Single European Sky

There were 9.6 million flights to or from EU28+EFTA airports during 2017, and they are forecasted to increase by 42% between 2017 and 2040 under the base traffic forecast. The Single European Sky (SES) initiative [51] has introduced regulatory instruments at the EU level to help address the environmental challenges associated with this expected growth.

Performance Scheme

The SES ‘Performance Scheme’ [52], [53] defines key performance indicators and sets mandatory local and EU targets in the fields of environment, safety, efficiency and capacity, while taking into account their interdependencies. The scheme captures the relationship between flight routing and environmental impacts through two Key Performance Indicators (KPIs). These involve measuring horizontal flight efficiency by comparing the great circle (shortest) distance against (1) the trajectory in the last filed flight plan (KEP) and (2) the actual trajectory flown (KEA). These KPIs are regarded as reasonable proxy measures of Air Navigation Service Provider efficiency.

Considering the complexity of the route structure, interface procedures and air traffic control operations, horizontal en route flight efficiency is not considered an appropriate performance indicator for the airport and terminal manoeuvring area. Instead, the additional taxi-out time and the additional transit time in the Arrival Sequencing and Metering Area (ASMA)11 is monitored against an unimpeded time based on periods of low traffic demand. Likewise, in order to measure the performance of aircraft ground operations at airports, the actual taxi-out time of a flight is compared to an unimpeded taxi-out time during periods of low traffic demand. At present, the performance scheme does not cover non-CO2 emissions, vertical flight efficiency, noise levels or air quality.

The European Commission is currently conducting a review of the Performance and Air Traffic Management (ATM) Charging Schemes which is due to be completed by the start of 2020. This will in particular respond to the findings of the recent European Court of Auditors report [54], and better capture the responsiveness of the ATM System to requests for preferred flight trajectories of airspace users.


11 ASMA is measured as a cylinder of airspace centred on the airport with a radius of 40 nautical miles.

Network Manager

The European Commission nominated EUROCONTROL as Network Manager in July 2011 until the end of 2019 [55], [56]. The SES Network Manager coordinates between operational stakeholders to effectively manage imbalances between capacity and demand, and thereby optimise the performance of the European aviation network. The aim is to prevent congestion in the air through the design, planning and management of the European ATM network and to limit unnecessary fuel burn and emissions through flow and capacity management.

Single European Sky ATM Research (SESAR)

SESAR is the technological pillar of the Single European Sky [57] funded by the European Union, EUROCONTROL and industry partners, with a total budget of €2.1 billion for the original SESAR programme (2008-2016) and €1.6 billion for the SESAR 2020 programme (2014-2024). It aims to improve ATM performance by modernising and harmonising systems through the definition, development, validation and deployment of innovative technological and operational solutions. These solutions are defined in the European ATM Master Plan, along with required operational changes and a roadmap for their implementation. The solutions are developed and validated by the SESAR Joint Undertaking (SJU), and deployed through ‘Common Projects’ supported by dedicated SESAR deployment governance and incentive mechanisms. All of these processes actively involve the stakeholders and the Commission in different forms of partnerships.

The implementation of the deployment framework [58] will allow SESAR to fully deliver its environmental benefits from concept to implementation. The European Union has contributed €1.5 billion from the Connecting Europe Facility Programme to support operational stakeholders in this process.