Aircraft engine and airframe structural components that are machined from forgings represent a significant cost of both military and commercial aircraft.  Typical component applications are rotating disks in aircraft engines and structural components in airframes. The buy-to-fly weight ratio, which is the ratio of the forged material weight to the finished part weight, is typically between 4 and 10 for such components. The excess material is removed by various machining operations, which are a major contributor to the cost of forged components. Machining distortions are a problem with most forged components which are quenched rapidly in order to generate the required mechanical properties.  Distortion can be caused by material bulk stresses resulting from heat-treating operations, or from local near-surface machining-induced stresses.  Typically additional machining operations and setups are added in a time-consuming and costly trial-and-error approach to minimize the effects of part distortion. Manufacturing residual stresses can adversely impact the behavior of the components during service. There is a need to understand the effects of heat treating and machining on distortion and to predict, minimize, and control these distortion-related processes.  The objective of this project is to establish a modeling method that accurately predicts distortion during machining of 3-D shaped forgings used in aircraft engines and airframe structures.  Prediction and validation of machining distortions during broaching and milling operations due to bulk residual stresses will be presented.  Future work will involve generation of experimental data under controlled and under production conditions and extensive model validation followed by implementation on production hardware. This program is funded by the USAF Metals Affordability Initiative (MAI).