Trivia: Signals That Never Show Green

[Doomotron]

Are there any signals on the network that for some reason cannot show green (not including signals that don't actually have a green aspect, obviously)? As in signals that technically are capable of showing a green aspect but never do in real life.

 

[Ianno87]

The signal that protects Shepreth Branch Jn approaching from Cambridge cannot show green for a train diverging towards Royston, even if the next signal is green. The least restrictive aspect it can show for this direction is Double Yellow.

 

[Peter Mugridge]

I would have thought that just about every penultimate signal on any terminating line would only be able to show danger and caution - but presumably that would be excluded by your "not capable of showing green" specification?

 

[TBSchenker]

Blackpool No 1 signalbox had a 3-aspect colour light home signal (BN1.33) that has its green aspect disconnected several years ago . It had its own colour light distant that would show green (BN1.33R)

The reason being the relatively short section to Blackpool North No 2s home signal, and the fact that BN1.33 was also the distant signal for Blackpool North No2s home signal.

BN1.33 used to be able to show green when both of Blackpool North No2s home signals were OFF and the route set into the station. Some standard changed and it was no longer acceptable to offer a green colour light offering a 70mph approach with a short distance to a 15mph restriction (could it be TPWS introduction?).

Thereafter it was restricted to just displaying red and yellow. If Blackpool No 2 cleared it's signals then BN1.33 would immediately show a yellow aspect, with BN1.33R displaying a green. If Blackpool North No2s had its first homesignal ON then BN1.33 became approach controlled and cleared to a yellow once a train got to the AWS magnet. This also kept BN1.33R at caution.

 

[bionic]

Pretty much every signal between Hither Green and London Bridge!

 

[driver9000]

The Up starting signal (PN106) for platform 1 at Preston will never display a green aspect.

 

[krus_aragon]

Signal LJ68, on the Up Main at Conwy, is a one-aspect signal: it can only show red!

The Up Main is bidirectional between Llandudno Junction and Conwy, and LJ68, just beyond Conwy station, marks the limit. Back when Conwy Valley services interworked with Holyhead stoppers, there used to be some occasional Llandudno-Conwy services too (e.g. one mid-morning shuttle in the 1994 timetable on my shelf). I've got no idea when it was last used, though.

 

[Mag_seven]

Signal LJ68, on the Up Main at Conwy, is a one-aspect signal: it can only show red!

Doesn't satisfy the OP criteria (as it doesn't actually have a green aspect), but for reference these "fixed red" signals generally are used at the end of a stretch of bi directional running where a reversal is required. They stop the driver from continuing on down stretch of track that is no longer signalled for bi-directional running.

 

[krus_aragon]

Doesn't satisfy the OP criteria (as it doesn't actually have a green aspect), but for reference these "fixed red" signals generally are used at the end of a stretch of bi directional running where a reversal is required. They stop the driver from continuing on down stretch of track that is no longer signalled for bi-directional running.

Apologies, I seem to have glazed over the portion in brackets.

 

[Eccles1983]

There are loads.

I can think of 3 off the top of my head. The one controlling entry into Southport from meols cop. And on the up fast leaving man Vic to Salford. (e line)
The down slow before the down good loop at Piccadilly/longsight.

 

[Tim M]

I would have thought that just about every penultimate signal on any terminating line would only be able to show danger and caution - but presumably that would be excluded by your "not capable of showing green" specification?

The principle of only showing a yellow reading up to a terminal platform was used at Victoria Eastern during Resignalling in about 1980. To ensure uniformity (particularly for drivers) the equivalent signals on the approach to Victoria Central (resignalled soon after) were altered on the same weekend as were those at Waterloo.

 

[furnessvale]

A fixed distant is quite a common concept in semaphore signalled areas.

Although I cannot quote any examples, I see no reason why this is not duplicated in colour light signalling.

 

[Llama]

MP657R distant signal between Hall I'Th Wood and Bromley Cross. I would be surprised if it has been cleared this decade (I saw it cleared last decade, when an empty stock was booked to run, maybe twice).

Its related signal, MP657, sits on the Blackburn end of Bromley Cross station protecting entrance to the single line from Bromley Cross to Darwen. The reason why it is so seldom cleared is because of the foot crossing beyond Bromley Cross station which has gates interlocked with the signalling. The crossing keeper in Bromley Cross gate box keeps the crossing open as long as is possible, often to the detriment of the punctuality of trains.

 

[bramling]

Are there any signals on the network that for some reason cannot show green (not including signals that don't actually have a green aspect, obviously)?

How about the signals approaching Drayton Park? My understanding is both starting signals at Drayton Park platform have a timing section on them, presumably to ensure trains stop to carry out the AC/DC changeover. This would mean the preceding signals can never show better than yellow.

There’s a few red/yellow/green draw-up signals on LU that rarely if ever show green for various reasons, and plenty of repeater signals across the combine which are yellow only, although in many cases these are fixed. LU even have things like dummy junction indicators to present consistency to drivers!

 

[TBSchenker]

There are loads.

I can think of 3 off the top of my head. The one controlling entry into Southport from meols cop. And on the up fast leaving man Vic to Salford. (e line)
The down slow before the down good loop at Piccadilly/longsight.

Down slow into down goods at Longsight only shows red/yellow. It doesn't have a green aspect to show .

 

[ComUtoR]

A fixed distant is quite a common concept in semaphore signalled areas.

Although I cannot quote any examples, I see no reason why this is not duplicated in colour light signalling.

SIMBIDS have a fixed distant.

 

[Llama]

There are loads.

I can think of 3 off the top of my head. The one controlling entry into Southport from meols cop. And on the up fast leaving man Vic to Salford. (e line)
The down slow before the down good loop at Piccadilly/longsight.

Of those signals, none is capable of showing a green aspect, there are plenty of similar signals but I think the OP was after signals that are capable of displaying a green but never do.

 

[Y Ddraig Coch]

Doesn't satisfy the OP criteria (as it doesn't actually have a green aspect), but for reference these "fixed red" signals generally are used at the end of a stretch of bi directional running where a reversal is required. They stop the driver from continuing on down stretch of track that is no longer signalled for bi-directional running.

It actually does have a green aspect or possibly a yellow at least, I don't know which as it hasn't ever been used. Only used to stop any mistakes as the train ran wrong road form Llandudno Junction to Conwy as mentioned up thread for the Sunday Llandudno Junction to Conwy Shuttles in the early 90's.

 

[edwin_m]

The principle of only showing a yellow reading up to a terminal platform was used at Victoria Eastern during Resignalling in about 1980. To ensure uniformity (particularly for drivers) the equivalent signals on the approach to Victoria Central (resignalled soon after) were altered on the same weekend as were those at Waterloo.

I believe this was a response to the Moorgate collision on (then) Underground infrastructure. The standards were changed so a signal reading to a buffer stop can never show anything less restrictive than single yellow, so in four-aspect areas the signal before that can't show green either. This could have been implemented by changing the aspect controls and leaving the signal unchanged, but I would think the affected aspects would have been blanked out or removed entirely.

 

[tsr]

Some of the signals on the West London Line will never normally show green except for freight trains running both bidirectionally and on routes not used for passenger traffic, eg. Up the Down line at Imperial Wharf. And, conversely, on approaching Kensington Olympia going Down the Up line, a driver is unlikely to ever see a green unless they are running a passenger train bidirectionally into the platform.

 

[LAX54]

CO 326 and CO328 on the Up Main and Up Lowestoft at Ipswich, if a route is set via P2 all the way through, they will stay a double yellow, due to the fact that CO308 will not clear up to a green until berth track occupied in P2.
CO326 WILL show a green if routed through Middle Toad.

In the same area, sort of in reverse... CO286 is an Auto signal, but this will stay at red, until the signal (292 or 294) in rear is cleared up to it.

 

[sw1ller]

It actually does have a green aspect or possibly a yellow at least, I don't know which as it hasn't ever been used. Only used to stop any mistakes as the train ran wrong road form Llandudno Junction to Conwy as mentioned up thread for the Sunday Llandudno Junction to Conwy Shuttles in the early 90's.

According to my route map, it only has a fixed red, I don’t recall if there’s a 2nd lens fitted but if it does, it shouldn’t work. That’s if, of course, my map from 12/11/2026, that’s still showing semiphore signals at Talacre, is correct!

 

[Tomnick]

It actually does have a green aspect or possibly a yellow at least, I don't know which as it hasn't ever been used. Only used to stop any mistakes as the train ran wrong road form Llandudno Junction to Conwy as mentioned up thread for the Sunday Llandudno Junction to Conwy Shuttles in the early 90's.

It can’t show anything other than red - there’s no signal in advance for it to read to, and indeed it’d take you back into an absolute block section.

 

[OuterDistant]

Travelling to Stoke from the Derby direction, I don't think the Foley Crossing starter (FY.33, a 3 aspect colour light) ever shows green.

It's the last signal before the one protecting Stoke Junction (SOT.457) which has a 15 mph restriction, and I think is approach released. I've only ever seen FY.33 at yellow.

 

[westcoaster]

WH496 Bedford P3 heading south only shows red or single yellow. All other signals are 4 aspect except this one ( and the 3 aspect on P1a for the Marston vale line).

Any signal into a terminating bay.

 

[Y Ddraig Coch]

It can’t show anything other than red - there’s no signal in advance for it to read to, and indeed it’d take you back into an absolute block section.

The point I was making was it isn't a single aspect signal there is another light above the red. Used or not it is there.

 

[Burgerstahl]

Travelling to Stoke from the Derby direction, I don't think the Foley Crossing starter (FY.33, a 3 aspect colour light) ever shows green.

It's the last signal before the one protecting Stoke Junction (SOT.457) which has a 15 mph restriction, and I think is approach released. I've only ever seen FY.33 at yellow.

It can, and does, show green. There is a 15mph warning board and associated aws magnet for the 15 psr over Stoke junction.

 

[Deepgreen]

The OP wanted to know (I believe, from reading the one-line post) about signals which have a green aspect physically fitted but which never display it. 90% of the posts so far seem to have ignored this simple request.

 

[tsr]

The OP wanted to know (I believe, from reading the one-line post) about signals which have a green aspect physically fitted but which never display it. 90% of the posts so far seem to have ignored this simple request.

BN133 and PN106 seem to fit those criteria and there are other interesting examples which are related. I'd say it's a pretty good investigative thread so far.

Perhaps you could post a constructive example if you are not satisfied with the quality of the material, rather than just complaining...

 

[Ianno87]

The OP wanted to know (I believe, from reading the one-line post) about signals which have a green aspect physically fitted but which never display it. 90% of the posts so far seem to have ignored this simple request.

Never* display it or cannot display it? Important distinction.

If latter, there would usually be no green lamp fitted full stop.

*Signals will always be able to display in certain conditions, e.g. testing or when traffic levels are low.