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Taking into account the potential constraints on expansion: three tests for the Airports Commission’s Interim Report

The Airports Commission’s Interim Report will most likely conclude that additional runway capacity is required in the South East, and so for many, the focus should now turn to which of the shortlisted options is best. Yet, in Sir Howard Davies’ ‘Emerging Thinking’ speech and throughout the calls for evidence, the Commission has emphasised that a ‘predict and provide’ model of airport capacity would be insufficient, and that the scale of capacity needed must be assessed within the context of environmental limits and social considerations that “takes into account the potential constraints on expansion”[1]. But will the Interim Report deliver such an assessment?

Below, we pose three tests against which the Airports Commission’s Interim Report should be judged when it is released on the 17th December.  We ask interested parties to conclude for themselves whether the Interim Report passes these tests and delivers a well based analysis of the potential constraints on expansion, or simply provides the infrastructure the industry claims is necessary.


First Test: Does the Commission demonstrate a pathway to meet our national climate change target in a one or two new runways scenario using realistic assumptions?

  • In his October speech Sir Howard recognised the advice of the Committee on Climate Change. This Committee estimated using ‘likely’ improvements in technology and operations that a 60% growth in passenger numbers over 2005 levels would not compromise the UK’s emissions target. There is already sufficient space in existing runway capacity to accommodate this growth[ii].
  • This means building and using one new runway would require capacity limitations on existing airports in the South East and the rest of the UK if we are to meet our national emissions target[iii].
  • The use of a second runway would be dependent on ‘speculative’[iv] technology improvements and a heavy reliance on alternative fuels if the UK is to have any chance of meeting climate targets.


Second Test: Does the Airports Commission only shortlist options that will not worsen the quality of life for communities around airports?

  • Aircraft noise is the main driver of community opposition to airport expansion and is an unacceptable burden on many people living close to airports. Nearly ¾ million people already live within the EU contour of noise annoyance at Heathrow[v], a third of the total number of people affected by aircraft noise across the entire EU.
  • Airports likely to be shortlisted, such as Heathrow, are close to and often breach EU limit values on air quality introduced to protect public health[vi].
  • Both air pollution and aircraft noise pose risks to public health. Air pollution is estimated to cause 29,000 deaths a year and costs the economy £16 billion each year[vii]. A recent study found that people living in areas around Heathrow with the most aircraft noise were 10-20% more likely to have heart problems and suffer from strokes[viii].


Third Test: In light of extensive challenges to the assumptions of economic benefits of expansion and recommendations by a well known economic consultancy firm[ix], does the Airports Commission commit to carrying out a Social Cost Benefit Analysis of each of the shortlisted proposals over the course of 2014?

  • The economic benefits of airport expansion are frequently highlighted in the media at the expense of wider economic and social costs.
  • Each shortlisted proposal should be assessed against a “no new runways” benchmark. Given sufficient capacity exists, it is important to only to consider the additional benefits of funding a new runway.[x]

[i] Quote taken from Sir Howard Davies’ speech ‘Emerging thinking: aviation capacity in the UK’ made at the Centre for London on the 7th October 2013

[ii] In 2011 AEF and WWF carried out research to examine how much growth in passengers and number of movements is possible within existing airport capacity when an aviation carbon target is in place. ‘Available UK airport capacity under a 2050 CO2 target for the aviation sector’ is available from:

[iii] AEF and seven other environmental NGOs recommended this to the Airports Commission in an open letter to Sir Howard Davies’ speech on 7 October available online from:

[iv] The Committee on Climate Change defines the speculative scenario as very unlikely. The scenario requires technological breakthroughs and a significant increase in the pace of aircraft fuel efficiency improvements. In addition, it would require the development of sustainable biofuels which are speculative, such as algae, or developments in land use so that biofuels can be grown at a large scale.

[v] EU noise annoyance contour is 55 Lden. A definition of Lden can be found on the CAA website: The actual figure around Heathrow is 725,500 as used in the Airports Commission Discussion paper on noise.

[vi] In 2012, Heathrow breached the annual NO2 limit at the measuring station within the airport compound. Levels of PM10 also breached legal limits on eight separate periods around the Heathrow area. More information is available in the Heathrow Airport air quality review for 2012:

[vii] These figures are taken from the Defra webpage on ‘Protecting and enhancing our urban and natural environment to improve public health and wellbeing’.

[viii] The study was carried out by Kings and Imperial College London. The press release is available here:

[ix] CE Delft released a report in March 2013 titled ‘The Economics of Airport Expansion’. Available from:

[x] Under DfT’s 2013 central forecast, the unconstrained passenger demand will be 320 mppa in unconstrained compared to 315 mppa constrained which would only squeeze out 1.6% of growth forecasted. DfT figures are available from: