某飞机串联多支柱起落架着陆撞击载荷飞行验证

Flight testing is the most authentic and effective ultimate means of aircraft design verification and qualification. The main landing gear of a large aircraft adopts an unusual combined multi-strut form, with complex force transmission and landing impact loads on the landing gear structure. The technical difficulty of flight verification is unprecedented. The structural characteristics of the landing gear combined multi-strut and the mutual collaborative bearing between the struts are analyzed. The load-measuring strain gauge bridge is designed. An integrated load calibration scheme including the calibration load conditions for simulation of the collaborative bearing relationship between the struts is designed. A new method for evaluating the linearity of strain bridge load response through partial correlation coefficient is developed to address the issue of multiple variables and large amounts of data in the analysis of strain bridge load response characteristics. A concept of load measurement model robustness is proposed, which takes into account the impact of calibration errors on measurement results and the mathematical evaluation indicator is derived. A new method for load measurement modeling is constructed based on the weighted averaging and ranking of response coefficients and partial correlation coefficients of strain bridges, taking into account both robustness and goodness of fit. The measured loads of a typical landing impact process of an aircraft measured by the model are provided, the loads change patterns are analyzed qualitatively, and the loads amplitude is evaluated quantitatively. The results show that the landing gear load calibration and modeling method is correct, which can be used as a reference for relevant engineers and technicians. The measured landing impact loads change patterns are clear and reasonable, and the measurement value is correct, which provides an important basis for identification and improvement of the aircraft design.