Research On The Evaluation Index Of Fixed Wing Aircraft Flight Quality

The concept of the flight quality of airc raft marks a great progress in im proving the operation of the aircraft.Safety,efficiency and economy are the basic pr inciples of flight operation,and flight safety is directly relate d to the quality of aircraft flying.So the requirements of flight quality specifications are correspondingly born.Th e flight quality of the aircraft is inherent in the aircraft,therefore,the aircraft must be designed and verified in accordance with the requirements of flight quality.For the modern advanced aircraft,a variety of complex control systems have been adopted to it in o rder to improve its maneuverability,this causes the plane's motion equation to be up to dozens of orders.According to the current flight quality standards,the equation of advanc ed aircraft must be evaluated first,and then it can be transformed into a certain form of low order system.Then,the flight quality of the aircraft can be evaluated according to the fitti ng result of the high order system and the low order system in a certain fre quency or time range.The system identification technology and the equivalent system method are widely used because of their convenience and efficiency.In evaluating the flight quality of aircraft,the m ain content of the equivalent syste m method is to m atch the unknown para meters in the low-order m odel.This paper first introduces the research status about flying qu ality specification and the basic knowledge,then starting from the low order model of specification provides,introduced the application in equivalent system matching with least square method and the maximum likelihood method.Getting the related parameters in the low order system through the high order system by these two kinds of algorithm s,justify the results by analyzing the response characteristics of high and low order systems,and then op timize them.Finally,some evaluation indexes of flight quality are used to evaluate the flight quality of the aircraft and discuss how to m ake a more scientific evaluation of the flight quality through the comparative analysis.