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London Bridge ASC

Introduction

London Bridge ASC (Area Signalling Centre) is a large power signalbox dating from the mid 1970s located just to the south east of London Bridge station in London. It controls the lines from Charing Cross, Blackfriars (exclusive), and Cannon Street, through to Woolwich, Grove Park, Hayes, Bromley North, Lee, Eltham, Crystal Palace (exclusive), Norwood Junction (exclusive), and Peckham Rye. One of its distinctive features is the thick trunk of eleven running lines from London Bridge to Spa Road - your author spent many a happy evening rush hour on the end of the platforms just watching the constant parade of trains traversing these lines, whilst devouring a Casey Jones milkshake!

The signalbox is a two storey building arranged in the usual manner of operating floor on the top floor and interlocking (relay) room on the lower floor. The interlocking is mostly Westpac though some SSI has taken over places like Cannon Street and parts of Hither Green. The operating floor consists of a larger indication panel and separate control desk on the north side of the building, along with a smaller indication panel and similarly separate control desk on the south side of the building, arranged such that the two panels face toward each other. A raised platform in the centre accommodates supervisory and support staff.

The London Bridge ASC simulation is large and very busy. With ARS provided it is possible for one player to supervise the whole layout, but that player does need to scroll back and forth constantly to watch for regulation issues. In real life there are nine signallers operating this area at once, and with the simulation in full manual mode most of those signallers will be very busy. It is not unusual to have 80 trains in the simulation at any one time.

In real life, signallers usually start on part of panel 4 or part of panel 8. In each case they would normally take one end of the panel with a qualified signaller operating the other end and supervising the new signaller. After a few days the new signaller may take the opposite end of the same panel, or take over the whole panel - again, with supervision.

Please note that due to the size and complexity of the simulation, coupled with the large number of trains in the standard weekday timetable, means that high speed running may require a high specification gaming machine. Normal to 2-3x speed is perfectly okay on slower machines. Bear in mind the volatility of internet connections when hosting and running at a higher speed than normal.

Although the introduction above is written in the present tense, the signalbox is slowly disappearing. See the closing words in this article for the situation moving forward.

Eras

The simulation contains two eras which roughly cover the years 2000-2009 and 2010 to 2014. The later era’s main changes are the addition of Old Kent Road Junction and changes at New Cross Gate, both for the East London Line connections, and doubling of the Tanners Hill line near Lewisham.

ARS

The simulation comes with optional ARS which will set nearly all routes, except into fully occupied platforms and some shunt routes. The real box does not have ARS, nor any ACI.

Performance of ARS is reasonably good, given the complexity of the area and number of trains at any one time. Don’t expect it to be perfect as it is not, nor is it meant to be. Some multi-train conflicts are best solved by the human brain based on knowledge and experience - something very difficult to achieve in computers.

Things to watch for are joining and platform sharing moves, late or early running (typically 5 minutes or more), Peckham Rye, Hither Green, and occasionally Lewisham.

Generally if ARS is holding a train for another that is late, it may be better to let the on-time one run first, even if out of booked order. However, you do need to check that that won’t cause further delays down the line.

Train Describer

Stepping is per real life. In bay platforms all descriptions step into the last arrival berth (buffers end). All departures step out from the signal end (departure) berth. There is no stepping from the arrival into the departure berth.

Except in Easy mode, all trains from Hither Green and Grove Park need to be manually described - the shunter will advise of the description (explained elsewhere). In easy and standard modes, descriptions will step through the washer.

Many shunt signals have associated train description berths and stepping, though some do not. These include L1302, L1305, L1382, L1070, and L1068.

Simulation Options

“Easy” mode adds help which does not exist in the real life signalbox.

General Comments

Platform and Loop Lengths

See Platform and Loop Lengths

Telephone Calls

Due to the density of services in the London area, drivers in real life are asked not to call the signaller if they are stopped at a red signal and can see a train crossing in front of them. Even without a train, they are still asked not to call for 5 minutes instead of the usual 2. The London area is defined as St. John’s, North Kent East Junction, and South Bermondsey Junction to the London termini. Outside of this area the standard 2 minute rule applies.

This does have the side effect of causing even more congestion if you are not paying attention. Always scan your area to check for any trains approaching red signals; don’t wait for a call to tell you this.

Bay Platforms

All of the bay platforms in the London Bridge ASC area have three classes of route and operate in the same way. Each of the bay platforms consists of two track circuits, the length of which varies depending on the location. The main route (a single yellow aspect) requires the entire platform clear (both track circuits). The call-on route (a calling-on aspect) requires the buffer end track circuit occupied with the signal end track circuit clear. The permissive route (also a calling-on aspect - no differentiation for the driver) can be used when both tracks are occupied.

The main route is set by clicking on the entrance signal and the grey triangle exit. The calling-on route is also set this way - the interlocking decides whether a main or call-on should be used.

For the permissive route, the berth track circuit before the last signal into the platform must be occupied for a time. In the case of Charing Cross, Cannon Street, and London Bridge this time is around 10-15 seconds depending on the signal. For Hayes and Bromley North the time is 60 seconds. Once the timeout has elapsed, the route can be set from the entrance signal to the WHITE exit arrow.

There is no Lime Street Control anywhere in the area. It is therefore very easy to put a train into a platform that is not long enough. There is even more of a risk for the permissive routes because the remaining platform length may only be 2-3 cars long. For this reason, ARS has been configured to NOT set permissive routes. Check carefully when setting manually!

Closing Up Controls

Some signals have what are called closing up controls. These hold a signal at danger when the next signal is also at danger because of a train ahead in a station, even though this signal could potentially show a proceed aspect. When the train ahead starts to move out of the platform, this signal steps up to single yellow. This allows the next train to approach the platform at a higher speed than if it was creeping forward on single yellows. It means a second train can enter the station around 20-30 seconds sooner, which is a significant saving on headways of 120-180 seconds.

Closing up controls are fitted on signals L91, L93, L67 west of London Bridge; L116, L118, L60, L62, L120, L122 (to L112 only) east of London Bridge, and L251/L253 towards L445 at Lewisham.

Signals L95/97/89/99/101/108/110/112 work automatically until cancelled manually. However, this only applies if the appropriate ARS subarea is disabled. If the route is set and the appropriate ARS subarea is switched on, the route will remain set until cancelled manually or a train passes through the route correctly.

There are some automatic warner routes at other places but these are not considered closing up controls.

Interdivisional Exits

Panels 3 and 9 interface with each other three times between London Bridge and Blue Anchor. All three interfaces work the same way. In this description the “sender” is the signaller that wants to send a train to the other panel, while the “receiver” is the signaller that receives the train.

When the sender wants to send a train to the other panel, the appropriate green “advance request to” should be left-clicked. This generates an alarm on the receiver’s panel, warning them that a train is approaching. When the receiver is ready to take the train, a route is set from the red triangle on the receiver’s side of the green panel boundary to the appropriate exit signal. Note that this locks up points on the sender’s side so the sender should not offer the train unless he is prepared to lose control of those points. The receiver can consider the “advance request” as a go-ahead to take control.

Once the route from the red triangle has been set, the sender can now set up his half of the route. This is set from the appropriate entry signal to the grey exit triangle adjacent to the green panel boundary.

Signals will now show proceed, if appropriate. Either signaller can take back their half of the route, restoring the entry signal to danger.

ARS will request both halves of the route; the second half first. If a second half is set manually, ARS may call the first half even if no train is approaching.

The interdivisional exits are not the same as those employed at Waterloo (Wimbledon simulation).

Panels

Panel 1

The Blackfriars Spur and Metropolitan Reversible are dually controlled by both Panel 1 and Panel 2. Each has the same set of controls with the exception of the Request to Victoria which only Panel 2 has. Phone calls from signals in this area will go to Panel 2 for this reason.

Beware of the very short signal sections on this panel. It is not unusual for a long train to span two or even three signal sections. This can result in a Mexican Standoff so route carefully.

Due to the risk of gapping a train when standing at L13, signallers should not bring trains to a stand here. The ARS has been configured to not set route to L13 unless the route beyond is free to set.

ARS will not route up to signal L12 while any part of a route is set from platform 3 to L13. This is to prevent the two trains potentially blocking each other’s exit beyond L12 and L19 (to L23) which happens with longer trains.

Up trains will leave Waterloo East as soon as they have completed platform duties, per real life. The density of services means it is important to get the trains away as quick as possible - and passengers don’t really care which train they are boarding for one stop.

The distance between a block joint and the next signal can be very short due to the tight pointwork. Therefore it may appear that a train has stopped too short of the signal. Bear in mind that signaller’s screens/panels are never to scale so the train may well be within 10m of the signal yet still on the previous track circuit. This can happen at L13 (from platform 3), L18, and L20.

Blackfriars acceptance controls - see Panel 2.

Terminus platforms - see the general comment about bay platforms.

Panel 2

Do not bring a train to a stand at signal L73 due to the risk of gapping (no electrical shoes in contact with the 3rd rail due to the pointwork). ARS has been configured to not route to this signal unless the route from L73 to L79 is also available. - this has the side effect of preventing trains being automatically routed to L81, though few trains are timetabled that way.

The Blackfriars Spur and Metropolitan Reversible are dually controlled by both Panel 1 and Panel 2. Each has the same set of controls with the exception of the Request to Victoria which only Panel 2 has. Phone calls from signals in this area will go to Panel 2 for this reason.

Beware of the very short signal sections on this panel. It is not unusual for a long train to span two or even three signal sections. This can result in a Mexican Standoff so route carefully.

Points 709 are locked with a route set from L80 signal. You do not want to set a route from L80 after a train has passed from L73 to L79 as points 709 will be in the wrong position. Then cancelling L80 results in a 2 minute timeout as it sees the train receding from L79. It is therefore better to wait until route is set up to L80 before setting a route beyond it. This is a common “gotcha” in real life.

Closing up controls on L91/L67 signals - see the general comment about closing up controls.

The distance between a block joint and the next signal can be very short due to the tight pointwork. Therefore it may appear that a train has stopped too short of the signal. Bear in mind that signaller’s screens/panels are never to scale so the train may well be within 10m of the signal yet still on the previous track circuit. This can happen at L72, L73, L74, L75, L79, L80, and L85.

The connection to Victoria South Eastern on the Blackfriars spur is simple for passenger trains. Down trains need no special mention. Up passenger trains use the Up Blackfriars Spur and do not require a slot from L44 to VS376. Up empty passenger trains, on the other hand, should be coordinated with Victoria by left-clicking on the Request to Victoria control. They will respond with either an acceptance on the Up Blackfriars Spur (44(M)) or the Down Blackfriars Spur (44(S)). For 44(M) set the route from L44 to L376; for 44(S) set the route from L44 to VS674. For the latter, a further indication (Victoria control on 44(S)) will light when the conditions allow L44 to show a proceed shunt indication.

ARS will not route to L76 unless the country end track in platform 7 is clear at Cannon Street. This allows for platform alterations but does mean manually routing through L76 if there is a genuine platform share or join in platform 7.

Terminus platforms - see the general comment about bay platforms.

Panel 3

Closing up controls on L93/L116/L118/L60/L62/L120/L122 signals (except to L102) - see the general comment about closing up controls.

Signal L128 when routed to L118 will stay at danger unless L118 is off. This is to prevent a train straddling and blocking the station throat.

Line 2 is fully reversible, split into two sections at Spa Road, and may be used in one direction or the other at any time of day. However, timetables lean towards London-bound in the AM peak and outbound in the PM peak.

Signals L152 and L154 have misreading controls applied. Each can have a route set but will only show proceed if a route is set towards them from L160, or their berth track is occupied.

Panel 4

The warner routes to signals L207 and L209 were disconnected in the 1970s due to a SPAD incident and have never been reinstated.

Non-stop trains between North Kent East Junction and Charlton (exclusive) may be routed via either Greenwich or Lewisham without penalty. Note that the Lewisham route will take a couple of minutes longer however.

Non-stop trains between New Cross (inclusive) and Lewisham (exclusive) may take either the fast lines via Tanners Hill or the slow lines via St. John’s. However, it would be prudent to discuss with your colleague on Panel 5 before routing anything in a way not timetabled.

Panel 5

Signals L433 and L434 protect Charlton Lane crossing, which has its own crossing keeper. An indication on the screen above the crossing shows whether the crossing keeper has given the slot. No special action needs to take place, except setting routes early enough for the keeper to get the gates closed without delaying trains.

Signals NK101 and L444 near Woolwich Arsenal have dual replacement facilities with the adjacent signalbox (North Kent at Ashford IECC).

Closing up controls on L251 and L253 to L445 - see the general comment about closing up controls.

Non-stop trains between North Kent East Junction and Charlton (exclusive) may be routed via either Greenwich or Lewisham without penalty. Note that the Lewisham route will take a couple of minutes longer however.

Non-stop trains between New Cross (inclusive) and Lewisham (exclusive) may take either the fast lines via Tanners Hill or the slow lines via St. John’s. However, it would be prudent to discuss with your colleague on Panel 3 before routing anything in a way not timetabled.

Trains from Angerstein Wharf will be phone for permission to occupy the single line to Angerstein Junction. After the train enters, it will stop at the stop board by the FP (footpath) crossing and phone you for permission to proceed to signal L425. The identity of th stop board here is STOPA1.

You should phone Angerstein to advise them of a train going that way. The train will stop briefly at the FP crossing before exiting the simulation. Beyond ensuring the line is clear, there are no special controls in place.

The Angerstein branch is fairly short, under a mile, with the last nearly quarter mile from the FP crossing to signal L425 track circuited.

The line towards Nunhead is initially quite steep. It is therefore better to give freight trains a run up by holding them outside Lewisham until the road is clear to VS458. In the opposite direction, L249 is approach controlled if L253 is at red, in order to control the speed of descending trains.

The straight/fast route at Blackheath is towards Charlton; similarly the straight route from Charlton is towards Blackheath. Both other routes are approach controlled from red.

Panel 6

The Hayes auto working relieves the signaller of simple moves at this station by automatically routing trains into and out of platform 2. The ARS subarea, if ARS is enabled for the simulation, must be switched off to use this feature. Left-click on the white “No.2 platform working” circle to enable auto routesetting. The interlocking will set route into platform 2, if free. With a train in platform 2 for 30 seconds, it will automatically set route back out of the station. Right-click on the white roundel to disable auto working.

When no platform number is present in the timetable for Hayes, by default the ARS will use platform 2. However, usual real life practice is to switch to platform 1 a few hours a day to ensure the rails do not rust over.

When Victoria wants to send you a train at Beckenham Junction, they will operate the “Request from Victoria” slot. To grant the slot, set a route from virtual signal 384 to L376. This then allows Victoria to set one of three routes up to your L376 signal. The slot can be cancelled by right-clicking on virtual signal 384.

Terminus platforms - see the general comment about bay platforms.

Panel 7

The track circuits to the right of L1323 and L1321 are geographically parallel and too close to each other to permit occupancy of one while a route is set through the other. The signal protecting the route will be held at danger until the opposing track circuit is clear.

Signals L1315/1317 won’t show proceed until L309 is showing proceed.

Route L306 to L300 is a shunt route only. Do not route passenger trains this way, nor L295 to L301 (which is a main route but nonetheless not for passenger trains).

The washer is operated locally. The Free lights indicate if you can send a train into that particular washer road. The grey/white arrows indicate when the washer operator has set a route through the washer from that particular road. The corresponding Free indicator out the other end will extinguish, showing on to which road the train will exit the washer.

The Bromley North auto working relieves the signaller of simple moves at this station uby automatically routing trains into and out of platform 2. The ARS subarea, if ARS is enabled for the simulation, must be switched off to use this feature. Left-click on the white “No.2 platform working” circle to enable auto routesetting. The interlocking will set route into platform 2, if free. With a train in platform 2 for 30 seconds, it will automatically set route back out of the station. Right-click on the white roundel to disable auto working.

When no platform number is present in the timetable for Bromley North, by default the ARS will use platform 2. However, usual real life practice is to switch to platform 1 a few hours a day to ensure the rails do not rust over.

Terminus platforms - see the general comment about bay platforms.

The track circuits approaching signal L312 is fairly short. Be careful when crossing trains over as anything 6-cars or more is likely to block the Down Fast if held at L312.

It may be better to hold a second train back if approaching the washer from the same direction as a first train, lest you block their exit from the other direction. There is no restriction: just a technique to consider.

From Parks Bridge Junction to Chislehurst Tunnels the line rises at around 1 in 120 on average. This poses a challenge to heavier freight trains so regulate knowing that down trains may take a little longer than expected.

Due to the triangle at Lee Spur, trains on the Lee Spur connection (L345/L299) may show the opposite direction to that expected (i.e. Up on the Down line and vice versa). This is nothing to worry about and just a quirk of small triangular junctions.

Panel 8

From Denmark Hill to Peckham Rye there is a slot control. Set a route from virtual signal VS441 to your signal L636 to grant the main route, but this will lock up the trailing point coming in from the Up Portsmouth line. You can also set the slot for the warner route by using the yellow triangle instead which will not lock the point. Either route can be left in auto. Note that virtual signal shows the state of the slot (red for on; white for off), *not* the aspect of the signal VS441. The slot will show off while the train is still in the route. Giving either the main or the reduced route slot does not affect Victoria’s ability to route trains any way over Crofton Road Junction.

Be aware of stopping and non-stopping trains for Brockley, Anerley, etc.

Honor Oak Park is indeed spelt that way. It is not entirely clear how this came about: one theory is that the oak tree itself dates back to the time when -our endings instead of -or endings were not yet standard for British English.

Panel 9

It is very easy to route a train from L508 to L498 and then discover there are no platforms for it, and no way out for any trains in platforms 14 to 16. ARS has been configured to not set this route unless the country end track circuit of any of platforms 13 to 16 is clear. This may prevent a valid joining or platform sharing move from taking place automatically.

An added precaution is ARS will not set to L500 if platforms 14 to 16 country end track circuits are all occupied. Trains will thus be held at L508 and will need to be manually signalled onwards if they are due to join a train already in 14-16. Holding trains back at L508 gives more choices for replatforming if necessary.

There is a similar, albeit reduced risk, for other inbound signals blocking outbound moves at London Bridge Low Level.

The distance between a block joint and the next signal can be very short due to the tight pointwork. Therefore it may appear that a train has stopped too short of the signal. Bear in mind that signaller’s screens/panels are never to scale so the train may well be within 10m of the signal yet still on the previous track circuit. This can happen at L501, L503, and L505.

The ground frame at London Bridge Low Level is not in use in the simulation.

Terminus platforms - see the general comment about bay platforms.

Interlocking Codes

The same 2/3-letter interlocking codes used in real life have been used in the simulation:

AN - Angerstein, Charlton, and Blackheath

BY - Bromley North

CX - Charing Cross to Waterloo East

CS - Cannon Street to London Bridge platforms 1-3

EE - Elmers End

FH - Forest Hill and Sydenham

HG - Hither Green to Grove Park

HS - Hayes

KR - Old Kent Road

LC - London Bridge Central: London Bridge Low Level to Blue Anchor

LE - London Bridge Eastern: Metropolitan Junction to Blue Anchor

NB - New Beckenham

NE - North Kent East Junction to New Cross

NG - New Cross Gate, Bricklayers Arms, and South Bermondsey

PB - Parks Bridge: Tanners Hill, Lewisham, Parks Bridge Junction

PR - Peckham Rye

Timetabling

Sectional Appendices and Rules of the Plan from 2000 to 2014 should be referred to for timetabling knowledge. Note that from around 2015 onwards London Bridge Low Level was starting to be resignalled and schedules changed significantly with new junctions and line codes, and is thus not supported in this simulation.

Chaining

London Bridge can be chained to Victoria Central and Victoria South Eastern. There are multiple connections to each of these.

Potential future sims may exist which would be Croydon, North Kent, and Ashford IECC.

Always ensure you have the latest versions of each sim when chaining.

Multiplayer

The following are suggestions based on real world workings and simulation testing.

New users should be started on either Panel 4 or Panel 8. Charing Cross (Panel 1) is the more straightforward of the terminus panels for intermediate users. The most difficult is Hither Green (Panel 7) as that involves the depot, calls, and freight trains.

If you are short of players, you can use ARS on the unmanned panels, ensuring somebody is supervising it frequently.

Panels can be combined, whether with or without ARS. Panels can be combined as follows:

Panels 1 and 2

Panels 3 and 4

Panels 5 and 6

Panels 8 and 9

which leaves Panel 7 as a solo panel. With one less player the combination could be:

Panels 1, 2, and 3

Panels 4, 5, and 6

Panels 8 and 9

Again, leaving Panel 7 as a solo panel.

Included 2009 Timetable

Included 2009 Timetable

Signal Number Plan

London Bridge 2000-2009 Signal Number Plan
London Bridge 2010 Signal Number Plan

Signal Box Prefix Codes

Code Box
AD Ashford ASC*
EL East London Line SCC
NK Ashford ASC (North Kent Panel)*
T Three Bridges*
VC Victoria Central*
VS Victoria South Eastern*

*Fringe box, signals not controlled in this simulation.

Non-prefixed signals controlled by London Bridge (L).

Credits and Acknowledgements

My thanks go to a long time signaller at London Bridge who has chosen not to be named; Paul Curran and Noel Young for local expertise from a Control point of view; Alan Gilchrist, Karl Latham, Mark C, and Richard Houghton for testing; “Bob” (another unnamed) for interlocking knowledge; and John Mills for timetabling.

Known Issues

Known Issues and Version History

After 2014

London Bridge started to be resignalled during 2014 with works really ramping up through 2015 to 2018. The highest numbered platforms at London Bridge Low Level station were started first, with work progressing over the next few years, taking out 2-4 platforms at a time until platform 1 was finished. Periods of this work included no trains stopping at London Bridge High Level on some lines.

Meanwhile, additional work took place at New Cross Gate to add extra crossovers around the Up Sussex Loop. In between London Bridge and Spa Road / Bricklayers Arms junctions a huge amount of work took place, reconfiguring the track layout and adding a flyover to eliminate the Thameslink crossing moves at Spa Road and Blue Anchor.

Finally (ignoring a few other changes), a new pair of lines between Metropolitan Junction and London Bridge were added. Trains from/to Charing Cross are still limited to two tracks but Thameslink trains now get their own pair of tracks from Blackfriars.

Once finished, the whole area will be controlled from Three Bridges ROC.


Last edited by Steamer on 04/07/2018 at 23:00