In order to investigate the interim dry storage facility for nuclear spent fuel is safe and reliable under credible external accidents caused by human induced, it is important to use a probabilistic safety assessment approach for evaluating the severity of an aircraft strike scenario. This paper gives an evaluation method of aircraft risk model by defining a reference case study that includes a given cask model with carefully selected impact conditions from literature based on a quantified manner. The analysis procedure is divided into three major consecutive parts: structural assessment of facility's wall, structural assessment of storage cask, and radiological consequence analysis. This paper presents an overview of the analysis procedure with a sample of calculations to provide an insight of probable risk level with brief technical explanations. This risk frame model would provide an efficient way to investigate the storage facility capacity against the aircraft crash and to protect the physical health of individuals and the environment.