Performance Diagnosis for Turbojet Engines Based on Flight Data

Abstract

The purpose of the current study is to improve the flight data analysis in the existing program of flight operations quality assurance (FOQA) of the airlines. The goal is to detect any potential problems related to engine health. The exhaust gas temperature (EGT) is the primary parameter in performance monitoring and diagnosis. Performance reference models are obtained through fuzzy-logic modeling. As the first example in the present paper, the potential problems and abnormal conditions can be diagnosed after a comparative analysis with the reference model for a four-engine jet freighter. This paper also uses a twin-jet passenger transport as the second example to illustrate the concept of relative efficiency for engine components. The sensitivity derivatives of EGT with respect to the operational variables indicate that the performance of these two engines has been declining because of aging.