scope:

Report Scope

Figure 1-1 shows the geographical scope of this report with the US CONUS subdivided into 20 Air Route Traffic Control Centers (ARTCCs) and the European area subdivided into 62 en-route centres².

Unless stated otherwise, for the purpose of this report, "Europe" is defined as the geographical area where the Air Navigation Services (ANS) are provided by the European Union Member States plus those States outside the EU that are members of EUROCONTROL3, excluding Oceanic areas, Georgia and the Canary Islands.

Unless otherwise indicated, "US" refers to ANS provided by the United States of America in the 48 contiguous States located on the North American continent south of the border with Canada plus the District of Columbia, but excluding Alaska, Hawaii and Oceanic areas (US CONUS).

In order to ensure the comparability of operational ATM performance, the analysis scope of this report was influenced by the need to identify a common set of data sources with a sufficient level of detail and coverage. Therefore - unless stated otherwise - the detailed analyses of ATMrelated operational performance by phase of flight in Chapter 5 are limited to flights to or from the main 34 airports for IFR traffic in both the US and in Europe. A detailed list of the airports included in this report can be found in Annex I.

Although they are within the top 34 airports in terms of traffic in Europe in 2015, Istanbul Ataturk (IST), Istanbul (SAW), Antalya (AYT), and Warsaw (WAW) airports were not included in the analysis due to data availability issues.

The 34 main airports used for more detailed performance tracking are also shown in Figure 1-1. Although these airports remain consistent for the most part, there have been minor changes since the last comparison report in 2013. In the US, Dallas Love (DAL) and Nashville (BNA) have replaced Cleveland (CLE) and Raleigh-Durham (RDU).

For the US, many of these high volume airports are located on the coasts or edges of the study region creating a greater percentage of longer haul flights in the US, especially when only flights within the study region are considered. The airborne trajectory on these transcontinental flights may be more affected by the influences of wind and convective weather.

TEMPORAL SCOPE

The operational analyses in this report were carried out for the calendar year 2015 and, where applicable, comparisons to previous years were made to track changes over time. In particular, this report contrasts the performance of 2015 versus the performance observed (and reported) in the 2013 edition of this report.

² The map shows European airspace at Flight Level 300. Therefore not all the en-route facilities are visible as some control lower airspace only.