Modeling safety and airworthiness (RTCA DO-178B) information: conceptual model and UML profile

Several safety-related standards exist for developing and certifying safety-critical systems. System safety assessments are common practice and system certification according to a standard requires submitting relevant system safety information to appropriate authorities. The RTCA DO-178B standard is a software quality assurance, safety-related standard for the development of software aspects of aerospace systems. This research introduces an approach to improve communication and collaboration among safety engineers, software engineers, and certification authorities in the context of RTCA DO-178B. This is achieved by utilizing a Unified Modeling Language (UML) profile that allows software engineers to model safety-related concepts and properties in UML, the de facto software modeling standard. A conceptual meta-model is defined based on RTCA DO-178B, and then a corresponding UML profile, which we call SafeUML, is designed to enable its precise modeling. We show how SafeUML improves communication by, for example, allowing monitoring implementation of safety requirements during the development process, and supporting system certification per RTCA DO-178B. This is enabled through automatic generation of safety and certification-related information from UML models. We validate this approach through a case study on developing an aircraft’s navigation controller subsystem.