Airspace Geofencing Volume Sizing with an Advanced Air Mobility Vehicle Performance Model

Airspace geofencing is a key enabler for versatile and safe low-altitude Unmanned Aircraft System (UAS) Traffic Management (UTM). Geofenced airspace volume sizing analysis is necessary to assure efficiency and safety for a broad suite of emerging UAS applications. Airspace safety buffer sizes can be determined and verified by modeling vehicle dynamics as well as quantifying guidance, navigation and control uncertainties. This paper proposes a methodology to design safety buffer sizes given specific vehicle and sensor properties and wind. These parameters are then translated to geofence safety buffer dimensions for straight and turning flight to statistically guarantee an aircraft will stay inside its flight trajectory based keep-in geofence. Vehicle, sensor, and wind parameters are tabulated and analyzed over a prescribed flight trajectory using a Computational Fluid Dynamics (CFD) analysis. Case studies using a small UAS model and a full-size advanced air mobility (AAM) aircraft model provide comparison of geofence volume sizings.