The objective of this research is to develop an analytic method that uses data on both accident and safety indicators to quantify the aviation risk which are caused by human errors. A specified proportional hazard model considering the baseline hazard function as a quadratic spline function has investigated and demonstrated its applicability in aviation risk assessment. The use of the proposed model allows investigation of non-linear effects of aviation safety factors and flexible assessment of aviation risk. A subset of data gathered from the Fight Safety Management Information System (FSMIS) developed by the office of the Taiwan Civil Aeronautics Administration (CAA) was applied to accomplish this study. The results demonstrate that the proposed model is a more promising approach with the potential of becoming very useful in practice and leading to further generalization of aviation risk analysis. (c) 2007 Elsevier Ltd. All rights reserved.