Station Layout on single track main line

[Philately]

On the Alnwick to Cornhill/Coldstream line (closed to passengers in 1930) the stations on the west of the track between Whittingham and Coldstream (e.g. Hedgeley and Wooperton) had their single platform faces on the loop, with trap points on the "straight" line.  Those on the east side (like Ilderton) had their platforms on the "straight"line.  When it was built, this section had a double track spec with but a single track actually laid, to allow for the possibility that a line from Newcastle upon Tyne to Edinburgh via Kelso might be built via Ponteland, Belsay, Scotsgap, Rothbury, and Whittingham.  Of course it never happened.

 

At one time, there was a Saturday timetable that had an "autocar"(i.e. Sentinel steam carriage) and a standard Branch train to cross at Hedgeley and, I believe at Mindrum, which only had one platform.  This confounds all our expectations of what's "normal" but gives one lots of operating licence!

 

Richard

[uax6]

Its not quite as easy as just signalling it, you need to know what method of signalling is in use, if its RETB then there will be no signals as such, just stop boards, but if you are using a more conventional system then again you would need to know if it was a local box or a remote box....

 

Andy G

[Dixie Dean]

Its not quite as easy as just signalling it, you need to know what method of signalling is in use, if its RETB then there will be no signals as such, just stop boards, but if you are using a more conventional system then again you would need to know if it was a local box or a remote box....

 

Andy G

 

Thanks Andy G, I think it might be a local box.

[uax6]

Ok, Has it been resignalled as part of an down grade from double track, or has it always been single? What sort of service do you envisage?

 

Andy G

[Dixie Dean]

It's a single track electrified main line, which was always single.  It was electrified and re-signalled 40 years ago but with old boxes controlling colour light signals.  There is one stopping EMU each way each hour with additional DMUs every couple of hours, one express passenger train each way each hour (non stopping) and at least one non stopping freight each hour.  Timber is collected once a day.  It is shunted by a class 03 and collected by an electric loco.  Is that enough information?

 

I realise it is a bit of an oddity, but I like it!

Edited May 7, 2018 by Dixie Dean

[uax6]

Ok. Lets imagine that it was upgraded to Track Circuit Block with direction levers (I can't see any reason off the top of my head that the single lines at each end can't be controlled by direction levers). Now which is the normal route? is the middle road electrified?

 

[Dixie Dean]

The through line, the platform road and the top loop are all electrified.  The timber sidings are not electrified.

[roythebus]

It still seems a most unlikely layout. It would be difficult to have a "busy" single line. This would depend on the section length. to use my local line, Ashford-Rye, it is double from Ashford to Appledore, then single to Rye. The maximum number of trains that can run between Appledore and Rye is 4, as it is a 13 minute section! In practice only 1 per hour usually run in each direction as the next section to Ore is something like a 20 minute section.

 

As for your plan, Wittersham Road on the KESR has a main through road without a platform and a platform on a loop. 

 

On your plan any move onto the single line would require a stop signal to enter the section unless there was an an advanced starter provided to gain access to the single line.

[Dixie Dean]

On your plan any move onto the single line would require a stop signal to enter the section unless there was an an advanced starter provided to gain access to the single line.

 

The single line is entered at both ends from stations with multiple platforms.  So would that requirement be satisfied by a 2 or 3 aspect signal?  If so which?

[PaulRhB]

Usually a two aspect at the entrance to the single line section, red/green, as there will be a distant for the signal at the exit of the single line section. Three aspect only needed if it's at the braking distance for the next signal and that would be a very short single line section

[Dixie Dean]

My grateful thanks to all the contributors so far.  I have now morphed the original diagram into the space I have for this section of the layout. 

 

From what has been outline above, would the below be a suitable signalling arrangement for this section of my layout?

 

 

I presume that there would have to be a two aspect "distant" colour light back from each end of the station in case either of the three aspect signals at each of the loop were showing "stop"?

Edited May 10, 2018 by Dixie Dean

[Dunsignalling]

Yes you do get 3 aspect signals on single lines.  Take Salisbury to Exeter as an example.  The signals giving access to the loops from the single line (eg Tisbury, Gillingham, Chard, Honiton) are 3 aspect with a 2 aspect repeater in the rear. 

And they are approach controlled, obviating the need for trains to stop and be brought into station limits one at a time. 

 

The approach control on the 3-aspect homes is over-ridden when the corresponding section signal is cleared, i.e. when there is no other train to cross.

 

At Honiton, prior to the Basingstoke re-control, the repeaters were actually distants, with their own levers, rather than responding automatically to the state of other signals. 

 

I'm not certain it still applies now there are two separate LED signal heads, but the old up home had feathers for trains entering the up loop. The approach control also functioned to slow trains for the 25mph limit over the points and the time-out was shortened if the down train was already inside and the section signal had been cleared  for the up service to proceed to Chard (more recently, Axminster).

 

Remarkably sophisticated for a simple crossing place, especially given that the difference was only 20 seconds, though it often saved up trains coming to a complete stand at the home signal, so the extra complication was presumably justified.

 

There was a bit of a kerfuffle once when the rather unusual relay that switched the approach control settings failed and the one-and-only spare known to exist was in Scotland. 

 

John

Edited May 14, 2018 by Dunsignalling

[Joseph_Pestell]

It's a single track electrified main line, which was always single.  It was electrified and re-signalled 40 years ago but with old boxes controlling colour light signals.  There is one stopping EMU each way each hour with additional DMUs every couple of hours, one express passenger train each way each hour (non stopping) and at least one non stopping freight each hour.  Timber is collected once a day.  It is shunted by a class 03 and collected by an electric loco.  Is that enough information?

 

I realise it is a bit of an oddity, but I like it!

 

Rare enough in this country that we even manage to electrify a busy double-track railway. What you are suggesting is therefore definitely a bit of an oddity.

[Dunsignalling]

My grateful thanks to all the contributors so far.  I have now morphed the original diagram into the space I have for this section of the layout. 

 

From what has been outline above, would the below be a suitable signalling arrangement for this section of my layout?

 

station.png

 

I presume that there would have to be a two aspect "distant" colour light back from each end of the station in case either of the three aspect signals at each of the loop were showing "stop"?

Your proposed layout suggests an intensive pattern of freight working that will sometimes require two freights to pass, with neither using the platform road, otherwise there would be no requirement for a second loop. 

 

It's therefore likely that only one would need, or justify the cost of, bi-directional signalling that would only come into its own if three trains were in play at once. It's actually rather difficult and time-consuming to arrange that on a secondary railway with longish single line sections, which most have, so it's an unlikely scenario.

 

Continuing the Salisbury-Exeter example, some section running times are getting on for 20 minutes, and that's with a passenger-only service and a 85mph line speed over most of the route. Adding a second loop and considering the time it would take to get three trains in and out, two probably limited to 60mph, one of them would be likely to be held for up to half an hour. 

 

On the odd occasion when three trains were in play at Honiton, usually involving WR diversions in addition to the base service or during service recovery, the method was, once the first of the two trains travelling in the same direction was inside, to accept the second. Once the movement in the opposite direction arrived the first could depart and the second would make the cross when it arrived. One train thus had to wait for as long as it took, though sometimes the second train it was crossing would already be waiting at the home signal. Some signals at Honiton were repositioned in the recontrol process, and such "double crosses" are now only permissible (and practical) for two up trains crossing one down.  

 

Your comment about repeaters (automatic) or distant signals (controlled) is correct.

 

John

Edited May 10, 2018 by Dunsignalling

[Dixie Dean]

I fully realise that my layout isn't very prototypical, but I would like to get the signalling as correct as possible, despite the unusual layout. 

 

The loop on the other side from the platform is for shunting and running around the timber train.  I also added two small shunting stubs in which freight wagons could be stood for loading/unloading as if wagon load was still happening.

 

I wasn't thinking of two trains passing a third.  In fact, neither loop is long enough for passing freights to set into.  I did wonder if it would be a good idea to increase the length of the loop opposite the platform to allow for freight trains to pass.

 

Are you implying that if it's not for passing and only for running around it is unnecessary?  Please clarify.  Perhaps you mean I could use the platform road to run around?  I put full signalling on it to provide for the timber train to enter the main line.  Is this unnecessary?

[roythebus]

You will also need a signal to control movements into and out of the goods loop at the top of the diagram. A subsidiary signal under the main aspect, probably with a small box with a letter indicating which route was set, proceed as far as the line is clear! I would suggest P=platform, M=main, L=loop.

 

You will also need subsidiary signals to get from the platform and goods loop into the spur sidings.

Edited May 12, 2018 by roythebus

[Dixie Dean]

Thanks for  that roythebus.  I missed that completely.  I will amend the diagram accordingly.

 

Everyone, please bear with me whilst I consider whether to lengthen the platform loop at either end so that if there is no passenger train in the station 2 freights would be able to pass each other if necessary, and a big thanks to everyone for their contributions so far.  They are much appreciated.

Edited May 12, 2018 by Dixie Dean

[Ronnie MB]

Could the layout be justified by a backstory about this being the former junction of a now lifted branch?

[009 micro modeller]

I noticed while on a train to Scarborough today that Malton seems to have an odd single platform layout. There are two tracks either side of the station and both are through lines but all stopping trains (are there any that don't stop?) use the single platform, crossing over if necessary. Also there are three dead end sidings on the non platform side, I'm not sure what for though.

[Dixie Dean]

Could the layout be justified by a backstory about this being the former junction of a now lifted branch?

 

Not very likely, I'm afraid, as the line runs along the side of a valley, with a drop off on the shunting loop side.