Sensitivity Investigation of Fault Tree Analysis with Matrix-Algebraic Method

The Fault Tree Analysis (FTA) is a systematic, deductive (top-down type) and probabilistic risk assessment tool which shows the causal relations leading to a given undesired event, referred to as the “Top Event” (TE). The events, which cannot be subdivided, are called the Basic Events. Fault Tree diagram displays the undesired state of the investigated system (top event) in terms of the states of its components (basic events). The Fault Tree Analysis is a graphical design technique main result of which is a tree, a dendritic graph. Probabilistic Fault Tree Analysis (PFTA) is a quantitative analysis method used to calculate the probability of Top Event from given failure probabilities of system components. The objective of the sensitivity analysis is to show how the change in any system parameter influences the resultant reliability value of the whole system. The main aim of this study is to elaborate an easy-used algorithm for setting-up of Linear Fault Tree Sensitivity Model (LFTSM). This modular approach process uses matrix-algebraic method based upon the mathematical diagnostic modeling of aircraft systems and gas turbine engines. The paper shows the adaptation of linear mathematical diagnostic modeling methodology for setting-up of LFTSM and its possibility of use to investigate Fault Tree sensitivity by a demonstrative example.