Sustainable airline planning and scheduling

With sustainability becoming one of the core topics in politics, public discussion and, consequently, in various industries, the airline industry, as one of the major greenhouse gas emitters in the transport sector, has also come under scrutiny. Despite many advanced models for airline planning and scheduling, most models do not explicitly consider sustainability issues. Our paper extends existing research by including the five most strategic stages of the airline planning and scheduling process along with explicitly emphasizing sustainability considerations. We use the resulting mixed-integer quadratically constrained problem in a computational study to show that airlines in our setting can reduce the number of flights (and thereby the level of emissions) without the need to make a substantial sacrifice in profitability. Due to the complexity of the problem, the results also indicate the need for a solver specialized in efficiently solving mixed-integer convex problems.