Physics based risk assessment of launch vehicles

To provide NASA with the most comprehensive and sophisticated launch vehicle risk modeling system possible, a physics-based approach that models dynamic failure processes using systems and environmental variables has been developed and implemented in a collaborative engineering environment. The methodology is an extension of, and a departure from conventional, well-known techniques used to evaluate risk in complicated systems, such as fault-tree and event-tree analysis. This approach has been used to analyze the main risk drivers for NASA's Next Generation Launch Technology program launch vehicles. This paper describes how this methodology is used to assess launch vehicle risks with examples from the thermal protection and main propulsion system.