News release

In its investigation report (R18V0016) released today, the Transportation Safety Board of Canada (TSB) found that a broken axle on a freight car led to the derailment of a Canadian National Railway (CN) train near New Hazelton, British Columbia.

On 19 January 2018, a CN freight train proceeding westward at 29 mph experienced a train-initiated emergency brake application near New Hazelton, British Columbia. A subsequent inspection determined that 27 gondola cars loaded with coal had derailed. Some of the product spilled into the nearby waterway. There were no injuries, and no dangerous goods were involved. The British Columbia Ministry of Environment and Climate Change Strategy monitored the site clean-up and recovery activities conducted by CN to ensure they met regulatory requirements.

The investigation found that the 52^nd car in the train had sustained a broken axle, leading to the derailment of the 27 cars. The axle broke as a result of fatigue cracking in the journal fillet radius, the area between where the wheel and wheel bearing is mounted on the axle. While the exact cause of the fatigue cracking could not be determined, fatigue cracks are known to result from abnormal cyclic loading due to a number of reasons, such as a wheel tread defect, a general out-of-roundness, or uneven loading from railcar truck components.

Axle fatigue cracks in the journal fillet radius are not detectable during routine safety inspections, as this part of the axle is concealed by wheel bearing components. Visual inspection is only possible during wheel and bearing replacement, or during axle reconditioning. Without alternate strategies to identify fatigue cracks or to predict the likelihood of fatigue cracks developing, problematic axles might not be removed from service in a timely manner, increasing the risk of broken-axle derailments.

See the investigation page for more information.