IP: A bit more from RISKS on the German train disaster

[Dave Farber <farber () cis upenn edu>]

Date: Sun, 7 Jun 1998 16:48:12 +0200 (MEST)
From: Martin Virtel <virtel () zeit de>
Subject: German high-speed train disaster


Tabloid magazine *Neue Revue* quotes a survivor, Wolf-Rüdiger
Schliebener, confirming earlier news that passengers heard strange noises
about two minutes before the disaster, while the train started rocking and
shaking.  As the broken wheel (thought to be the cause of the disaster) was
located somewhere in the second unit, the driver up in front didn't notice
anything.


After the wheel broke, the train continued going on for two minutes at its
cruise speed of 200 km/h, until the broken wheel destabilized the whole
train and the last part of it went off the rail and hit a bridge.


The point Schliebener made was that passengers noticed something was wrong,
but the train lacked appropriate emergency brakes or any other means of
telling the driver that there was something wrong.  Which is true?  AFAIK:
there are two emergency brakes located at the doors, but none within the
cabin (which, for non-Germans, looks pretty much like a airplanes cabin,
whith two rows of seats on each side).  Schliebener told *Neue Revue* he
wondered why the driver did not start to brake.  In effect, he never did:
the train was stopped automatically after all but the first unit went off
the rails. The driver seemed surprised - he hadn't noticed anything until
the train stopped automatically.


Frank Drieschner, our reporter who went to cover the disaster, was told by
railway staff that the train's steering electronics prevent the driver from
doing anything meaningful (letting the computer do everything instead) at
speeds over 160 km/h, so if there had been emergency brakes near, they'd
probably have been disabled automatically at high speeds.


Another thing Frank told me was that the cable on the rails used by the
train control system was completely destroyed between the point where the
wheel broke and the point where the train hit the bridge.  An interruption
of the cable should make the train brake automatically, railway staff told
him.


So far, there have not been any definitive conclusions on the accident. 


  [Added comment:] Whatever resonance one can imagine interferes with the
  operation of trains, the presence of proper "something is going wrong"
  feedback systems (either from the passengers via an emergency break, as I
  suggested, or a automatic one, as the next issue of Der Spiegel claims is
  installed in British high-speed trains and was dropped by the German
  railway authorities because it was too expensive) would have been of help
  in this case.


  Only imagine the passengers in the train having to remain passive as the
  train went on shaking and rattling at 200 km/h for two minutes before the
  crash.


  On the other hand, there can be a "too much flashing warning lights in the
  cockpit" problem, as several reconstructions of airplane crashes have shown.


Martin Virtel, DIE ZEIT im Internet (http://www.zeit.de)  +49 (0)40-3280-562


  [The German train disaster toll is now up to 102 people killed.]