Three dimensional aerothermodynamic analyses of flows around re-entry vehicles, such as HYFLEX (Hypersonic Flight Experiment), Space Shuttle, and HOPE (H-2 Orbiting Plane), have been carried out on the Numerical Wind Tunnel (NWT) of the National Aerospace Laboratory. The simulations have been performed with a domain-decomposition parallel-processing approach. Comparison of the results with data from flight measurements and/or numerical simulation by other programs has been made.