Air traffic management - Sustainable policy

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Europe is working towards an efficient, unified aviation policy. But that may not be enough.

David Learmount/LONDON

Air transport systems in many parts of the world are soon going to be overstretched, and Europe's will be the first to hit the limits.

In respects such as air traffic management (ATM) capacity, Europe has reached its limits several times already. The questions that remain are how far today's limits can be extended, and when will they reach the point where pushing them further becomes technically impossible or environmentally unacceptable.

Europe's air transport system could reasonably be compared with the USA's in terms of development and maturity, but its ATM system remains nationally fragmented while the USA's is federal. Yet Europe - not including European Russia, the Ukraine and Belarus - has less than half the geographical area of the USA and nearly twice the population.

China's population density of 127 people/ km2 is significantly greater that Europe's and 4.5 times that of the USA, so it could also be expected to have an overstressed air transport system. It does, but in a different way because its economy has considerable development ahead of it before the country can provide a comprehensive and mature transport infrastructure. In China, the question for travel system planners is whether business activity and the people's disposable income - and, therefore, demand for travel - will grow faster than the country can develop its transportation.

Europe and the USA, on the other hand, both have mature transport systems, so their capacity for development is more limited. Also, Europe has a population density of 110 people/km² while the USA has only 28 people/km². These factors have implications not only for the transport capacity required, but for the perceived effect that the transport system - particularly airports - has on the environment.

When the UK Government issued a consultation paper in February, The future of aviation, it was looking for comment to enable it to formulate air transport policy for the next 30 years. Seeing that far into the future is difficult, especially when the overloaded infrastructure is inevitably going to impose limitations as it has never done before. Earlier government consultation papers and studies have simply concerned themselves with how to provide the infrastructure to cope with growth in demand. Now, for the first time, the paper includes questions not only about whether demand can be met, but whether it should be met. Future prospects are likely to be similar for capacity-strapped areas of Europe such as Frankfurt, Paris and Amsterdam. The only likely variation is how soon the local infrastructure will reach its limits.

The European Civil Aviation Conference (ECAC) predicts that market demand will lead to a 60% growth in annual air transport movements by 2015, meaning that the annual number of flights in European skies will increase from 8.5 million to 13 million. No organisation is claiming that existing plans for improving airspace capacity will increase it by more than 30%. The European Commission (EC) transport commissioner Loyola de Palacio makes it clear: "We have to be aware that the reorganisation of air traffic control (ATC) will not end congestion and eliminate all problems concerning air traffic organisation. The next challenge for Europe will be the progressive optimisation of the overall transport system."

Growth will have to take place in under used airspace to meet the growing demand for air travel. This is why planners stress that point-to-point traffic growth is important, rather than increases on trunk routes between major hubs.

ATM planning

Apart from demand, airline business expansion rates are determined by airport and airspace capacity. These can be limited by environmental regulation as well as factors like runway and passenger handling capacity. With the exception of 1991, the year of the Gulf War, demand has never failed to grow, and in Europe over the last five years or so passenger traffic has risen by 5-8% a year.

Airport and ATM development in Europe is government controlled - or at least limited - because governments control the finance for ATM in most European states. Final permission for airport development, construction, changes in airspace structure or policy have to be approved at national government or European Union Council of Ministers level. Even in the UK, where the newly part-privatised National Air Traffic Services (NATS) is to be commercially financed, the Civil Aviation Authority (CAA) remains the ultimate arbiter of how airspace may be restructured and used. So even with "privatised" air traffic services (ATS), the UK model keeps airspace policy in the public domain. The slogan of the many anti-privatisation UK politicians - "our air is not for sale" - was never the issue. Only the management of air traffic has been "sold".

De Palacio has had great success in getting the Council of Ministers to agree, in principle at least, that the ultimate goal for European ATM is the "Single European Sky". Before the EC took up the challenge, Eurocontrol had for years set itself the same goal, which it used to call "One sky". In Eurocontrol's schematic diagram for the programme of ATM changes and upgrades leading to that objective, the date axis becomes dotted after 2015, with the date for "One sky" tellingly marked as "One day".

Turning the Single European Sky into a reality is not as easy as political "agreement in principle" makes it look, because in many cases states will either have to modify their constitutions or their interpretation of them. However, the Eurocontrol plan - accepted by the political body ECAC - labels 2010-2015 as the period during which "fully flexible use of airspace not constrained by national boundaries" should be achieved. After that, the only remaining objective is full transfer of responsibility for European ATM to a single, centralised European agency. John Arscott, the UK CAA's director of airspace policy, explains that there is definitely a philosophy among states which accepts the single sky, adding: "To what extent the politicians react depends upon their perception of what people want."

Airspace policy and structure needs to be harmonised in all ECAC/Eurocontrol countries, and the "ATM 2000+" strategy has been developed with that in mind. Airspace policy and structure is a matter for the states (not the ATS providers) to agree, but harmonisation would make life much easier and more efficient for ATS providers. The latter will take advantage of improving technology, like the Mode S datalink and Automatic Dependent Surveillance-Broadcast (ADS-B), for communications and enhanced surveillance. Enhanced Mode S datalink will enable the trajectory selected on an aircraft's flight management system (FMS) to be monitored. ATM computers will be able to compare trajectories in four dimensions (the fourth dimension being time) and predict potential conflicts some distance ahead. It is on the basis of this kind of capability that progress toward "free flight", or autonomous operation, will be able to take place.

At some stage en route to the Single European Sky, ATS provision will need to become separated from the state. The process may take place country by country to begin with, but since the ultimate goal of a single sky implies that national boundaries will not play any part in ATM and a centralised agency will manage traffic, governments are going to have to relinquish ATM in due course.

Meanwhile airspace can be made much more efficient by reducing the number of airspace classifications. At present, blocks of airspace are classified alphabetically into seven categories from Class A to Class G. Grading depends on who may use the airspace, under what conditions, and carrying what kind of equipment (transponder/datalinking capability, anti-collision systems etc). Eurocontrol proposes that the seven classifications be reduced to three by 2010:

Class U: not all traffic in this airspace is known to ATC (air traffic control); Class K: all traffic is known to ATC in terms of its position and/or intentions; Class N: the position and intentions of all traffic is known to ATC.

These would be further reduced, to two, by 2015, Class K airspace becoming Class N. The most important overall change that would come with harmonisation of national airspace policies is that Class N airspace would cover all airspace above an agreed level, and that level would be the same in all ECAC states. It would be up to states to decide in which lower airspace areas - like terminal areas around major airports - Class N airspace would extend below the common level. The remaining airspace would be class U.

Airport planning

The UK Government's consultation paper poses a key question about the air transport industry's development, which all Europe's states and central bodies like the ECAC must face: "Should we choose policies that respond to the demands of consumers and allow current growth patterns to continue...or are the costs of this approach too high, and should we therefore choose policies to limit environmental impacts and ration a limited supply by pricing or otherwise?"

The Airports Council International, Europe (ACI Europe) hedges its bets, proposing: "The future growth of aviation in Europe at projected rates of up to 6% should be seen as an opportunity to bring further economic and social benefits from air transport while balancing the environmental effects of aviation activity."

Predictably, any moves by airlines to operate quieter aircraft are welcomed by the ACI. So are moves by regulators to define and accelerate progress toward ICAO Chapter 4 noise standards, on the basis that the quieter aircraft movements become, the less local opposition there will be to traffic growth. The Association of European Airlines (AEA) also favours acceleration toward Chapter 4 standards because it fully acknowledges the importance of environmental issues in this crowded continent. It is less strident, however, on the phase-out of Chapter 3 aircraft than ACI Europe because its own members foot the bill for re-equipping.

ACI Europe and AEA both favour pan-European rather than local noise regulation. In practice, it is difficult to see pan-European noise standards completely excluding specific local requirements.

Land-use planning in the vicinity of airports is cited by ACI Europe as important for the future. The argument is that those airports which are not already hemmed in by buildings - especially residential property - should either protect themselves from future noise complaint by buying land under flight paths, or governments should ban residential development there on safety and environmental grounds. It is too late in the case of most major airports, but if, as proposed by the ECAC, provincial airports are to play an important part in providing additional air transport capacity in the future, legislation may not be too late to prevent housing developments springing up under their flight paths. Such action, however, requires political time and volition.

Environmental concerns

What is certain is that it is becoming increasingly difficult for governments to build airports on greenfield sites. Even where this can be achieved, there will be argument over damage to wildlife, and aviation's growing contribution to global warming as a burner of fossil fuels.

Transport Commissioner de Palacio, referring to the rapid commercialisation and liberalisation of the formerly government or local authority-controlled airport sector, says that because of the importance to the economy and to society of air transport, "the time has come to open a dialogue on the elements of a European airport policy. We need to give some thought to the regulatory framework and financing instruments the airport industry may require."

Slot allocation at airports is the method of distributing runway time to airlines to run their schedules. This system only becomes necessary when an airport is busy either all the time or during peak periods. The EC, the AEA and ACI fundamentally disagree on how these should be allocated. The AEA says that airlines who have slots should keep them, but on a use-it-or-lose-it basis. They should also have the right to swap or trade them. De Palacio says: "I feel the time has come to make it clear in legislation that there are no property rights associated with slots. Slots are public goods, and the airlines using them are beneficiaries of a concession". De Palacio says she intends to reopen the debate on slot allocation systems, attempting to take a global look at the issue.

Centralising the formulation and execution of safety regulation for the whole of Europe, in the same way that the Federal Aviation Administration carries out that function for the USA, is not plain sailing even for European Union member states which are also members of the Joint Aviation Authorities (JAA). But the EU Council of Ministers has agreed that a European Aviation Safety Agency (EASA) should eventually unify European aviation safety regulation, and de Palacio backs this policy, not least because it ensures a regulatory level playing field for manufacturers and operators. De Palacio emphasises that an EASA also would be responsible for airport safety, an area which has not so far been covered by Joint Aviation Requirements (JARs).

The problem is that the JAA is an effective forum for agreeing common policy, but has no executive power. It is up to individual states to make JARs into national law and while some are quick to do so, others are slack. Strangely, non-EU countries which choose to adopt JARs are more likely to be assiduous in implementing them because the process is voluntary.

The method, as proposed at this stage, for creating an EASA which has pan-EU lawmaking ability is for it to be an autonomous EC unit which, effectively, makes JARs into law. Safety oversight will be devolved to national aviation authorities. The AEA is so keen to have safety regulation unified - simplifying licensing, certification and operations rules for all the airlines - that it says: "If the current Community framework cannot accommodate the required structure, then Council and Parliament should seek political initiatives to make the vision possible."

Where there's a will

There is no lack of coherent vision in the various industry bodies, national governments and European agencies. They know where they want to go, and all roads lead in the direction of unified standards. The destination can be seen shining clearly on the far horizon, but if demand keeps rising faster than the infrastructure can sustain, the shimmering destination may turn out to be a mirage.


The issue

Airline (AEA) view

Airport (ACI Eur) view

EC view

Airport capacity

Meet customer demand

Increase "environmentally sustainable" capacity

Better use of present airports, more point to point, plus integrated transport policy


Improve regulation of the system

Increase the role of the airports in allocation

Slots are publicly owned. Allocation should favour new entrants

Air traffic services

Favours single European Sky and independent ATS

Favours single European Sky

Favours single European Sky

Aircraft noise

Co-operate with regulators

Wants Chapter 4 as soon as possible

Hopes industry will adopt Chapter 4 ahead of deadlines


Co-operate with regulators

Phase out all marginal Chapter 3 aircraft

Negotiating at ICAO for no more hushkits


In favour of a truly autonomous EASA

In favour

In favour


End international "regulatory fragmentation"

In favour

In favour

Environmental charging


Opposed unless other transport modes are charged

Aviation fuel should be taxed

Notes: AEA (Association of European Airlines, ACI Eur (Airports Council International, Europe), EC (European Commission)