Civil aviation is a multi-trillion-dollar market projected to grow continuously until at least 2040. Aircraft navigation and guidance from terminal to terminal is the determining cost factor for individual flights. Thus any savings resulting from the introduction of new digital technology will yield an extremely high return on investment due to economies of scale. This course outlines the specific navigation context before identifying where conventional navigation means (flight routes) are insufficient for achieving further increases in capacity, flexibility and performance. The concept of performance-based navigation (PBN) is outlined and why positioning needs to be available everywhere (area navigation - RNAV). The GNSS basic positioning principle is described and the relatively frequent satellite failures and anomalies are explored which are the reason why stand-alone GNSS cannot be used directly for a safety-critical application. The concept of solution separation statistics combined with the use of multiple GNSS constellations is introduced (Advanced Receiver Autonomous Integrity Monitoring – ARAIM) which in the long term may replace conventional navigation technology. The lecture concludes with a look at limiting factors, the current planning of civil aviation authorities and the European GNSS Galileo project. - Lecturer: Professor Thomas Pany (Universität der Bundeswehr München).