METHODOLOGY FOR EVALUATING AIRCRAFT CRASH IMPACT AND RELEASE
Introduction. This chapter establishes a set of guidelines and methods for calculating and
analyzing the impact frequency of aircraft crashes into a facility and the release frequency
for radioactive and/or hazardous materials. The approach to analyzing frequency is
divided into three parts:
Impact Frequency Evaluation: The fundamental analysis, based on estimating the
frequency of aircraft crashes into a facility. This provides basic frequencies for
subsequent screening and evaluation analyses.
Release Frequency Screening: An analysis based on including the structural
response evaluation in the impact frequency evaluation.
Release Frequency Evaluation: An analysis based on developing release
scenarios from the time of an aircraft crash until the time exposure occurs due to
the release of hazardous material.
The method used to estimate the frequency in each part is based on the same technical
principle; however, each part consists of varying degrees of complexity and conservatism.
After each part is completed, the results are compared with the guideline value given in
Chapter 4. If the result exceeds the guideline value, then additional analyses are
performed; otherwise, no further work is required beyond documenting the analysis.
The technical information provided in this chapter covers only the basic guidelines for
implementing the three parts, along with a description of the frequency estimation models
and the corresponding important input parameters for each model. Further technical
information required to perform the analysis is provided in Appendix B.
Detailed technical evaluations that support the development of each frequency model are
provided in the modeling and data technical support documents (References 1 and 2).
These support documents should be consulted if additional information on the specifics of