Tradeoffs between Safety and Efficiency from Dynamic Airspace Geofencing for Advanced Air Mobility

Airspace geofencing is a prominent capability that can support a safe integration of Advanced Air Mobility (AAM) operations in controlled airspace. In this paper, we develop a high-fidelity simulation framework to provide a quantitative performance assessment of dynamic geofencing in dense metroplex airspace. We apply the framework to the Sao Paulo metroplex in order to quantify the value of establishing keep-out geofences for increasing safety, while evaluating the associated impacts on AAM flight trajectory efficiency. Our framework encompasses several modules for realistic air traffic demand modeling, geofencing allocation and flight trajectory planning. A probabilistic model learned from actual flight trajectory and meteorological data is used to simulate the spatiotemporal distribution of conventional traffic patterns in the metroplex airspace and to construct the keep-out geofences to be avoided by AAM flights. Ground mobility data is leveraged to model AAM demand, considering daily commuting as a potential use case. Monte Carlo experiments are performed to simulate aircraft trajectories in the metroplex environment for various scenarios of geofencing application. With an appropriate spatial resolution, we find that dynamic geofences have the potential for significantly reducing the number of conflicts at a reasonable efficiency loss of less than 10% for AAM flights.