On Monday, 16 February 1998 at approximately 1630 hours, Train 924, a northbound Invercargill to Dunedin express freight was travelling at the maximum allowable line speed of 80 km/h when the locomotive engineer noticed a minor alignment ripple in the track ahead. The locomotive negotiated this area with only a slight lurch but 14 of the wagons in the body of the train became derailed as they traversed the misalignment. Similar occurrences could be prevented by reinforcing known procedures for identifying predictable high risk areas and destressing or applying appropriate speed restrictions. Two safety recommendations were made to the operator to effect these measures.
