LONGITUDINAL AIRCRAFT RESPONSE ANALYSIS BASED ON SYSTEM IDENTIFICATION TECHNIQUES
Joel Laguárdia Campos Reis1; Dimas Abreu Dutra1; Ricardo Luiz Utsch de Freitas Pinto1
1 Universidade Federal de Minas Gerais
Resumo
The dynamic response of an aircraft in its longitudinal plane has two very distinctive modes: short-period and phugoid. The short-period has natural frequency and damping coefficient values which relates it to typical maneuvers in a normal operation. Thus, it is important its determination by flight tests to verify the aircraft flight quality. Generally, these flight tests are carried out through traditional methods. However, such procedures can be improved both for how the aircraft is excited as for the method used for analyzing the acquired data. This paper propose a new methodology to analyze the short-period mode through flight test tech-niques, making use of a 3-2-1-1 maneuver. For data reduction, system identification techniques are used, which are based on the data acquired during flight and on the aircraft equations of motion. The system identification method used here has several statis-tical properties of a "good estimator", thus, the estimated values converge in probability to the true values. Therefore, it is under-stood that the analysis of the aircraft response by the proposed method has a greater precision to represent the characteristics of the dynamic stability mode.
Palavras-chave: Flight tests; System identification; Short-period; Aircraft Response; Output Error Method