3tph on North Downs Line

[FenMan]

How does a 2 tph Sunday timetable example help when considering a weekday 3tph timetable (with a much busier railway, with different timings anyway)?

Because the much revised timetable that appeared on Realtime Trains last spring had departures from Reading and Gatwick at these times (the timings were canned soon after - I should have taken a screenshot). I didn't need to be an expert to spot the timings of a stopper that could be overtaken at Guildford. Indeed there's one example in the current weekday timetable - look at the 0903 ex-Gatwick and the 0851 ex-Redhill.

The missing other Gatwick - Reading, with the current scheduled stopping pattern, would be on the other half hour.

 

[JonathanH]

No, you are misremembering what was on the open data feed - off peak what appeared were fast services from Reading at xx04 and stoppers at xx20 with a long layover at Guildford for a xx34 to be allowed to pass (The xx34 never appeared but it was apparent that it is what was intended). That is not the Sunday timetable. There was a bit of a mix in the peaks. Towards Reading, the trains were shown leaving Redhill at xx00 for slows and xx30 from Gatwick with the missing xx00 from Gatwick overtaking at Guildford during the long layover of the xx00 from Redhill.

xx18 / xx48 departures from Reading for the fast might be desirable for Reigate to London Bridge connections at Redhill but it doesn't fit in the available paths at Redhill for Gatwick.

The timing of the 0851 from Redhill / 0903 from Gatwick is a fix resulting from the impossibility of getting the 0734 train from Reading to run to Gatwick in the standard path from Redhill because it needs to run as a stopper into Guildford. Instead the 0704 from Reading runs through to Gatwick with five minutes at Guildford and five minutes at Reigate to make it fit.

 

[FenMan]

How does a 2 tph Sunday timetable example help when considering a weekday 3tph timetable (with a much busier railway, with different timings anyway)?

You're absolutely correct. Thank you.

 

[Deepgreen]

Back on the NDL today, and the slightly late 1718 from Reigate (ex-Gatwick) to Reading arrived at Dorking Deepdene with the platform DMI showing it, but, immediately after, as people were still boarding (and running up the stairs to catch it), the screen changed to show the following train! Farcical.

 

[big all]

Back on the NDL today, and the slightly late 1718 from Reigate (ex-Gatwick) to Reading arrived at Dorking Deepdene with the platform DMI showing it, but, immediately after, as people were still boarding (and running up the stairs to catch it), the screen changed to show the following train! Farcical.

assuming its still the same [many years retired]the track circuit for deepdene is back clear off brockham so assume the screen will update shortly crossing brockam barriers ??

 

[JN114]

Back on the NDL today, and the slightly late 1718 from Reigate (ex-Gatwick) to Reading arrived at Dorking Deepdene with the platform DMI showing it, but, immediately after, as people were still boarding (and running up the stairs to catch it), the screen changed to show the following train! Farcical.

The system can only go off the information it knows. The last time the position of the train is known by the signalling system - and thus the industry as a whole - is once it passes over Brockham LC. The next point it knows about is passing RG91 signal about a mile east of Dorking Town. What you witness is the lesser of two evils.

Either it can clear off, as it does now, a certain time offset after the train passes Brockham LC, or it can remain on the screen until the train has passed/departed Dorking Town and run for a mile. I'm sure you'd describe it as even more "farcical" if trains were lingering on the screens minutes after they'd departed, luring latecomers into thinking the train was late and they hadn't missed it.

Until the Guildford - Reigate section of the NDL is resignalled, it will stay that way.

 

[JN114]

assuming its still the same [many years retired]the track circuit for deepdene is back clear off brockham so assume the screen will update shortly crossing brockam barriers ??

Correct - I can't recall the offset off hand but it's (essentially) one long TC from clear of Brockham AHB up to/including the overlap of RG91, so both Deepdene and Town on the Down are time @ Brockham + offset

 

[JonathanH]

Until the Guildford - Reigate section of the NDL is resignalled, it will stay that way.

Presumably there is a very good chance that the line will never be resignalled. It must be some way down the list (despite the fact that the current signalling is very basic and results in long headways).

 

[big all]

Correct - I can't recall the offset off hand but it's (essentially) one long TC from clear of Brockham AHB up to/including the overlap of RG91, so both Deepdene and Town on the Down are time @ Brockham + offset

if you had a heavy freight following a slow i would ask the signalman at betchworth to to pull off the signal as the stopper was arriving at gomshall and hope i had judge it right as you come round the corner at dorking town

 

[A Challenge]

Is the signal spacing the other side of Guildford (through Blackwater) any better?

 

[JN114]

Is the signal spacing the other side of Guildford (through Blackwater) any better?

No, not really.

 

[big all]

used to be northcamp just passed blackwater about 12 coach lengths then 1 mile short off wokingham

 

[DelW]

The infamous Wokingham junction points seem to have been misbehaving again this morning, with NDL trains either cancelled or running up to an hour late. For a while, from about 8am, GWR appeared to be running a Guildford - Redhill shuttle service using units trapped east of the problem. At least one Reading-bound train was terminated at Guildford and sent back to Redhill, and another seems to have been turned back at Ash.

 

[Dren Ahmeti]

The infamous Wokingham junction points seem to have been misbehaving again this morning.

At least Wokingham SB didn’t give the SW a Blackwater routing or the GW a Southern routing at the junction again!

 

[Aictos]

I have a question about the signalling headways on the line in question now according to Wikipedia as I'm not too familiar with the signalling headways it states:

That Wokingham to North Camp has headways of 6 minutes for fast services and 11 minutes for stopping services due to the longest headways on the line now is it possible to resignal this section to reduce the headways?

I am aware that it is planned to transfer control of Wokingham Signal Box to the new Rail Operating Centre in Basingstoke in 2017/18 if not already happened?

I ask because does the proposed 3tph require the work to be done?

 

[JonathanH]

If the fast leaves Reading at xx04/xx34 and the slow at xx20 there should be no problem with the headways for 3tph when everything is running smoothly. You can see this is the current timetable when the extra train runs to Guildford - e.g. 0820 between an 0804 and 0838, 1651 between a 1632 and 1704.

The idea was that the stopper is overtaken at Guildford.

 

[acs3141]

The infamous Wokingham junction points seem to have been misbehaving again this morning, with NDL trains either cancelled or running up to an hour late. For a while, from about 8am, GWR appeared to be running a Guildford - Redhill shuttle service using units trapped east of the problem. At least one Reading-bound train was terminated at Guildford and sent back to Redhill, and another seems to have been turned back at Ash.

I was stuck on a gwr reading bound train at the signal just before the points. guard was having to walk up and down the train to make announcements as the intercom was not working well. not sure what actually happened, open train times indicated that there was a block on all lines. the train then pulled away. the guard was very surprised as he walked through the carriage. from the announcements I think we all thought we were in for a long wait.

 

[Wilts Wanderer]

I have a question about the signalling headways on the line in question now according to Wikipedia as I'm not too familiar with the signalling headways it states:

That Wokingham to North Camp has headways of 6 minutes for fast services and 11 minutes for stopping services due to the longest headways on the line now is it possible to resignal this section to reduce the headways?

I am aware that it is planned to transfer control of Wokingham Signal Box to the new Rail Operating Centre in Basingstoke in 2017/18 if not already happened?

I ask because does the proposed 3tph require the work to be done?

The proposed 3tph fits through the existing infrastructure. Indeed the detailed timetable work was all completed, only to be scuppered at the last moment by the level crossing safety assessments.

 

[big all]

4 trains per hour is no more difficult than 3 trains per hour assuming the 2 fasts are at 30 min clock face spacings as are the stoppers
the problems only come when you have all three say within 25 mins so when the stopper follows the fast from guildford it will leave say 4 mins behind
this will place it perhaps 9 or 10 by sandhurst clearing wokingham home signal say 7 or 8 mins later placing the fast at blackwater getting the clear signal 18- 20 mins behind

 

[Dren Ahmeti]

4 trains per hour is no more difficult than 3 trains per hour assuming the 2 fasts are at 30 min clock face spacings as are the stoppers
the problems only come when you have all three say within 25 mins so when the stopper follows the fast from guildford it will leave say 4 mins behind
this will place it perhaps 9 or 10 by sandhurst clearing wokingham home signal say 7 or 8 mins later placing the fast at blackwater getting the clear signal 18- 20 mins behind

The NDL signal spacing isn’t the issue, it’s the paths available at Reading, Guildford through to Shalford Jct and especially the Brighton Main Line at Redhill through to Gatwick.
As you know, Sussex refuses the GTW train if they’re more than a couple of minutes late; losing your path down there equates to a painful cancellation at Redhill.

 

[Deepgreen]

The system can only go off the information it knows. The last time the position of the train is known by the signalling system - and thus the industry as a whole - is once it passes over Brockham LC. The next point it knows about is passing RG91 signal about a mile east of Dorking Town. What you witness is the lesser of two evils.

Either it can clear off, as it does now, a certain time offset after the train passes Brockham LC, or it can remain on the screen until the train has passed/departed Dorking Town and run for a mile. I'm sure you'd describe it as even more "farcical" if trains were lingering on the screens minutes after they'd departed, luring latecomers into thinking the train was late and they hadn't missed it.

Until the Guildford - Reigate section of the NDL is resignalled, it will stay that way.

No, I wouldn't, because this happens at many places and the impact is far less on people arriving after the train has gone - i.e. they may wait a few minutes before the right train is displayed. I would far rather an-already departed train was still showing for a short time, than an arrived train NOT showing, and another one, with a different stopping pattern, in its place! From the passengers' (rather than operators') perspective, the TOCs' bleatings over decades that they take accurate information so seriously consistently fail to deliver improvements.

By "Dorking Town" do you mean Dorking West? I am confused by your mention of signal RG91 being east of "Dorking Town" (Dorking West?) and then mention of a location a mile after the station (i.e. west) being the next updating point.

 

[Deepgreen]

The proposed 3tph fits through the existing infrastructure. Indeed the detailed timetable work was all completed, only to be scuppered at the last moment by the level crossing safety assessments.

The level crossing assessments which are presumably insoluble, as Betchworth and Reigate alone are regarded as at capacity now regarding traffic build-up. I'm still amazed (or perhaps not!) that this issue was seemingly ignored by timetable planners, NR, TOCs, et al.

 

[JonathanH]

The level crossing assessments which are presumably insoluble, as Betchworth and Reigate alone are regarded as at capacity now regarding traffic build-up. I'm still amazed (or perhaps not!) that this issue was seemingly ignored by timetable planners, NR, TOCs, et al.

It has been suggested that it was the other, less significant crossings, rather than those at Reigate and Betchworth, that were the main problem with the 3tph plan - and it was a safety rather than closure time issue.

Dorking West was known as Dorking Town until 1987 which is why its three letter code is DKT (and not presumably DKW). At the same time Deepdene became Dorking Deepdene.

 

[Wilts Wanderer]

4tph would probably be very difficult at Guildford with the overtaking of stoppers in potentially both directions simultaneously requiring more platforms than currently exist.

 

[Bikeman78]

The level crossing assessments which are presumably insoluble, as Betchworth and Reigate alone are regarded as at capacity now regarding traffic build-up. I'm still amazed (or perhaps not!) that this issue was seemingly ignored by timetable planners, NR, TOCs, et al.

What is the problem with Reigate level crossing? There are numerous level crossings between Brighton and Littlehampton, that line has six trains per hour in each direction.

 

[Dren Ahmeti]

What is the problem with Reigate level crossing?

With all respect, have you seen the location of it, in respect to the town itself? It’s practically in the town centre, with shops in a line on either side of the road.
The amount of traffic that goes over the LC 24/7 is insane; it’s very similar to Sunningdale on the A30 that will back traffic up for miles if it’s left down too long.

 

[big all]

4tph would probably be very difficult at Guildford with the overtaking of stoppers in potentially both directions simultaneously requiring more platforms than currently exist.

if they leave reading and redhill clock face because guildford is not exactly in the middle the departing fast to reading would clear say number 5 leaving it for the reading to gatwick fast with only the stoppers needing there own platform

 

[JonathanH]

With all respect, have you seen the location of it, in respect to the town itself? It’s practically in the town centre, with shops in a line on either side of the road.
The amount of traffic that goes over the LC 24/7 is insane; it’s very similar to Sunningdale on the A30 that will back traffic up for miles if it’s left down too long.

Er, no shops on London Road, Reigate other than a Co-op and a bridal shop. There are plenty of offices however.

It is fair to say that the A217 is the only practical route from Reigate to the M25 and a relief road to the M23 for some traffic towards Gatwick.

Having said that, there has been 3tph over this route at various times in the past and some of it will be timed to meet there reducing the time the crossing barriers are down.

 

[JonathanH]

if they leave reading and redhill clock face because guildford is not exactly in the middle the departing fast to reading would clear say number 5 leaving it for the reading to gatwick fast with only the stoppers needing there own platform

The problem is that the slow trains need to be in the platform at Guildford for nigh-on 10 minutes because of the headways for the faster trains.

 

[big all]

The problem is that the slow trains need to be in the platform at Guildford for nigh-on 10 minutes because of the headways for the faster trains.

yes i understand that thats why i said they need there own platform
perhaps i should have said a platform each to make it clearer??
as the fast will only dwell for say 2 mins they can pass between the cathedral and old dennis factory and share the same platform