Airplane landing gear performance solutions with an electronic analog computer

Abstract

The typical airplane landing gear is basically a rather simple shock absorbing device whose characteristics can normally be described with considerable accuracy by a system of three or four simultaneous differential equations. However, due to the fact that the system includes a number of non-linear and discontinuous elements, it has been impractical to obtain analytical solutions of the equations without making simplifying assumptions which severely limited the value of the results. For this reason the shock strut energy absorbing characteristics have generally been developed experimentally by laboratory drop tests of an actual landing gear, and the landing gear evaluation has been accomplished by extensive laboratory and flight tests. This design method is obviously far from ideal, since all structure effected by landing loads must originally be designed to assumed landing gear characteristics, and the landing gear test results do not become available in time to allow design changes to be made economically.