Is it possible to perform a modal analysis (SOL103) and a static computation (SOL101) in a single run? The main goal is to recuperate the system matrices. Otherwise the mass and stiffnes matric are build twice.
You can run SOL 103 with a static and a modal subcase. This is typically done for a pre-stressed modes analysis where the differential stiffness due to the static loading is included in the normal modes calculation. However, if the STATSUB case control in the normal modes case does not reference the static subcase, the modes will be unaffected and the static subcase and normal modes subcase results will be independent.