Dynamic Plate Thickness of ERA Sandwiches against Shaped Charge Jets

The equation for the dynamic plate thickness is derived as a function of standoff distance Z0, jet tip velocity vj0, cutoff velocity vjc, plate velocities vPI and NATO angle of the ERA sandwich. The dynamic thickness is presented as functions of the different parameters for the front plate – flying against the shaped charge jet – and the rear plate – flying with the shaped charge jet. But the dynamic thickness is only one of the reduction factors of ERA sandwiches.