The Air Traffic Management Risk Classification Scheme-Why so Difficult?

A risk classification scheme (RCS) for the design of complex safety critical systems is necessary to ensure that the required target level of safety can be demonstrated. The RCS is not be confused with "acceptable level of safety in the provision of ATS" (ICAO [3]) that determines the level of safety that is being achieved in service. This paper describes the difficulty of defining and validating a RCS.