The PARSEC CEE is the primary achievement of several years of effort at NASA's Marshall Space Flight Center. The CEE was developed to allow engineers in the Advanced Concepts Department to rapidly prototype launch vehicle and spacecraft concepts.
QCAD is an application for computer aided drafting (CAD) in two dimensions (2D). With QCAD you can create technical drawings such as plans for buildings, interiors, mechanical parts or schematics and diagrams. QCAD works on Windows, Mac OS X and many Linux and Unix Systems.