Many of the conclusions published in the book "Astronautical Engineering" are based on numerical results of the following software products:  SKYNAV          A computer program that helps solving trajectory optimization problems (Actual Price: 6999.-€).  1. Space Launcher Trajectory Optimization 2. Launch Vehicle System Analysis 3. Reentry Trajectory Simulation 4. Space Launcher Navigation 5. Planetary Mission Design  The example above shows the printout of a reference trajectory for a study of the European Ariane-5 launcher during the preliminary design phase. AEROCAD                                                                                                                   A tool for the preliminary aerodynamic design of aerospace vehicles: 1. Normal Force Coefficient and its Derivative 2. Pitching Moment Coefficient and its Derivative 3. Center of Pressure Location and its Static Margin The example above shows the printout of aerodynamic performance data for the feasibility study of a small airborne launcher derived  from Ariane-4 components.