We investigate strategies for management of conflicts among autonomous unmanned aerial vehicles (UAVs) in high-density very low level (VLL) uncontrolled airspace. We consider deconfliction procedures which do not involve horizontal maneuvers, and study two types of airspace structure: single- and multi-layered airspace. We compare different deconfliction paradigms by simulating a busy day of operations over a geographical area. Our main contributions are a proposal of new deconfliction schemes for UAVs and an assessment of the single- and multi-layered airspace designs. Our work aims to provide regulators and policy-makers with a framework for choosing between resolution strategies for the airspace management.

We study separating urban unmanned aerial vehicles (UAV) traffic into altitude levels, using a PBN-inspired approach in which low-density airspace has few layers while congested areas in the city center are split into a larger number of layers. Navigating in the many-layers environment may require better vehicle equipage to support higher performance in terms of altimetry precision; our work thus follows the stakeholders encouragements to use performance-based navigation (PBN) in UAV traffic management (UTM). We present results for several traffic volume scenarios over Norrköping municipality in Sweden, demonstrating applicability of our solutions in a city setting.

Merging and splitting control sectors is a certified way to address demand-capacity imbalances in an airspace: during high-traffic hours a sector is split into two or more smaller sectors, while in low-traffic hours the parts are merged back. In this paper we explore ways of splitting a sector with simple straightline cut so as to balance, as well as possible, the number of controlled aircraft in the obtained smaller sectors. The approach is verified by computational experiments with enroute traffic over Swedish airspace.