Congested skies

The front page of my Times this morning has a particularly striking picture of an aircraft seemingly about to land on the roof of some unsuspecting person’s three-bedroom semi detached. And contained with the article is a classic example of externalities and costs and benefits. The story is about a proposed reorganisation of holding stacks for aircraft using many of Britain’s busiest airports.

‘Thousands of homes in rural areas will be blighted by aircraft noise under the biggest reorganisation of flight paths, which is intended to cope with the rapid growth in air travel .... National Air Traffic Services (Nats), which manages Britain’s airspace, is planning to redirect aircraft over sparsely populated countryside to reduce the impact on urban areas. The skies above us are increasingly congested as the the number of take-offs and landings at British airports increased from 701,000 in 1975 to 2.4 million in 2006. Controllers guided 2,470,940 aircraft through UK controlled airspace in 2007 compared to 2,386,105 for 2006 – a rise of 3.6 per cent. Worse is to come with a forecast doubling of air traffic volumes between now and 2030.

Reorganisation of air traffic holding stacks threatens increased noise pollution for some but benefits for others including a reduction in the deadweight loss of time spent by aircraft delayed in stacks before starting their final descent. Are there net gains in social welfare from the move? Clearly the more congested are the skies, the more difficult is the trade off between the interests of airlines and their passengers and the disruption to the lives of people living below them.

It is all part of the wider debate about the external costs and benefits of aviation and whether or not airlines should be brought into the emissions trading system or should face further government intervention in the form of higher pollution taxes. And these are not the onlypossible interventions that are on the table.

NATs has already established environmental targets. They aim to cut the emissions of aircraft under its control by an average of ten per cent per flight by 2020.

‘Under the plan, flights departing from Luton will pass directly over the Chilterns Area of Outstanding Natural Beauty, bringing aircraft noise to dozens of previously tranquil villages. But several towns at present blighted by noise, including Hatfield, Hitchin, Princes Risborough, Southend, Sudbury and Royston, may have fewer aircraft passing over them at low levels. The the number of people affected by 57 decibels, which the Government considers to cause significant disturbance, will more than double near Luton and will increase by 11 per cent near London City and 9 per cent near Stansted. Nats estimates that the changes will reduce delays to airline passengers by four million person-hours between 2009 and 2014. However, when averaged out over all the people flying in those five years, it equates to 22.5 seconds saved per person.’

The rest of the times article is here

For more on sustainability issues in the UK airline industry go to this site Sustainable aviation