The 75th percentile performance figures for airborne delay at Sydney are indicated in Figure 6. January performance met the target for the median (0.5 minutes) and did not meet the target for the 75th percentile (3.7 minutes). Compared to the same month last year, there was an increase in the airborne delay median performance (from -0.2 minutes) and 75th percentile performance (from 1.9 minutes).
The long‑term (48-month) trend for airborne delay at Sydney is upwards. However, the 24‑month trend is flat.
Figure 6: Sydney airborne delay 75th percentile (last 24 months)
Click image to enlarge
(minutes – 75th percentile)
(Contributing causes to increased delays)
|05 January||15-22||11.5||Reduced capacity in afternoon and evening due to thunderstorms in the terminal manoeuvring area (TMA). Ground stop for flights to Sydney implemented at 1640L with a Level 2 GDP Revision conducted at 1817L (rates reduced).|
|08 January||20-21||2.6||Reduced capacity due to thunderstorm and runway change during evening peak period.|
|11 January||20-21||5.7||Reduced capacity due to thunderstorm during the evening peak period (tactical rates lowered).|
|18 January||09-22||2.8||Reduced capacity due to late-notice staff unavailability. Level 1 GDP Revision at 1100L with rates reduced. Numerous flight cancellations. Subsequent Level 1 GDP Revision at 0315L as additional staff became available (rates increased).|
|19 January||07-14||24.8||Reduced capacity due to late-notice staff unavailability. Harmony system outage prevented GDP Revision to lower planned rates. As a result demand for the morning exceeded tactical capacity.|
|21 January||09-11||8.5||Reduced capacity due to technical fault preventing use of Precision Runway Monitor. Tactical rates lowered.|
|23 January||08-09 &
|15.6||Reduced capacity due to thunderstorms in the morning (tactical rates lowered).
Concentration of demand due to late non‑compliant flights and off‑schedule internationals in late afternoon. Delay impacts compounded by emergency services operations.
|17-22||23.0||Reduced capacity due to thunderstorms in the late afternoon (tactical rates lowered).|
|31 January||18-22||21.3||Reduced capacity due to strong winds resulting in numerous missed approaches (tactical rates lowered).|