The broken rod was replaced with a new rod and loading conditions were applied. Four strain gauges were attached at a distance of from the lower end, located 90 degrees apart around the circumference of the rod. Readings were taken during manual release and application of the brake and during emergency application of brake. The results showed that in addition to the expected direct tensile stresses at gauge positions there were substantial stresses due to bending when the brake was operated. The magnitude of stresses varied to such an extent that for the one farthest from the drum there was a change from tension to compression as the brake was released. The rod was not designed for such alternating bending loads. The rod was designed with a factor of safety 6.1 for tensile stress. But when alternative bending stress are induced, failure was inevitable.
