Cross-modal conflict management: What can urban air mobility (UAM) learn from existing transport modes?

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Abstract

Recent advances in electric vertical takeoff and landing (eVTOL) aircraft, automation and intelligent transportation technologies are accelerating the emergence of urban air mobility (UAM) as a new low-altitude transport mode. As UAM operations become denser, more heterogeneous and increasingly automated, conflict management becomes essential for maintaining operational safety. However, UAM has not yet established a unified conflict management framework for future operations. This paper develops a cross-modal review framework to examine how mature transport systems can inform UAM conflict management. The review first compares conflict definitions, safety boundaries, and indicators across road, railway, maritime, commercial aviation, and UAM systems. It then reviews representative conflict management problems in mature transport modes and evaluates the transferability of their underlying mechanisms to UAM. The comparison shows that road traffic provides principles for structured corridor organization and local interaction control. Railway systems inform the allocation of constrained network resources over time. Maritime transport contributes encounter classification and responsibility assignment, while commercial aviation supports balancing demand and capacity and coordinating vertiport resources. However, these transfers must be adapted to UAM characteristics, including structured three-dimensional corridor operations, temporal occupation of ground and airspace resources, limited operational buffers, and dense automated multi-aircraft operations. A matrix based on seven criteria further classifies the mechanisms as transferable, conditionally transferable, or not transferable to UAM. These findings provide a structured basis for developing integrated UAM conflict management systems that are both safe and operationally feasible.

Graphical abstract

Keywords

urban air mobility / conflict management / cross-modal transfer / transport modes

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