norbitonflyer
Established Member
768s were converted from 319s, so refitting the shoes would seem a simpler option if you want a 3rd-rail capable parcels unit..Perhaps they've been deemed as more flexible as they can use 3rd rail?
768s were converted from 319s, so refitting the shoes would seem a simpler option if you want a 3rd-rail capable parcels unit..Perhaps they've been deemed as more flexible as they can use 3rd rail?
That's true, unless another operator want them?768s were converted from 319s, so refitting the shoes would seem a simpler option if you want a 3rd-rail capable parcels unit..
3) No plans to put battery packs on GWR's 387's and 800's. So I would assume new trains with third-rail, battery and/or diesel. However battery EMU's would affect performance, reliability and speed issues because of the additional weight on the train.You could but there’s a couple of very big hoops to jump through:
1) convince ORR of the safety aspects as they have concerns about new third rail. They haven’t said totally no but need a lot to convince them.
2) funding, this will be an even bigger hurdle. Third Rail needs substations to power it, neither of these grow on trees. The Railway isn’t exactly flush at the moment.
768s were converted from 319s, so refitting the shoes would seem a simpler option if you want a 3rd-rail capable parcels unit..
It's not that simple. Any requirement to use a 3rd rail supply would require additional switchgear to prevent the shoes being live when the gensets are running, plus, the ground return cabling between the gensets and the motor car might need modifiying. All this was completed with the 769/9s that GWR was intending to deploy..3) No plans to put battery packs on GWR's 387's and 800's. So I would assume new trains with third-rail, battery and/or diesel. However battery EMU's would affect performance, reliability and speed issues because of the additional weight on the train.
You could but there’s a couple of very big hoops to jump through:
1) convince ORR of the safety aspects as they have concerns about new third rail. They haven’t said totally no but need a lot to convince them.
2) funding, this will be an even bigger hurdle. Third Rail needs substations to power it, neither of these grow on trees. The Railway isn’t exactly flush at the moment.
3) No plans to put battery packs on GWR's 387's and 800's. So I would assume new trains with third-rail, battery and/or diesel. However battery EMU's would affect performance, reliability and speed issues because of the additional weight on the train.
Would that be steel sleepers?4) Some of the track (definitely) and signallign (probably) isn‘t compatible with third rail.
Yes, as 'Bald Rick' posted nearly ten years ago in a post which suggested the line would never be electrified - https://www.railforums.co.uk/threads/redhill-reading.103510/#post-1858025Would that be steel sleepers?
What is the typical life of a steel sleeper? They are presumably much cheaper than concrete sleepers.Yes, as 'Bald Rick' posted nearly ten years ago in a post which suggested the line would never be electrified - https://www.railforums.co.uk/threads/redhill-reading.103510/#post-1858025
Also, https://www.railforums.co.uk/threads/steel-sleepers.95790/page-2#post-1694669
If you look back in the threads, a steel sleepers was more expensive than a concrete sleeper, but could be placed on less ballast so overall worked out cheaper.What is the typical life of a steel sleeper? They are presumably much cheaper than concrete sleepers.
Has it ever been suggested that OHLE is impossible?Yes, as 'Bald Rick' posted nearly ten years ago in a post which suggested the line would never be electrified - https://www.railforums.co.uk/threads/redhill-reading.103510/#post-1858025
Also, https://www.railforums.co.uk/threads/steel-sleepers.95790/page-2#post-1694669
Pretty sure they haven't relaid in steels on any of the non electrified sections as policy on Southern area was always to use concretes so no issues with future electrification however fanciful that might be.Would that be steel sleepers?
Not impossible, but expensive to install two isolated sections of 25kV and the potential for problems at each of the four changeover points. (Look at gtthe numbver of time pantographs get entangled in the roof of Blackfriars station, and I think tyhe tiunnel mouth at Drayton Park has collected a few as well)Has it ever been suggested that OHLE is impossible?
There are substations at Dorking (North) and (I recall) somewhere near Farnborough already which are a good start.You could but there’s a couple of very big hoops to jump through:
1) convince ORR of the safety aspects as they have concerns about new third rail. They haven’t said totally no but need a lot to convince them.
2) funding, this will be an even bigger hurdle. Third Rail needs substations to power it, neither of these grow on trees. The Railway isn’t exactly flush at the moment.
A short run off extension at Wokingham would probably be acceptable, and perhaps Shalford too.Not impossible, but expensive to install two isolated sections of 25kV and the potential for problems at each of the four changeover points. (Look at gtthe numbver of time pantographs get entangled in the roof of Blackfriars station, and I think tyhe tiunnel mouth at Drayton Park has collected a few as well)
It could be limited to two changeovers if the wires are carried through Guildford (although that would get expensive because of the tunnel south of Guildford station), or just one if you extend them beyond Wokingham to link up with the existing wires at Reading, but signal immunisation is difficult if you have both ac and dc traction current present (track circuits generally use dc in ac territory and vice versa, to avoid interference from the return current in the running rails).
A short run off extension at Wokingham would probably be acceptable, and perhaps Shalford too.Not impossible, but expensive to install two isolated sections of 25kV and the potential for problems at each of the four changeover points. (Look at gtthe numbver of time pantographs get entangled in the roof of Blackfriars station, and I think tyhe tiunnel mouth at Drayton Park has collected a few as well)
It could be limited to two changeovers if the wires are carried through Guildford (although that would get expensive because of the tunnel south of Guildford station), or just one if you extend them beyond Wokingham to link up with the existing wires at Reading, but signal immunisation is difficult if you have both ac and dc traction current present (track circuits generally use dc in ac territory and vice versa, to avoid interference from the return current in the running rails).
Still no acknowledging the safety case here then?There are substations at Dorking (North) and (I recall) somewhere near Farnborough already which are a good start.
In any event the GWR Churchward stock project would I suspect have a batch for dc and diesel (or battery) and perhaos ac too for Gatwick and Portsmouth to Bristol trains.
A short run off extension at Wokingham would probably be acceptable, and perhaps Shalford too.
A short run off extension at Wokingham would probably be acceptable, and perhaps Shalford too.
Whilst there is one, same as there would be for AC, doesn't mean it can't be done.Still no acknowledging the safety case here then?
You can step on a third rail. To get close enough to OHLE to be killed you have to try pretty hard. For that reason new third rail is very unlikely (never) going to be installed. Sticking batteries under trains is far cheaper anyway.Whilst there is one, same as there would be for AC, doesn't mean it can't be done.
There's little to no point not infilling 3rd Rail Islands due to the slim chance of an incident involving the CRE.
There were going to be nineteen of them, so presumably at least nineteen 16xs would have been released - probably more, as a single 4-car 769 could replace 2x2car 165s (or, at a pinch, a 2+3 pairing).If GWR's 769s had been introduced, how many 16xs would that have released?
There were going to be nineteen of them, so presumably at least nineteen 16xs would have been released - probably more, as a single 4-car 769 could replace 2x2car 165s (or, at a pinch, a 2+3 pairing).
Haven't London Transport recently (or about to) laid some brand new third rail to Battersea ?You can step on a third rail. To get close enough to OHLE to be killed you have to try pretty hard. For that reason new third rail is very unlikely (never) going to be installed. Sticking batteries under trains is far cheaper anyway.
From memory there is also something in Frimley area, might even be disconnected switchgear from days when Sturt Lane spur existedThere are substations at Dorking (North) and (I recall) somewhere near Farnborough already which are a good start.
You would probably also need to also need the short section from Dorchester junction to station too, to allow same stock on Bristol-Weymouth trains. Without it, going to have to take the 25kv further towards Frome to avoid problems with battery range.In any event the GWR Churchward stock project would I suspect have a batch for dc and diesel (or battery) and perhaos ac too for Gatwick and Portsmouth to Bristol trains.
There is strong case for short third rail extensions on approach tracks, rather than run off. The basis being that battery trains might be stopped at junction approach signal, and if stopped, better to change system there, especially if can accelerate faster on line power than batteries. Only needs to be about 150m before junction signal, even the back set of a double unit would have a shoe on third rail.A short run off extension at Wokingham would probably be acceptable, and perhaps Shalford too.
I think laying third rail in a tunnel is rather different!Haven't London Transport recently (or about to) laid some brand new third rail to Battersea ?
I think the runoff extensions suggested were for extending the knitting to a point where the overheight detection system has time to operate and drop the pantograph before it hits an overhead structure (as does not happen at Blackfriars!). The problem at Shalford would be that it would require extending the wires through the tunnel immediately south of Guildford station, which would mean lowering the track (which may be aflood risk, as the River Wey is nearby) or raising the roof.There is strong case for short third rail extensions on approach tracks, rather than run off.
1. London Transport (as London Regional Transport, LRT) was abolished in 2000.Haven't London Transport recently (or about to) laid some brand new third rail to Battersea ?
Would have made such a big, positive, improvement to Devon metro and Cardiff-PortsmouthThe original plan for the 759 units was that they would release all 16 of the 165/1 3 cars to the west. Post Crossrail, all London area Turbos operated single diagrams, so no 1 x 769 for 2 x Turbo release opportunities existed.
Yes, not for the North Downs though. No line deserves any form of 319, especially not one serving SurreyWould have made such a big, positive, improvement to Devon metro and Cardiff-Portsmouth
C'est la vie
But the 769s were going to be longer than the Turbos…Yes, not for the North Downs though. No line deserves any form of 319, especially not one serving Surrey![]()
Why not? It would give the entitled, self-assured residents of Surrey a taste of what we have to put up with 'oop North'! (Wink!). And don't forget....the 319s served Surrey - and Sussex - well for many years on Thameslink routes.Yes, not for the North Downs though. No line deserves any form of 319, especially not one serving Surrey![]()
Obviously I was only saying it tongue in cheek, as a way of saying keep them well away from me (loathsome trains)Why not? It would give the entitled, self-assured residents of Surrey a taste of what we have to put up with 'oop North'! (Wink!). And don't forget....the 319s served Surrey - and Sussex - well for many years on Thameslink routes.
It certainly would, though I seem to recall that it would have sent some or all of the 150's off lease?Would have made such a big, positive, improvement to Devon metro and Cardiff-Portsmouth
C'est la vie
Wouldn't be all because of the Cornish Branches particually Gunnislake,Looe,NewquayIt certainly would, though I seem to recall that it would have sent some or all of the 150's off lease?