Approaches to Charges Modulation for Operational Efficiency and Sustainable Aviation

In 2024, as part of the Single Sky Reforms (SES 2+), a mandatory modulation of enroute charges was proposed, with the aim to “incentivise the improvement of environmental performance by airspace users.” In this paper we focus on how charges modulation could be deployed to deliver airline flight efficiency, saving fuel, operational costs and reducing emissions by up to 3 % on some routes. Given that the Single Sky Reforms may mandate EU Member States to implement charges modulation, this paper advances ideas on the benefits and practicalities: where it could be implemented to benefit flight efficiency; how charges modulation could be implemented; and how the forthcoming regulations could be shaped to avoid unintended consequences or cosmetic implementation. We support our arguments with simulations of flight trajectories routed with discrete charges modulations in place. This is accomplished with our novel airspace optimisation tool, 'AirOpt'. AirOpt was developed to support national airspace designers and managers in their optimisation of airspace for civil and military use, including highly-modular variable profile areas (VPAs). The paper provides examples of where charges modulation could be beneficial: the North-East corner of the Scottish FIR; and the 'West-End' of the London FIR, which is proximate to the Irish Flight Information Region (FIR). We conclude that charges modulation may present an opportunity in certain key areas and could be deployed quickly to reduce emissions. It also has the potential to be a precision instrument in minimising flight inefficiency compared to broad approaches such as the application of a 'common unit rate'.