Simulation of sub- and supersonic flows in plasmatrons is considered. A physico-chemical model, numerical method and computation results for equilibrium inductive coupled plasma flows in a plasmatron are given. An effective preconditioning technique along with an implicit TVD scheme is used to solve the Navier-Stokes equations in both subsonic and supersonic regimes. The governing equations include source terms corresponding to the electromagnetic field influence: the Lorentz force components (so called, magnetic pressure) and Joule heat production. The necessary transport coefficients were calculated in advance for equilibrium air plasma as the functions of pressure and temperature. Transport properties were calculated by the precise formulae of the Chapman-Enskog method in temperature range 300 ≤ T ≤ 15000 K. Calculations of equilibrium air plasma flows for the IPG-4 (Institute for Problems in Mechanics, Moscow) discharge channel geometry with the channel radius Rc =0.04 m and length Zc =0.40 m were performed. Creation of both under-expanded and over-expanded jets exhausted from the plasmatron channel is considered. A comparison with different experimental results is given.