Monitoring Real-Time NAS Safety with State-Dependent Risk Models

NASA recently added real-time, system-wide safety assurance (RSSA) as one of its aeronautics strategic thrusts. As NASA, FAA, and industry introduce new technologies, concepts, and vehicles into a growing and evolving national airspace system (NAS), the need for monitoring of an increasingly complex, congested, and more automated system becomes greater. RSSA will develop risk models, methods, computational solutions, and prototype monitoring systems to move risk identification and mitigation from weeks and months to real-time. The preliminary RSSA technology roadmap identifies the need for real-time NAS-wide status monitoring but does not describe how this information would be provided or used to assess real-time changes in safety risk. Our proposal aims to demonstrate how to accomplish those objectives and quantify risk for normal safe operations and degraded states, thereby accelerating RSSA milestones. Our approach enables real-time estimates of NAS risk and can also provide valuable insight into assessments of new technologies and procedures. FAA interest in this capability offers the potential for an FAA deployment platform by integrating the state-dependent risk models with an existing FAA safety analysis and monitoring tool, the Integrated Safety Assessment Model (ISAM).