Abstract: The operational capacity and efficiency of a combustion turbine is increased by treating the turbine inlet air to increase its density. The inlet air treatment is achieved in a columnar tower with the inlet air being drawn in at the top of the tower. Treatment water is injected into the tower at a downward velocity greater than that of the inlet air to establish a vertically descending, two-phase co-current flow of inlet air and treatment water. The system utilizes the natural phenomenon of drag-induced pressure boost to the air achieved by the difference in the relative velocities of the inlet air and the treatment water in the co-current flow. By utilizing a cold treatment water, for example at 32.degree.-40.degree. F., the tower creates a direct contact heat transfer situation that cools the inlet air, thereby further increasing its density.