Distants and Repeaters

[D Foster]

I'm confused!

On the signal identification plates a triangle denotes a Distant signal and an R suffix to the number indicates a Repeater signal...
So what, please, is a signal with both?
A Distant for a Repeater or a Repeater for a Distant (aka and Outer Distant)?

However - I was under the impression that Distants only occurred in Absolute Block (and derivatives) while Repeaters only occurred in TC Block.

Signals with these plates seem to occur all over the system with no apparent logic that I can see.

Thanks

 

[Elecman]

Try this from Railsigns

In 1996, the 'delta' plate, bearing a triangular symbol, was introduced as a means of identifying colour light distant signals without reference to the signal's number. In most new schemes since, distant signals have been uniquely numbered, without a suffix. On some schemes, however, distant signals continued to be numbered with the R or RR suffix in addition to the delta plate, to maintain consistency with adjacent areas.

So the R didn't mean repeater but distant in these cases

 

[455driver]

On the Mainline there are no 'repeater' signals, there are however distant signals (IE cannot show a red aspect) that are plated with an 'R' after the signal number which is a copy of the signal number they relate to-

A123R is the distant for A123 (stop) signal etc.

 

[scott118]

On the Mainline there are no 'repeater' signals, there are however distant signals (IE cannot show a red aspect) that are plated with an 'R' after the signal number which is a copy of the signal number they relate to-

A123R is the distant for A123 (stop) signal etc.

only banner repeaters...anyone mention co-actors?

 

[driver_m]

Just to further muddy the waters Talacre has a distant signal plated as an R. It's AB throughout. You'd have to ask a signaller who could answer better but I'm guessing this means it clears when the home and/or section signals are cleared and not pulled separately like at Prestatyn next door which does have a pulled semaphore distant on the up.

 

[Railsigns]

I'm confused!

On the signal identification plates a triangle denotes a Distant signal and an R suffix to the number indicates a Repeater signal...
So what, please, is a signal with both?
A Distant for a Repeater or a Repeater for a Distant (aka and Outer Distant)?

However - I was under the impression that Distants only occurred in Absolute Block (and derivatives) while Repeaters only occurred in TC Block.

Signals with these plates seem to occur all over the system with no apparent logic that I can see.

What's confusing you is thinking that distant signals and repeater signals are two different things when they are in fact the same. Nowadays, 'distant signal' refers to any signal that cannot display a stop aspect. It makes no difference if it's an Absolute Block area or TCB or whatever.

Some distant signals are identified by an "R" suffix ("RR" in the case of an outer distant). Some distant signals are identified by a 'delta' symbol. Some are identified by both these methods. No significance can be drawn from the method of identification other than perhaps the age of the installation.

 

[Old Hill Bank]

only banner repeaters...anyone mention co-actors?

There are still co-actors as you leave New Steet east end tunnels I presume?

 

[D Foster]

In my experience Co-Acting signals are suffixed "CA" and Banner Repeaters are suffixed BR.

"In my day"... Not that long since... Again "in my experience" - Distants were the yellow-most-restrictive-aspect on AB schemes while yellow-most-restrictive on TCB schemes were "Repeaters".
To the best of my knowledge those "Repeaters" - as Colour Light signals in TCB - automatically changed up or down following the proving of the aspect of the Stop Signal to which they applied. (Or, if they were Y G Y approaching multiple aspects, to the two Stop Signals two which they applied). Not having their own, separate lever (or other) control they were (even at the greater distance than would apply for a Banner Repeater) classed as repeaters rather than Distants.
I don't know for certain how accurate this is/was or if there has been a change. If it did change - does anyone know when please?

One suggestion that I have been given by an IRSE bod is that the triangle and R together might be used when a Distant is co-acting (in proved sequence) with its Stop Signal - and probably on the same lever. (red-over-yellow).
I suppose that Yellow-most-restrictive being called a Distant on TCB would enable this principle to make sense in a TCB area as well as an AB area.

Whatever happened to Red Distants and Drivers knowing where they are by route knowledge???

Thanks all
--- old post above --- --- new post below ---
Then, of course, there's the weird LNER arrangement of automatic Distants on the (heritage) GCR - and with GWR signals just to confuse.
(That may be wandering from the straight-and-narrow of current practice on NWR though...

 

[headshot119]

Just to further muddy the waters Talacre has a distant signal plated as an R. It's AB throughout. You'd have to ask a signaller who could answer better but I'm guessing this means it clears when the home and/or section signals are cleared and not pulled separately like at Prestatyn next door which does have a pulled semaphore distant on the up.

Actually the distant signals on both lines at Talacre are played with an "R" suffix.

Both are colour lights, and both read onto a three aspect colour light home signal, which then reads onto a semaphore section signal.

They will clear to green when the relevant home signal lever is revered in the frame. Assuming the replacement switch hasn't been operated, so although they don't have seperate levers they can in effect be controlled.

When the home signal lever is reversed the home signal wil step up to a yellow aspect, and will only step up to green when the section signal lever is reversed.

 

[D Foster]

There's absolutely nothing like confusing the issue is there?

For a time back in the early 80s Reigate's Down signals were - CL Distant, Semaphore Outer Home, Semaphore Inner Home, CL 3 aspect Starter (end of the Down Platform and protecting the Level Crossing) and Semaphore Advanced Starter.
When cleared the Starter showed Yellow onto the Advanced when it was On and changed up to green when the Starter/Section Signal was cleared.
I suspect that this and similar arrangements were used at other places - it would be very interesting to know of other examples... Please

 

[edwin_m]

Actually the distant signals on both lines at Talacre are played with an "R" suffix.

Both are colour lights, and both read onto a three aspect colour light home signal, which then reads onto a semaphore section signal.

They will clear to green when the relevant home signal lever is revered in the frame. Assuming the replacement switch hasn't been operated, so although they don't have seperate levers they can in effect be controlled.

When the home signal lever is reversed the home signal wil step up to a yellow aspect, and will only step up to green when the section signal lever is reversed.

Presume this means that there is full braking distance from the home signal to the section signal. If not then the distant would have to remain at yellow until both home and section signals are cleared.

 

[Phil.]

Try this from Railsigns

In 1996, the 'delta' plate, bearing a triangular symbol, was introduced as a means of identifying colour light distant signals without reference to the signal's number. In most new schemes since, distant signals have been uniquely numbered, without a suffix. On some schemes, however, distant signals continued to be numbered with the R or RR suffix in addition to the delta plate, to maintain consistency with adjacent areas.

So the R didn't mean repeater but distant in these cases

The "R" meant related.

 

[Railsigns]

The "R" meant related.

[citation needed]

 

[John Webb]

There's absolutely nothing like confusing the issue is there?

For a time back in the early 80s Reigate's Down signals were - CL Distant, Semaphore Outer Home, Semaphore Inner Home, CL 3 aspect Starter (end of the Down Platform and protecting the Level Crossing) and Semaphore Advanced Starter.
When cleared the Starter showed Yellow onto the Advanced when it was On and changed up to green when the Starter/Section Signal was cleared.
I suspect that this and similar arrangements were used at other places - it would be very interesting to know of other examples... Please

In 1973 St Albans South was fitted with a ground-mounted 3-aspect signal at the London end of the down slow platform to allow trains back onto the up slow and so return to London as service trains or ECS. When cleared the signal showed a yellow aspect until the up slow starter was cleared, when it then showed green. With the exception of distant signals this was the only CLS amidst the semaphores. Picture herewith - top 2 aspects of signal just visible(click on picture to go to larger original):
Approaching St. Albans City

© Copyright Martin Addison and licensed for reuse under this Creative Commons Licence.

 

[FordFocus]

Always treated R and Triangles the same, call them either distance or repeater signals.

New signalling schemes seem to number distant signals individually now.

 

[driver_m]

Actually the distant signals on both lines at Talacre are played with an "R" suffix.

Both are colour lights, and both read onto a three aspect colour light home signal, which then reads onto a semaphore section signal.

They will clear to green when the relevant home signal lever is revered in the frame. Assuming the replacement switch hasn't been operated, so although they don't have seperate levers they can in effect be controlled.

When the home signal lever is reversed the home signal wil step up to a yellow aspect, and will only step up to green when the section signal lever is reversed.

That shouldn't really happen though should it.. I'd be rather unhappy about passing a green distant in an AB section only to find the home signal showing one yellow at Talacre and expecting to get a voyager doing 85 down to 0 at the section signal, especially when a green distant is supposed to signify that the section is clear throughout. Guessing again but there must be some track approach control at that particular box for that scenario. The NW mainline has strange signalling though even for AB. Can't be many areas that have a Track Circuit Block area within AB areas covering both ends of the boxes' control. (Bangor and Llandudno Jn)

 

[Tomnick]

A distant signal 'off' in an AB area doesn't necessarily mean that all stop signals through the station limits are also cleared, if they aren't all semaphores. We have one which is almost exactly as described - distant, 3-aspect home, then two semaphore stop signals. The distant will happily come off to a green with a single yellow in the home signal and the next signal ("home 2", as the LM prefer it) at danger, with the full braking distance available. I don't know whether that's the case at Talacre though!

 

[driver_m]

A distant signal 'off' in an AB area doesn't necessarily mean that all stop signals through the station limits are also cleared, if they aren't all semaphores. We have one which is almost exactly as described - distant, 3-aspect home, then two semaphore stop signals. The distant will happily come off to a green with a single yellow in the home signal and the next signal ("home 2", as the LM prefer it) at danger, with the full braking distance available. I don't know whether that's the case at Talacre though!

At Talacre I just can't see how there'd be enough braking distance, however I've been lucky enough to always get greens there. (Cue abuse from ATW drivers ) The one traditional frame box that I've been in cleared its signals by home then section signal and only then would the interlocking allow the distant to be pulled clear.

 

[headshot119]

That shouldn't really happen though should it.. I'd be rather unhappy about passing a green distant in an AB section only to find the home signal showing one yellow at Talacre and expecting to get a voyager doing 85 down to 0 at the section signal, especially when a green distant is supposed to signify that the section is clear throughout. Guessing again but there must be some track approach control at that particular box for that scenario. The NW mainline has strange signalling though even for AB. Can't be many areas that have a Track Circuit Block area within AB areas covering both ends of the boxes' control. (Bangor and Llandudno Jn)

Croes Newydd North Fork is another box with TCB around it but AB on the fringes.

You have similar there where you'll get a green on the distant, yellow on the home, red on the platform starter. Though it's all colour light so slightly different.

Rhyl is another example of the distant not applying to all the signals on that road.

The distant (on the down with the route on the through line) will clear green with the home, RL5 and RL6 off but RL14 on.

But your aspect sequence there is G-G-G-Y-R. And the distances are a bit longer than at talacre.

 

[driver_m]

Croes Newydd North Fork is another box with TCB around it but AB on the fringes.

You have similar there where you'll get a green on the distant, yellow on the home, red on the platform starter. Though it's all colour light so slightly different.

Rhyl is another example of the distant not applying to all the signals on that road.

The distant (on the down with the route on the through line) will clear green with the home, RL5 and RL6 off but RL14 on.

But your aspect sequence there is G-G-G-Y-R. And the distances are a bit longer than at talacre.

Rhyl on the down has an IB section though.

No distants or repeaters at Stockport either, just 4 aspects all the way through yet that's AB too.

 

[edwin_m]

They will clear to green when the relevant home signal lever is revered in the frame.

Are you sure about this? Later posts are expressing doubts about the availability of braking distance between the three-aspect home and the starter, and if this is so the distant should only clear if both stop signals have been cleared.

Like the thought of the lever being "revered". O mighty lever, honour us mere mortals with thine clearance of the distant...

 

[Tomnick]

Again, possibly not the same as Talacre, but we do have a location with exactly the same sequence on the Down. The lever controlling the home signal is red and yellow, but the home signal will only clear (to a green) if the section signal is also clear or (to a yellow) if the berth track circuit is occupied. The distant clears automatically (hence the red and yellow lever), but only of both home and section signals are off. That's all because there's nowhere near sufficient braking distance from the home to the section signal.

The Down section signal really is revered at this location too .

 

[D Foster]

A distant signal 'off' in an AB area doesn't necessarily mean that all stop signals through the station limits are also cleared, if they aren't all semaphores. We have one which is almost exactly as described - distant, 3-aspect home, then two semaphore stop signals. The distant will happily come off to a green with a single yellow in the home signal and the next signal ("home 2", as the LM prefer it) at danger, with the full braking distance available. I don't know whether that's the case at Talacre though!

OH DEAR!!! Have I ever opened a can of worms!!!

As far as I can tell... In the conventional form of Absolute Block - as in all the training material and standard texts I've seen - a Distant (and any combination of inner and outer Distant) - can only be cleared when all the related Stop Signals interlocked in the frame have been cleared.
Perhaps it is worth mentioning that once the Distant(s) been cleared none of the related/interlocked levers can be restored until the Distant lever is back in the frame.

That said... There seem to be a number of apparent variations...
As far as I can see so far these would be (hopefully in chronological order)...
!. The use of Power Signalling (motorised /EP signals with continuous track circuit beteen two Stop Signals) enabled the introduction of Intermediate Block Sections. This is a derivative form of Block Working resulting from Absolute Block Working.
2. In addition to Intermediate Block Working the use of Track Circuits with either Power Worked signals or light signals made Automatic Block Signalling possible.

Both Intermediate Block and Automatic Block have a Distant Signal In Rear of the Stop Signal. That is - the sequence along the track is Automatic Distant, Automatic Home and Intermediate Distant, Intermediate Home.
Both Automatic and Intermediate Distants can be located as Slotted Distants where the Automatic or Intermediate Block Section is short.
Therefore it is possible to get the Absolute Block Section Stop/Section Signal with a slotted Automatic Block Distant under it - and then an Automatic Block Home/Stop with a slotted Intermediate Block Distant under it - before eventually approaching an Intermediate Block Home/Stop Signal.
Because both Auto Block and Intermediate Block Home Signals have their own Distant Signals they are not interlocked with any combination of Absolute Block Stop Signals in Station Limits - which are all interlocked with their own Distant (or Distants).

Just to complicate things... As far as I have seen there will only be one Intermediate Block Section In Advance of an Absolute Block Section Signal but there may be a number of Automatic Block Sections between an AB Section Signal and an IB Home.
In addition an absolute Block Box can have an Intermediate Block Section In Rear. I am still working on figuring out exactly how this was done. I am not aware of any still in use - which no way means that there aren't any...

Meanwhile - back at the list...

3. (As previously hinted at regarding the current GCR). The LNER introduced a variant of conventional Distant application to AB when it introduced Automatic Distants on some of its lines - including at least part of the GCR to London. This non-standard arrangement used (uses) Searchlight signals for at least the first Distant signal approached - this is the automatic signal).

The sequence in this case is - Auto Distant (YGY) on its own, a Distant slotted under the first Stop Signal and then the rest of the Stop Signals.
When all the Stops are On both Distants are Yellow. When the first Stop is cleared the Automatic Distant switches to Double Yellow - the slotted Distant stays at Yellow. When the rest (all) of the Stop Signals are cleared the slottede Distant can be cleared and then the Automatic Distant will switch to a Green. --- I believe that is the correct sequence.

This is a variation of standard Absolute Block. As far as I know it was/is only used on the LNER/by the GCR.

4. In more recent practice something different occurs in AB areas.

A conventional Distant applying to all the Stop Signals of Station Limits is provided. This is interlocked so that it can only be cleared when all the Stop signals have been cleared. Subsequently one or more of the Stop Signals may have been modified so that, instead of only being 2 position Stop Signals, they have 3 aspects (R Y G). In this case the Yellow is not a Distant... It is possible that we could call it a "Repeater" - because it works automatically with the Stop Signal In Advance - when Yellow it is indicating for the Red and when Green it indicates for the Green In Advance.

As far as I can tell these amended 3 aspect Stop Signals (with a "repeater") can occur as any one of the Stop Signals withing Station nLimits - or more than one.
It is definitely the case that there can be a sequence of semaphore, colour light, semaphore.

As far as I know those are the four options in chronological order of appearance.

Oh... Automatic Block, like Intermediate Block, is a derivative of Absolute Block.

If Auto Block fails the Signalman would revert to working with only Intermediate and Absolute Block. If Intermediate Block fails then the SIgnaller reverts to Absolute Block.

Moving to TCB to note an exception... As far as I know there has only ever been one location with TCB signalled with semaphores - this was on the Lincoln line - but I forget its name. When I saw it it looked exactly the same as an Absolute Block arrangement with ordinary two position semaphores. Thinking about it - this seems weird to me... Does anyone know about this for certain please? (I know that I saw it - I was definitely there...

Anyway... I hope that goes some way to explaining both conventional Distant application in Absolute Block and why/how other arrangements can appear.

If anyone knows of any other arrangements I'd love to hear about them.

One of the great things about an interest in signalling is that there is always something new.
--- old post above --- --- new post below ---

A distant signal 'off' in an AB area doesn't necessarily mean that all stop signals through the station limits are also cleared, if they aren't all semaphores. We have one which is almost exactly as described - distant, 3-aspect home, then two semaphore stop signals. The distant will happily come off to a green with a single yellow in the home signal and the next signal ("home 2", as the LM prefer it) at danger, with the full braking distance available. I don't know whether that's the case at Talacre though!

OOPS!! I meant to say that - the arrangement described, with the full braking distance available, sounds like there is an Intermdeiate Block Section. I'm not clear as to whether this is an IB Section In Advance or In Rear.
IB In Advance was far more common than IB In Rear.

The main thing we learn from all this is - the massive importance of "Route Knowledge" with train crew!!!

 

[Railsigns]

As far as I can tell... In the conventional form of Absolute Block - as in all the training material and standard texts I've seen - a Distant (and any combination of inner and outer Distant) - can only be cleared when all the related Stop Signals interlocked in the frame have been cleared.

That's because most descriptions of the Absolute Block system assume (not unreasonably) that semaphore signals are in use. In fact, there is no direct correlation between the method of working (AB/TCB, etc.) and the type of signals in use; therefore it's perfectly possible to use colour lights signals in an AB area and semaphore signals in a TCB area, or a mixture of both.

The crucial point here is that the working of the distant signal is determined not by the block system but by the stop signals that lie beyond it. The reason why, traditionally, a distant signal cannot be cleared until all the relevant stop signals have been cleared is to do with the fact that semaphore stop signals controlled from the same box were usually closely spaced and a semaphore is a two-position signal unable to give distinct 'caution' and 'clear' indications determined by the state of the next stop signal ahead, other than by the application of what used to be called Rule 39(a). If the stop signals are colour lights and they're spaced at full braking distance apart, then there's no reason why the distant signal cannot show a green when the first stop signal is at yellow and the second one is at red. If, however, colour light stop signals are less than braking distance apart, then a semaphore-equivalent aspect sequence must be enforced, so that the distant can't show a green with the second stop signal at red (I suspect this is the case at Talacre).

Consecutive intermediate block sections do exist, by the way.

 

[ComUtoR]

Would the distant pulling off to green be from where if the "signal is cleared slowly" ? My AB is a bit rusty. Been a while since I drove through AB.

I checked my diagrams and they are telling me that the Service braking distance is the bit between the distant and the next stop signal for the "fastest train over that line"

I have also checked and its telling me that if the distant clears green then all "associated stop signals" should be clear

We also have a colour light AB it can get a bit confusing and route knowledge does become key.

 

[driver_m]

Would the distant pulling off to green be from where if the "signal is cleared slowly" ? My AB is a bit rusty. Been a while since I drove through AB.

I checked my diagrams and they are telling me that the Service braking distance is the bit between the distant and the next stop signal for the "fastest train over that line"

I have also checked and its telling me that if the distant clears green then all "associated stop signals" should be clear

We also have a colour light AB it can get a bit confusing and route knowledge does become key.

The signal being cleared 'slowly' is very much now looked at by management as the same as 'approach control' that is to say that it doesn't exist. (Even though it does)

Our rule of thumb is if you don't get any clear distant then it's network rails time and to bumble along slowly ready to stop until the section is clear. Hopefully this thread educates some of our more cynical forum members as to just how important route knowledge actually is, as AB truly needs you to know every inch of track.

 

[Tomnick]

OH DEAR!!! Have I ever opened a can of worms!!!

As far as I can tell... In the conventional form of Absolute Block - as in all the training material and standard texts I've seen - a Distant (and any combination of inner and outer Distant) - can only be cleared when all the related Stop Signals interlocked in the frame have been cleared.
Perhaps it is worth mentioning that once the Distant(s) been cleared none of the related/interlocked levers can be restored until the Distant lever is back in the frame.

The question there is (not that I can add much to Railsigns' excellent reply) what counts as a related signal? As stated, if there is braking distance available from the outermost (i.e. first) home signal to the next stop signal, and that signal is capable of displaying a yellow aspect, then the distant's only "related signal" will usually be the home signal, the green aspect there effectively acting as the distant for the next (and possibly subsequent) stop signals.

That said... There seem to be a number of apparent variations...
As far as I can see so far these would be (hopefully in chronological order)...
!. The use of Power Signalling (motorised /EP signals with continuous track circuit beteen two Stop Signals) enabled the introduction of Intermediate Block Sections. This is a derivative form of Block Working resulting from Absolute Block Working.
2. In addition to Intermediate Block Working the use of Track Circuits with either Power Worked signals or light signals made Automatic Block Signalling possible.

Both Intermediate Block and Automatic Block have a Distant Signal In Rear of the Stop Signal. That is - the sequence along the track is Automatic Distant, Automatic Home and Intermediate Distant, Intermediate Home.

...

Just to complicate things... As far as I have seen there will only be one Intermediate Block Section In Advance of an Absolute Block Section Signal but there may be a number of Automatic Block Sections between an AB Section Signal and an IB Home.
In addition an absolute Block Box can have an Intermediate Block Section In Rear. I am still working on figuring out exactly how this was done. I am not aware of any still in use - which no way means that there aren't any...

I'm not aware of any 'automatic block' sections (presumably referring to automatic signals forming additional sections between the section signal and the IBH, as per some historical arrangements?) that exist to this day, but there are (again as per Railsigns) some places with multiple IB sections, all in advance.

I suppose, in terms of the aspect sequence, there's little difference between the example I gave earlier (with full braking distance available between the outermost home and the next signal) and an IB section in rear - but in my example, it most certainly isn't an IB section (the outermost home signal protects entry to a goods loop).

Just to throw another example into the mix, the aforementioned location has (on the other line), a fairly standard arrangement of semaphore distant, two semaphore stop signals followed by a 3-aspect colour light ("third home"), which then has braking distance available to the section signal (2-aspect colour light), in turn controlling entrance to the IB section with the IBH (and its distant) a little further on. In that case, the distant will come off with just those first three stop signals cleared, a yellow in the third home and the section signal at danger. There's still only the one IB section here though.

Meanwhile - back at the list...

3. (As previously hinted at regarding the current GCR). The LNER introduced a variant of conventional Distant application to AB when it introduced Automatic Distants on some of its lines - including at least part of the GCR to London. This non-standard arrangement used (uses) Searchlight signals for at least the first Distant signal approached - this is the automatic signal).

The sequence in this case is - Auto Distant (YGY) on its own, a Distant slotted under the first Stop Signal and then the rest of the Stop Signals.
When all the Stops are On both Distants are Yellow. When the first Stop is cleared the Automatic Distant switches to Double Yellow - the slotted Distant stays at Yellow. When the rest (all) of the Stop Signals are cleared the slottede Distant can be cleared and then the Automatic Distant will switch to a Green. --- I believe that is the correct sequence.

This is a variation of standard Absolute Block. As far as I know it was/is only used on the LNER/by the GCR.

Absolutely correct on the sequence, but (yet again as stated by Railsigns) it's not a variation on the AB regs but rather just a slightly unusual sequence of signals. The benefits are the ability to get trains inside the clearing point more quickly (if the forward section is still occupied), and the ability to give a positive indication (when the forward section clears as a train is approaching the home signal, having passed the distant at YY) that all subsequent stop signals have been cleared.

4. In more recent practice something different occurs in AB areas.

A conventional Distant applying to all the Stop Signals of Station Limits is provided. This is interlocked so that it can only be cleared when all the Stop signals have been cleared. Subsequently one or more of the Stop Signals may have been modified so that, instead of only being 2 position Stop Signals, they have 3 aspects (R Y G). In this case the Yellow is not a Distant... It is possible that we could call it a "Repeater" - because it works automatically with the Stop Signal In Advance - when Yellow it is indicating for the Red and when Green it indicates for the Green In Advance.

As far as I can tell these amended 3 aspect Stop Signals (with a "repeater") can occur as any one of the Stop Signals withing Station nLimits - or more than one.
It is definitely the case that there can be a sequence of semaphore, colour light, semaphore.

As above really - it's the sequence and type of signals, not the method of signalling, that determines the indications shown.

Moving to TCB to note an exception... As far as I know there has only ever been one location with TCB signalled with semaphores - this was on the Lincoln line - but I forget its name. When I saw it it looked exactly the same as an Absolute Block arrangement with ordinary two position semaphores. Thinking about it - this seems weird to me... Does anyone know about this for certain please? (I know that I saw it - I was definitely there...

It sounds like Swinderby. It was (not sure if it lost one of its semaphores with the Lincoln resignalling?) just like the textbook Absolute Block layout - distant, home and starter in each direction - but works TCB both ways. It's a brilliant illustration of, again, the fact that the method of signalling doesn't really change anything in this context.

OOPS!! I meant to say that - the arrangement described, with the full braking distance available, sounds like there is an Intermdeiate Block Section. I'm not clear as to whether this is an IB Section In Advance or In Rear.
IB In Advance was far more common than IB In Rear.

The main thing we learn from all this is - the massive importance of "Route Knowledge" with train crew!!!

Just as a side note, does anyone know whether any IB sections in rear still remain? I know that they were relatively rare 'back then' anyway.

The signal being cleared 'slowly' is very much now looked at by management as the same as 'approach control' that is to say that it doesn't exist. (Even though it does)

Our rule of thumb is if you don't get any clear distant then it's network rails time and to bumble along slowly ready to stop until the section is clear. Hopefully this thread educates some of our more cynical forum members as to just how important route knowledge actually is, as AB truly needs you to know every inch of track.

Formally, the signal being cleared 'slowly' has absolutely no meaning nowadays (and indeed is impossible in some cases, with a motor-worked semaphore). The crucial thing is ensuring that the train is "quite or nearly at a stand" - I'm not sure exactly how it's worded nowadays, but the principle is the same - at a semaphore stop signal if the next signal can't be cleared. I'd never criticise a driver for taking it easy if he's passed the distant at caution though, even if the home signal is off well before he gets to it (after all, that's a Rule Book requirement too), but I understand that the Driver was found blameless in a SPAD at a section signal where the Signalman had failed to check him properly at the home signal. If only the GCR's "accelerating distant" principle (as described above) was more widespread .

 

[455driver]

only banner repeaters...anyone mention co-actors?

Did you bother to read the top of my post? :roll:

 

[scott118]

Did you bother to read the top of my post? :roll:

yes i did, why what's your issue now?

 

[PaxVobiscum]

...They will clear to green when the relevant home signal lever is revered in the frame.

That must be when the handle of the lever is lovingly polished with a clean cloth by the signalman

I'll get my coat.