Editor’s Note: This blog is the second part of a two-part series. View Part 1.
On October 22, 1895, the Granville–Paris Express derailed and crashed through Montparnasse Station. Several passengers and crew members were injured, and a pedestrian was killed by masonry that fell as the train crashed through the station’s façade.
In last week’s blog, we examined the incident’s impact on the public safety of those in and around the station. Starting with one unmet goal is a simple way to define a problem and begin the analysis, but incidents often impact two or more goals. Here we’ll show how multiple goals can be captured in a problem definition and Cause Map™ diagram as we dig into the causes of the Montparnasse derailment’s impact on three additional goals: property, schedule, and the safety of those onboard.
In case you missed it, check out part one: Unraveling One of History’s Most Infamous Wrecks: The Montparnasse Derailment.
When the Granville–Paris Express pummeled through Montparnasse Station, five people were injured including two passengers, a fireman, and two conductors. Why were these people injured? Because of the blunt force impact on passengers and crews. Why did the passengers and crew experience blunt force impact? Because the train broke through the buffer stop, the platform, and the wall of the station. Why did the train break through the buffer stop, platform, and station wall? Because it was unable to stop. Why was the train unable to stop?
If you read last week’s blog, you know that we already answered this question when we analyzed the incident’s impact on public safety. We previously identified the malfunctioning Westinghouse brake as a cause of the train being unable to stop. However, that’s not the only cause. There was also not enough time to apply the brake, because the train was approaching the station too fast.
Onboard Safety 5-Why Cause Map™
There are multiple places that we can go from here. We can ask ourselves, “Why was the train going too fast?” But the answer to that question is likely to emerge when we look at the next unmet goal: impact to schedule.
Another consequence of the Montparnasse derailment was the delay in train operations. Why were train operations delayed? Because the Granville–Paris Express damaged the platform station and tracks. Why did the damage occur? Because the train was unable to stop.
Why was the train unable to stop? We’ve answered this question two different ways in our previous Cause Map™ diagrams. We already know that the Westinghouse brake failed and that the train was pulling into the station too fast. But if you recall our description of the incident from last week, you’ll remember that the conductor grabbed the emergency manual handbrake too late because he was distracted with paperwork. That’s also a cause of the train’s inability to stop.
Schedule Delay 5-Why Cause Map™
We’ve saved the most eye-popping impact for last. As anyone can see from the pictures, the Montparnasse derailment created significant property damage. Why was there property damage? Because the façade of the train station has a huge hole in it (not to mention the damage to the rails, the bumper, the sidewalk, and the train itself).
Why does the façade have a huge hole in it? Because the train broke through the front wall of the station. Why did the train break through the front wall of the station? Because it traveled 98 feet across the concourse inside the station. Why did the train fly across the concourse? Because it broke through the buffer stop and onto the platform. And why did it break through the buffer stop? Because it was unable to stop.
Why was the train unable to stop? We now know there are multiple answers to this question. We’ll select the malfunctioning break to complete the 5-Why for impact to property.
Property Damage 6-Why Cause Map™
The Montparnasse derailment impacted four goals—public safety, the safety of those on board, schedule, and property—and we’ve created Cause Map diagrams for each. Now, we can bring them all together in a 25-Why that traces the impact to all four goals.
Back in the 19th century, the remediation of the incident focused on blame more than prevention. The driver of the Granville–Paris Express was sentenced to two months in prison and fined 50 francs, while the conductor in charge of the handbrake was fined 25 francs. While these actions are understandable, they did little to prevent similar incidents.
Fortunately, the industry has since developed a suite of solutions to prevent derailments, such as applying detonators along the track to warn engineers that they should brake in order to avoid a collision with a stalled out train on the tracks. There are also more robust communication systems aboard the train for faster, more efficient communication between the engineer and the conductor. Current rail traffic management systems employ sophisticated technologies to help prevent signaling and switching issues for railway and mass transit trains. Safety standards and inspections have become more stringent in order to lower the risk of malfunctioning equipment.
Great solutions like these come from digging into the details of incidents. If you play the blame game or focus only on the biggest red flags, you’ll miss them. To learn how to analyze the multiple causes of incidents—and identify multiple solutions to reduce the risk of future incidents—join one of our upcoming public workshops.
Editor’s Note: This blog is the second part of a two-part series. View Part 1.