News release

Defective brake components and faulty wheel sets must be identified in a timely manner

Gatineau, Quebec, 10 April 2013 — Defective air brake components were a central cause of a main track derailment approximately 13 kilometers west of Golden, British Columbia, in December 2011. That is one of the findings in the Transportation Safety Board of Canada (TSB) investigation report (R11V0257) released today.

On 27 December 2011, a Canadian Pacific freight train was travelling from Lethbridge, Alberta, to Vancouver, British Colombia. While proceeding westward, the train's emergency brakes were activated automatically and 32 hopper cars derailed. No one was hurt and no dangerous goods were released.

The investigation focused on broken brake and wheel components on a hopper car, finding that brake components had failed due to a pre-existing fatigue crack due to a casting surface irregularity. The fatigue cracking had likely been caused by abnormal stresses resulting from the interaction between the brake components and wheels that were not perfectly round on one of the car wheel sets.

The investigation concluded that if significant wheel defects are not identified and the affected wheels removed from service in a timely manner, there is an increased risk that the defective wheel will compromise the integrity of other car components, resulting in their failure.


The TSB is an independent agency that investigates marine, pipeline, railway and aviation transportation occurrences. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.

For more information, contact:
Transportation Safety Board of Canada
Media Relations
Telephone: 819-994-8053
Email: media@tsb.gc.ca