Study on traffic scenarios: Interdependency of capacity, environment, and cost based on traffic forecasts

25 September 2023.- A recent study published by the InterFAB coordination platform lays great stress on the necessity of precise traffic forecasts and its influence on cost and resource planning. In the past, not only have air traffic forecasts turned out to be mostly imprecise, but there has been no study on the relationship between traffic forecasts and environmental aspects either. By using state-of-the-art methods, the present study finds answers to both aspects and determines interdependencies of capacity, environment, and costs. The study also emphasizes the need for a homogeneous database on an ANSP basis rather than a country-based one.

According to their sovereign tasks, air navigation service providers (ANSPs) are responsible for the safe and efficient operation of air traffic. For an efficient operation, it is necessary to predict the demand as precisely as possible. This also implies the efficient deployment of resources into account to ensure service provision at minimum costs to stakeholders. Therefore, resource planning relies on expected demand for a pre-set horizon. The optimum competes with sufficient resources for robust and safe operations, but minimum resources for cost-effectiveness.

In the early 1990s, EUROCONTROL started to assess the European ANSPs. In the currently valid performance scheme, four Key Performance Areas (KPAs) are defined: safety, capacity, cost efficiency, and environment. In the past years, regulators emphasized an enhancement of cost efficiency and capacity. However, social pressure (e.g., Fridays for Future) caused a shift towards environmental aspects of air traffic recently. As a consequence, the environmental indicators gain increasing importance in benchmarking exercises as well as their interdependency to other areas.

In October 2021, EUROCONTROL presented the most recent medium-term forecast, predicting traffic movements and service units for the years 2021–2027. Obviously, forecasting always inheres uncertainty due to global (e.g., financial crisis) or local (e.g., the Russian attack on Ukraine) events, leading to short-term changes in traffic demand. To cover these uncertainties, STATFOR published three scenarios (low, base, and high). However, it was proven that the forecast quality is very limited. To consider the low forecast quality, the InterFAB study created two additional scenarios (super-high, super low). For each scenario, flights are forecast for 2021–2027 at the ANSP level. For each ANSP, the expected resources and ATCO employment costs are calculated. The range between super-high and super-low scenario reflects the uncertainty regarding resources and costs. With regard to the costs of delay, the study shows that using average values as done in previous reports by the University of Westminster does not seem to be a good representation of the real costs, as not all flights are subject to the same amount of delay. Thus, it is crucial to determine the distribution of these delays and how they affect the total cost.

Furthermore, the InterFAB document discusses the following questions:

  1. How many ATCOs will be needed per year?
  2. How much total delay and/ or CRSTMP delay will be created per year?
  3. How much cost of total ATFM delay and/or CRSTMP delay for airspace users will be created per year?
  4. What are the forecast values for Horizontal Flight Efficiency (KEA and/or KEP) per year?
  5. What is the total amount of CO2 emissions forecasted?
  6. What is the total amount of climate costs (and potentially other environmental costs) per year?

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For more information, please, contact:

Dr Matthias Whittome,