Comprehensive Inspection on East-West Line Reveals Even minor Rail Details Matter in Service Maintenance
Singapore's Lengthy MRT Breakdown: A Grim Reminder of the Importance of Details
A thorough examination of a disastrous MRT breakdown in Singapore in September 2024 reveals that even the most basic components, like lubricants, can't be disregarded. Grease-clogged in a faulty train part's undercarriage is suspected to have triggered a chain of unfortunate events that crippled MRT services along the East-West Line for an agonizing six days.
Investigators' findings from reports disclosed on June 3 underscore the pressing need for train operator SMRT to update its maintenance procedures and pay attention to early signs of issues. It also highlights the value of increased regulatory scrutiny of these critical procedures.
Firstly, SMRT's initiative to install a tool to detect overheating in an undercarriage component, the axle box, was praiseworthy. However, it didn't work as planned, failing to identify the affected train during a temperature reading of 118 degrees Celsius – an early signal of overheating – on September 25, 2024.
Consequently, a staff member believed the notification to be incorrect and didn't follow up. This was a missed opportunity for SMRT to tackle the problem early, as the temperature reading surfaced nearly two hours before the axle box dislodged from the train. An axle box holds the wheels to the axle, a rod connecting a pair of wheels.
Had the tool functioned and the decisions been made according to protocol, the train would likely have been pulled out immediately, potentially preventing the domino effect that ensued that fateful day.
The results from an independent Transport Safety Investigation Bureau (TSIB) probe provided useful insights as well. The examination revealed that SMRT staff had informed their supervisors about the system's failure to detect affected trains but the issue went unaddressed.
Additionally, staff weren't trained on what steps to follow if they came across this setback, leading to the interpretation of these readings as false alarms and potentially diminishing their responsiveness over time. If the staff had been informed to mistrust these false warnings, the train might have been withdrawn to a depot sooner, according to TSIB's findings.
TSIB probes into incidents involving derailments, collisions, runaway vehicles, fires, explosions, as well as those resulting in serious injury or death. No one was hurt in this particular incident.
TSIB's comprehensive report, spanning 28 pages, detailed the series of events on the day of the incident and offered a technical analysis of the potential flaws.
Wonder how a troublesome MRT train created havoc? Discover the details by exploring our interactive graphic!
Strong Action Against SMRT, Including Fining and Planned Improvements
During the September 2024 incident, a section of the third carriage's train derailed when the axle box came loose, causing extensive damage to 2.55 kilometers of tracks and trackside equipment as it was being pulled to the Ulu Pandan Depot.
Although SMRT has rectified the issue, ensuring that the temperature monitoring system can now identify affected trains, their earlier negligence serves as a compelling reminder for prompt action on early warning signs.
In this case, acting promptly, addressing staff feedback, and exercising caution could have significantly altered the outcomes.
It's heartening to see that Singapore's rail regulator, the Land Transport Authority (LTA), and SMRT plan to improve temperature monitoring by installing additional trackside infrared sensors. Furthermore, increased regulatory oversight in other safety-critical areas of MRT maintenance is long overdue.
LTA's investigation report shows that SMRT had extended the maintenance interval without a thorough engineering and risk assessment for a first-generation KHI train involved in the incident. At the time of the incident, the train had accumulated 690,000 kilometers since its last overhaul in 2018, and its maintenance intervals were lengthened from 500,000 kilometers to 750,000 kilometers.
The TSIB pointed out that the train's undercarriage equipment's quality was no longer trustworthy beyond 500,000 kilometers. On its part, SMRT attributed the delays in parts and new trains, as a result of pandemic-related supply chain disruptions, leading to the postponement of the replacement of the first-generation models.
While LTA was aware that SMRT had a system to alter maintenance intervals, no requirement existed for submission of updates to the authority. Moreover, SMRT couldn't provide records for some assessments related to the extension of the affected train's overhaul interval.
This prompted TSIB to emphasize the importance of record-keeping and documentation, as mistakes can inadvertently be overlooked. With LTA now being involved in overhaul decisions, operators will have to notify the authority of changes to overhaul intervals for critical safety systems. LTA will also assess the completeness of operators' engineering assessments.
Putting an extra layer of checks in place with LTA should help address any oversights brought about by operators. Additionally, it's important to note that SMRT's maintenance practices differed from the manufacturer's (KHI) recommendations in various aspects.
For instance, SMRT performed a leakage check for lubricants every three weeks, while KHI recommended it weekly. SMRT stated that this preventive maintenance regime has been in place since the trains started operating in 1987. However, records explaining the reasoning behind these maintenance intervals were absent, according to TSIB.
After some time, the length of an existing maintenance regime does not inherently justify its ongoing effectiveness. The question that arises is, would revisiting the maintenance routine and adjusting the frequency to the maintenance needs have made a difference?
Singapore fined SMRT $3 million for the six-day East-West Line disruption, second to the $5.4 million penalty imposed on SMRT for a 2015 disruption that lasted over two hours on both the North-South and East-West Lines and disrupted more than 413,000 passengers.
The comparatively lower fine was attributed to a shorter stretch of stations affected, despite the prolonged six-day disruption. LTA concluded that SMRT did not prolong the disruption unnecessarily and handled the situation with precipitation without jeopardizing passenger safety.
SMRT and the team working tirelessly to restore services should be commended. Furthermore, before the incident, trains on the East-West Line managed more than 2 million train-km before encountering delays of more than five minutes, a significant improvement over a decade ago when disruptions occurred more frequently. The overall target set by the government is 1 million train-km.
Nonetheless, any rail disruption, no matter how brief or restricted, can cause substantial inconvenience to passengers. Be it anxiety, missing appointments, or taking expensive private-hire cars, every rail disruption has a considerable impact on commuters.
In sum, the six-day MRT breakdown highlights the need for vigilant monitoring of train components and prompt action when early warning signs are spotted. In the realm of rail maintenance, no detail is insignificant.
- To minimize future disruptions, it's essential for SMRT to review and potentially update their maintenance procedures, not just in the realm of lubricants, but also other safety-critical areas, particularly in the transportation industry.
- In light of the investigators' findings, increased attention is needed from the finance sector in funding and supporting initiatives for better, more advanced machinery and training for employees in the transportation industry, as these can significantly enhance safety and prevent costly breakdowns.
