Navigating the Uncertain: Integrating Uncrewed Aircraft Systems at Airports in Uncontrolled Airspace

The introduction of fixed-wing cargo Uncrewed Aircraft Systems (UAS) has the potential to revitalize traffic at under-utilized regional airports. These regional airports are often non-towered airports in uncontrolled airspaces with increasingly non-cooperative air traffic. This work proposes to adapt current U-space architectures for the terminal airspace of these airports. This will reduce traffic intent uncertainty as all airspace users must be electronically conspicuous to the U-space environment. To further mitigate traffic intent uncertainty in uncontrolled airspaces, this paper analyzes the spatial traffic density of crewed traffic at four German non-towered airports in 2022. The investigated flight routes and traffic patterns of crewed traffic help to understand current flight intents and enable a more seamless airspace integration of UAS together with crewed traffic. In addition, this paper introduces a UAS holding stack concept for non-towered airport approaches within a U-space environment. UAS holding stacks are intended to handle increased traffic intent uncertainty in the context of tactical conflict management provided by U-space services. The results of this paper will enable more efficient airspace integration of UAS in terms of strategic and tactical flight planning and conflict management at non-towered airports.