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Efforts were undertaken jointly between PCC Airfoils and PCC Structurals Division to simulate solidification conditions and predict the occurrence of shrinkage and microporosity defects in Alloy 7 18 structural castings. The approach used finite element thermal analysis validated by experiments.An engine rail was selected as the demonstration part. A finite element thermal model was used to generate data on solidification conditions (i.e., solidification sequence, isochron, temperature gradient (G) and solidification rate (R)). A baseline condition was first established by matching model-predicted shrinkage locations with known inspection results for actual gating and casting conditions. A second model was then built for a casting with a different gating system to predict shrinkage locations prior to inspection. It was found that the shrinkage locations predicted by the second model match reasonably well with casting inspection results.