How reliable is satellite navigation for aviation? Checking availability properties with probabilistic verification

This paper highlights a promising application of the analysis technique of probabilistic verification. We prove that it is able and suitable to analyse GNSS based positioning in aviation sectors for aircraft guidance. In particular, the focus is a widely used formal method called probabilistic model checking, and its generalisation to the analysis of quantitative aspects of a specific civil flight. We construct a formal model of the GNSS based positioning system for this application in the probabilistic π-calculus, a process algebra which supports modelling of concurrency, uncertainty, and mobility. After that, we encode our model in language of the PRISM symbolic probabilistic model checker. We then formalise and analyse the logical properties that relate to the dependability of the underlying system to check the system reliability and availability. We demonstrate how model specification and verification techniques can be successfully applied to the reliability and availability analysis of our case study.