Abstract: A steady-state transonic potential equation with large disturbance in the longitudinal direction is solved by using a type-dependent splitting scheme with variable parameters, in which different splitting schemes are adopted in supersonic or subsonic region. Selection rules for parameters are also discussed. Some numerical examples of transonic flows over NACA 0012 airfoil are presented. The results are compared with the available data. The results indicate that the present scheme is reliable and its convergence is comparatively fast.