Why does railroads crash

The only information released about the potential cause of the incident is that after the first train derailed, it "knocked out all the signalling in the area". Graham Braithwaite, a professor of safety and accident investigation at Cranfield University, said that usually the "fail-safe" system in place across the network means that if signalling goes out - trains are told not to pass.

It means that if you cut power off to a signal, the default is that it goes to red. According to Network Rail: "If there's a power failure, the signal goes black and the driver knows not to pass a signal unless it has a green or yellow light; and if a point fails, the last signal before the set of points affected will automatically turn red so no trains pass.

But Professor Braithwaite added that "only works if there is a signal between you and the hazard", so the train may not have had anything to tell it to stop. And signals also tell train drivers what speed they should be doing, he says, so if the system failed, the second train would not have been told to slow down either. There was nothing visible on the line in the immediate aftermath of the crash, but speaking from the scene on Sunday night, Sky News correspondent Alex Rossi said nearby trees had been "blown over by strong autumnal winds".

But in light of further disruption over the weekend caused by flooding in Scotland, Professor Braithwaite said climate change "prevents a real challenge around extreme weather and railways". They have drones, helicopters and engineers doing track patrols - but it's a massive piece of infrastructure to manage.

Lisa Constable, climate and weather adaptation manager for Network Rail, did not comment on the Salisbury incident. But she said: "Ensuring the resilience of our network in the face of a changing climate is going to be one of our biggest challenges over the coming years.

Two independent groups of experts are currently looking at how to improve the situation, she added. Although accidents are extremely rare, problems with trains, tracks and the rail network have resulted in a small number of fatal train crashes in recent decades. If someone is found to have broken the law, they can be prosecuted by the police, while independent inquiries are set up to establish how the incident happened and what can be learned from it.

Investigations revealed the train derailed due to a set of faulty points, which should have been detected during a scheduled inspection five days earlier - but did not take place. On 10 May , a West Anglia Great Northern train from London King's Cross to King's Lynn passed over a set of points - moveable metal bars that allow trains to change from one track to another - at 96mph just south of Potter's Bar station in Hertfordshire.

The fourth carriage became detached, flipped into the air and crashed into a bridge and eventually into the station platform. The eighth carriage - the restaurant coach - overturned and hit an overhead power line, causing severe damage. It exposed widespread problems with privatised infrastructure company Railtrack, which was later replaced by Network Rail.

In Railtrack and contractor Balfour Beatty were found guilty of breaching health and safety laws related to maintenance. The Ladbroke Grove - or Paddington - train disaster is one of the worst in modern British history. It killed 31 people and injured when two trains crashed between the two stations in west London. Broken rails and welds were a factor in about 15 percent of derailments. Issues with track geometry were responsible for 7.

Track geometry includes train alignment, gauge, and elevation. Bearing failure was responsible for 5. Often broken tracks elude inspectors. In , a broken rail was linked to a fiery oil train derailment in southern West Virginia. Two inspections took place on the track prior to the accident.

Broken rails are putting the lives of railroad workers at risk. If you have been injured working on the railroad by a derailment or another type of accident, please call our FELA injury lawyers.

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