A Requirements Modelling Language to Facilitate Avionics Software Verification and Certification

Engineering avionics software is a complex task. Even more so due to their safety-critical nature. Aviation authorities require avionics software suppliers to provide appropriate evidence of achieving DO-178C objectives for the verification of outputs from the requirements and design processes, and requirements-based testing. This concern is leading suppliers to consider and incorporate more effective engineering methods that can support them in their verification and certification endeavours. This paper presents SpecML, a modelling language providing a requirements specification infrastructure for avionics software. The goal of SpecML is threefold: 1) enforce certification information mandated by DO-178C, 2) capture requirements in natural language to encourage adoption in industry. and 3) capture requirements in a structured, semantically-rich formalism to enable requirements-based analyses and testing. The modelling language has been developed as a UML profile extending SysML Requirements. A reference implementation has been developed and experiences on its application to an openly-available avionics software specification are reported.