OECD Observer
Towards a greener flight path

On a single busy day in the summer of 2007, 3.2 million people took to the skies above Europe in 33,000 flights which covered a total distance of 34 million km. That’s 42 billion passenger kilometres generated in just one day of European air traffic movements.

Impressive though these numbers appear, they are in fact expected to double shortly after 2025, assuming that the demand forecasts hold true and that the capacity issues across the European air traffic system are solved.

What is the likely environmental impact of all this? At this stage, we are not completely sure, but clearly it is difficult to imagine the impact falling by then. However, there is no reason why it should increase at the same rate as demand.

In other words, we anticipate a steady decoupling of environmental impact from traffic growth. This will be achieved through technical, operational and economic measures which, together, can deliver substantial improvements in aviation’s environmental performance.

EUROCONTROL, the European Organisation for the Safety of Air Navigation, based in Brussels, has been charged by its 38 member states with finding operational solutions that will contribute to reducing noise and local air quality impacts around airports and the reduction of gaseous emissions that contribute to global warming. Although noise and air quality are issues of vital importance locally, aviation’s focus is increasingly influenced by concerns over its contribution to climate change.

The contribution of air traffic management (ATM) comes through ensuring that aircrafts fly at their optimum flight level and over the shortest distance between airports so that fuel burn and CO2 emissions are kept to an absolute minimum.

The target that we have set ourselves is to deliver a 10% reduction in emissions per flight by 2020. This complements the technological push to deliver airframe and engine technologies that, by 2020, will together deliver a 40% reduction in emissions from a new production aircraft.

Flying within an enhanced ATM system, such an aircraft would emit 50% fewer emissions than it would have 20 years previously, thereby meeting the target set by the Advisory Council on Aeronautics in Europe in 2000.

The key programmes to achieve this overall goal for the air transport system are the Single European Sky Research Programme being driven forward by the European Commission, EUROCONTROL and industry to improve the European air traffic management system, and the “Clean Sky” Joint Technology Initiative funded by the Commission to stimulate the research and development required to deliver mature airframe and engine technologies.

A lot has been done. The efficiency of the pan-European ATM system has been systematically improved over the last 15 years, handling more and more flights while maintaining safety and delay parameters within strict limits. These enhancements have delivered environmental benefits, principally through more efficient flight profiles.

The introduction of EUROCONTROL’s Central Flow Management Unit has substantially improved the organisation of the flow of traffic across the system and, by holding aircrafts at the departure gate until airspace is available for an entire flight, has avoided en-route delays and the unnecessary generation of CO2 emissions.

The introduction of six new flight levels in 2002 and the move towards a more dynamic management of European airspace, especially through the effective management of military and civil users’ needs, have improved capacity, safety and environmental performance across the board.

In May 2007, EUROCONTROL, acting upon a recommendation of its independent Performance Review Commission, set itself the target of reducing the average additional flight distance of 49km by 2km annually for the period 2007-11.

EUROCONTROL is also leading work to implement so-called Continuous Descent Approaches, to avoid segments of level flight in the vicinity of airports. This reduces noise, fuel burn and the release of emissions. It is also looking at improving flight profiles on departure tracks to reduce noise, and in the climb phase to reduce fuel burn and emissions. Overall, EUROCONTROL estimates that its ATM efficiency measures have already reduced gaseous emissions by some 3.4 million tonnes per year–that’s 1.1 million tonnes of fuel–with at least a further 2 million tonnes to be saved annually in the near future.

We have also put in place systems to predict and monitor improvements in environmental performance. In particular, our PAGODA facility is now widely used to generate performance indicators for flight efficiency, fuel burn and greenhouse gas emissions; to support members and organisations requiring accurate domestic and international emissions inventories; and to support operational and policy-setting organisations in the analysis of how aviation’s CO2 emissions could be incorporated in the EU’s Emissions Trading Scheme.

EUROCONTROL is therefore becoming an increasingly key actor in the push to control aviation’s environmental impact. It has the systems, expertise and operational capabilities to support the air transport industry’s efforts to meet society’s demand for mobility, with the competing demand to reduce the environmental impact that the demand will itself generate.

*EUROCONTROL, the European Organisation for the Safety of Air Navigation, was created in 1963. See www.eurocontrol.int

©OECD Observer No 267 May-June 2008