Aerodynamic Appraisal of the VEGA-C Launcher

In the framework of the VEGA Consolidation and Evolution Preparation Program, carried out by the European Space Agency to develop the VEGA-C launcher, several aerodynamic design activities have been performed with the help of both numerical and experimental campaigns. The results of those design efforts contributed to the definition of the launcher aerodynamic database, necessary to feed flight mechanics and vehicle performance characterizations. Launcher aerodynamic database is obtained by means of a buildup approach that exploits several contributions ranging from engineering judgments, flowfield numerical analyses, and wind tunnel tests. The final aerodynamic database has been also provided with suitable uncertainty models to assure reliable estimations of the launcher aerodynamic coefficients in the ranges of Mach, altitude, and attitude, expected for the vehicle along with the ascent flight. In this paper, the final aerodatabase and the whole building process are presented and discussed in detail. Finally, comparisons between wind tunnel data and results of flowfield simulations are also shown, together with extrapolation to flight judgments to accommodate for the Reynolds number effects. Result comparisons highlight that numerical and experimental data compare rather well, thus confirming the reliability of the present design efforts.