In the context of the damage tolerance approach used to drive aircraft maintenance operations, it is essential to demonstrate the reliability of NDE inspections in detecting structural damage. The Probability Of Detection method, that links the probability to detect a detrimental flaw to its size is generally used for that purpose by giving the maximum flaw size that an NDE process can miss with a given level of probability and confidence. To be statistically valid, this approach requires a sufficient amount of data which is often difficult (and costly) to obtain with a purely experimental approach based on mock-up tests. Numerical simulation can be particularly useful at that stage thanks to its ability to give a very large amount of data at a relative low cost, which constitutes the so-called Model Assisted POD approach. Recent developments have even enhanced this capacity thanks to the implementation in CIVA simulation software of metamodels. On top of providing data for POD curves, simulations and metamodels can be also used at the design stage to optimize inspection methods and procedures and target a given POD for a given flaw size. It can also conduct extensive studies on parameters influence on the result, or to achieve sensitivity analysis. This communication illustrates, with some examples based on CIVA, how simulation can help to support NDE reliability studies in aerospace applications.

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