Conversion from Powermill to Nastran is not supported yet :(

Powermill is a 3D Computer-aided manufacturing app developed by Autodesk Inc. It runs on Microsoft Windows and is used in many different engineering industries to determine optimal toolpaths to reduce time and manufacturing costs.

Powermill rapidly creates toolpaths on large, complex parts, works with surfaces, solids and STL meshes. It uses efficient roughing strategies and can create gouge and collision free toolpaths, which can be edited and optimized. The software obtains comprehensive range of finishing toolpaths, user-defined macros and templates for automated CAM, extensive library of tool types for use with 3- and 5-axis milling, and specialist tools for demanding industries and applications.

MSC Nastran is a multidisciplinary structural analysis application used by engineers to perform static, dynamic, and thermal analysis across the linear and nonlinear domains, complemented with automated structural optimization and award winning embedded fatigue analysis technologies, all enabled by high performance computing.

Engineers use MSC Nastran to ensure structural systems have the necessary strength, stiffness, and life to preclude failure (excess stresses, resonance, buckling, or detrimental deformations) that may compromise structural function and safety. MSC Nastran is also used to improve the economy and passenger comfort of structural designs.