Safety levels on the service have been under intense scrutiny since a crash in November 2016 when seven passengers died and a further 62 people were injured in a derailment.
It has now been revealed there were three serious incidents on the south London tram system in the space of two-and-a-half months last year, sparking probes into what went wrong.
Two trams were accidentally set on collision course on August 5, a driver went through a stop at 25mph in Mitcham the following month, and a slow-speed derailment happened in Addiscombe on October 21.
Details of the incidents have emerged for the first time in a report to a Transport for London safety panel. TfL commissioner Andy Byford said: “While none of these instances resulted in injury or harm to our staff or customers, they are being taken very seriously.”
The report shows a collision was averted between two trams after they were put on to the same line in opposite directions just after 1pm on August 5.
“The trams were stopped by each driver about 100 metres apart using a normal service brake when they became aware of the conflicting movement in the single line section,” it said.
The incident, which happened between King Henry’s Drive and New Addington stations, was blamed on a “background signalling loop failure”, where one driver was given the green light to proceed by an automated signal and the other was told to proceed by the control room.
An investigation which concluded in December produced 12 safety recommendations, including a review of the way controllers authorise trams to proceed. In the second incident, on September 14, a tram went through the Mitcham stop at speed and ran through a red signal before eventually being halted by the driver.
The incident was blamed on the driver being “distracted”, with a probe raising concerns that the tram’s automated safety system “did not detect possible inactivity, or lack of concentration, from the driver”.
The final incident happened on October 21, after a tram driver was given distressing personal news over the radio in the middle of a shift. “The tram driver believed that they were fit to drive and while they followed the instructions, the driver failed to check when setting the points at the emergency crossover for the return journey. This resulted in a slow speed derailment of the empty tram.”
FirstGroup, which shares responsibility for safety on the service with Tram Operations Limited and Transport for London, said today: “We have been working closely with TfL and the rail regulator on learnings from the three incidents last year, and recommendations
arising from these incidents are being fully implemented.
“These incidents should be seen in the context of a sustained period of improved performance, including some of our best safety figures on record in 2019/20.
“Safety is a core value for FirstGroup and our commitment to the safety of our passengers, our employees and others who engage with us is unwavering.”
The incidents have been investigated and reported to the Office of Rail and Road, but TfL expressed concern that Tram Operations Limited, which runs the service, did not reveal the full extent of the Mitcham incident until two months after it happened.
Details of the incidents have also been disclosed by TfL to legal teams in the Croydon tram crash inquest, due to go ahead on May 17. The driver Alfred Dorris was diagnosed with post-traumatic stress disorder in the wake of the crash.