hons, F InstP, MIEE, MIOA, an independent acoustician and expert in low-freqency noise.

  2. See report’s summary for more details.

  3. Key recommendations are listed in the summary of the report.

For further information contact John Stewart on 0207 737 6641 or 07957 385650.