Aviation presents unique challenges for conventional Life Cycle Assessments (LCAs) due to its system complexity, long service lifetimes of aircraft, and highly globalised operations. While methodological approaches exist to account for temporal and spatial variations in Life Cycle Inventories (LCIs), they have been applied to limited extent or low spatio-temporal resolution. In this study, we demonstrate how spatio-temporally resolved datasets and life cycle simulation can be systematically integrated into LCAs for aircraft. For this purpose, we combine discrete-event modelling with the LCA framework, dividing the complex aircraft life cycle into individual events, such as single flights or maintenance activities. Each event is characterised by time and location attributes. In this study, maintenance activities are used as a representative use case to demonstrate the approach by allowing dynamic adaptation based on temporal and spatial factors. Our results show, that the implementation of dynamic LCIs in a discrete-event life cycle simulation framework has the potential to increase the accuracy of environmental assessments of aircraft and other complex technical systems. Such dynamic modelling could be particularly relevant for the application of novel technologies, as their benefits may vary substantially over time and space.

Hydrogen (H2) fuels are seen as alternative propulsion fuels to reduce aviation’s contribution to climate change as it does not produce carbon dioxide upon combustion. One major challenge for this transition is that hydrogen production routes often entail emissions that drastically reduce the environmental benefits of adopting the technology. Low-impact H2 production is associated with three processes; electrolysis powered by renewable energy, biological fermentation and biomass gasification. Impacts of the latter two can potentially be further reduced by carbon capture and storage. Several datasets to support life cycle assessments (LCAs) of mentioned H2 production routes exist, but are limited by different temporal and geographical scopes. Future changes in energy systems as well as technology developments will have a major effect on the long-term impacts of hydrogen production. Not considering these changes will distort decision-making based on prospective assessments. This study addresses this gap by harmonizing existing data for the three most prominent water electrolysis technologies and developing prospective H2 production life cycle inventory datasets for Europe. Only the production of hydrogen itself is considered, excluding liquefaction, storage and distribution to the aircraft refueling point. We consider the technological changes that are partially expected to lead to dramatic reductions in material intensities of the electrolysers. By harmonizing regionally specific background data, this work contributes to a clearer understanding of the conditions under which green H2 fuels can deliver substantial climate benefits as future aviation fuels.

With initiatives such as the European Green Deal establishing more stringent environmental requirements, there is an increasing need to develop aircraft technologies and sustainable aviation practices with reduced climate impacts. Additionally, conventional environmental Life Cycle Assessments (LCAs) often struggle to capture the dynamic and complex nature of aircraft operations; in particular, non-CO₂ in-flight impacts, which contribute significantly to climate change, are often overlooked. In this study, we improve a discrete-event LCA approach with a climate impact evaluation model and apply it to scenario analyses comparing different aircraft designs, fuel types, and flight schedules. Our findings reveal that, contrary to previous LCA studies, the climate impact per kilometre flown increases with longer flight distances and that an efficiently planned flight schedule can reduce the overall environmental impact. The study highlights the necessity of incorporating non-CO₂ effects and operational scenarios into LCA to achieve a more accurate understanding of aviation's environmental impact.

As the aviation industry strives to minimise its environmental footprint, understanding the full life cycle impacts, including maintenance, becomes essential for sustainable development. This paper addresses the critical research gap in the environmental assessment of aircraft maintenance by conducting a comprehensive life cycle assessment based on an Airbus A320 aircraft. By combining a top-down check-level analysis and a detailed examination of the aircraft manufacturer's maintenance planning document, this study provides significant insights into the environmental implications of maintenance activities. The check-level analysis provides a general overview, while the analysis of the maintenance planning document delves into individual tasks, enabling the identification of components with the highest ecological impacts. This research emphasises the importance of including aircraft maintenance activities in life cycle assessment studies and provides valuable guidance for researchers, industry practitioners, and policy makers in prioritising sustainability measures and enhancing the environmental performance of aircraft throughout their life cycle.