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Rail transportation safety investigation R17Q0061

The TSB has completed this investigation. The report was published on 10 September 2018.

Table of contents

Uncontrolled movement of railway equipment

Train PH651
Mile 128.6, Wacouna Subdivision
Mai, Quebec

View final report

The occurrence

On , in order to carry out en-route switching operations, a Quebec North Shore and Labrador Railway consist of 159 cars loaded with iron ore had been left on the main track of the Wacouna Subdivision in Mai, Quebec. A few minutes after the locomotives were uncoupled from the consist, the cars began to roll uncontrolled and passed Signal 1286 in Mai. The relief locomotive engineer, who was located on the ground nearby, took action to stop the uncontrolled movement. There was no damage and no injuries.

Media materials

News releases


Undesired release of air brakes led to 2017 uncontrolled movement of rail cars north of Sept-Îles, Quebec
Read the news release

Investigation information

Map showing the location of the occurrence


Before joining the TSB in 2011, Manuel Kotchounian worked nearly 10 years at Transport Canada, where he held various positions including remedial measures specialist and means of containment specialist. Prior to that, Mr. Kotchounian worked at the National Energy Board as a senior pipeline engineer, providing technical expertise in public hearings, inquiries, and investigations related to pipelines and public safety, acquiring experience in regulatory affairs and technical matters pertaining to pipelines, pressure vessels, tank cars, and dangerous goods. Mr. Kotchounian holds a Bachelor of Engineering and a Master of Applied Sciences from l'École Polytechnique de Montréal, and is a registered professional engineer in Ontario.

  Download high-resolution photos from the TSB Flickr page.

Class of investigation

This is a class 3 investigation. These investigations analyze a small number of safety issues, and may result in recommendations. Class 3 investigations are generally completed within 450 days. For more information, see the Policy on Occurrence Classification.

TSB investigation process

There are 3 phases to a TSB investigation

  1. Field phase: a team of investigators examines the occurrence site and wreckage, interviews witnesses and collects pertinent information.
  2. Examination and analysis phase: the TSB reviews pertinent records, tests components of the wreckage in the lab, determines the sequence of events and identifies safety deficiencies. When safety deficiencies are suspected or confirmed, the TSB advises the appropriate authority without waiting until publication of the final report.
  3. Report phase: a confidential draft report is approved by the Board and sent to persons and corporations who are directly concerned by the report. They then have the opportunity to dispute or correct information they believe to be incorrect. The Board considers all representations before approving the final report, which is subsequently released to the public.

For more information, see our Investigation process page.

The TSB is an independent agency that investigates air, marine, pipeline, and rail 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.