Points glitch caused tram derailment
DRIVER AND PASSENGER HURT WHEN IT HIT POLE IN BULWELL
A NOTTINGHAM tram driver and a passenger were injured after it derailed and crashed into a pole, closing the line for more than a week.
At around 5.06pm on June 12 last year a tram travelling southbound at around 25mph derailed at a split in the tracks that was in an unsafe condition at the north end of Bulwell tram stop in Nottingham.
A report by the Rail Accident Investigation Branch (RAIB), published yesterday, said the derailment was caused by the first and second bogies of the tram being routed in different directions as it passed over the diverging tracks.
During the derailment, the tram struck a pole that supported overhead line equipment causing a pane of glass to dislodge and hit a passenger, resulting in minor injuries.
The driver of the tram also suffered a minor injury, the report said. Significant damage was caused to the tram and infrastructure, with the line closed for extensive repairs until June 23.
Investigators said that a set of springloaded points were in an unsafe position because they had not reset correctly after two northbound trams travelled over them. “This can sometimes happen in normal working conditions, but the risk of this happening at the time of the accident had possibly been increased due to the environmental conditions causing the slide plates to be dry or contaminated,” the RAIB said.
The report said that a visual indicator located alongside the points, which warned they were not in the correct position, was not observed by the tram’s driver. The driver believed they would be informed if there were any issues with points but had not been so on this occasion.
RAIB’S investigation found Nottingham Trams Limited did not have an effective policy in place to inform drivers of points failures and had not specifically assessed the risk of a driver incorrectly passing a lineside indicator.
RAIB also said that the process Nottingham Trams used when introducing a new system to the tram fleet had not considered the effect the change may have on its drivers.
RAIB made three recommendations to Nottingham Trams Limited, with the first being a review of control room policy and procedures to ensure that clear and practical guidance is available to manage the response to engineering faults. The second recommendation relates to the improvement of risk assessments.
The third recommendation concerns the consideration of human factors when assessing the effects of a proposed engineering change.
RAIB also identified a learning point to remind tram drivers to not make assumptions about the status of signals or indicators based on their previous experience.