Monday, May 24, 2010

Subang airport closed after lightning strikes runway

Lightning on Tuesday created three holes in the middle of the runway, each one averaging 60cm in diameter and 15cm deep.
Subang airport closed after lightning strikes runway

PETALING JAYA - The Sultan Abdul Aziz Shah airport in Subang was partially closed for an hour after lightning damaged its runway during a thunderstorm.
Department of Civil Aviation director-general Datuk Azharud­din Abdul Rahman said lightning on Wednesday created three holes in the middle of the runway, each one averaging 60cm in diameter and 15cm deep.
“By 6.15pm, the holes had been patched up and the airport was fully operational again,” Azharud­din told The Star.
No aircraft was struck by lightning during the storm yesterday, he said.
A Meteorological Department spokesman said severe thunderstorms were normal during the inter-monsoon season.
“Rain will be accompanied by lightning and thunder. The storm also causes a strong downdraft, making it very windy,” he said.
It rained from 4pm to 6pm yesterday, pouring heavily for the first hour before easing in the second hour, he added.
Ipoh Timur MP Lim Kit Siang was among passengers stranded at the airport due to the lightning strike.
His flight to Penang was originally scheduled to depart at 5.30pm, but was postponed to 8.30pm.
The heavy downpour also damaged the broadcast room of the International Broadcast Centre at Putra Stadium here where players were training before the Thomas Cup and Uber Cup Finals this month.
A portion of the ceiling caved in in the 5.15pm incident.
Building and maintenance workers immediately rushed to the scene.
No one was injured as the room was empty when the incident happened.
The rain also caused massive traffic jams and flash floods in several areas of the city.

Monday, May 17, 2010

Singapore - Lightning strike caused major disruptions to SMRT

April 23 rail incident among "more major" disruptions: SMRT
By Neo Chai Chin | Posted: 04 May 201





SINGAPORE: The lightning strike on the Bukit Panjang light rail transit network nearly two weeks ago, was one of several that have disrupted rail services in the last decade. And it was one of the more major incidents, damaging the power equipment of one of the trains, according to operator SMRT.

But lightning strikes don't always spell bad news for commuters, according to a lightning protection expert.

This is because of the lightning protection devices in place, which could reduce potential damage by 90 per cent, said Professor Liew Ah Choy, an electrical and computer engineering don at the National University of Singapore.

This means that in 10 instances of a lightning strike, only one incident would cause service disruption.

The devices include lightning protection tape on the rails and surge arresters to limit potential damage to the rail network's electronic systems.

The tape safeguards against direct strikes on the rail. "When the lightning current gets injected into the lightning protection tape, there will be a large voltage rise and a lot of current flowing, and a very large magnetic field generated," explained Professor Liew.

The "very high" voltages induced by lightning vary from several kilovolts to 100 kilovolts, and can cause power failure.

But in some instances, the surge arresters are able to limit the voltage values so that no damage is caused, said Prof Liew.

While no lightning protection safeguard is fail-proof, Singapore has done a good job of minimising the frequency of disruption, he said.

Since the Bukit Panjang LRT system began operations in 1999, there have been three instance of delays caused by power surges, said Mr Tay Tien Seng, SMRT's light rail operations director.

In the April 23 incident, engineers managed to get one of the trains functioning again, while a rescue train was sent to push the second defective train to the nearest station.

About 100 passengers were on the two trains, but none was in danger at any time during the incident, said SMRT in a statement after the incident.

However, a 60-year-old Bukit Panjang resident, Mr Chen, who was affected by the disruption, said station staff could have done more to prevent would-be passengers from scanning their cards and heading up to the train platform.

Had there not been a thunderstorm, passengers could have got off the train and walked on the track to the nearest station, said Mr Tay.

They would have walked a safe middle passage flanked by the train tracks.

Meanwhile, last month's disruption also threw up another interesting statistic.

Three other lightning-induced train disruptions reported in the media since 2001 have also occurred in April - one of the months with the most thunder days alongside May and November/December, according to statistics from the National Environment Agency. - CNA/vm

Monday, May 10, 2010

ESE EUROPEAN NATIONAL STANDARS ARE IN FORCE AND NOT IN CONFLICT WITH EN-62305

The CENELEC Technical Board (BT) has finally put an end   to a “debate” initiated by some European standardization National Committees.
For more than a year, some persons involved in Lightning Protection standardization, members of organizations and manufacturers of conventional Lightning protection systems have raised a so-called “conflict” between, on one side, the French ESE standard NF C 17-102 and similar standards in Spain, Portugal , Slovakia, etc… and, on the other side, the last CENELEC lightning protection standards EN 62 305 series (based on the IEC series). For a while, this so-called “conflict” was considered as the “ultimate” tool discovered by anti-ESE lobbyists to definitely eliminate this technology and its standards by an unfair use of the administrative procedures of CENELEC.The CENELEC BT  has then been overwhelmed by an abundant literature supposedly demonstrating the urgent need to withdraw the corresponding standards.
But the CENELEC Technical Board decision No 136/013 published after its April 2010 meeting does not follow these “experts” conclusions and predications. CENELEC BT refused by two times to consider the standards as being in conflict and decided to have the national ESE standards existing providing they are clearly stating that they are dealing with different topic than EN 62305 standards series especially by making no reference to EN 62305 series.

A new version of the ESE national Standards should then be published accordingly.
CENELEC BT also proposed that the resulting E.S.E. standards should be proposed to I.E.C. as international draft standard.