Causal risk models of air transport - NLR-ATSI

following 6 levels: Government, Regulator, Company, Management, Staff and Work. The
scope of the causal risk model should encompass the primary and subsidiary processes
across all hierarchical levels from government down to work.
1.3. Directions for the reader
This thesis starts by explaining very briefly and superficially, the basics that are required
before the research question can be really addressed. A proper discussion on causal
modelling of aviation risk requires first a definition of the concepts of risk and safety in
Chapter 2 and in Chapter 3 an explanation of ‘causality’ in itself, including a description of
what constitutes a ‘causal model’. User needs are introduced in Chapter 4. The focus then
narrows to current practice beginning in Chapter 5 with a look at the way in which today
safety assessments for air transport are typically conducted. Chapter 6 follows with an
overview of other risk bearing industries with particular attention for the way in which risk
models are used in those sectors for managing and controlling risk. Comparison of current
practice with user needs is decisive in selecting modelling techniques to be used in causal
risk models. Different techniques and their characteristics are described in Chapter 7.
Quantification is often mentioned as one of the main problems and will be the topic of
Chapter 8. Three traditionally difficult subjects in risk modelling are described in Chapter
9: modelling human operators, modelling safety management and dealing with
interdependencies between various parts of the model, while the fourth, validation, is dealt
with in Chapter 10. All the ingredients are then available to come to a conclusion and to
answer the main research question, which is done in Chapter 11. Additional background
information is provided in the Appendices: Appendix A gives an overview of the history of
third party risk regulation at Schiphol airport. This information is relevant to appreciate the
context from which a call for causal risk models was explicitly generated. Appendix B
describes the main and subsidiary process in air transport. Appendix C gives information of
the CATS project. CATS is used throughout this thesis as an illustration of several issues.
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