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Research questions


The effective integration of micro and macro models in the APACHE framework will allow capturing the complex interdependencies among KPAs, which in turn will shed some light on the following (initial) research questions:

  • With regards to the limits of flight efficiency, how much fuel and emission reductions can be achieved by enabling user-preferred free routes at EU-wide level? If the aircraft operators can fly their optimal trajectories without any fixed ATM or airspace constraint (i.e., free routing including continuous cruise climbs)?
  • What is the expected impact in safety and capacity if free routing and/or continuous cruise climbs are implemented? Which are the capacity needs (in terms of number of sectors and configuration) to implement these in Europe if trajectories could be strategically de-conflicted to reduce complexity at sectors?
  • With regards to the limits of ATM cost-efficiency, what is (approximately) the minimum number of sectors needed to support the current operations and traffic demand to minimize ATFM delays? And to support Free Routing or continuous cruise climbs at EU-wide or FABs level? And what if the level of demand is a 50% higher, as forecasted for 2035?
  • With regards of ATM KPAs, can we estimate the Pareto-front? That is to obtain a representative set of equally efficient solutions in such a way that it is impossible to make any improvement in one particular KPA without making at least one other KPA worse.
  • In the presence of typical sources of flight uncertainties, such as wind prediction errors or airport delays, which might be the expected impact in predictability and robustness of the planning? Which strategies could be implemented to increase predictability and robustness and what might be the impact on other KPAs?