Identification and Quantification of Hazards Caused by Uncontained Engine Rotor Failure

One approach based on AC20-128A is presented in order to assess the risk caused by uncontained engine rotor failure (UERF). In this approach, the risk assessment procedure includes hazard identification and hazard quantification. In the step of hazard identification, the catastrophic functional hazards, derived from the functional hazard analysis (FHA) results for the airplane, are used as the top events to construct the fault trees. The minimal cut sets (MSCs) of the fault trees are the hazards to be identified exactly. In the step of hazard quantification, the probability of one hazard triggered by some uncontained debris is evaluated. After the probabilities of all the identified hazards are quantified, the risk assessment of the airplane is completed. And the assessment result is compared with the design specifications to show compliance with the safety design. A small example is introduced to illustrate the rationality and accuracy of the aforementioned method.