I seem to recall that running the slows to Letchworth was purely for operational simplicity to avoid the former cumbersome reversal north of Stevenage station, which blocked the fast lines as trains moved from the west to east side of the station. If there was any consideration on bringing them back then they wouldn't be spending big money on the current project.Having a through line might be useful for freight, pathing, disruption, whatever.... but agreed that this works for its core purpose. And slows to Letchworth aren't returning, correct?
Two new signals on the down slow and down fast will be erected and brought into use. All the old lineside cabinets in the worksite will go and the new ones next to the new line brought into use.
Bringing the thread back on track (punn intended) I received the following information from one of the chaps working on site over Christmas
The gentleman in question specialises in the track signalling testing, so only has the above info and can't advise what (if any) other works are involved.
I've also been informed by Spencer's that there will be some minor OLE, power and s small amount of telecoms work planned. My guess is that now all the masts are up, the insulators etc might get fitted, we'll just have to wait and see.
Spencer's also informed me that in early 2020 they hope to hold a "meet the team" event where questions on the project can be asked. I hope to cover this in a future update, and possibly will ask some of the points raised here (to do with construction not if TfL will be taking over the operation etc)
There appears to be a new signal for Down moves on the new track alongside the other Down signals in the photo in #473. I think it has an X on it, which would confirm it is for Down moves. This may be because there are signals on the other two Down lines and normal practice is to have parallel signals to minimize risk of driver confusion between them. It may also be to allow a second train into the new platform, possibly only for coupling, although I can't tell if there is a subsidiary aspect. If there was no signal in between then the second train move would require a subsidiary on the previous signal (the one that gets the junction indicator) and the second train would have to run slowly all the way from that signal to the platform. I don't recall if there is some standard that limits the length of such a permissive move.I was thinking that the only signal that would need modification / changing would have been the one just south of the A602 bridge before the back to back points, so that a route indicator is fitted to indicate if the approaching train is to go into platform 5 or join the down slow. But then there are two existing signals (down slow and down fast) a few hundred metres north of the junction so maybe the new signal is to go on the new track next to them, but facing south so a train can be held prior to the points in the event a train is in the section between Bragbury end and Langley junction and is routed to the down slow.
Because it is driven from all new equipment
There appears to be a new signal for Down moves on the new track alongside the other Down signals in the photo in #473. I think it has an X on it, which would confirm it is for Down moves. This may be because there are signals on the other two Down lines and normal practice is to have parallel signals to minimize risk of driver confusion between them. It may also be to allow a second train into the new platform, possibly only for coupling, although I can't tell if there is a subsidiary aspect. If there was no signal in between then the second train move would require a subsidiary on the previous signal (the one that gets the junction indicator) and the second train would have to run slowly all the way from that signal to the platform. I don't recall if there is some standard that limits the length of such a permissive move.
As to the Up direction signals on the new track, there will have to be one controlling departure from the platform which presumably is parallel with the other platform starter signals. I'm not sure the operational benefit of having another one between the platform and the junction is enough to justify it. It would allow a train to leave the platform on a yellow when another train was approaching on the Down Hertford heading for the Down Slow, thus saving it a few seconds as it would get closer to the junction.
I'm also at a loss regarding any new signal on the Down Slow or Down Fast.
However that defective train would either need to be approaching from Hertford or to do a complicated shunt at the junction to get into platform 5. If it was ever made into a complete loop, wouldn't the platform also be extended?In a perfect world the new platform would be 12 cars in order to give somewhere to recess a defective train - as well as a bit of future proofing should the new line ever become a loop - but that’s extra £££. This does seem to be a real “do minimum” project just to allow the Stevenage to Hertford train service to run at all.
I wonder if for those of us that are not so familiar with the details at this point of the track, could someone add some graphical references please.As of now the signal post on the new section doesn’t have a position light on it. Although the existing move into platform 4 does have one, its use has been almost zero over the years - so with the added change of fixed 6-car trains it’s hard to envisage a need for one.
In a perfect world the new platform would be 12 cars in order to give somewhere to recess a defective train - as well as a bit of future proofing should the new line ever become a loop - but that’s extra £££. This does seem to be a real “do minimum” project just to allow the Stevenage to Hertford train service to run at all.
Signal 939 looks to be the one that gets a junction indicator. The new line goes straight on where the line beyond 939 turns right, and continues to a dead end in platform 5 alongside the other platforms. The signal I mentioned a few posts back is alongside 659 and 661.I wonder if for those of us that are not so familiar with the details at this point of the track, could someone add some graphical references please.
Attached is OTT's map of the current Stevenage area, could someone either describe, or annotate the attached, detailing between which of the current signal numbers, the new turnout and new signals look like being (and pointing)?
I'm playing a game of battleships here and seem to be on the loosing side!
Merry Xmas to all.
View attachment 71929
Many thanks - presumably 1978 stays between the new turnout and the existing DS turnout?Signal 939 looks to be the one that gets a junction indicator. The new line goes straight on where the line beyond 939 turns right, and continues to a dead end in platform 5 alongside the other platforms. The signal I mentioned a few posts back is alongside 659 and 661.
I use the Hertford Loop as a passenger from time to time. Signal 939 is definitely where trains wait if the main line is occupied. So that would be a reasonable place to put a junction indicator.Signal 939 looks to be the one that gets a junction indicator.
Yes watching OTT that's where all the Watton terminators go, before returning to Watton on the up line via 1970 and 1964 - you can see the route is set (green) on my attachment above.I use the Hertford Loop as a passenger from time to time. Signal 939 is definitely where trains wait if the main line is occupied. So that would be a reasonable place to put a junction indicator.
View attachment 72286 Works from platform 4 today. Track is not continuous from the junction yet. Foundations for the footbridge in.
The existing OLE support looks to be too close to the new track, so I'm guessing this (and probably at least one more visible in #511) will have to be replaced.View attachment 72287 Shows how the wires will pass under the existing footbridge to the end post. I could also see bagged signals. No wires up yet.
Looks like they have put it in at the same angle as the existing support. This may mean it only gets a cantilever on the Platform 4 side - the end support may be close enough that P5 doesn't need one here.Thanks for the images. It would seem from the first that the pile being driven into the ground in my video was for another OHL mast... which to me doesn't seem to be all that vertical !
Indeed - like the one in post #512, it looks like it'll be a Simply Supported Anchor (or SSA), replacing the Mid Point Anchor (MPA) termination on the existing mast nearest the camera in post #511. The benefit of these is that they don't need a back-tie arrangement - at the cost of a considerably longer-than-average pile.The existing OLE support looks to be too close to the new track, so I'm guessing this (and probably at least one more visible in #511) will have to be replaced.
Looks like they have put it in at the same angle as the existing support. This may mean it only gets a cantilever on the Platform 4 side - the end support may be close enough that P5 doesn't need one here.
How tall is the lift shaft now? Any sign of the legs for the bridge?
Lift shaft is being fitted, and alterations to the bridge.
OHLE connected during February blockade.