Whether you’re a history buff, a train enthusiast, or an engineer that’s fascinated by bizarre accidents, chances are that you've seen the famous photograph of the Granville-Paris Express train hanging out of the façade of the Montparnasse train station. No matter how you discovered this image, it’s one that makes you wonder, “How the heck did this happen?”
If you guessed that a lot had to go wrong for a 50-ton train to crash through a station, you’d be correct. That’s why we’ll be analyzing this notorious incident in a two-part series. In part one, we’ll discuss what happened and dig into the causes of the incident’s impact on public safety.
All aboard!
On October 22, 1895, the Granville–Paris Express was running behind schedule. Engineer Guillaume-Marie Pellerin decided to stoke the coals and approach the station at cruising speed. Pellerin trusted that the Westinghouse air brake could stop the train on time, but the brake was ineffective. It’s unclear whether the brake itself was faulty, but any brake can be blamed as “failed” if it’s not used early enough when the speed is too high.
The train had a backup emergency brake, but the conductor in charge of applying that brake was distracted with overdue paperwork. As a result, the conductor slammed on the emergency brake too late. That’s when the train broke through the buffer, skidded across the station, and pummeled through the façade.
Passengers and crew members were tossed around the cabin, leading to several injuries. And right in front of Montparnasse station was Marie-Augustine Aguilard, standing in for her husband, selling newspapers. As she stood there, waiting for her husband to return, she was crushed by a piece of masonry.
Whenever we’re investigating an incident, historic or contemporary, we always start by defining the problem in terms of the impacted goals. This sets the stage for a structured and objective examination of the incident’s causes. In the case of the Montparnasse derailment, four goals were impacted:
Now that we’ve defined the goals that were not met, we can begin building a Cause Map™ diagram to understand the cause-and-effect relationships behind the failure to meet each of these goals. We’ll start with the most tragic of the four impacted goals: keep the public safe.
When we ask ourselves “Why was the public safety goal not met,” the answer is simple: because there was a fatality. Why was there a fatality? Because a person, Marie-Augustine, was struck by falling masonry. Why was Marie-Augustine struck by falling masonry? Because masonry fell from the building.
Why did the masonry fall from the building? Because the front wall of the train station was severely damaged, breaking apart as it was struck by the train. Why was the front wall damaged by the train? Well, because the train was unable to stop. And why was the train unable to stop? There are multiple answers, but for now, let’s focus on one answer: because the Westinghouse brake malfunctioned. This initial analysis brings us to the 5-Why Cause Map™ diagram below.
5-Why Cause Map™
The 5-Why above is accurate, but we can add more detail and expand our analysis. There are two causes for the effect “Person struck by falling masonry.” One is the masonry that fell from the building, illustrated in the Cause Map diagram above. But for Marie-Augustine to be struck, she also had to be standing at the exact spot where the masonry fell. Why was she standing there?
As the story goes, Marie-Augustine was standing outside the station because she was selling newspapers, waiting for her husband to return. This information allows us to expand to the 7-Why below.
7-Why Cause Map™
You may be asking yourself, “Why is it important to include the person’s location?” Incorporating this detail in our analysis allows us to identify solutions to further reduce the risk of future fatalities. On construction projects, organizations often mitigate risk by identifying drop zones where travel is restricted when overhead work is being done. While the Montparnasse incident was highly unusual and unanticipated, we could reduce risk with a drop zone to prevent vendors from standing too close to the building.
When something goes catastrophically wrong, we naturally look for the biggest red flag. Once you spot the big red flag, it’s difficult to think about anything else. I bet you can’t stop thinking about that Westinghouse brake, right?
The Westinghouse brake is a great example of the kind of red flag you’ll see when you’re investigating incidents. It’s clearly unusual and undesirable, and it sticks out like a sore thumb. But if you overfocus on it to the exclusion of other details, you’ll miss opportunities to reduce risk. Once we expanded our analysis, we saw that we could significantly reduce the risk of future pedestrian fatalities even without solving the brake issue. With a barrier around the station, trains could crash through every day—but there would be no pedestrians in the area of potential impact.
Of course, this solution only applies to the Montparnasse derailment’s impact on public safety, and there is so much more to explore. Next week, we’ll dig into the incident’s impact on property, on-time arrival, and the safety of onboard passengers. Follow us on LinkedIn or subscribe to our newsletter to make sure you don’t miss it!
Editor’s Note: This blog is the first part of a two-part series. View Part 2.