Even with the help of the latest in forecasting technology, weather can be difficult to predict. This is especially a problem for air traffic management, which requires an accurate picture of the weather outlook to ensure smooth traffic flow.  Partners have concluded a two-year EU-funded research project on how to improve air traffic predictability by better factoring in weather forecast uncertainties. Funded by the SESAR Joint Undertaking within the framework of Horizon 2020, the TBO-Met project  brought together researchers from Universidad de Sevilla (Spain), Universidad Carlos III de Madrid (Spain), Paris Lodron Universität Salzsburg (Austria), MeteoSolutions GmbH (Germany), and the Spanish meteorological office AEMET (Agencia Estatal de Meteorología).

Uncertainty is part and parcel of air traffic management. There are several factors that cause uncertainty, principle among them is weather. And with uncertainty comes disruption. It is estimated roughly 20% of delays in Europe are weather related, with EUR 159 million in estimated costs. In addition, weather phenomena such as hail, severe icing and lightning are significant weather hazards and can also inflict significant damage to aircraft equipment and windscreens. Also, the declared capacity of the system (number of aircraft that can be processed) is generally affected by weather uncertainty as well, roughly by 10%.

At European level, the ambitions of the Single European Sky initiative (with SESAR being its technological pillar) for 2035 are - compared to the 2005 baseline- to triple the air space capacity, to improve air traffic safety by a factor of 10, reduce aviation environmental impact by 10%, and reduce the overall cost of air navigation service provision by 50%. To this end, uncertainty levels in air traffic (in particular weather related) have to be reduced and new strategies to deal with the remaining uncertainty must be found.

The overall objective of TBO-Met was twofold: to advance in the understanding of the effects of meteorological uncertainty in air traffic, and to pave the road for a future integration of meteorological uncertainty management into the air traffic domain. To reach these goals, the project has focussed on the three following problems, which define its scope: trajectory planning at mid-term level considering weather forecast uncertainties, short-term trajectory prediction under thunderstorm activity (storm avoidance problem), and sector demand analysis considering weather forecast uncertainties.

The overall outcome of TBO-Met has been the development of methodologies to analyse, quantify and manage the effects of meteorological uncertainty on air traffic management. The three methodologies developed have the following capabilities: to find a trade-off between cost-efficiency and predictability and/or exposure to convective risk of aircraft trajectories, to provide relevant information for an efficient storm avoidance strategy, and to predict the sector demand uncertainty based on the uncertainty of the individual aircraft trajectories.

Results have shown that, by considering the uncertainty of weather predictions, the predictability of aircraft trajectories can be increased, the storm avoidance strategies can be better anticipated by

pilots and controllers, and the accuracy of sector demand forecast can be improved. More specifically, the potential benefits are the following: reduction of the buffer times used by airlines, better-informed decision making, increase of declared sector capacities, and better identification of demand-capacity balancing measures.

TBO-Met (Meteorological Uncertainty Management for Trajectory Based Operations) Project has received funding from the European Union’s SESAR H2020, under grant agreement 699294.