This paper introduces an innovative approach to aerodynamic parameter estimation for nonlinear aircraft models, specifically addressing the limitations inherent in traditional methods, such as overfitting and ill-conditioning. Expanding upon the methodology developed in previous research, this study proposes a sparsity-enhanced technique designed to robustly approximate nonlinear aerodynamic coefficients. The efficacy of the proposed method is demonstrated through its application to high-fidelity nonlinear simulations of F-16 and X-31 aircraft models, using data derived from established aerodynamic parameters. A comparative analysis reveals that the proposed approach provides more accurate estimates of unknown coefficients, underscoring its potential to advance aerodynamic modeling and control system design in complex flight regimes.