The problem considered here is that of predicting the non-linear behavior of delta wings at moderately high angles of attack and low speeds. In this operating regime, vortex lift and vortex bursting are important in determining the aerodynamic forces on the wing. The analysis begins with a vortex-lattice model to determine the circulatory lift and the leading-edge suction force. The vortex lift is then calculated from the suction force assuming that the leading edge vortices have not burst. The circulatory and vortex lift are then corrected for vortex bursting and flow separation using a semi-empirical approach to estimate the burst locations of the leading edge vortices.