On Fri, 10 Sep 2010 08:53:12 +0100
Roland Perry wrote:
In message , at 20:05:28
on Thu, 9 Sep 2010, remarked:

You would have thought the signal allowing trains out of the bay
platform would be interlocked to the points being set correctly for the
route over the crossover, wouldn't you?

Even in the presence of a fault condition (which they've apparently
admitted)?

So much for signals being failsafe. Failsafe unless the failsafe fails.
Which it obviously did.

B2003

The Standard's report says "It is the third train safety alert in three
months", which had me wondering what the other two were. I remember the
runaway rail grinder on the Northern Line, which the Standard mentions,
but it says that "the same 90-tonne train [i.e. the grinder] was
involved in a similar incident six weeks earlier on the Jubilee line".
I don't remember that one at all. Did I miss it or is this yet another
blunder by Dick Murray?

I note that in the online version of the story, the alleged Jubilee line
"similar incident" has become a "similar drama", and they've added
"although a London Underground spokeswoman denied the train was out of
control", which suggests that it was something quite different.
http://www.thisislondon.co.uk/standa...n-rush-hour.do
--
Richard J.
(to email me, swap 'uk' and 'yon' in address)

On 10 Sep, 09:46, "Richard J." wrote:
I note that in the online version of the story, the alleged Jubilee line
"similar incident" has become a "similar drama",

"drama" indeed. When I was at school, "drama" meant acting something
that wasn't real. It was based on made up words and made up actions.
Perhaps the word "drama" is, actually, appropriate for the "news"
source!

:-)

PhilD

--

wrote in message

On Fri, 10 Sep 2010 08:53:12 +0100
Roland Perry wrote:
In message , at
20:05:28 on Thu, 9 Sep 2010, remarked:

You would have thought the signal allowing trains out of the bay
platform would be interlocked to the points being set correctly for
the route over the crossover, wouldn't you?

Even in the presence of a fault condition (which they've apparently
admitted)?

So much for signals being failsafe. Failsafe unless the failsafe
fails. Which it obviously did.

Surely it was still failsafe? No trains were signalled to collide with
each other.

On Fri, 10 Sep 2010 11:38:30 +0100
"Recliner" wrote:
wrote in message

On Fri, 10 Sep 2010 08:53:12 +0100
Roland Perry wrote:
In message , at
20:05:28 on Thu, 9 Sep 2010, remarked:

You would have thought the signal allowing trains out of the bay
platform would be interlocked to the points being set correctly for
the route over the crossover, wouldn't you?

Even in the presence of a fault condition (which they've apparently
admitted)?

So much for signals being failsafe. Failsafe unless the failsafe
fails. Which it obviously did.

Surely it was still failsafe? No trains were signalled to collide with
each other.

Only because the oncoming train was still had 1km and some signals between it
and the station. If it had been 100 metres away we could be looking at a very
different situation.

B2003

In message , at 10:42:51 on Fri, 10 Sep
2010, d remarked:
Surely it was still failsafe? No trains were signalled to collide with
each other.

Only because the oncoming train was still had 1km and some signals between it
and the station. If it had been 100 metres away we could be looking at a very
different situation.

Is that speculation, or have you done a site visit and examined the
configuration of the signalling?

While one train got sent off the "wrong way", I don't think anyone has
said that this was combined with route setting/signalling from the
*opposite* direction having ignored that this wrong thing had happened.
--
Roland Perry

wrote in message

On Fri, 10 Sep 2010 11:38:30 +0100
"Recliner" wrote:
wrote in message

On Fri, 10 Sep 2010 08:53:12 +0100
Roland Perry wrote:
In message , at
20:05:28 on Thu, 9 Sep 2010,
remarked:

You would have thought the signal allowing trains out of the bay
platform would be interlocked to the points being set correctly
for the route over the crossover, wouldn't you?

Even in the presence of a fault condition (which they've apparently
admitted)?

So much for signals being failsafe. Failsafe unless the failsafe
fails. Which it obviously did.

Surely it was still failsafe? No trains were signalled to collide
with each other.

Only because the oncoming train was still had 1km and some signals
between it and the station. If it had been 100 metres away we could
be looking at a very different situation.

Not as I understand it. After all, Tube trains routinely follow each
other all the time, just a few hundred meters apart. They are signalled
along the same route, but the signals also stop them occupying the same
sections. So in this case, even if the trains were on a collision
course, surely the signals (and train stops) would actually have stopped
them approaching each other too closely?

On Sep 9, 2:05*pm, Roy Badami wrote:
On 09/09/10 13:34, Paul wrote:

Just saw this on BBC News

http://www.bbc.co.uk/news/uk-england-london-11242084

It is not clear from the report what the problem was, either human
error or mechanical failure. Interesting that it happened the morning
after the strike, although that may have nothing whatsoever to do with
it.

*From the limited information in the article, it sounds like a signaller
set the wrong route and the interlocks correctly prevented any
conflicting movements. *Doesn't sound like a safety issue to me.

* * *-roy

Not at all. The points moved after the signal was cleared. Would be
impressive if a signaller could do that.

On Sep 10, 11:38*am, "Recliner" wrote:
wrote in message



On Fri, 10 Sep 2010 08:53:12 +0100
Roland Perry wrote:
In message , at
20:05:28 on Thu, 9 Sep 2010, remarked:

You would have thought the signal allowing trains out of the bay
platform would be interlocked to the points being set correctly for
the route over the crossover, wouldn't you?

Even in the presence of a fault condition (which they've apparently
admitted)?

So much for signals being failsafe. Failsafe unless the failsafe
fails. Which it obviously did.

Surely it was still failsafe? *No trains were signalled to collide with
each other.

Yes they were. One train was on the line working in the wrong
direction. Would you drive the wrong way on a motorway?

On Sep 10, 11:59*am, "Recliner" wrote:
wrote in message





On Fri, 10 Sep 2010 11:38:30 +0100
"Recliner" wrote:
wrote in message

On Fri, 10 Sep 2010 08:53:12 +0100
Roland Perry wrote:
In message , at
20:05:28 on Thu, 9 Sep 2010,
remarked:

You would have thought the signal allowing trains out of the bay
platform would be interlocked to the points being set correctly
for the route over the crossover, wouldn't you?

Even in the presence of a fault condition (which they've apparently
admitted)?

So much for signals being failsafe. Failsafe unless the failsafe
fails. Which it obviously did.

Surely it was still failsafe? *No trains were signalled to collide
with each other.

Only because the oncoming train was still had 1km and some signals
between it and the station. If it had been 100 metres away we could
be looking at a very different situation.

Not as I understand it. After all, Tube trains routinely follow each
other all the time, just a few hundred meters apart. They are signalled
along the same route, but the signals also stop them occupying the same
sections. So in this case, even if the trains were on a collision
course, surely the signals (and train stops) would actually have stopped
them approaching each other too closely?

That is working in the same direction. At junctions where trains are
"head on", the signalling would act to stop a train clear of any
conflicting move if, for example a SPAD occured. A train on the wrong
line doesn't have this benefit. Boltar seems to know what he's talking
about.