Abstract: In this paper, the power spectral density technique is applied to study the taxiing-in-duced dynamic response in the aircraft due to runway uneveness, when the aircraft is taken as a two-freedom system. The mathematical expression of the statistical values of dynamic response are derived (including the mean square acceleration at the mass center σzi/g2; the mean square oleo deflection from static equilibrium position σ s2; and the mean square interaction force between tyre and ground σFt/w2). The non-linearities of air-spring and orifice damping of oleo-pneumatic undercarriage are also considered in the model. The results calculation of some aircrafts are in approximat agreement with ones of the references in which the deterministic method is used. Finally, As for a case of convensional oleo-pneumatic undercarriage, the above solutions are used to analyze the influence on the dynamic response in the aircraft during taxiing, of the main parameters of landing gear system. (including oleo air charging pressure pao; the initial volume of air in shock absorber vo; and the pure orifice area at static equilibrium position Ao). The results in this paper may by used as references in landing gear design.

Key words: landing gear, dynamic response, power spectrum