Aiming at the demand of gust load spectra for transport aircraft,the work aims to establish a method for develop-ing the measured gust spectra for transport aircraft by 5×5 spectrum development method based on the measured load data and the task analysis method.Firstly,according to the task analysis method,the typical mission profile and mission section of the aircraft were determined,and the measured load data were pre-processed and analyzed statistically to obtain the distribution pa-rameters of the incremental normal acceleration exceedance number of the gust.Then,the curve of the average incremental normal acceleration cumulative exceedance number of the gust was obtained to develop the load spectrum of each mission sec-tion by the method of 5×5 spectrum,and then the mission profile spectra were developed and randomly ordered according to the proportion of the mission profile,so as to obtain the flight to flight spectra of the gust incremental normal acceleration.Fi-nally,an example was given to illustrate the method in detail.In the climbing phase of this type of transport aircraft,the gust load spectra were relatively more significant compared to those of other mission sections.The gust load spectra developed by this method can effectively reflect the characteristics of measured gust load data,demonstrating the rationality and feasibility of the approach.
transport aircraftmeasured spectrumload spectrum development methodgust normal accelerationnormal acceleration cumulative exceedance number curve5×5 spectrum