Wednesday, 18 April 2012

MRT breakdown COI: Day 1 - 16 Apr 2012

Inquiry throws spotlight on MRT maintenance
Lawyers' speeches for regulator and operator set scene for inquiry into train disruptions
By Christopher Tan, The Straits Times, 17 Apr 2012

WERE last December's massive train breakdowns a result of poor maintenance by train operator SMRT?

That was the key question posed at the high-powered Committee of Inquiry as it kicked off its proceedings at the Subordinate Courts yesterday.

The Land Transport Authority (LTA) fired the opening salvo, arguing that higher-than-usual vibrations were the main cause of the problem.

These were triggered primarily by flat spots on the metal wheels of the trains, which the operator is supposed to mill regularly, it added.

SMRT swiftly refuted the claims, insisting that it had kept to a stringent maintenance regime that was either equal to manufacturers' recommendations, or went beyond them.

Saying that the flat spots on train wheels were an issue faced by all train operators, it put the blame instead on 'ageing infrastructure' it had inherited from its predecessor MRTC.

'While SMRT cannot control issues like population growth which has increased the strain on the MRT system, SMRT has been actively working to mitigate this strain,' declared SMRT's lawyer Cavinder Bull. 'SMRT has not hesitated to spend money here.'

He noted that the twin phenomena of increased ridership and ageing infrastructure were 'important points of context which the committee should keep in mind'.

'It is in that context that SMRT has been trying its best to deal with challenges,' he said.

The disagreement between regulator and operator set the scene for what will be a six-week inquiry into train disruptions that affected more than 200,000 commuters over two days in December.


Since then, a team from the Criminal Investigation Department (CID) has spent 13 weeks gathering evidence.

Nearly 450 exhibits - either documentary or physical in nature - are expected to be presented to the committee.

A total of 108 witnesses have also been lined up, including three commuters who were affected by the disruptions.

'We have much to do in the coming weeks,' said Second Solicitor-General Lionel Yee, who was the first to speak in court yesterday.

But he also noted that the proceedings were not meant to be adversarial.

'Our focus must instead be on fact-finding and problem-solving,' he added.

'The MRT system is a vital piece of our public transport system and we owe it to the hundreds of thousands of commuters who rely on it every day to address these future-oriented issues.'

Mr Yee said that all the reports received by the committee so far seemed to rule out two possible causes.

The first was the use of heavier new-generation China-made trains.

The second was that the problem could be linked to the so-called floating slab track - constructed in tunnels underneath high-rise developments to insulate them from the noise and vibration of passing trains.

CID's assistant superintendent (ASP) Roy Lim also ruled out the possibility of sabotage.

Commissioned by Prime Minister Lee Hsien Loong himself after the breakdowns, this is the first Committee of Inquiry since the collapse of Nicoll Highway in 2004.

The three-member committee is chaired by Chief District Judge Tan Siong Thye and includes Professor Lim Mong King from the School of Mechanical and Aerospace Engineering at the Nanyang Technological University, and Mr Soh Wai Wah, director of prisons.

The judge wasted no time getting to the heart of the issue, posing a number of technical questions on Day One of the proceedings.

These included how many current collector shoes (which make contact with the third rail) a train can afford to lose before it loses power and whether the on-board back-up batteries were adequate in real-life conditions.

He even suggested that the fibre-glass opaque cover of the third-rail claw assembly could be transparent to make inspections easier.

In the December breakdowns, trains stuck in tunnels had limited lighting and ventilation, causing great discomfort.

At least one passenger fainted and another resorted to smashing open the window of one of the carriages using a fire extinguisher to let in fresh air.

The judge directed the inquiry to examine if there were more effective ways of managing disruptions.

He added that the high passenger capacity of trains meant bus bridging efforts will often be inadequate.

The proceedings continue today with ASP Lim's testimony, after which the committee will focus on events surrounding the first breakdown on Dec 15, starting with accounts from officers and station managers on duty that night.



SMRT: Flaws inherited from predecessors
'Ageing infrastructure and material defects key factors'

By Maria Almenoar, The Straits Times, 17 Apr 2012

AGEING infrastructure and material defects were significant factors in the December breakdowns, argued SMRT's lawyers in their opening address at the start of the Committee of Inquiry hearing yesterday.

And much of this was inherited from the train operator's predecessors, said senior counsel Cavinder Bull of Drew & Napier, who is representing the train operator.

Mr Bull took pains to outline in his 90-minute speech the history and structure of Singapore's train system.

He said the infrastructure for the North-South and East-West lines was set up in the 1980s by the Mass Rapid Transit Corporation (MRTC).

Today, this infrastructure is still owned by the Land Transport Authority (LTA), which took over MRTC's functions in 1995.

SMRT was granted a licence in 1987 to operate the MRT system.

Although it maintains the infrastructure, the train operator also inherited any inherent flaws in a system it had no hand in building, said Mr Bull.

The senior counsel proceeded to highlight two such flaws. The first was the ageing 'claws' that hold the third rail in place, allowing trains to draw their power as they brush against this rail.

While third-rail claws have gone through five generations of improvements since they were installed in Singapore, claws in the sites where train disruptions occurred on Dec 15 and 17 last year are still first- or second-generation types.

The court was told that Brecknell Willis, the British company hired to design and manufacture the third rail system for Phase 1 of the MRT system, had in 1987 suggested using a modified claw. This had a split pin locking system that ensured the claw could not jump out even under severe vibrations.

This modified claw is used in various MRT systems around the world and so far no failures have been reported.

'MRTC rejected the 1987 claw and wanted to use the older claw designs,' recounted Mr Bull.

In 1995, when a few claws were found dislodged, SMRT sought the advice of Brecknell Willis which suggested securing the claws at high-speed ramp areas with plastic cable ties as an interim measure.

SMRT, in turn, proposed adding a stainless steel housing to retain the claw and this was approved by the LTA.

The operator now intends to change all claws in the system to the latest fifth-generation ones which use cast stainless steel, instead of cast iron, and a secure bolt fitting to connect the claw and fastener.

Mr Bull also highlighted the 'critical importance' of material defects as noted in an experts' report directed by the Attorney-General's Chambers.

This report stated that the main cause of the Dec 15 incident was a defective fastener and flawed insulators in the claw assembly caused by manufacturing faults.

The same report noted that the Dec 17 incident was caused by a cracked third rail which was found to have been seriously weakened over a long period of use.

'Again, these are inherent and latent defects,' he said, noting, that the two unprecedented disruptions last December were a result of a 'rare confluence of factors'.

These factors, besides the claws and material defects, include the location of the incidents, vibration levels and upward forces on current-collecting devices.

None of these factors, individually, could have caused the disruptions.

Mr Bull also took time to defend SMRT's maintenance regime, noting it had a 'robust programme'. In some aspects, it was even more stringent than what was recommended by the manufacturers, he said.

As for 'wheel flats' - flat patches along the circumference of the wheel making the wheel no longer round - pointed out by LTA to be a probable contributing factor to claws being dislodged, this is an issue faced by all rail operators, said Mr Bull.

Since February, the SMRT has had two machines capable of fixing wheel flats on four cars a day, up from three.

SMRT has also taken active steps to deal with higher ridership, including running more services and buying more equipment for maintenance checks, said Mr Bull. 'Increased ridership and ageing infrastructure are important points of context which this committee should bear in mind,' he added.



LTA: Worn-out wheels can be a problem
Such defects produce higher vibration levels

By Goh Chin Lian, The Straits Times, 17 Apr 2012

THE Land Transport Authority (LTA) focused its opening statement yesterday on improvements that could be made to operator SMRT's maintenance regime.

Among them are making sure that train wheels that are worn out and flat, are reprofiled to their original roundness.

Such wheel defects have a bearing on the two major MRT breakdowns on Dec15 and 17, warned the lawyer representing LTA, Mr Andrew Yeo of Allen & Gledhill, who presented the statement.

In particular, measurements at the incident sites found that trains with wheel defects produced significantly higher levels of vibration than trains with properly reprofiled, round wheels.

Simulations carried out by Australian laboratory operator Vipac Engineers and Scientists showed that excessive vibration, together with other factors, can cause a metal claw that supports the power-supplying 'third rail' along the tracks to drop.

The other factors include the absence of a retaining clip that keeps the claw in place and the weight of the third rail no longer holding down the claw.

He said: 'It is reasonable to conclude that trains with wheel defects contributed to the occurrence of the incidents of Dec15 and 17, 2011.'

Despite the importance of maintaining train wheels in line with an increase in usage, SMRT reduced its wheel-profiling works from 2009 to last year.

'This is in spite of an increasing train fleet, increased ridership, increasing overall mileage and increased incidence of wheel defects over the same period as reported by SMRT.'

The operator's own investigation team also found that SMRT's maintenance expenditure and manpower headcount for maintaining trains and trackways have not been increasing in recent years at the same rate as the increase in the distance travelled per train, Mr Yeo noted.

So the LTA has recently instructed SMRT to check its entire fleet of trains for wheel defects and prioritise corrective works according to their level of severity, he said.

And while the LTA found SMRT's overall maintenance regime 'comprehensive and satisfactory', several other areas still needed improvement.

For instance, SMRT checked only some 'high-speed ramp' sections of the track for dropped claws, even though 79 per cent of reported dropped claws occurred along other sections.

Of concern, too, were the repeated misalignments of the third rail detected along various sections of the track before the incidents, and maintenance records found not to be properly kept.

SMRT was made responsible for maintenance, because the operator 'being in possession of the infrastructure which includes tracks and tunnels and the operating assets, is best placed to carry out proper and timely maintenance', he said.

The 26-page statement also suggested other reasons for the breakdowns. A part of the assembly system that supports the third rail above the tracks was probably broken before the first disruption, for example.

Damage to metal contact devices attached to the trains that glide along the third rail could also have remained after the first disruption and contributed to the second breakdown.

But the LTA ruled out two other causes: the design of new fourth-generation trains and the 'floating' slabs that tracks along the affected sections sit on.

Tests show that the vibration produced in both cases was insufficient to cause the claws to drop.

The LTA also noted that the two incidents could have been better managed, from communications with commuters, to briefing bus drivers on the routes along which to ferry stranded passengers.


AGC: Inquiry not meant to be adversarial

THE MRT breakdown inquiry is not an adversarial proceeding but a 'fact-finding and problem-solving' one, said Second Solicitor-General Lionel Yee in his opening statement in court yesterday.

He said he hoped the parties involved - namely train operator SMRT and regulator Land Transport Authority (LTA) - would approach the inquiry 'in a spirit of collaboration and cooperation'.

The evidence gathered by the Criminal Investigation Department (CID) in the past 13 weeks will be put before the Government-appointed Committee of Inquiry (COI) over the next six weeks.

'These proceedings may be taking place in a courtroom but they are not court proceedings where determinations of guilt or legal liability will be made in an adversarial setting,' Mr Yee said.

'Our focus must be instead on fact-finding and problem-solving.'

Mr Yee added that the COI 'owed it to the hundreds of thousands of commuters' to come up with measures to minimise breakdowns in future, and to mitigate the outcome of breakdowns if they were to happen again.

Nearly 450 exhibits - either documentary or physical in nature - are expected to be tendered during the inquiry.

At present, 108 witnesses have been lined up, but there are likely to be more. Of the lot, 97 are witnesses of fact, who will take the stand in the first three to four weeks of the inquiry.

They consist of train officers, station managers and staff, maintenance staff, service operations managers and customer service team leaders deployed to assist commuters during the two incidents.

Five officers from SMRT's operations control centre (the network's nerve centre) will also be called, as will three commuters affected by the first breakdown on Dec 15 - including a woman who fainted inside a stalled train.

A dozen senior SMRT executives, eight senior LTA officers and Assistant Superintendent Roy Lim of the CID will round off the witnesses of fact.

Expert witnesses include:
Mr Peter Gillens, an operational specialist from consultancy Gtrans International
Mr Andrew Barr, network operational planning and integration manager of London Underground who was the officer in charge during the 2005 terrorist attacks
Mr Richard Greer, a director of engineering group Arup who specialises in railway vibration and noise
Mr Jerry Evans, principal engineer of Interfleet Technology and a specialist in rail vehicle dynamics 
Mr Oliver Billings, senior engineer of Arup 
Dr Graham Brown, head of advanced analysis and test group at Sinclair Knight Merz
Dr Huang Xianya, vice-president and chief consultant for inspection and failure analysis at TUV SUD PSB, and
Dr David Ewins, professor of vibration engineering at London's Imperial College's Department of Mechanical Engineering.
The expert witnesses have already submitted various reports to the committee.
Mr Yee said the reports 'so far do not appear' to attribute the breakdowns to floating slab tracks or new China-assembled trains put into service in the middle of last year.



CID: Sabotage ruled out as cause of disruptions
By Royston Sim, The Straits Times, 17 Apr 2012

THE Criminal Investigation Department (CID) has ruled out sabotage as the cause of two major MRT disruptions last December.

CID lead investigator Roy Lim gave this answer to the Committee of Inquiry (COI) in response to a question from panel member Soh Wai Wah, director of prisons.

Citing earlier statements that ruled out the new fourth generation of trains and floating slab tracks as the possible causes behind the incidents, Mr Soh had asked whether the CID would say the same of sabotage.

Assistant Superintendent Lim said it had ruled that out, and added that he would cover this point in about two weeks' time during the second part of his investigation report which will cover expert findings.

Taking the stand as the first witness yesterday afternoon, he gave the background of SMRT's rail operations and a detailed chronology of what happened between Dec15 and 17 last year.

The committee heard how one SMRT train operator had seen sparks from the undercarriage, smelled a burning aroma and heard sounds on Dec15 before his train stalled at Braddell.

Another driver had heard a 'loud plastic dragging sound' coming from outside the train when it began to slow down at 6.45pm after departing from City Hall.

It soon stalled, and the last of an estimated 1,200 commuters arrived at Dhoby Ghaut at 8.05pm.

The evacuation by walking in the tunnel took one hour and 18 minutes.

ASP Lim also detailed the events of the Dec17 disruption, which lasted seven hours and nine minutes and affected about 94,000 commuters.

He added that SMRT had deployed a multi-function vehicle on the mornings of Dec16 and 17 to perform measurements and tests in the tunnels.

On Dec17, the vehicle's B-side mirror - which captures views of the third rail - was found cracked while in the tunnel and investigations had not been able to uncover the cause, ASP Lim said.

COI chairman Tan Siong Thye directed him and other parties to further investigate what had damaged the mirror.

Said Chief District Judge Tan: 'Things don't just happen like that.'



Committee of Inquiry: Who's who

THE members of the Committee of Inquiry are Chief District Judge Tan Siong Thye, director of prisons Soh Wai Wah and Professor Lim Mong King from Nanyang Technological University.

Second Solicitor-General Lionel Yee is representing the Attorney-General's Chambers.

Acting for the Land Transport Authority (LTA) is Mr Andrew Yeo of Allen & Gledhill.

SMRT's lawyer is Senior Counsel Cavinder Bull of Drew & Napier.

The inquiry will be conducted over the next six weeks and 108 witnesses have been lined up to testify. In the first three or four weeks, the committee will hear the testimonies of 97 'witnesses of fact'. These include SMRT train drivers, the staff of stations, maintenance and operations control, commuters and senior officers from LTA and SMRT.

The first witness, Assistant Superintendent Roy Lim who leads the Criminal Investigation Department's investigation, took the stand yesterday.

The 11 witnesses up next are specialists in rail operations and systems, rail engineering and vibrations.

They include vibration engineering specialist David Ewins from Imperial College London's Department of Mechanical Engineering and Mr Andrew Barr, the network operational planning and integration manager of the London Underground.

Mr Barr was the officer in charge of the London Underground's emergency response during the terrorist attacks of July 2005.


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