10 February 2016

Controller error theory dismissed


The BBC has an article about the recent train crash in Germany:
German police have rejected a report that a line controller turned off an automatic safety system shortly before two passenger trains collided in Bavaria. An unconfirmed report suggested that an automatic braking system had been switched off to allow one of the trains to make up time. But a police spokesman rejected the theory as pure speculation. "Discard that, we reject that," a spokesman told local broadcaster Bayerischer Rundfunk.
The braking system, which is supposed to kick in when a train runs through a red light, was installed after a 2011 disaster at Magdeburg in which ten people died.
Reports in German media suggested that, in exceptional circumstances, the automated system could be overridden by rail staff. But police said the controller had been questioned as part of the inquiry, and there was no immediate suspicion of him. As the investigation was still in its early stages, nothing could be ruled out.
Human error is still being investigated as a possible cause of the disaster, which happened on a single-track commuter line on Monday morning near Bad Aibling, a spa town about sixty kilometers south-east of Munich, Germany. The control room at Bad Aibling is also at the center of the inquiry.
Transport Minister Alexander Dobrindt said the trains had crashed into each other while both were traveling at about a hundred kilometers an hour. Although the search for a third data recorder is still being carried out, Dobrindt told reporters that one of the "black boxes" had already been analyzed. No technical fault or evidence of driver error had been found on the westbound train, he said. But the eastbound train's data recorder may be of more importance, as it was several minutes late when the two trains crashed head-on.
The accident occurred on a single-track route between Rosenheim and Holzkirchen at 0648 local time. Officials say they assume both train drivers had no visual contact before the crash, as the site is on a bend, and they crashed into each other largely without braking. The stretch of line did have an automatic braking system designed to halt any train that passed a stop signal. It is not yet known why this failed to stop the crash.
Two of the three data recorders or "black boxes" on board the trains have been recovered.
Nine of the ten victims of the crash were men. Both train drivers and two train guards were among those killed. The tenth victim was a teenaged girl, according to local reports.
Police said that the search of the wreckage had been completed and no more victims had been found or were missing. None of those being treated in hospital was in a life-threatening condition, they added. 
Analysis by Richard Westcott, Transport correspondent:
It seems likely that one of the trains ran a red light, but it's hard to know why. It could be human error, technical problems, or a combination of the two.
The line is fitted with a modern safety system that slows the train down if it is going too fast, then stops it automatically if it passes a red signal. Drivers get warnings in the cab if there is a problem. The speed of each train suggests that neither had any warning.
It is highly likely they'd have known the route, too. Only by analyzing the "black boxes" will investigators know for sure what happened. It's incredible that so few people lost their lives, and that's almost certainly because of the huge improvements in train design over the years; they are much safer than they used to be.
The search has been complicated by the difficult terrain where the crash happened.
A hundred-ton crane arrived at the scene of the disaster, as salvage workers prepared to remove the two mangled trains from the track. The work was expected to last at least two days.
Bavarian State Premier Horst Seehofer laid a wreath at the site with his colleagues and said it was a tragedy. "The whole of Bavaria has been shaken," he said.
The trains collided in a hilly and densely wooded region near the Mangfall river.
Investigators will have to find out why a train that left Holzkirchen travelling east to Rosenheim was on the single track at 0648, four minutes after it was due to reach its next stop at Kolbermoor, where it would have met the westbound train on a double track.
The westbound train from Rosenheim to Holzkirchen would have left Kolbermoor at 0645, and would have been expected to be on the single track at the time of the accident.
As the PZB automated braking system had been checked a week ago, there has been heightened speculation that it may have been temporarily disabled, and it is the controller's responsibility to ensure trains are running safely.
In case signals fail, German railways are fitted with a final safety guard to prevent crashes. Cab signalling known as PZB (Punktfoermige Zugbeeinflussung or "intermittent train control") will set off an alarm in the driver's compartment when the train approaches a red light. If the driver does not respond by pressing a button, the train will brake automatically. 
Other fatal German train crashes:
January 2011: ten were killed at Magdeburg in Saxony-Anhalt when a commuter train collided with a freight train after the driver ran through two signals.
February 2000: nine died when an overnight train from Amsterdam, Holland to Basel, Switzerland crashed near Cologne in Germany.
June 1998: A hundred were killed when a high-speed train with a broken wheel derailed and smashed into a bridge at Eschede in Lower Saxony.
Rico says that no good German would turn off a safety system...

No comments:

 

Casino Deposit Bonus