Autodesk Nastran In-CAD 2017 CAD-embedded finite element analysis software Autodesk® Nastran® In-CAD software, a general-purpose finite element analysis (FEA) tool for engineers and analysts, offers a range of simulation powered by the Autodesk Nastran solver. Features FEA software with CAD integration Autodesk® Nastran® In-CAD finite element analysis (FEA) software uses Autodesk Nastran solver and integrates with compatible software to simulate real-world behavior. Solve engineering challenges before you begin manufacturing.