The European Organisation for the Safety of Air Navigation, EUROCONTROL, is an international organisation that works to achieve safe and seamless air traffic management across Europe. They have published July 2024 figures for traffic in the European aviation network and given insight into the reason behind flight delays across the network.
In July 2024, traffic in the European aviation network was +4.5% compared to July 2023, with an average of 34,379 flights per day.
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 southeast: Serbia/Montenegro (+31%), Croatia (+29%), Austria (+23%), Hungary (+22%), Greece (+20%) and Bulgaria (+16%). Also, places such as Italy (+12%), Türkiye (+12%) and Spain (+11%) are well above pre-pandemic levels.
Understanding Air Traffic Management
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, 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 of an average of 6.5 min/flight
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.
weather-related ATFM delay per flight (2.4 min/flight)
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. The significant traffic increase in key parts of the network has been a major factor.
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 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.
Increasing Weather-Related Delays
The increasing weather-related delays have been an area of particular focus this summer and EUROCONTROL advise that they 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 (versus 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.
Background
The air navigation service providers (ANSPs) that are responsible for air traffic control provide EUROCONTROL with an overview of the number of air traffic control sectors they have available and the number of aircraft they can safely handle at any one time in those sectors. Airlines provide EUROCONTROL with their flight plans, indicating where they plan to fly. If more aircraft are planned to be in any one area than can safely be handled, EUROCONTROL works with the air traffic control centre, the airlines and other operational partners to try and find the best solution. Solutions include, for example, re-routing or opening of additional airspace. In some cases, to avoid an unsafe situation where there are too many aircraft expected at the same time in an air traffic control sector, EUROCONTROL will issue a departure slot delaying the flight on ground.
EUROCONTROL has been working closely with airlines, ANSPs, the military and airports to prepare for this summer, which was expected to be difficult due to known capacity issues. A series of actions were identified by EUROCONTROL together with the airlines, ANSPs, military and airports to address the challenges. These include:
- Improving adverse weather management
- Prioritising First Rotation
- Flight Plan Adherence
- Realistic schedules, including turnaround times
- Delivering agreed capacities
Key figures in July 2024
- There were 1,065,758 flights overall in the European network compared to 1,020,071 in July 2023, an increase of v4.5%.
- ATFM delays per flight have increased by 64% compared to this period in 2023. This rise was in part as a result of an increase in weather delay per flight – from 1.7 minutes to 2.4 minutes.
- Arrival punctuality (within 15 minutes of scheduled time) – which reflects all causes of delay, not just ATFM – was slightly worse than in 2023 at 61%.
| Network in July | |||||
|---|---|---|---|---|---|
| 2019 | 2023 | 2024 | Change from 2023 to 2024 | Change from 2019 to 2024 | |
| Traffic | 1,093,734 | 1,020,071 | 1,065,758 | +4.5% | -2.6% |
| Air Traffic Flow Management delay (minutes) | 4,393,349 | 4,221,925 | 6,940,504 | +64% | +58% |
| ATFM total delay/flight | 4.0 mins | 4.1 mins | 6.5 mins | +58% | +62% |
| ATFM weather delay/flight | 1.3 mins | 1.7 mins | 2.4 mins | +41% | +84% |
| ATFM capacity delay/flight | 1.6 mins | 1.2 mins | 2.6 mins | +117% | +62% |
| AFTM staffing delay/flight | 0.8 mins | 0.7 mins | 0.7 mins | – | -12% |
| Arrival punctuality | 73% | 63% | 61% | -2 pp* | -12 pp* |
* percentage points
