Air Transport Research for Tomorrow’s Mobility at EWGT 2025

The DLR Institute of Air Transport contributed nine studies spanning operational airline challenges, new technologies, and economic as well as regulatory analyses.

Digital Airline Twin – Intelligent Solutions for Airline Planning

The Digital Airline Twin is one of the institute’s core research areas. It enables the study of how complex planning and decision-making processes interact within airlines. At EWGT 2025, the team presented two contributions on specific challenges in data processing and the integration of maintenance procedures:

• Automated correction of incomplete or faulty input data¹: Newly developed algorithms combine different models to adjust and supplement flight schedules so that fleet assignments can be generated periodically. These corrections are also relevant for subsequent processes such as crew scheduling.
• Integration of flexible maintenance options into rotation planning²: The model presented directly incorporates maintenance accessibility into aircraft rotations, thereby improving planning robustness and operational safety.

With these approaches, scenarios such as the introduction of new aircraft types or alternative propulsion systems can be simulated, allowing their effects on operations and costs to be assessed.

Ground Times and Future Aircraft Concepts

Another study demonstrates a direct link between ground times and aircraft design, as well as between ground times and network planning³. Ground times determine requirements for the design of future hydrogen or electric aircraft – particularly tank configuration and insulation strategies. In addition, the study examined how ground times influence network robustness, utilisation, and passenger numbers.

Environmental Policy and Regulation – Non-CO₂ Effects in the EU ETS

One paper analysed the impact of integrating non-CO₂ effects into the EU Emissions Trading System (EU ETS) on operational and technical measures for reducing aviation’s climate impact⁴. The results show that considering non-CO₂ effects facilitates the implementation of climate measures, as it reflects economic costs more realistically and creates incentives for airlines. At the same time, intelligent policy design remains crucial to cushion cost increases and avoid competitive disadvantages.

A complementary study investigated the possible consequences of pricing non-CO₂ effects (e.g. contrails) within the EU ETS⁵. Different regulatory approaches were considered – from full coverage of all flights to departure-based models – and their effects on ticket prices, demand, and airline networks. The findings highlight variations depending on route networks and fare structures, providing insights into how climate measures in aviation can be designed to balance ecological goals with market stability.

Cost Pass-Through in the Airline Industry

Further empirical results show that airlines pass on around three quarters of rising costs – for example from taxes, charges, or fees – to passengers⁶. While industry-wide cost increases tend to have a more uniform effect, local charges often trigger diversion effects and distort competition between airports.

Airport Transformation: Infrastructure Investment for Climate Compatibility

Decarbonising air transport requires significant investment in green infrastructure, such as hydrogen refuelling facilities or renewable energy supply. The methodology presented provides a simulation-based financial model that evaluates both economic viability and environmental impacts⁷. This approach can help airports assess future scenarios and make well-founded investment decisions.

IAM Potential Analysis for the Hamburg Metropolitan Region

A study on Innovative Air Mobility (IAM) examined how air taxis could be integrated as feeder services to airports, using Hamburg Airport as a case study⁸. The results show that IAM offers time advantages on longer access routes, but also places high demands on airspace and ground infrastructure near airports. Even minor IAM delays, which offset time savings, can significantly reduce demand – a key factor for future IAM service planning.

Method Transfer: The Economic Role of Ports in Shipping

Applying its expertise in economic modelling to shipping, the institute analysed the economic role of sea and inland ports⁹. The study quantified direct and indirect employment effects and value creation using an input-output model and provided projections up to 2040, taking into account decarbonisation and shifting trade flows. Conducted within the FuturePorts project, the study demonstrates the transferability of economic modelling approaches to other transport sectors.

Research with Impact on the Future of Mobility

The DLR Institute of Air Transport’s participation in EWGT 2025 highlights the wide thematic range of its research. Methods such as the Digital Airline Twin offer insights into the interaction of complex airline planning and decision-making processes, including the evaluation of new technologies. Climate policy analyses provide a solid basis for policymakers and industry. Researchers also address infrastructure challenges and new mobility concepts – key issues for the future of airports and airlines. Together, these efforts lay the groundwork for an efficient, climate-compatible, and resilient air transport system.

1 _{Röhrs, M. et al. “Automated repair of input data for fleet assignment in a digital airline twin”, Proceedings of the 27th Euro Working Group on Transportation Annual Meeting (EWGT 2025), Edinburgh, UK.}

2 _{Albrecht, S. et al. “Flexible maintenance in aircraft rotation models: a modular component of the digital airline twin”, Proceedings of the 27th Euro Working Group on Transportation Annual Meeting (EWGT 2025), Edinburgh, UK.}

3 _{Stoebke, E. et al. “From ground to sky: Exploring the dynamics of ground times in relation to future aircraft design and airline networks”, Proceedings of the 27th Euro Working Group on Transportation Annual Meeting (EWGT 2025), Edinburgh, UK.}

4 _{Zengerling, Z. L. et al. “Integrating aviation’s non-CO2 effects into EU ETS: Impact of CO2e accounting on operational and technological climate mitigation measures”, Proceedings of the 27th Euro Working Group on Transportation Annual Meeting (EWGT 2025), Edinburgh, UK.}

5 _{Kölker, K. et al. “Net(-work) Impact of Non-CO2 Pricing in EU ETS: Demand and Ticket Price Dynamics in Air Transport Across Geographical Scopes”, Proceedings of the 27th Euro Working Group on Transportation Annual Meeting (EWGT 2025), Edinburgh, UK.}

6 _{Wozny, F. “Pass-Through of Firm-Specific and Sector-Wide Cost Changes in the Airline Industry”, Proceedings of the 27th Euro Working Group on Transportation Annual Meeting (EWGT 2025), Edinburgh, UK.}

7 _{Timmer, M. et al. “Sustainable airport development: a financial modelling and simulation approach for scenario-based decision making”, Proceedings of the 27th Euro Working Group on Transportation Annual Meeting (EWGT 2025), Edinburgh, UK.}

8 _{Pertz, J. et al. “From Gridlock to Airflow? Understanding the Total Travel Time for Advanced Air Mobility Demand at the Hamburg Airport”, Proceedings of the 27th Euro Working Group on Transportation Annual Meeting (EWGT 2025), Edinburgh, UK.}