Fatal train derailment: A closer look at what happened that tragic day

The deadly derailment of awestbound 112-car runawayfreight train that claimed the lives of three crew members Monday near Field, B.C., will be under investigation for some time.

Engineer AndrewDockrell, trainee DanielWaldenberger-Bulmer, and conductor DylanParadiswere killed when a Canadian Pacific Railway trainderailed on a curve near the Spiral Tunnels and plunged into the Kicking Horse River.

Here's what we know about the train and that section of track.

The Transportation Safety Board said the freight train, which had112 cars and three locomotives,had been parked with emergency brakes locked at the upper tunnelfor two hours when it started to move.

That set the train rolling down one of the steepest sections of railway in North America, one that involves sharp turns and two tunnels.

The Spiral Tunnels were built in 1909, replacing an even steeper line that took a direct route from the mountain pass to the valley floor. That old route, which was in place for 25 years,was twice as steep as the current route.

Derailments, however, continue. Nearly half of thosebetween Calgary and Field since 2004 took place within 30 kilometres of theSpiral Tunnels.

No onewas killed in any of those incidents.

The investigation into the crash on Feb. 4 is ongoing.

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