The fundamental performance of a linear Faraday type magnetohydrodynamic (MHD) accelerator under chemical and thermal equilibrium conditions is studied in this paper. Quasi-one dimensional numerical simulation is performed to characterize acceleration along the specified channel. In order to solve the set of differential equations of magnetohydrodynamics, the MacCormack scheme is employed. In this present calculation, a working gas of air-plasma, consisting of diatomic molecules of nitrogen, oxygen and hydrogen, is considered in order to actualize application of the MHD accelerator propulsion system. Numerical results show the characteristics of flow velocity, gas temperature and electrical conductivity of the MHD accelerator with the working gas of air-plasma. The computations are compared with numerical simulation results using the inert gas of argon evaluated in past studies. (c) 2005 Elsevier Ltd. All rights reserved.