Total system error performance of drones for an unmanned PBN concept

The German Aerospace Center (DLR) operates small drones i.e., octocopters for research purposes at different institutions at different locations. In addition, the DLR is working on the integration of drones into unsegregated airspace in several national and international projects. One of the key elements for a safe integration of drones is the positioning capability of the air vehicle. On the one hand it is required for geofencing applications in order to create no-fly zones and on the other hand it is required to generate an airspace management for unmanned traffic. In recent years, the Performance Based Navigation (PBN) concept was introduced for manned aviation to exploit the navigation performance of modern satellite navigation and to manage the available airspace. One approach for Unmanned Aircraft System (UAS) Traffic Management (UTM) is obviously to transfer the PBN concept for drone applications. However, as drones usually use commercial off the shelf equipment that is usually not certified for aviation applications, the question is how the basic principle can be transferred. In this work, we used a commercial octocopter (MikroKopter MK Okto XL 6S12 ARF) to assess the horizontal Navigation System Error (NSE) as well as the lateral Total System Error (TSE) while using different GNSS receivers. The horizontal navigation is based on GNSS in stand-alone mode or using SBAS augmentation and a compass for directional information aid. No additional sensors like inertial measurements are used here. We are going to present the results from flight trials with two different GNSS receivers and will draw conclusions for a PBN concept for drones.