U.S. airlines are continuing to add buffer time to published schedules, turning block time into a control lever for on-time metrics and network stability. The latest analysis uses Department of Transportation data across the top twenty cities and shows that identical city pairs can carry different scheduled durations by carrier.
That matters because padding changes the commercial signal in the timetable. It affects comparisons between operators, masks part of the operational variance in the system, and creates a structural tradeoff for planners balancing punctuality against fleet utilization.
The pattern points to a sector that is still optimizing reliability through schedule design, not only through hardware, software, or dispatch discipline.