Abstract: The overall objective with this paper is to evaluate a method for designing nonlinear controllers in aircrafts with concern in robustness against modeling insecurities and also to minimize the design effort. The later objective is of great importance since there exists, in the industry, an ambition to automatize the design for as far extend as possible. The nonlinear method, State Dependent Riccati Equation (SDRE), used in this work is a nonlinear version of classic LQ design and both are evaluated and compared for a few flying conditions. Also another nonlinear control method is tested. LQ and SDRE show equal performance during both looping and more complicated maneuvers, such as high angle of attack wind-vector roll. Further it is possible to automatize the LQ design as well as it is possible for SDRE. Still SDRE is preferable since it will always be somewhat more accurate than LQ. A Monte Carlo simulation is made on LQ and SDRE showing that the model is robust against relatively large modeling error of 40%.