After safety, punctuality is the most important indicator of how well the ATM sector is performing. Punctuality has now reached a level unimaginable at the end of the 1990s. In 2017, 80 percent of flights landed on time compared to 81 percent in 2016.

The most reliable information on delay metrics is provided by the Central Office of Delay Analysis (CODA). The office collects flight-by-flight data from airlines, highlighting the cause and duration of delays to each flight, using the IATA delay coding system. 

At its core, the causes of the delay problem are structural; the so-called “reactionary” delay – the knock-on effect of prior delays – is by far the most common cause of delays (44.1 percent). A further indication of the increasing sensitivity of the aviation system is that the primary causes of delays have increased across the board. According to CODA, 45.4 percent of delays can be attributed to airlines. 27.5 percent are due to air traffic flow measures (ATFM). Climate change is also playing an increasing role: adverse weather led to 8.3 percent of all delays. These numbers show that aviation – with its precisely scheduled processes and tight interplay between airlines, airports and ANSPs – is becoming increasingly sensitive to even small disruptions.

ATFM is the indicator used to assess the contribution to delay attributable to air traffic management. Unlike the figures from CODA, this metric does not show if an aircraft landed on time but simply shows if a flight were delayed by flow management measures imposed by air traffic control (ATC). This means it is possible for a flight to be delayed by ATC but still land on time.

In 2017, 92.9 percent of all flights (2016: 94.1 percent) experienced no delays caused by ATC as measured by ATFM en-route delays in FABEC airspace. Nevertheless, 97.4 percent arrived at their destination airports within 15 minutes of their scheduled time. Consequently, the overall delay minutes caused by flow management measures increased by 11.5 percent (2017: 69 seconds per flight; 2016: 64 seconds per flight). FABEC missed the target of 25 seconds per flight. The principal causes of ATC delays are shortages in capacity (42.3 percent) and staffing (15.7 percent) – both mainly due to a mismatch between unpredicted traffic and long-term staff and capacity planning. Furthermore, the impact of climate change is increasing and becoming more visible for passengers in terms of thunderstorms or airport closures as a result of snow on the runways. In 2017, 22.9 percent of all delays were caused by adverse weather. The impact of industrial action decreased substantially, causing just 10 percent of the overall delay.

Aviation Facts

FABEC ANSP Performance 2016

External data sources

Central Office of Delay Analysis
More information on CODA
CODA Report 2016

Network Manager
More information on the Network Manager
Annual Network Operations Report 2016

Performance Review Unit