EUROCONTROL's predictive RAIM tool for en-route aircraft navigation

The Navigation Division of the EUROCONTROL Agency, with STASYS Ltd and Delft University, has developed the AUGUR Programme for B-RNAV (Basic Area Navigation). AUGUR is providing aircraft operators with availability of Global Positioning System (GPS) Receiver Autonomous Integrity Monitoring (RAIM). Its design was a particular challenge, as an algorithm had to be defined which was a suitable representation of those used in on-board systems, and the tool had to be accessible by a large number of aircraft operators. The Internet was chosen as the means of data dissemination, and so AUGUR is one of the first Internet-based tools for aircraft operations in Europe. This paper aims to describe the requirement, design, testing and operation of AUGUR. Issues such as computing power, location selection, hardware selection, interface and data promulgation are discussed. The discussion of the requirement includes an overview of the GPS B-RNAV safety assessment.