ABSTRACT
In order to learn from the past in complex, dynamic systems their factual functioning must be transparent. Knowledge deficiencies and systemic deficiencies should be derived from analysing decision-making and underlying assumptions, uncertainty and knowledge. Such deficiencies are to be identified throughout the design process as well as during operational practices, in order to facilitate systems change and enhancement of the safety performance. Safety investigations should facilitate evidence-based learning. Without a fact-finding mission dealing with on-site observations and interpretations, evidence-based learning will be lacking and achieving consensus will be reduced to a mere negotiation result. Providing evidence is the domain of forensic sciences. By providing a timely transparency, safety investigations may take the role of providing functional requirements for the (re-)engineering design of resilience as a system property. This approach is demonstrated by two major case studies that have been conducted in the Netherlands: the El-Al air crash in Amsterdam and the inquiry into the High Speed Line ERTMS signalling system.
