Wednesday 16 May 2012

MRT breakdown COI: Day 20

No engineers supervised rail checksTechnicians say they inspected train parts from up to 2m away
By Christopher Tan, The Straits Times, 15 May 2012

NO ENGINEERS were present to supervise the technicians who checked trains and tracks for damage after the first massive SMRT breakdown on Dec 15.

Yesterday, the Committee of Inquiry hearing, now in its fifth week, heard how the technicians had gone about their work that night.

SMRT assistant engineer Johari Abdullah was the first on the stand in the morning. He said he was told by the duty manager at Bishan depot to tell his technical crew to check the current collector devices (CCDs) of all trains returning on the night of Dec 15 for 'damage or abnormalities'.

The CCD is a part of the train that makes contact with the third rail, drawing electricity from it. Each train has 24 CCDs. Several CCDs on a number of trains were damaged after the Dec 15 incident.

Damaged and unrepaired CCDs were suspected of having caused the Dec 17 disruption.

The two disruptions affected more than 220,000 commuters.

Mr Johari described how the inspections were done. The trains would roll by a 'walkway' at a very low speed. Two technicians on either side inspected the CCDs visually from up to 2m away.

Five trains were found to have sustained CCD damage that night.

Technical officers Imran Ahmad and Aziz Ismail, who were the only ones paired to do the CCD inspections at Bishan on Dec 15, took the stand after lunch.

Said Mr Imran: 'This was the first time I saw so many trains with damaged CCDs.'

He added that as the trains were moving, and they were standing about 2m away, only major damage could be spotted. Minor or hairline cracks, he admitted, might have been missed.

Mr Aziz said that on top of inspecting the CCDs, he and Mr Imran had to check the temperature of the axle box - a part of the train connected to the wheels.

This was a routine but crucial check, as an overheated axle box could lead to bearings seizing and the train stalling.

Mr Aziz said that unlike Mr Imran, he did not have a walkie-talkie. He would make a note of what he spotted and shout to his partner, who would record the faults on a checklist.

He said he had about four seconds to inspect each CCD, contradicting Mr Johari's 'one to two minutes'. He also said he was not aware that he could stop the train for a closer look - again contrary to what his superior had said earlier.

The CCD inspection team did not know how many trains they inspected that night.

The last technical staff member to give evidence yesterday was acting assistant engineer Noor Effendi Sahari, who walked in the tunnels to straighten sections of the third rail that had become misaligned after the incident.

Accompanied by a private contractor, Mr Effendi said he made adjustments to the third rail by adjusting the bolts.

Asked by inquiry panellist Lim Mong King from the Nanyang Technological University's School of Mechanical and Aerospace Engineering how long a stretch he covered that night and whether it was straight or on a curve, he said it was about 100m and around a curve.

Professor Lim asked whether his 're-gauging' work was supervised by an engineer. Mr Effendi said 'no'.

Prof Lim asked: 'How do you know if you've done your work properly?' Mr Effendi said: 'Whenever I made an adjustment, I state it in my records.'

To which the professor said: 'So, then your work is done?'

'Yes,' he replied.

'Would anyone check your work?' Prof Lim asked.

'No,' he said.

For the most part, the Attorney- General's Office did most of the questioning yesterday, asking about minute details such as the width of the inspection walkway, the speed of trains as they rolled by, and the extent of the damage sustained by the trains.

The detailed fashion of the questioning contributed to a gross time overrun. Therefore, Land Transport Authority deputy group director Yeo Teck Guan's appearance on the stand had to be postponed again. He was supposed to have testified last week.

A conference of engineering and scientific experts - mostly from overseas - was also postponed.
At one point the inquiry chairman, Chief District Judge Tan Siong Thye, sounding a little exasperated, said: 'I don't know how I can expedite this proceeding... This is not a trial to establish culpability of anybody.'


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