An identification-based approach for aircraft engine modeling using the nonlinear Hammerstein-Wiener representation was proposed. Hammerstein-Wiener modeling for both limited flight envelope and extended flight envelope was investigated. Simulation shows that the resulting model can be valid over 10% variation of rotational speed of the engine

compared with those linear models that are only valid over 3%—5% change of rotational speed. It is further demonstrated that the proposed method can be utilized over large envelope up to 20% variation of rotational speed of the engine. The fundamental idea is to use nonlinear models to extend the feasible/valid region rather than those linear models. This may consequently simplify the switching logic in the onboard digital control units. This is often overlooked in aircraft engine control community

but has been emphasized in the research.