CRAS is taking part to the ESA FLPP program contributing significantly to the computation of numerical simulations for to the aerothermodynamic database of the IXV vehicle. Numerical simulation of hypersonic flows represents surely a strong point for CRAS. Indeed, in this field CRAS boasts researchers with long experience and availability of state-of-art software tools. In addition to this, a new computing technique which promises significantly improvements in the simulation of flows with strong shocks is presently under development at CRAS. The paper is a brief overview of the numerical techniques presently, used in the contract activities related to the IXV program or under development at CRAS together with a selection of the most significant results.