Modeling the airspace spare capacity to foster a cooperative resilient air traffic management system

A critical challenge in configuring a sustainable and efficient air transport system in Europe is overcoming the persistent shortage of airspace capacity, which often results in sector-level Air Traffic Control (ATC) regulations. These measures disrupt traffic flows, complicate planning, and reduce overall network performance. This paper introduces the Clusterized Aircraft Early Handover (CAEHO) mechanism as an innovative capacity-on-demand solution to mitigate sector overload by delegating control and communications of eligible aircraft to adjacent sectors with available spare capacity. The concept is consolidated and advanced through three major contributions. First, CAEHO is formally introduced and its scalability is validated for the first time across the European Civil Aviation Conference (ECAC) airspace. Second, a methodological framework is developed to quantify the spatial distribution of spare capacity around overloaded sectors. Third, CAEHO’s performance is stress-tested by progressively increasing sector load, assessing robustness under varied operational conditions, including dwell-time constraints, and conflict detection. The study also formalizes operational requirements and parameter thresholds, evaluating their effect on efficiency and delegation outcomes, and characterizing the trade-off between candidate availability and conflict-free eligibility across different remaining dwell times. Results show that CAEHO can mitigate a substantial fraction of ATC-capacity regulations while preserving flight trajectories. However, performance can be constrained by conflict detection, highlighting sensitivity to dwell time and traffic conditions. The ECAC-wide analysis supports the mechanism’s novelty, operational feasibility, and potential to enhance resilience and efficiency in the European ATM network. • CAEHO: early handover of clusterized aircraft, a capacity-on-demand methodology to avoid ATC capacity regulations. • Large-scale CAEHO deployment across the European Civil Aviation Conference area. • Framework to locate and use spare capacity in adjacent sectors. • Stress-tested by increasing the load in overloaded sectors, with conflict detection. • Overall CAEHO performance assessed for ECAC area operations.