Integrating Existing Safety Analyses into SysML

Migrating systems and safety engineering (often with legacy processes and certified tools) towards a modelbased systems engineering (MBSE) environment is a socio-technical problem. Establishing a commonconceptual framework requires agreement on modelling artefacts and the integration of existing tool chainsto minimise disruption. We discuss our experience integrating a SysML Safety Profile to model fault treesbut which has the prerequisite requirement to continue the analysis of those models by existing tools. Wedemonstrate a lightweight profile that minimally captures the fault logic for a Rolls-Royce gas turbineengine controller and provides specific in-house extensions for both fault tree and engine dispatch analysisby exporting model entities and relationships from the SysML fault trees. During integration we realised amore fundamental need to reconcile the systems engineers’ functional view with the safety engineers’focus on failure modes and fault logic in order to maximimse the longer term benefits of MBSEdevelopment.