Abstract
In this paper, we consider the stability analysis for a disturbed unsteady flow, which is two-dimensional incompressible flow in a symmetric film where the effect of viscosity can be neglected in comparison with inertia forces. The partial differential equations governing such flow are obtained from the Navier - Stokes equations and we obtain an analytic solution for those equations. The whole system is disturbed and we found the regions where the flow is stable or unstable.