Dynamic Response of Airplanes in Ground Operation

This investigation deals with deterministic and stochastic analyses of dynamic response of airplanes to runway unevenness. After a brief review of various methods for runway unevenness representation, a new approach of power spectral representation of sectional ergodic runway is presented. This new method, while keeping the computational expedience of power spectral density techniques, has the important feature that the local uneven nature of runways can be revealed. Two complementary approaches are used to obtain dynamic response. They are time-history analysis and power spectral analysis. The mathematical idealization of airplanes used in analysis can take account of the nonlinear behavior of the landing gear systems and the flexural nature of the free-free airframe. The analysis of the dynamic response of the Boeing 707 airplane to a severely uneven runway is taken as an example solution in order to illustrate some applications of the methods. Finally, some of the more significant findings of this investigation are summarized.