Sydney (SYD) airport has well publicised operational constraints including a nighttime curfew and a cap of 80 aircraft movements (arrivals and departures per hour). It operates three runways, the parallel 16/34 runways, and the “cross-wind” runway 7/25. These runways are used in several different combinations resulting in several different operational “modes”. Particular modes are preferred during certain times of the day due to noise mitigation procedures, for example, “mode 1” using 34L for arrivals and 16R for departures is the preferred mode during the curfew (during which a limited number of operations are allowed). When weather conditions necessitate the use of some modes, a reduction in aircraft movements is required. This includes when intersecting runways or a single runway are in operation.