آسمان واحد اروپا و بلوک های حریم هوایی کاربردی: آیا آنها کارایی اقتصادی را بهبود می بخشند؟

The paper examines the potential economic efficiency of on-going changes in the European air traffic control system. Air navigation services in Europe are undergoing a process of consolidation and technological changes known as the Single European Sky initiative. The ultimate aim is to shift the industry from a paradigm based on national borders, to one where operational efficiency is the goal. One of the key components of the movement toward this is the notion of functional airspace blocks (FABs) whereby blocks of airspace are combined as a precursory to total unification of the system. To study the effects that those changes might have on the economic efficiency of the system, a data envelopment analysis framework is used. Although these FABs are not yet deployed, it is possible to simulate, ceteris paribus, how these different systems would have ranked in terms of economic efficiency by using data for each individual air navigation service provider.

Air navigation services (ANS) involve a complex network that handles the movement of aircraft at and around airports and in their movement between those airports. Under the 1944 Chicago Convention, governments have sovereignty over their national air space, and thus each country has traditionally dealt with this issue by having its own air navigation service provider (ANSP) that handles ANS and other related matters such as weather information services and flight planning. This has continually posed challenges of ensuring both the internal efficiency of individual monopoly suppliers of ANS and the external efficiency of ensuring optimal coordination of service between a series of network suppliers. The economies of scale, scope, and density involved in ANS provision, together with the external economies associated with each unit being a supplier in an interactive network makes not only the provision of optimal services difficult, but also the measurement of exactly what efficiency entails. This contrasts somewhat with the other two main elements in the air transportation supply chain; airlines and airports. Airlines have been the subject of economic deregulation, beginning in the US, for some 35 years, albeit it at various rates and forms in different countries. In general this has enhanced the efficiency of airline operations (Barbot et al., 2008). Airports have also seen changes in many countries with moves to remove them from excessive political control, open up new sources of finance, and to tie airport fees more closely with the costs of airport use (Barbot, 2004). This has involved changes in institutional structures of the facilities, ranging from overall ownership and control, to outsourcing particular elements of service (Barbot, 2012). There have also been considerations to link the operations of airlines and airports to enhance efficiency and encourage long-term stability services (Barbot, 2011). There has been much less activity regarding the provision of ANS. What has been done has largely been to change the institutional structure under which services are provided, moving away, except in the notable case of the US, from provision by a government department to various forms of corporatized structure, and in the case of the UK, public-private company (Button and McDougall, 2006). Reforming air traffic control is, however, inherently more difficult than deregulation of airlines and airports. The infrastructure in long lived and highly integrated making piece-meal reforms difficult. There is the need for, if not complete standardization, at least the use of a common platform to allow aircraft to be passed smoothly and safely from one control area to another. In contrast, aircraft can vary considerably as can airports, and a wide variety of varying technologies infrastructure can be used in both a competitive and cooperative manner. Some of these factors lead to a questioning of whether ANS are being provided and used efficiently, and if there are issues, how could the system be improved. Aircraft, are mobile and if airlines are unhappy with the local infrastructure or are competitively unsuccessful in any market, they can rapidly be deployed elsewhere. While airports are certainly not mobile, there is considerable competition amongst them for business, with large airlines in particular exercising countervailing power (Button, 2010). ANSPs in contrast are institutional monopolies, and indeed given the scale effects involved also have significant features of natural monopolies. Here we supplement the work of Barbot and others on the efficient supply of airline and airport services, by considering the efficiency of ANSPs. The focus is on Europe, and in particular on the efforts to unify the ANS of the region. Other studies have pointed to the current levels of inefficiency that exist, and EUROCONTROL has for a number of years collected data and monitored the situation. Here we hone in on a particular aspect of the on-going efforts to improve the European situation, by assessing the role that greater local coordination of ANSPs may play in the longer-term policies of establishing a full Single European Sky (SES).

Although airspace is a common resource, air traffic management in Europe is still organized in a fragmented way. Every time a plane enters the airspace of a Member State, it is serviced by a different ANSP on the basis of different rules and operational requirements. Each provider procures tailored equipment and most maintain their own training schools and all other support functions. This fragmentation impacts on safety, limits capacity, and above all, adds to cost. The move to a Single European Skies, however, has, despite the potential benefits for Europe as a whole, proved problematic. The efforts to overcome this, or at least to improve the situation, have essentially been “regional” reforms of airspace with greater integration of similar, adjacent systems. The analysis here provides insights into the nature of the FABs, looking at their relative efficiencies over time and some factors that may explain differences. It provides, however, little more than background to a largely political process, but does highlight some of the quantitative considerations that need to be thought through.