2021 CP Derailment Caused by Undetected Rail Flaw

Courtesy of TSB

Winnipeg, MANITOBA – The TSB in Canada reported an undetected rail flaw led to a broken rail and subsequent derailment of a CP train back in October 2021.

The Transportation Safety Board of Canada (TSB) released an investigation report, R21S0048, regarding the 2021 Canadian Pacific derailment. Back on October 16, 2021, a CP train experienced an emergency brake application near Silton, Saskatchewan. The CP freight train was hauling 200 freight cars, 27 of which had derailed. TSB reports there were no injuries or dangerous goods involved.

The investigation determined “that the train derailed when the west rail broke as a result of pre-existing fatigue cracks that had spread down to the base of the rail in a sudden overstress as the train passed over it.” The investigation also showed that the frequency of rail flaw detection (RFD) testing along the Lanigan Subdivision exceeded regulatory requirements. TSB says that RFD testing accuracy is “limited by current technology” and because of these limitations, any rails with internal defects can be “misclassified as free of defects.” 

Nine months after the derailment, on July 29, 2022, CP implemented a Rail Integrity Non-Vital Overlay Detectors system. This sends automatic notifications to “CP’s Operations Centre in the event of a broken rail, rail gap, loose joint, or rail joint pull-apart.” These provide the Centre advance warnings so it can encounter “any such track discontinuities in non-signaled territory.”