Dynamic load predictive model for aircraft taxiing excitation and landing impact

To accurately predict the dynamic load effect of the aircraft on the airport runway, full-scale virtual prototype models of seven representative civil aircraft types were developed using ADAMS/Aircraft. Multi-state ground movement simulations of the aircraft were conducted, including the taxiing excitation under different taxiing speeds and runway roughness conditions during the takeoff stage, and the landing impact under different sink rates and pitch angles during the landing stage. Dynamic load coefficients under different conditions were calculated, and the influence rules of multiple factors were revealed. A predictive model for the dynamic load coefficient was established through mechanical derivation and regression analysis. The sum of the mean value and three times the standard deviation of the dynamic load coefficient of taxiing excitation was taken as the upper limit value, and the most unfavorable conditions of taxiing excitation and landing impact were analyzed. Research results indicate that the dynamic load coefficient of aircraft taxiing excitation follows a normal distribution. The mean value decreases with the increase of taxiing speed, and the standard deviation increases with the increase of runway roughness and taxiing speed. The fitting accuracies of the predictive models for the mean value and standard deviation of the dynamic load coefficient are higher than 0.997 and 0.948, respectively. Under the most unfavorable condition, the sensitive speed and the maximum dynamic load coefficient of the aircraft increase with the aggravation of the deterioration degree of runway roughness. Under the combined action of lift and runway unevenness, the maximum dynamic load during aircraft taxiing is greater than the static load. The peak value of the dynamic load coefficient of aircraft landing impact significantly increases with the increase of sink rate and slightly decreases with the increase of pitch angle. The fitting accuracy of the predictive model for the peak value of the dynamic load coefficient of landing impact is higher than 0.971. Because the maximum landing weight of the aircraft is less than the maximum takeoff weight, the maximum impact dynamic load during normal landing is less than the maximum dynamic load during takeoff taxiing. However, when the aircraft approaches the limit sink rate, the maximum impact dynamic load is higher than the maximum dynamic load of taxiing. Thus, it is necessary to consider them simultaneously when analyzing the most unfavorable condition. The established predictive model for aircraft dynamic loads can provide more reasonable load parameters for runway design and analysis.