An ‘Honest Mistake’ By People Also Contributed to Massive MRT Disruptions on 14 Oct

On 14 Oct, while you were reducing contact with members of the public by increasing contact with your sofa, our train system experienced a massive disruption.

Around 123,000 commuters on three lines were affected by the disruption which lasted 3 hours and 36 minutes. 

It was later revealed that a series of unfortunate occurrences led to the huge disruption, including human error.

An ‘Honest Mistake’ By People Also Contributed to Massive MRT Disruptions on 14 Oct

As your grandfather told you after accidentally dropping a bowling ball on your foot, everyone makes mistakes. 

Some mistakes are more consequential than others, of course.

Speaking in parliament, Transport Minister Ong Ye Kung said an “honest mistake” was one of the many factors which led to the huge MRT disruption.

So, what was this error?

The first fault wasn’t actually human error but a power cable fault.

At 6.58pm that day, there was a breakdown in the insulation of a power cable along the Tuas West Extension.

This wouldn’t usually be an issue, because a circuit breaker at the Tuas West Road station should have kicked in to isolate the power cable fault.

But the circuit breaker likely remembered it was 2020 and refused to work.

Image: LTA

As a result, a secondary protection mechanism tripped, cutting off power to some stations on the North-South and East-West lines.

Here’s where the “honest mistake” was made.

Tried to Draw Power From Substation Without Isolating Fault

In attempt to rectify the issue, an SMRT staff member then tried to draw power from a different substation that supplies power to the Circle Line.

This could have been a good move, except he didn’t isolate the initial cable fault. So, instead of helping, this move caused the Circle Line’s power system to trip as well.

According to SMRT CEO Neo Kian Hong, the employee had misread the graphics display and thought that the fault had already been isolated.

Both the staff member and a supervisor have been suspended from their duties, and will only be permitted to resume after undergoing retraining and recertification.

A “Major Lesson” For SMRT Employee

When asked about the team’s preparedness in such instances, Ong said while employees learn many different SOPs to cater to different scenarios, every disruption is different, and snap decisions usually have to be made during emergencies.

“I have not been in their shoes and cannot imagine the challenge they are facing. But under the pressure of time and circumstances, the personnel involved made an honest mistake,” the former Education Minister added.

“I have no doubt this has been a major lesson for them, they wish they had decided differently, and they have much learning to share with their colleagues so that such a mistake will not happen again.”

Incident Could Have Been Prevented

It was later revealed that four similar cable faults had been observed at different locations since service on the Tuas West Extension started in 2017.

Image: LTA

LTA actually brought this up to the systems supplier, Alstom, in Jan this year.

Alstom agreed to replace the upper of two layers of power cables at the Tuas West Extension, and replacement work was supposed to start in October.

But, it seems to have started too late.

Now, both the cables and trip coils will be replaced, with the cost borne by Alstom.

Another breakdown seems unlikely, but then again, this is 2020, and most things that have happened in 2020 seemed unlikely.