Efficient modeling of aircraft emission inventories for technology impact assessment in future markets

Kurzfassung

In the context of global climate change and ambitious policy initiatives such as the European Green Deal, the aviation sector is under increasing pressure to develop aircraft with significantly reduced climate impact. To support this transition, it is essential to accurately simulate the potential climate impact of next generation aircraft concepts. A detailed 3D emission inventory, capturing emissions by latitude, longitude, and altitude, is crucial for this purpose, as it allows for precise modeling of how emissions at different altitudes affect atmospheric chemistry and climate processes—such as contrail formation and ozone changes—enabling more effective policy decisions and mitigation strategies. This research presents a comprehensive simulation tool designed to evaluate the emission impacts of next generation aircraft. The tool takes a holistic approach, considering not only changes in emissions, but also variations in flight altitude and the evolving dynamics of passenger demand within different world regions. By integrating technological, operational and market development aspects, the tool enables scenario-based assessments of future aviation pathways and supports informed decision-making towards more sustainable aviation. The tool's calculations are based on several input parameters, primarily pre-calculated three-dimensional global aviation emission inventory for the year 2023 serving as reference emissions. This inventory includes flight distances (required for contrail modeling) and emissions of key species, such as CO₂, NOx and H₂O, as well as additional details regarding the flight phases (climb, cruise and descent) and the aircraft generation responsible for the emissions (distinguishing between old and current aircraft). Emission inventories are stored separately for three market segments (regional, single-aisle and twin-aisle aircraft) and across multiple combinations of detailed world regions. The corresponding distance distributions for each world-region combination are also given. For each market segment and aircraft generation, representative design trajectories are defined. Future air traffic emission inventories computed based on heterogeneous growth scenarios for the Revenue Passenger Kilometres (RPK). These regional annual passenger growth rates are pre-defined according to various established forecasts, such as those provided by DLR and ICAO. A specific forecast scenario may be selected or adjusted as necessary to accommodate analytical requirements. For each of the three market segments, users can introduce next-generation aircraft types by incorporating fuel consumption and emission characteristics from design trajectories. The reference emissions are then scaled and adjusted for altitude, for each region, based on the relative changes between old, current and next-generation aircraft. If the user supplies data for different design missions, emission scaling and shifting is performed according to the region-specific mission distance distribution. This study showcases the capabilities of the tool and forecasts the impact of various next-generation aircraft types and heterogeneous RPK growth rates on emissions quantity and distribution. The next-generation aircraft design trajectories used in the study are sourced from the Digital Hangar of DLR, a comprehensive repository of next-generation aircraft models with varying ranges and capacities, including those driven by fossil kerosene, sustainable aviation fuel (SAF) and hydrogen. The effectiveness of the tool is demonstrated by these study results, which enable it to contribute to the development of next-generation aircraft that have a lower climate impact.