Currently, there is limited discourse surrounding the safe operational planning of UAVs within complex multi-stakeholder urban environments. This paper conceptualises a methodology for prototyping a decision support system for urban UAV flight operations planning. The proposition is based on integrating urban 3-dimensional data with the physical factors of UAV flight operations. A simulated, holistic understanding of UAV usage in urban space emerges, enabling better informed decisions by planners around safe flight operations. The feasibility, applicability and benefits of the decision support system and associated policy implications for urban planners and UAV users are discussed scoping further development of this approach.