With 27 separate airspaces, Europe's skies are getting increasingly crowded and polluted, leading the EU to push for the realisation of a "Single European Sky". But member states' reluctance to hand over sovereignty in this area could be slowing down the process.


Airspace is one of the areas in which European integration has been slow to keep up the pace. Indeed, the European sky is still divided into 27 different pieces of airspace that remain under the control of national governments. 

This fragmentation has negative repercussions in terms of the efficiency of Europe's air travel because airlines have to cut across numerous air-traffic control systems in order to get to their destination. It also causes safety concerns by creating additional traffic jams in the air and adds to air pollution by forcing planes to fly extra kilometres and assume holding patterns when airborne before being able to land in Europe's busy airports. 

Airlines' activities are currently responsible for just 3% of the world's greenhouse gas emissions but this is expected to rise as air traffic doubles by 2020.

To address these issues, the Commission launched an initiative, in 1999, aimed at creating a 'Single European Sky' (SES) by reforming the current Air Traffic Management system. A series of regulations was adopted in March 2004 with a view to implementation by 2025. But, conceding that these regulations had "not delivered the expected results in some important areas," the Commission, in June 2008, put forward a second package of legislation. 

The Single Sky initiative is part of a three-pillar strategy aimed at greening aviation, which includes the establishment of a 'Clean Sky Joint Technology Initiative' and legislative proposals to include the sector in the EU's emissions trading scheme (see LinksDossier on Aviation & ETS). 

The Clean Sky initiative is a €1.6 billion public-private research partnership to help the air-transport industry develop environmentally friendly technology for planes. It was officially launched in February 2008 with the aim of halving noise, fuel consumption and CO2 emissions per passenger kilometre, as well as slashing nitrogen oxide (NOx) emissions by 80% by 2020. 


A growing sector with growing problems

Aviation appears to have recovered from the temporary slowdown following the 11 September 2001 terrorist attacks. The European Commission estimates that air traffic will grow by 4-5% annually over the coming years, leading to a near doubling of traffic by 2020. 

"Current air traffic control infrastructure will probably be incapable of meeting the new challenges relating to the sustainable development of European air transport," states a March 2007 Commission Communication reviewing the European aviation situation. According to the report, the capacity of the current air traffic management (ATM) system has "reached its limits," while the technologies used "are obsolete". It adds that "the proliferation of different technical systems remains a concern". 

The result has been a sharp increase in delays for aircraft, with major repercussions for both users and airlines, for whom hold-ups can cost up to €2 billion a year. The rise in traffic also adds to safety concerns and is causing emissions from the sector to grow despite technological progress. 

Ambitious targets

The creation of a Single European Sky (SES) is due to tackle these issues. Its stated objectives are to: 

  • Triple capacity; 
  • Halve operating costs, 
  • Reduce the environmental impact per flight by 10%, and; 
  • Increase safety by a factor of 10. 

Reorganising airspace:

The EU's upper airspace is currently defined by the national borders of its 27 members and managed by more than 50 air traffic control centres. The fragmentation impacts on safety, limits capacity and adds as much as €5 billion per year to operating costs, according to the Commission. It concludes that a more rational organisation of air traffic, with greater portions of airspace operated as one single entity, could thus help resolve the looming air capacity crunch faced by the EU.

A key tool proposed by the EU executive in this respect is the so-called 'functional airspace blocks' (FABs), whereby two or more countries can agree to integrate their upper airspace and designate a single service provider to control air traffic in that block. FABs are also be extended to non-EU countries.

To overcome governments' concerns about ceding control over their national airspace, current legislation allows for a "bottom-up" approach whereby it is left up to the member states to decide on how to restructure. Member states were to have the FABs in place by 4 December 2012.

However, European officials conceded that ambitious plans to consolidate national air traffic control into a regionalised system had failed, hampered by national inaction despite years of planning.


Siim Kallas, the European Commission vice president in charge of transport, vowed to take “every possible action” to enforce the eight-year-old agreement after many countries missed the 4 December deadline for merging national air traffic control space into nine functional air blocks.

A technological revolution


The SESAR project (formerly known as SESAME) is the technological component of the SES, aimed at modernising air traffic management systems and infrastructure so as to facilitate the re-organisation of European airspace. 

SESAR consisted first of a four-year "definition phase", launched in 2004, during which a consortium of 29 companies and organisations representing airspace users, airports, supply industry, safety regulators, controllers and research centres drew up an "Air Traffic Management Master Plan" outlining development and deployment plans up to 2025 for next-generation ATM systems. 

Following the formal presentation of the 'Master Plan' on 6 May 2008, a five year "development phase" was launched under the control of the 'SESAR Joint Undertaking' (JU), which involves 32 companies, including aircraft operators, Airbus and other stakeholders. Their role is to develop the new systems and infrastructure, of which large-scale construction should begin as of 2013, under the final "deployment phase". 

The technological advances envisaged include the use of satellite navigation for more accurate trajectories and a better knowledge of meteorological data with a view to improving the ability of traffic controllers and pilots to anticipate problems. A more efficient telecommunications network would also be established to replace anachronic radio control systems that increase the risk of mistakes and misunderstandings and result in flight safety problems. An updated telecommunications network would also give all stakeholders simultaneous access to flight information status, reducing arrival queues at airports and disembarkation delays and helping to improve responses to security crises.

New sensor technologies, increased automation and "smooth approach" procedures are also being developed to help improve visibility and reliability while reducing noise and gaseous emissions. 

Question marks over financial support

A total of €1.4 billion from the European Commission (€350 million under the Community's Seventh Framework Programme for Research and Development and €350 million under the trans-European transport networks budget) and Eurocontrol (€700 million) will be available for R&D work and cross-border projects developed during the second phase of SESAR. The rest of the money is to come from governments and industry, although whether this will happen in practice remains dubious.

The airport capacity crunch

Around 30 major airports in Europe, responsible for handling 70% of the continent's traffic, are considered capacity-constrained. And yet, despite the fact that a shortage of runway capacity would render major investments in airspace capacity pointless, the 'Master Plan' does not address the issue, because it is a local or national planning issue over which Brussels has no power. And governments are not always willing to find the necessary money and confer planning permission for airport expansions. 

So instead, the Commission has presented a separate action plan on tackling congestion at airports, which calls on governments to optimise existing capacity through improved slot allocation and more efficient flight plans. Parliament has however criticised the Communication for not going far enough, arguing that the EU will need new airports. In a non-binding report, it called on the EU executive to come up with a "Master Plan for enhanced airport capacity in Europe" before 2009, with measures to "promote and coordinate any national and cross-border initiatives for building new airport capacities". 

Safer skies

The new package also aims to transfer increased competences to the European Aviation Safety Agency (EASA). While the agency currently deals only with the certification and safety of airlines, Brussels wants to hand over responsibilities for aerodromes, air traffic management and air navigation services to the agency so as to counter the rising safety risks related to the increased operational pressure as traffic rises. 


European Transport Commissioner Antonio Tajani  urged EU governments to "overcome the idea that national sovereignty prevails over airspace", saying the current situation was "ridiculous", causing aircrafts to fly on average 49km more than is strictly necessary.

Jacqueline Tammenons Bakker, chairwoman of the 'High Level Group' on the EU's aviation regulatory framework and the Netherlands' Director General for Air Transport, said the continuing fragmentation of EU skies places an unnecessary financial burden of €3.3 billion per year on both airlines and passengers. The HLG's July 2007 report sets out ten recommendations to speed up implementation of a Single European Sky, including granting more regulatory powers to EU bodies such as Eurocontrol and the European Aviation Safety Agency (EASA) - as member states are to blame for the delay in implementation - new economic legislation to encourage individual air navigation service providers to work together in order to reduce costs and addressing the EU's airport-capacity crunch to avoid bottlenecks on the ground. 

French State Secretary for Transport Dominique Bussereau, whose country will hold the EU Presidency during the second half of 2008, said speeding up progress towards the SES would be a top transport priority. But earlier statements from the French Senate state that "national security must come first". 

According to the Association of European Airlines (AEA), around 12% of European airlines' carbon-dioxide output is needlessly caused by inadequate infrastructure. AEA Secretary General Ulrich Schulte-Strathaus said: "While the EU seeks to incorporate aviation into the Emissions Trading Scheme, we are facing the prospect of having to buy permits to fly round in circles waiting for landing slots, or zigzag across the sky from one national airway network to another." 

The association believes that the SES project "is technically feasible" and that "its greatest obstacle is political". 

European airports association ACI Europe President Yiannis Paraschis said: "The de-fragmentation of the European sky through SES is the key element that requires immediate action." But he highlighted the lack of attention paid to airport capacity in current SES legislation. "Airport capacity is the main bottleneck that the aviation system will be facing over the coming years. You can add as much capacity in the sky as you want, but if this is not matched by capacity on the ground, you are not resolving anything but rather just creating more inefficiency from an economic and environmental point of view […] Optimisation of existing capacity is not enough, what is needed is new airport infrastructure." 

Paolo Carmassi, President of Honeywell Aerospace’s European, Middle Eastern and African (EMEA) operations, whose company is involved in the SESAR project, says implementation must be much faster. "We are in favour of efficiency – it goes directly on our balance sheet. So if there's a way to reduce my fuel bill by 1%, then I am not going to wait for legislation to do it. But what we need from regulation is for it to help us build an air traffic management system for the third millennium. And waiting for the ultimate solution is not an option. We favour a much faster implementation of incremental changes as opposed to waiting for a large-scale change. The sooner we start introducing what’s available the better. For the moment the implementation date for a number of new procedures and technologies is 2020 or 2025 and we frankly think that’s to long,” he told EurActiv, pointing to potential costs of delays for the next decade of as much as $170 billion. 

European Federation for Transport and Environment (T&E) and Climate Action Network (CAN) Europe say that the system of air traffic management must be restructured "urgently" to take better account of environmental impacts. "Contrail formation and thereby cirrus cloud build-up can largely be avoided by making aircraft fly at altitudes and flight paths where meteorological circumstances are more favourable. Often minor changes are enough to avoid most of the impacts. Restructuring the system of air traffic management to better take into account these impacts is therefore urgently needed," they state. 

While Friends of the Earth Europe supports the objectives of the SES, it argues against increased airport capacity as an instrument for reducing air traffic bottlenecks, saying that the costs of airport expansion, which include increased air and noise pollution, damage to built and natural heritage and to local communities, and additional road congestion, outweigh the benefits. 


  • March 2004: Adoption of regulations aimed at creating a 'Single European Sky'.
  • 25 June 2008: Presentation by the Commission of a detailed assessment of progress on the Single European Sky and of fresh proposals for speeding up implementation.