  New numerical models of line-driven stellar winds of late O stars are
presented. Statistical equilibrium (NLTE) equations of the most abundant
elements are solved. Properly obtained occupation numbers are used to calculate
consistent radiative force and radiative heating terms. Wind density, velocity
and temperature are calculated as a solution of model hydrodynamical equations.
Contrary to other published models we account for a multicomponent wind nature
and do not simplify the calculation of the radiative force (e.g. using force
multipliers). We discuss the convergence behaviour of our models. The ability
of our models to predict correct values of mass-loss rates and terminal
velocities of selected late O stars (mainly giants and supergiants) is
demonstrated. The systematic difference between predicted and observed terminal
velocities reported in the literature has been removed. Moreover, we found good
agreement between the theoretical wind momentum-luminosity relationship and the
observed one for Cyg OB2 supergiants.
