Augur: RAIM for dummies

When pilots want to fly Basic Area Navigation in Europe using the Global Positioning System (GPS) they will have to check whether this can be done safely. Augur can perform such a check by predicting whether GPS can provide sufficient positioning integrity; in case it cannot, flight dispatch should not be made. Although Augur performs complex calculations, it can be used without in depth knowledge on GPS. Still, the serious safety consequences of misuse or misinterpretation of Augur´s output definitely justify attempts to enable the user to understand why GPS operation can be performed safely or not. This paper therefore aims at providing people without a specific background in GPS with sufficient insights to fully exploit the information disseminated by Augur. It does so by explaining the way Augur operates “under the hood” without assuming extensive knowledge on either GPS or on the technique that is used to provide integrity, called Receiver Autonomous Integrity Monitoring (RAIM)