Seoul Metro Line 2 collision

[bikkuri bahn]

I'm surprised there has been little chatter on the net about this accident (none in the rail-oriented forums I frequent).  Perhaps the ferry disaster is overshadowing everything.  Anyway, this article has the most info about the possible cause, though it is not 100% accurate, either because of translation issues, or reporter ignorance of railway technology and operation:

 

 

Clues emerge in subway collision Older safety system still used on line No. 2 is disabled by drivers May 07,2014

Drivers of subway trains in Seoul often flick off a safety system that prevents crashes because it’s buggy, which may have been a contributing factor to the rear-ending on Seoul Metro line No. 2 Friday that injured more than 200 passengers.

 

 

Several lines, including line No. 2, have automatic train-stopping systems (ATS). Developed in Japan in the 1980s and 1990s, the system is designed to stop a subway train within five minutes* if it does not halt at a “stop” signal in order to prevent crashes, according to Seoul Metro.

*make that five seconds

 

Following those two signals, he saw a “stop” signal after he rounded a curve. He said he stepped on the brake pedal*, but failed to stop the train immediately, only to crash into the back of the train ahead.

 

*lol

 

http://koreajoongangdaily.joins.com/news/article/Article.aspx?aid=2988786

 

A better written article than the one above:

http://koreajoongangdaily.joins.com/news/article/Article.aspx?aid=2988852

 

An eastbound train on Seoul Metro line No. 2 leaving Sangwangsimni Station in Seongdong District, eastern Seoul, was rear-ended Friday by another train that failed to stop at a signal. The focus is now on the ATS, an older system from the 1980s and 1990s that seems to not sync with a newer system also being used in the Seoul subway system.

 

The report written in 2009 by a former member of the signal division of the company, Koh Chang-seok, warns that the use of the incompatible systems could cause disruptions.

The report found that in January 2007 alone, the ATS had technical glitches on 199 occasions. The ATS is older analog technology, while the automatic train-operation system (ATO) is new and digital.

Currently, 38 trains are using ATO, which was developed by Siemens and other companies in the 2000s. There are still 50 trains using ATS, which was developed in Japan in the 1980s and ’90s. The ATO system was introduced in 2007, which triggered mechanical conflicts with the older system.

“In the first three years, there were a number of disruptions because of compatibility issues between the two systems,” said an employee of Seoul Metro who asked not to be identified.

 

 

Hmm, maybe Seoul Metro officials would benefit with a visit to Tokyo Metro's Fukutoshin Line, where rolling stock is fitted with five different signaling systems: CS-ATC, ATO, ATC-P, Tobu ATS, and Seibu ATS- that work smoothly and safely.

Edited May 8, 2014 by bikkuri bahn

[kvp]

Reminds me of the old Budapest underground line 1 ATS system from 1896 (19th century!). The system simply removes the electricity from the blocks behind a red signal. Since the old trains were all electric with a spring force storage parking brake connected serially to the traction motors (like most elevator motors of the time), removing the power resulted in full brake application. This system was demonstrated for a film crew a few years ago with the museum car number 11 of the old 1896 stock which still in operating condition. You can't override this. (other than this, signalling was originally controlled by a prototype electromagnetic sensor system supplied by Siemens & Halske along with the high voltage 300V traction equipment) The 'new' rolling stock made by Ganz 40 years ago is using 'modern' electropneumatic control and still stops automatically when passing a red signal. The usual accidents on the line are slow speed derailments on the ancient turnouts at the terminal stations and a train or two breaking down once in a while.

 

I just wonder what happened with this engineering knowledge during the last 2 centuries? (for example, the new simens ato on line 4 can't really work reliably with the french trains so they have to run them with guards sitting besides the driver, while the original underground is using driver only operation since the start)

[Mudkip Orange]

I read about this on fark. The headline read:

 

170 injured on SEOUL TRAIN