Frontlog scheduling in aircraft line maintenance: From explorative solution design to theoretical insight into buffer management

Based on a multi-year research engagement with practice, we present a novel solution design for frontlog scheduling in aircraft line maintenance and offer theoretical insights into buffer management in operations. The field problem of the case airline was to improve departure reliability for long-haul aircraft without increasing maintenance resources, and without using backup aircraft. Frontlog scheduling is the purposeful introduction of over-maintenance as a buffer of maintenance tasks that can be opportunistically postponed. A detailed simulation of the solution introduced in the airline's operations indicates a performance frontier shift, concurrently improving departure reliability, and reducing maintenance cost. We position the novel practice in operations and maintenance management literature, arguing that the frontlog creates a new type of time buffer, available in contexts where capacity serves predictable as well as unpredictable demand. Further theoretical elaboration leads us to reconceptualize buffer management along time and capacity dimensions, reducing inventory to a special case of time buffering.