John

Thank you for this and I look forward to your feedback.

There are several issues here. What you seem to be thinking of is
track condition monitoring. This is well known on mainline railways,
BR used to have a pair of trains which measured track condition by
observing ride quality - an unexpected bump or sway generated a
record, which was followed up, and a squirt of whitewash onto the
track, so that the fault could be found on foot. BR tried to "do" the
whole network on a regular basis. There is a quite separate technology
which detects cracks by sending ultrasonic waves down into the rails,
and if an echo is received BEFORE the echo from the bottom of the
rail, it shows a discontinuity, ie a crack. To get accoustic coupling
you have to put water between the accoustic head and the rail top, and
this imposed a speed limit, so that detector trains couldn't keep up
with general traffic, so had to be scheduled to run at night, very
inconvenient!

This is all very good and necessary. And there is also equipment for
monitoring the condition of wheels, axles, etc. But I don't know of
any railway operator who fits his trains (or trams, which are at
rather greater risk of derailment because their tracks are so much
more liable to interference) with equipment to detect when a
derailment has actually occured.


Regards

Michael Bell

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In article , JDikseun
wrote:
Anything that saves lives/prevents accidents must be a good idea, and
deserves investigation.

Monitoring trains is done to a very limited extent to evaluate ride
quality - once every 2 months, I think - using portable equipment that
is removed from the train after each journey. Which is a start.
A couple of trains on each line could be instrumented permanently,
this would give some sort of control over ride quality, and reduce the
risk of derailment caused by track condition. Monitoring every train
might be too expensive at this stage, but will probably become viable
with future improvements in technology.

I'll see what I can find on derailment info and get back to you.

John


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