Structure Optimization And Impact Resistance Research On Landing Gear Door

With the improvement of the aircraft’s flight speed, larger aerodynamic load is applied on thelanding gear door, which would result a larger deformation of the door. Because of the demand foropening and closing, the stiffness of the door should be higher. In order to increase the aircraftpayload, the weight of aircraft structure should be reduced as much as possible. The compositematerial is the best choice in aircraft structure due to its high specific stiffness and specific strengthIn this paper, aircraft landing gear door structure was researched, several structural patterns wereselected for the door: composite honeycomb sandwich structure、Z-type composite stiffened plate、I-type composite stiffened plate and T-type composite stiffened plate. Aiming at the minimumstructure weight, the structural parameters of different patterns were optimized with the constraint ofthe structure strength, the structure stability and stiffness. Finally the honeycomb sandwich waschosen for the landing gear door structure by comparing the weight characteristics of differentstructural patterns.The landing gear doors are located at the bottom of fuselage, it would easily suffer foreign objectimpact which would cause damage and reduce the bearing capacity of structure. Based on elementfailure and material stiffness degeneration, the low impact finite element model of the compositehoneycomb sandwich structure was established in software ANSYS/LS-DYNA. Damage of sandwichstructure at different time was obtained, and the influence of impact energy、honeycomb thickness andsequence on the impact damage was analyzed.