On Jul 16, 7:11*pm, Charles Ellson wrote:

Indeed. It always seemed strange that LU were allowed to get away with
a single bell as a start signal with AFAIAA no confirmation response
from the driver long after a safer practice had been established on
BR. As well as the circumstances you describe, a single bell allows
for the signal to be given just as a danger is observed which on BR
would still have to be followed by the second press before the driver
moved off. IMU there was no LU equivalent to a BR stop/one-bell signal
(and if a door bounced open or the detection circuit failed it would
not have been possible) leaving only the emergency brake valve
available for use.

- Show quoted text -

Would it not be the case that the reason this system was kept in
place is that it actually worked? I do not recall hearing too many
tales of people falling out of trains or being drgagged along the
platform. If you give a driver "one" on the bell he has to react, the
thinking time required to acknowledge the bell - that means I need to
brake, then put the brake "in". is surely longer than a guard standing
by a "handle" seeing a problem and simply operating that handle. That
takes away the need for the delay in driver reaction and the time
taken for the gaurd to acknowledge it and operate the bell has been
used pulling the hanndle.

Other may have anecdotes from before my cranking days to suggest
otherwise, but it seems to me to have been a fairly efficient system.

Richard

On Sun, 17 Jul 2011 01:53:17 -0700 (PDT), Fat richard
wrote:

On Jul 16, 7:11*pm, Charles Ellson wrote:

Indeed. It always seemed strange that LU were allowed to get away with
a single bell as a start signal with AFAIAA no confirmation response
from the driver long after a safer practice had been established on
BR. As well as the circumstances you describe, a single bell allows
for the signal to be given just as a danger is observed which on BR
would still have to be followed by the second press before the driver
moved off. IMU there was no LU equivalent to a BR stop/one-bell signal
(and if a door bounced open or the detection circuit failed it would
not have been possible) leaving only the emergency brake valve
available for use.

- Show quoted text -

Would it not be the case that the reason this system was kept in
place is that it actually worked?

Like "stop and proceed", another Underground specialty with a string
of lethal consequences over the years ?

I do not recall hearing too many
tales of people falling out of trains or being drgagged along the
platform. If you give a driver "one" on the bell he has to react, the
thinking time required to acknowledge the bell - that means I need to
brake, then put the brake "in". is surely longer than a guard standing
by a "handle" seeing a problem and simply operating that handle.

Half the time the guard was not standing on the same side as the
emergency brake, the other times he was still not that close to it.

That
takes away the need for the delay in driver reaction and the time
taken for the gaurd to acknowledge it and operate the bell has been
used pulling the hanndle.

Other may have anecdotes from before my cranking days to suggest
otherwise, but it seems to me to have been a fairly efficient system.

Like "stop and proceed", another Underground specialty with a string
of lethal consequences over the years ?

Generally the stop and proceed rule works fine and is used thousands of
times a year on the Underground. The problem is mostly driver error with
the driver going too fast (too fast so that they can't stop short of any
obstruction - e,g, a train in front) or resuming speed too soon (at a
wrong signal).

Most of the staff errors have been overcome over the year by fitting Speed
Control After Tripping (SCAT) to trains which limits the speed to about
9mph after resetting the tripcock. In fact it always used to be taught
that the speed after applying the rule was "3 to 5mph" or "so you can
count the sleepers".

Roger