Accommodating new flights into an existing airline flight schedule

TL;DR

This paper introduces two innovative methods for integrating new flights into existing airline schedules, optimizing profit by adjusting cruise speeds and aircraft swapping, supported by advanced mixed-integer conic quadratic formulations.

Contribution

It presents novel optimization approaches incorporating aircraft speed adjustments and swapping, with strong formulations enabling efficient solutions for large-scale airline scheduling problems.

Findings

Optimal solutions for 300-flight instances within reasonable time

Effective trade-offs between flying time and fuel burn

Enhanced flexibility in scheduling through aircraft swapping

Abstract

We present two novel approaches to alter a flight network for introducing new flights while maximizing airline's profit. A key feature of the first approach is to adjust the aircraft cruise speed to compensate for the block times of the new flights, trading off flying time and fuel burn. In the second approach, we introduce aircraft swapping as an additional mechanism to provide greater flexibility in reducing the incremental fuel cost and adjusting the capacity. The nonlinear fuel-burn function and the binary aircraft swap and assignment decisions complicate the optimization problem significantly. We propose strong mixed-integer conic quadratic formulations to overcome the computational difficulties. The reformulations enable solving instances with 300 flights from a major U.S. airline optimally within reasonable compute times.