Implications of runway direction changes

4 December 2025

Implications of runway direction changes for improved arrival management at Singapore Changi Airport
^{E Asadi, G Enea, S Alam, M Schultz. SESAR Innovation Days}

This paper develops a runway-aware approach to improve the arrival management Singapore Changi (WSSS), where frequent weather-driven operating-direction changes cause time-varying airport capacity. Using Meteorological Aerodrome Report (METAR)-derived Air Traffic Management Advancement Program (ATMAP) scores, track-based direction detection, and rolling-hour sector-entry counts at a 170-NM reference ring, we first establish a stable baseline (5–20 Sep 2019, predominantly North operations) to construct a standardized capacity template. The effect of runway direction changes (flips) is then characterized via a compact parameterization: a small pre-flip capacity overshoot, a post-flip capacity trough, and followed by a brief capacity compensation bump. On a flip-rich day (25 Sep 2019, ten direction changes), the reduction in throughput begins 10–15 min before a change; early-morning flips produce deficits of - 8 to -15 movements/h for 45–60 min (up to 90 min when flips cluster), while mid-morning effects are milder ( -3 to -6/h for 30–45 min). Embedding this piecewise envelope in a metering optimization with Long Range Air Traffic Flow Management (LR-ATFM)-feasible time-shift options, we reduce the integral of overload from 2085 to 395 flight-minutes (-81%), with the maximum residual exceedance limited to 6 aircraft during the deepest morning trough. Results show that modest, upstream time adjustments aligned to runway-aware capacity trajectories can materially mitigate overloads without aggressive tactical intervention, providing an effective pre-condition of the flow for the Arrival Manager (AMAN).