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Air Traffic Management for environment

Periodic Reporting for period 4 - ATM4E (Air Traffic Management for environment)

Reporting period: 2017-11-01 to 2018-04-30

One challenge for society is to develop sustainable aviation and reducing the anthropogenic contribution to climate change and enhancing environmental quality, e.g. air quality, is part of an answer to this challenge. Beyond the desire to minimise fuel use and by that CO2 emissions, currently the consideration of other environmental aspects in en-route flight planning has not been operational practice. Previous studies have shown that climate and environmental impacts can be reduced by operational measures, i.e. by changing flight trajectories. However, systematic and simultaneous consideration and optimization of environmental impacts, comprising climate impact, air quality and noise issues, are currently lacking. The exploratory research project ATM4E (Air Traffic Management for Environment, SESAR2020) addressed this gap and has explored the feasibility of a concept for a multi-dimensional environmental assessment of ATM operations working towards environmental optimization of air traffic operations in the European airspace.

The first objective was to establish a multi-dimensional environmental change function (ECF) concept, which includes air quality impact (LAQ for key pollutants) and perceived noise in addition to climate impact. This constitutes a new metric for an environmental assessment (Workpackage 1). The second objective was to plan flight trajectories which mitigate the environmental impact taking the actual weather situation and ATM constraints into account. ; and in addition to investigate to what extent the resulting “green” (low environmental impact air) traffic flows may lead to particular challenges for air traffic management (Workpackage 2). The third objective was to evaluate environmentally-optimized routes in a comprehensive climate-chemistry modelling allowing a proof of concept of climate-optimization with daily route analysis (Workpackage 3). Fourth and final objective was to prepare a Roadmap on implementation of climate-optimized trajectory planning in air traffic management.

ATM4E has demonstrated that the concept of ECFs (advanced MET service) has the strong potential to enable environmental assessment of aircraft trajectories and to identify climate-optimized routes. The results show many aircraft trajectories where reductions in the climate impact of about 10 or 20% can be achieved at the expense of additional fuel burn in the order of less than a few percent for the majority of flights due to avoidance of environmental sensitive regions. Hence, the case studies indicated a substantial mitigation potential for European air traffic that can already be gained by focusing on a limited number of “critical” flights only.
A multi-dimensional environmental change function (ECF) concept, for planning environmental optimized trajectories has been developed and applied in a one-day case study for Europe. Successful work has been performed to develop so-called algorithm-based ECFs which can be calculated efficiently using routinely available meteorological data.

For the planning of optimized flight trajectories air traffic data for Europe were selected and processed. The environmental impact of the selected air traffic including associated emissions has been determined with a trajectory calculator and simulating engine emissions. Environmental impact had included forming of contrails caused by these flights. Data preparations and advancements of the Trajectory Optimization Module (TOM) have been successfully finalized. A multi-phase concept for the integration of climate, LAQ and noise has been designed and implemented, considering three consecutive flight phases (take-off, cruise, and landing).The environmental optimization of aircraft trajectories has been conducted and the entire traffic of a characteristic winter day has been environmentally optimized in four dimensions with different ATM and optimization strategies. Based on the complete environmental-optimized European air traffic of that day, the implications to the ATM network have been investigated. For two typical traffic scenarios, demand-capacity hotspots were identified revealing that the European ATM network might have to deal with a shift of ATM sector load from one set of sectors to another with a tendency of relocation to lower altitude sectors in certain situations.

Within the project algorithm based Climate Change Functions (aCCFs) were established and verified. Environmentally-optimized routes were evaluated in a future atmosphere in a comprehensive climate-chemistry model allowing a proof of concept of climate-optimization with daily route analysis by using aCCFs. As an initial step towards full climate impact optimisation, a one-year simulation for contrail avoidance has been successfully completed and the consequent impacts on flight characteristics have been well understood. Secondly, the aCCFs have been successfully implemented in the global chemistry-climate model EMAC as a separate submodel which enables aircraft trajectory optimisation in an Earth system model for identifying climate-optimal trajectories.

Furthermore, three trajectory calculation cases have been designed with respect to the great circle, the cost optimal and the climate optimal flight planning option. Accordingly, the atmospheric changes arising from flights with minimal cost or minimal climate impact were identified in comparison to the baseline great circle flights, including changes in ozone, methane, and water vapour.
In order to have available at the end of the Project a roadmap with recommendations and an implementation strategy for the environmental optimization of aircraft trajectories, close collaboration and communication with aviation stakeholders have been established. The multi-dimensional assessment concept has been published in a peer reviewed paper. For environmental optimisation an overall implementation has roadmap been prepared in cooperation with aviation stakeholders, which has been presented at several thematic stakeholder workshops and to the wider scientific community during scientific conferences.
The derivation of algorithmic Climate Change Functions, with their dependence on prevailing weather conditions, is novel. For the first time, the entire traffic of a characteristic winter day (18 December 2015) has been environmentally optimized in four dimensions with different ATM and optimization strategies. It is the first time that algorithmic Climate Change Functions were used in such a wide-ranging optimization. The comprehensive trajectory data and the multitude of optimizations per route using different cost function weights allow for various interesting assessments and provide understanding of how environmental-optimized flying in Europe would look like and how it might be eventually accommodated. Moreover, the implications to the ATM network caused by environmental-optimized flight planning have never been investigated in such a comprehensive case study before.

Progress towards greening of aviation has been achieved by developing a multi-dimensional environmental assessment framework. Such a framework unifies individual environmental impacts of aviation and environmental performance criteria. Having available such an assessment framework enables a comprehensive, simultaneous analysis and optimization of environmental performance of aircraft operations and trajectories.