Large scale distributed visualizations are routinely used by organizations in both the commercial and government sectors for training and simulation. These simulations are of particular importance in the research associated with the United States Federal Aviation Administration's current work on updating the National Airspace System to the Next Generation Air Transportation System. This new system will include the integration of unmanned aerial systems into civil airspace for routine flights. In this paper we propose a system for integrating unmanned aerial system visual observers into the distributed simulation capability of the Federal Aviation Administration using large-scale virtual reality systems. We demonstrate the replication of terrain surrounding flight tests in virtual environments and the generation of the observer's views from both ground-based and airborne scenarios.