Compared to 2019 traffic is at 97% and, with up to 20% of the Network’s airspace unavailable due to Russia’s full-scale invasion of Ukraine, nearly half (18) of the air navigation service providers (ANSPs) are managing exceptional increases in traffic (some of which was not forecasted) of more than 15% above 2019 levels, notably in the south east axis: Serbia/Montenegro (+31%), Croatia (+29%), Austria (+23%), Hungary (+22%), Greece (+20%) and Bulgaria (+16%). Other key parts of the Network, such as Italy (+12%), Türkiye (+12%) and Spain (+11%) are also well above pre-pandemic levels.
When the number of aircraft due to arrive at an airport, or to pass through a specific air traffic control sector, exceeds the available capacity as declared by the relevant airport/ANSP, the EUROCONTROL Network Manager will, in order to maintain safety, sequence the traffic by issuing a departure slot and holding some flights on the ground – an Air Traffic Flow Management (ATFM) delay.
ATFM delay for the month was 6,940,504 minutes, an average of 6.5 minutes per flight. Delays were 64% above those in July 2023. There was a combination of factors for these high levels of delay: saturation and a lack of capacity in parts of the network, significant convective weather (thunderstorms etc.), less airspace available for re-routings due to the war in Ukraine, increased military activity – and the major CrowdStrike outage on 19 July.
The weather-related ATFM delay per flight during July (2.4 min/flight) was over 40% more than in 2023. For safety reasons, aircraft avoid convective weather, reducing the number of aircraft flying through the affected airspace. As flights try to re-route into non-weather affected areas, there is a knock-on effect when these other areas are already operating in a saturated environment at the limit of their capacity – resulting in additional ATC Capacity delays.
ATC Capacity delays, where issues are known about in advance, accounted for 2.6 minutes/flight in July – more than double the 2023 figure of 1.2 minutes/flight. Here the significant traffic increase in key parts of the Network, such as the south-east axis, has been a major factor; some of this increase was not forecasted.
ATC Staffing, where there are fewer staff available on the day than planned, was in line with the 2023 figure, generating 0.7 minutes/flight (2023: 0.7 min/flight).
Delays, as experienced by the passenger, are composed of reactionary (knock-on) delays, airline scheduling delays and delays on the ground – as well as ATFM delays. Overall arrival punctuality, at 61%, was slightly worse than July 2023 (63%), reflecting the rise in traffic and the increased impact of adverse weather.
The increasing weather-related delays have been an area of particular focus this summer and we are seeing better cross-border collaboration. However, significant improvements are required; a more network-orientated approach to weather management needs to be adopted and implemented by summer 2025.
Some ANSPs have not delivered the agreed capacity and the EUROCONTROL Network Manager is actively working with them on urgently needed improvements. Other ANSPs have performed robustly, in some cases delivering more capacity than originally planned.
Other areas of focus for the Network Manager, such as scheduling and the prioritisation of the first rotation (to reduce knock-on delays for the rest of the day), have seen improvements. Airports in the network have focused on reducing average ground delay, with an improvement in performance of close to 5%. For the airlines, there has been a 30% improvement on scheduling (compared to July 2023) and a 5% improvement on first rotation performance.
In contrast, there has been a marked worsening of flight plan adherence. Compared to 2023, around 65% more flights are not adhering to their flight profile. This has a very negative double impact on ATC capacity, as the airspace capacity made available for these aircraft is not used and therefore is lost. The aircraft intrude on other airspace and use capacity that was not planned for them, resulting in ANSPs cutting declared capacity levels in order to safely handle the greater unpredictability.
Improvement in flight plan adherence is clearly required and this will be a key area of focus in summer 2025.
July’s performance demonstrates that there is an urgent need to introduce further structural improvements in preparation for summer 2025 and beyond, as regards:
- the Network Operations Planning Process;
- Capacity Delivery;
- Flight Plan Adherence; and
- a more network-focused approach to Weather Management.
There is also a clear, urgent and growing requirement to recruit and train more controllers to support an increase of capacity.
The EUROCONTROL Network Manager will continue to work intensively with all aviation stakeholders on improving the performance of the European Aviation Network – and to ensure that passengers get to their destinations safely and with the least possible delay.