MRT breakdown COI: Day 2

Why was more secure claw design rejected 25 years ago?

Question asked on the second day of hearing into MRT breakdowns

By Christopher Tan, The Straits Times, 18 Apr 2012

THE spotlight on the second day of the hearing by the MRT breakdown Committee of Inquiry (COI) fell on a small but crucial object - the metal claws that kept the power-supplying 'third rail' in place.



Mr Andrew Yeo, counsel for the Land Transport Authority (LTA), wanted SMRT lawyer Cavinder Bull to clarify his assertion that a vibration-proof claw model was available 25 years ago, when Singapore's first MRT lines were being built.

Mr Bull, in his opening statement on Monday, had stated that MRTC - the rail builder that eventually became a part of the LTA - had rejected an improved claw design way back in 1987.

In the massive breakdowns in December, 21 third rail claws were found dislodged, causing the power-supplying 'third rail' to sag and disrupting power supply to the trains.

Mr Bull, from Drew & Napier, said claw supplier Brecknell Willis had in 1987 presented to the MRTC the new claw, which had a 'split pin locking system' that prevented dislodgement even under 'severe vibration'.

Quoting Brecknell Willis, Mr Bull said this claw model had been used in various metro systems - including Taipei, Copenhagen, Oslo and Sao Paulo - with no reported failures.

But MRTC, he said, had rejected it and stuck to the original claw. Some of these claws had 'spring clips' to help them withstand vibration better.

LTA lawyer Andrew Yeo, from Allen & Gledhill, said however that Brecknell Willis' proposal was made for Phase II of the MRT system, and not for Phase I.

Phase I was the North-South line from Novena to City Hall, not Phase II, he said. This was the stretch where the December incidents occurred. Phase II was not where the December breakdowns took place.

Mr Yeo went over what Mr Bull said a number of times - until the COI chairman, Judge Tan Siong Thye, interjected.

The judge said the pertinent point should be why MRTC did not adopt the more secure claw design.

'We are interested in why the split-pin design was not used,' he said.

Mr Yeo said he needed time to 'look into the matter', which pre-dated the 1995 formation of the LTA.

Also, Brecknell Willis was a sub-contractor, he pointed out, and sub-contractors normally deal with the main contractor - which was not MRTC.

Judge Tan also said he found it 'puzzling' that two claw designs were eventually used: the original, and one with a 'spring clip'.

Mr Bull replied that the 'spring clip' claws were used in sections of the network that had 'floating slab tracks' - insulated sections underneath high-rise developments to shield them from the noise and vibration of passing trains.

The original claw, he said, had tended to 'jump out' along floating slab tracks during test runs.

One COI member, Professor Lim Mong King of Nanyang Technological University, commented that he spotted claws with clips and others without during a site visit before the inquiry.

Mr Yeo said 'the intention was for all claw assemblies to have spring clips... maybe some have fallen off over time'.

Judge pinpoints discrepancies, seeks details
By Royston Sim & Maria Almenoar, The Straits Times, 18 Apr 2012

CHIEF District Judge Tan Siong Thye, apparently unfazed by the technical details emerging in the inquiry into December's train disruptions, interjected at several points yesterday - at times to ask questions, and at others, to point out discrepancies.

And in homing in on the key details, he made it clear where his committee's interests lay - in fact-finding, which was why he was more 'intrusive' than he would be in an adversarial trial, he said.

'If there are lapses, so be it... We'll rectify it and life goes on.'

He said, however, that the Land Transport Authority, SMRT and the Attorney-General's Chambers would need to address the queries he raised in the coming weeks.

For the second time in two days, as head of a three-man committee, he zeroed in on key areas troubling him.

One is how SMRT's maintenance staff are able to spot defects in the third rail claw assembly, given that it is covered by an opaque fibre-glass casing.

He said he had 'grave doubts' that staff patrolling the tracks would know when a rail claw has come loose. He noted that these officers could not possibly open each and every cover when conducting their nightly checks. They may be able to spot dropped claws, but how can they identify loosened claws, he asked.

SMRT's lawyer, Senior Counsel Cavinder Bull, voiced concern that this line of questioning cast aspersions on the work these patrolmen and maintenance officers do.

'These individuals have a job and they do their job,' said Mr Bull.

He added that witnesses to be presented before the court in due course would address Chief District Judge Tan's queries.

Another sticking point which the judge revisited for the second time in two days lay with the collector shoes used by trains to draw power from the third rail.

How many collector shoes can an MRT train afford to lose before it is unable to run any further, he asked.

He noted that it was 'very interesting' that while 11 trains had damaged collector shoes after the Dec 17 incident, only five had stalled; six continued running.

He also picked up on a discrepancy of facts between the opening statements given by Second Solicitor-General Lionel Yee, who is representing the Attorney-General's Chambers, and Mr Bull.

The two had cited different trains as being the first one to stall on Dec 15.

It turned out later that Mr Bull's statement was the accurate one.

Yesterday's hearing primarily centred on Mr Yee's clarifications about the findings of the Criminal Investigation Department (CID), as presented by CID lead investigator Roy Lim.

At one point, the panel fired several questions at Assistant Superintendent Lim, pressing him to explain the flexibility of a collector shoe. How far would it go before it hits breaking point, the panel wanted to know.

But Chief District Judge Tan, recognising later that ASP Lim could not answer this, said: 'We will hold our horses and ask the relevant person for more details.'

The hearing continues today.

Related

MRT breakdown chaos, COI-Day 1