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vehicle was somewhat larger, and the train speed much higher, but there was no
excuse for the conduct of some of those involved, including the police
escort. It could happen again, because in the UK, level crossings are the only
places on the railway which are not proved to be clear before setting th signals
to allow trains to proceed. The only protection is the assumption that all road
vehicles will clear the crossing within the set time. As a designer of safety
systems, I have to say that a system like that, used extensively worldwide, not
just in the UK, is fundamentally unsafe, as it relies totally on all road users
clearing the crossing on time, regardless of any problems such as mechanical
breakdowns, and of course gross stupidity. In the old days, there would be a
signal box with the facility to stop trains at each level crossing, and trains
would not be allowed to proceed until the gates were locked against road traffic
and the crossing was seen to be clear. There are systems which are being
trialled, following the apparent suicide, which killed a number of people
including the innocent train driver, at Uften Nervet,
which will prove that the crossing is clear of at least large objects, but these
systems are still not the answer, unless they are properly interlocked with the
signalling. Four aspect signalling is universal on fast UK main lines, and it
needs three consecutive signals, double yellow, single yellow, and red, to
actually stop a train. That takes much more than 24 seconds, so a safe,
interlocked system would cause much more delay than at present to road
traffic. Railway signalling designers (I have worked in that industry) are
almost always very good, and are more paranoid than any other safety critical
system designers, covering all sorts of eventualities which would not be
considered in other fields, yet they seem to be utterly blind to this huge hole
in the safety systems, maybe because they just can't do anything about it due to
other constraints. Much the same considerations apply in Australia, but the
train speeds are somewhat lower. [ Reply to This | Parent | # ]
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