A computational study has been performed on hypersonic high-enthalpy viscous air flow past blunt bodies. In the thermochemical processes describing this nonequilibrium flow, nonpreferential or preferential vibrationdissociation-vibration coupling and vibration-vibration energy exchanges have been taken into account. A fivespecies reactive air mixture, in which the diatomic species NI and C>2 are in thermal nonequilibrium, was considered. The set of equations was solved using a second-order implicit finite difference scheme. Several flow conditions, corresponding to a range of Mach numbers from 14 to 18, in connection with available experiments were investigated. The predicted shock standoff distance and stagnation heat flux are in agreement with the experimental data. These conditions were used by several authors to validate theirs computations. Through a code-to-code comparison, the effects of the physical modeling, on the temperatures and the species mass fractions distributions, are emphasized.