Simulation-Based Airspace Accessibility Analysis for Integrating Regional Unmanned Aircraft Systems into Non-Towered Airport Traffic Patterns

Unmanned aircraft systems for regional operations are assumed to frequently operate at non-towered airports, where routine integration remains challenging due to limited separation principles and partially observable manned traffic intent. This research investigates tactical procedures for integrating unmanned aircraft into non-towered airport environments, where unmanned aircraft must interact with manned traffic under procedural constraints. A simulation framework is developed that combines historical traffic data with standard traffic pattern procedures and rule-based decision-making to integrate unmanned aircraft at non-towered airports. The simulation logic includes detection of manned traffic activities, rule-based queuing, and airspace capacity constraints. By varying detection look-ahead times (60/120/180 s) and unmanned aircraft traffic rates (15/30 min), the simulation quantifies terminal airspace accessibility and derives metrics that capture throughput (no conflict versus deconflicted holding flights), delay propagation (holding minutes and holding orbit counts), concept feasibility (aborted/denied holdings), and altitude band utilization. The results show a consistent safety versus throughput trade-off with longer look-ahead times increasing holding demand but reducing the share of aborted holdings, while higher traffic volumes amplify holdings and delay. Holdings are predominantly conducted in the lowest available holding altitude at 2500 feet above the ground, with occasional multi-layer use to handle traffic peaks.