East-West Line disruption: Investigations underway, LTA to appoint expert advisory panel to review findings

SINGAPORE: The Land Transport Authority (LTA) has begun a probe into the six-day disruption of train services on the East-West Line between Jurong East and Buona Vista stations.

The investigations are expected to be completed in a few months, said LTA on Wednesday (Oct 2), a day after train services resumed.

The findings, to be made public, will be reviewed by a panel made up of six experts.

Investigations will be conducted across several areas.

"First, we will investigate the root cause of the axle box failure. LTA’s investigations will include a forensic study into the nature of the axle box failure, and identify any other potential contributory factors that led to the incident," said the authority.

It will also look into the procedures involving fault detection and incident handling, and determine if appropriate actions were taken.

Finally, LTA will review the service recovery and disruption mitigation effort, to "ascertain the timeliness and comprehensiveness of the responses taken" by train operator SMRT. 

The Transport Safety Investigation Bureau (TSIB) will also carry out an independent safety investigation on the disruption, said the Ministry of Transport.

To support its investigations, LTA will appoint an Expert Advisory Panel (EAP) to review the findings and advise on technical matters.

The panel will be chaired by Mr Malcolm Dobell, former head of train systems for London Underground, and comprises five other local and overseas experts:

• Dr Tony Lee and Mr Chen Chao, both of whom have extensive expertise in rail operations and maintenance;
• Mr Chew Tai Chong, who has expertise in rail system engineering and train design
• Professor Gan Hiong Yap, who has expertise in railway engineering
• Professor Manoj Gupta, an expert in material science with a background in mechanical engineering

The disruption began on the morning of Sep 25 after a faulty train caused a power trip and damage to the track and other equipment.

A defective component known as an axle box had dropped from the train onto the tracks, causing a bogie - or an undercarriage with wheels - to come off the running rail between Dover and Clementi stations.

This resulted in extensive damage to the tracks and other equipment. Engineers also found damage to power cables, the third rail that supplies power and three machines used to divert trains to different tracks.

Full restoration of services, initially planned for the following Monday, had to be pushed back by a day after new cracks appeared on repaired rail segments during stress tests.

The 12 new cracks came on top of the 34 that had first developed along a 1.6km stretch between Dover and Clementi MRT stations. 

For almost a week, MRT services were disrupted between nine stations from Boon Lay to Queenstown, with the stretch between Jurong East and Buona Vista the most severely affected.