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In this paper, a new model's critical speed predictions for five aircraft tires are compared with a shell finite element model's predictions (with and without centrifugal stiffening), a tread band model's predictions and experimental data. The model presented is a nonlinear, shearable and extensible viscoelastic ring on viscoelastic foundation subjected to an internal pretensioning force and the full complement of inertial forces due to its rotation. This model is referred to as the ring model for the remainder of this paper. Critical speed (linear) analysis of the model's non-linear equations of motion yields results which are in good agreement with experimental data. The model is quicker and less memory intensive than the shell finite element model while still maintaining the same degree of accuracy. It is also more accurate than the tread band model since it incorporates the effects of transverse shear deformation and the full complement of inertial forces.

Although aircraft tires are traditionally tested on external dynamometers, the effects of the curved test surface on normal contact pressure distribution and footprint area of a tire have not been previously addressed. Using the Tire Force Machine (TFM) at the Wright Laboratory Landing Gear Development Facility (LGDF), trends for pressure distribution and footprint area were investigated for concave, convex and flat plate surfaces. This evaluation was performed using the F-16 bias, F-16 radial and B-57 bias main landing gear tires at rated load and inflation pressures. The trends for overall tire footprint behavior indicate that the more convex the surface, the smaller the contact area and the larger the normal contact pressures. Conversely, the more concave the surface, the larger the contact area and the smaller the normal contact pressures. Based on these results, the study recommends a 168″ diameter concave (internal roadwheel) dynamometer for tire wear/durability tests.