Advanced Estimation for Aircraft Engines

This paper reviews recent industrial applications of estimation techniques to aircraft engines. Estimation is considered here in a broad sense. An estimator is any algorithm that processes engine measurements to compute engine signals, or parameters of interest, that are not directly measured. The paper begins with a summary of aircraft engines fundamentals, followed by brief descriptions of basic concepts in the areas of engine controls, engine fault detection and isolation, and engine health management. Practical estimation-based approaches in these areas are covered in some detail. These approaches include: control schemes that regulate estimated thrust, fault detection and classification algorithms based on estimator residuals, and health monitoring procedures that track deterioration of key engine model parameters. Several case studies, based on recent programs at GE Global Research and GE Aviation, are described in detail. These case studies contain validations of the proposed solutions via implementations using high-fidelity engine models. The paper concludes with a review of some open problems. This paper intends to be a starting point for researchers in academia and industry looking for an overview of estimation methods used in industrial jet engine applications.