The 75th Percentile performance figures for airborne delay at Melbourne are indicated in Figure 5. January performance (5.0 minutes) did not meet target (3.5 minutes) and performance was worse than the same period last year (3.6 minutes). The long-term trend for airborne delay at Melbourne is upwards.
Figure 5: Melbourne Airborne Delay 75th Percentile Notable events
Click image to enlarge
The following commentary describes the most significant Airborne Delay events (10) during January in Melbourne:
- 07 Jan – Runway 16 unserviceable due to nose-wheel collapse (1600 – 1900 local)
- 12 Jan – Thunderstorm followed by low visibility (1500 – 1600 local)
- 15 Jan – Low visibility (0800 – 1200 local)
- 19 Jan – Wind and Level 1 revision (1600 – 1900 local)
- 20 Jan – Low cloud (0700 – 1000 local)
- 22 Jan – Low cloud (0800 – 1200 local)
- 25 Jan – Thunderstorms (0700 – 1000 local)
- 26 Jan – Low visibility and Level 2 revision at 0800 (0700 – 1200 local)
- 28 Jan – Thunderstorms (1500 – 1900 local) Network Performance Report – January 2018 . Page 10 of 26
- 29 Jan – Thunderstorms followed by low visibility. Level 2 revision at 0700 (0700 – 0800 local)
The event on 25 January resulted in significant Airborne Delays of 16 minutes (75th upper percentile) between 0600 and 0900 local and was subject to a detailed analysis (Appendix A). A significant factor in this event was the arrival of 12 international aircraft during the three hour period. The actual arrival times of these international aircraft was between 18 and 59 minutes different from their calculated landing time (i.e. slot in Harmony). The situation was compounded by weather conditions that impacted on capacity and which resulted in a situation where demand and capacity where evenly matched through the period.
In periods where demand and capacity are evenly matched, the effectiveness of the ATFM program is reduced by the presence of international aircraft where the actual landing time is vastly different to the calculated landing time. The Long Range ATFM project will provide a solution to increase international arrival predictability and adhere closer to their assigned arrival slot. Further detail on the 25 January event can be found in the full review in Appendix A.