Photo
A 2019 derailment in Alyth Yard - 2019 Photographer?
 External link
22 Car Derailment in Calgary's Alyth Yard Result of Coupler Knuckle Failure
9 July 2021

Gatineau Quebec - The Transportation Safety Board (TSB) of Canada's Investigation Report R19C0002 into a 2019 derailment in Calgary determined equipment failure caused 22 train cars to derail.
 
On the morning of 6 Jan 2019 fifty-six rail cars disconnected and ran uncontrolled down the emergency track and collided with stationary loaded hopper cars in the Canadian Pacific's Alyth Classification Yard in southeast Calgary.
 
The impact of the collision caused the derailment of 22 cars and a small amount of fertilizer pellets spilled.
 
No injuries were reported as a result of the crash.
 
The investigation into the derailment determined a knuckle, the jaw that allows two cars to securely connect when fastened with a locking pin, on one of the cars that was being switched failed while the cut of 75 cars was moving.
 
Fatigue cracking was located in the knuckle near the pin bore.
 
TSB investigators say the weakness was likely due to a manufacturing deficiency, but the crack was likely overlooked during the last detailed inspection, conducted two months prior.
 
The 2019 derailment prompted CP to install a fixed designated emergency track at the Alyth Yard for all switching operations, install retarders to slow cars during an emergency, increase the number of cars with air brakes, and introduce limits on tonnage during switching.
 
Ryan White.

*1. Appropriate news article image inserted.
      (because there was no image with original article)
*2. Original news article image replaced.
      (usually because it's been seen before)
News quoted by OKthePK website under
provisions in Section 29 of the Canadian
Copyright Modernization Act.