Time to Replace? A Guide for Sustainable Engine Maintenance Strategies

Aircraft engine maintenance planning is traditionally focusing on questions of economic optimization. This includes repair-versus-replacement decisions and the cost-effective scheduling of maintenance events and relies on operational data, shop visit forecasts, and contractual obligations. Although this approach has been subject of extensive study, the integration of environmental considerations into maintenance planning remains largely overlooked. For example, replacing Life Limited Parts (LLPs) in shorter intervals can improve engine efficiency and reduce fuel consumption, but increases material demand and lead to a higher number of shop visits, causing additional environmental impacts. Postponing replacement conserves resources but may lead to higher operational inefficiencies and greater fuel consumption. Therefore, the objective of this study is to examine the environmental consequences associated with the timing and frequency of LLP replacements. Furthermore, it analyses the impact of different replacement intervals on climate change, material resource consumption and engine performance. A comparative Life Cycle Assessment (LCA) study is conducted to quantify the environmental impacts of replacing LLPs at shorter intervals versus an optimized replacement interval. By varying the LLP usage, this study demonstrates how longer utilization influences the overall environmental impacts. These repercussions are compared to increased fuel consumption due to engine degradation by using a simplified engine performance degradation approach. The findings of the study indicate the significance of varying impacts of different replacement intervals on the overall environmental performance. Furthermore, the study underscores the importance of recycling strategies for improving resource efficiency and sustainability in engine maintenance.