The train captains and operations control centre staff involved in the Joo Koon collision were unaware that a train’s protective bubble can be deactivated, Transport Minister Khaw Boon Wan said in Parliament on Wednesday (Jan 10).
Authorities had said an abnormal condition on signalling equipment had disabled a feature designed to apply a protective bubble around the affected train.
“The operations control centre staff and the train captains did not know that the protective bubble could be deactivated,” Mr Khaw said.
“Had they been aware of this, the train captain on the second train could have switched from automatic to restricted manual mode to drive the train manually or, as a last resort, engaged the emergency stop button to keep the train from moving.”
Mr Khaw was responding to a question from Non-Constituency Member of Parliament Dennis Tan, who had asked whether personnel could have taken other measures to ensure the second train remained stationary.
The minister reiterated that the train captain was trained by signalling system supplier Thales, which shared the “assumption” that the protective bubble could not be deactivated.
“In hindsight, one can blame the captain, but I don’t,” Mr Khaw stressed. “Because he was mentally not prepared and never trained to react for that kind of scenario.”
If the train captain had switched to manual mode, Mr Khaw added, he would have had the “reaction time” to stop the train.
Mr Khaw compared the incident to a traffic accident his friend had got into. His friend, despite slowing down and checking when approaching a pedestrian crossing, collided with an e-scooter, he said. The e-scooter rider later died.
“As a layman, when you just don’t have reaction time, are you responsible, to what extent are you responsible?” Mr Khaw asked. “At that moment, are you able to respond in time?”
He noted that while 36m – the distance between the first and the second train in the Joo Koon incident – was “not short”, he pointed out that the second train was travelling at 18kmh.
“First, you have to switch from automatic to manual mode, then from manual mode you could have access to the emergency buttons,” Mr Khaw said, referring to what the driver could have done in that situation.
“Based on the logs and review by the experts, they felt that the train operator just could not react in time.”
When Mr Tan asked if the driver could have applied the emergency brakes in automatic mode without the need to switch to manual, Mr Khaw replied that he was not "perfectly sure".
"I think it would depend on the design," Mr Khaw said. "I'm not perfectly sure of my answer here, but I'll check."