Conceptual Development of Terminal Airspace Integration Procedures of Large Uncrewed Aircraft Systems at Non-Towered Airports

Uncrewed aircraft systems are expected to revitalize traffic activities at under-utilized airports. These airports are often located in uncontrolled airspace and do not have an operating control tower to provide separation services for approaching aircraft. This presents unique challenges for the integration of uncrewed aircraft at non-towered airports. This paper offers a methodology to systematically assess traffic activities and quantify flight behaviors of crewed aircraft using historical flight data. To integrate uncrewed traffic in high-density traffic scenarios or during off-nominal flight situations, this paper assesses the concept of a holding stack above the traffic pattern airspace to handle increased traffic uncertainty and to provide safe integration procedures. Twelve non-towered airport environments, relevant for initial uncrewed cargo operations across Germany, California, and Texas, are investigated to assess concept feasibility and real-world implementation. Based on the interaction of various quantitative measures, results are presented on the feasibility of holding stacks in the terminal airspace and the influence of crewed aircraft’s historical flight behavior on different integration procedures for uncrewed aircraft. The analysis of various measures suggests that six airports are comparatively suitable candidates for holding layers above the airport traffic pattern, with holding altitudes to start between 2500 and 3500 feet above the ground.