Hypersonic flows are a field of great interest since the sixties of last century because they occur in the planetary entry of space probes and they have recently attracted renovated attention due to development of hypersonic cruise missiles. Currently, the dominating method of study for high Mach number flows is Computational Fluid Dynamics (CFD), which have become sufficiently powerful, and have replaced the old analytic methods. In the present work, a computational model has been developed for simulating flows of a multicomponent air mixture around a hypersonic cruise missile (HCM) using the commercial CFD software STAR-CCM+. The investigations aim at verifying, first of all, the effective occurrence of chemical reactions of an air mixture of eleven species (N, N2, O, O2, NO, N+, O+, N2+, O2+, NO+, e-), then to evaluate the possible presence of the ionized particles species and finally to assess whether their amount is high enough to generate an appreciable electric field or not.