That “deceptive” traffic light and the train collision involving hundreds of passengers

London, 5 October 1999. Two trains loaded with commuters collided head-on, killing 31 passengers and injuring 417, making history as one of the worst rail accidents in Britain, after the one that occurred …

That "deceptive" traffic light and the train collision involving hundreds of passengers


London, 5 October 1999. Two trains loaded with commuters collided head-on, killing 31 passengers and injuring 417, making history as one of the worst rail accidents in Britain, after the one that occurred a few kilometres away, in Southall, two years earlier. The collision, which occurred near Paddington station, is known as the 1999 rail crash. Ladbroke Grove.

The causes of the clash

On 5 October 1999, at 8.06am, a Thames Trains train left the busy London Paddington station, bound for Bedwyn station in Wiltshire, with 147 passengers on board. The railway line between Paddington and Ladbroke Grove Junction is bi-directional, i.e. with a one-way trackwhich trains must travel along, stopping at stops, signalled by a series of traffic lights. This is a complex route, during which the driver must pay close attention every time he encounters a traffic light.

That morning, the Thames Trains train arriving at Portobello Junction, driven by 31-year-old Michael Hodder, failed to stop at the stop sign signalling the arrival of another train from the west, i.e. from the opposite direction, hitting it head-on. The train collided at a speed of around 210 km/h with a high-speed Intercity train of the Great Western Railway company, departing from Cheltenham and headed for London Paddington station. The violent impact between the two trains will cause the death of both drivers and 29 passengers, 23 of whom are passengers of the British Rail Class 165 of Thames Trains and 5 of whom are travelling on the high-speed train. In addition to the deaths, the collision causes 417 injuries, becoming one of the worst rail accidents in the history of Great Britain.

When firefighters and rescuers arrive at the scene of the disaster, they find the survivors immersed in a hell of fire and sheet metal. The more minor injuries, who fortunately escaped death, are in shock, and fires are raging all around. The Class 165 is structurally less solid than the Intercity, whose structure is around 400 tons, which will cause the destruction of an entire carriage of the Thames Trains vehicle and a violent explosion. But why didn’t Hodder stop at the stop signal? Thames Trains trains are equipped with a automatic alarm systemwhich warns the driver whenever the train passes a traffic light, whether it is yellow (the all-clear signal) or red. The driver, when he receives the stop signal, must confirm that he has received the alarm by pressing a button. But did Hodder do that that day?

The investigations and the responsibilities

Unfortunately, having lost his life, Hodder could not provide an explanation for that unusual gesture for an experienced engineer, which the investigators initially interpreted as a possible suicide. It was crucial to find the black box. Meanwhile, investigators discovered during the investigation that on the Sn109 signalwhere Hodder was supposed to stop, the 4 lights on the traffic light were not positioned in sequence, but in an L shape, making one of the lights less visible than the others. From the black box recovered from the wreckage, it was clear that Michael Hodder had responded to the alarm signal at point Sn109, but had decided to continue, deceived by the traffic light considered anomalousThe Healthy and Safety Executive, who were investigating the route taken by the Thames Trains train on 5 October, had another train take the same route as the Class 165 at the same time and found that at 8am the sun was low and behind the trains, making the L-shaped light at Sn109 either poorly visible or even a different colour.

Hodder, that morning, due to the reflection of the sun, may have mistaken the red signal for yellow and instead of stopping the train, accelerated. The young driver had therefore not deliberately led the passengers to certain death, but Network Rail, the company that had installed the semaphore at point Sn109, was instead fined for negligence. Finally, Thames Trains also paid for the disaster, for not having provided Michael Hodder with the correct training regarding the dangerous and misleading traffic light Sn109.

Following the Ladbroke Grove disaster, Network Rail replaced the L-shaped traffic lights and, to make Britain’s railway lines even safer, trains running on that route have now been fitted with an automatic stopping system.