DYNAMICS ANALYSIS OF THE MAIN LANDING GEAR IN 3D MODEL

Properly adjusted characteristics enable minimisation of loads that occur in the landing-gear components at the moment of touchdown. Therefore, dynamic analyses of the landing gear are conducted to provide capabilities to forecast their behaviour under hazardous conditions. This kind of investigation with numerical methods applied is much easier and less expensive than stand tests. However, the development of the landing gear FEM models is necessary. Methodology of the main landing gear numerical models developing and procedures of parameters selection for the real structure features representation is discussed in the paper. The nonlinear physical material properties were precisely defined. To describe material properties of all mechanical components of the landing gear, a materials chart describing parameters for the elastic range was used. In FEM model the following matters were taken into consideration: contact problems between collaborating elements, the phenomena of energy absorption by gas-liquid damper placed in the landing gear and the response of the landing gear during touchdown of a flexible wheel with the ground. Chosen results of the numerical analysis for the maximum load of the gear considered, corresponding to an aircraft’s 3-point landing at maximum decline speed allowed have been compared to experimental research’s results. The analysis presented in this paper is the first part of wider considerations concerning numerical assessment of landing gear life.