The systems, which will automatically apply brakes and bring trams to a halt if they exceed speed limits in certain locations, will be installed across the capital’s network in a UK first.
The installation follows the derailment of a Tramlink service in Sandilands, Croydon, on 9 November 2016. The tram overturned on a sharp bend after travelling at an estimated 73km/h in a 20km/h zone, killing seven people and injuring 62 others.
An investigation by the Rail Accident Investigation Branch (RAIB) found driver error was the cause of the accident, with the most likely scenario being the driver having a ‘microsleep’ episode before reaching the bend. It also found other previous incidents of speeding on the section of track.
Transport for London (TfL) said Engineering Support Group will build and install the systems by the end of 2019. The automatic braking will work alongside the driver protection devices that have been used since September 2017, alerting to any signs of driver distraction or fatigue. Other recommendations from the RAIB, which have mostly been completed, include a permanent speed reduction across the network, speed monitoring and signs at ‘significant’ bends, and an enhanced customer complaints process.
“We will never forget the tragedy at Sandilands and from day one have focused our attention on preventing this type of incident from ever happening again,” said Mark Davis, TfL general manager of London trams.
“Awarding the contract for a new automatic braking system is a first for trams in the UK, and not only will it improve safety for customers in London but we hope it will lead the way for other tram operators across the country. We will work to have the new system, which will automatically apply the brakes if a tram is exceeding the speed limit, in full operation by the end of the year.”
The automatic braking will initially be set up to prioritise high-risk locations as suggested by the RAIB, but TfL said the system will have the flexibility to be introduced elsewhere on the network.
A new lighting system, which will operate independently of the tram's battery in an emergency, will be installed over the summer. A new, 75% thicker film will also be fitted to doors and windows to improve containment in the event of an accident.
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