Are 16 Car Trains feasible on Southern?

[21C101]

Various threads discuss the peak congestion on the Southern main lines.

I'm wondering if some limited use of 16 car trains would provide an answer, these could split into two 8 car trains further south.

Brighton Line

Victoria - Eastern - accessed from Brighton Main fast lines via Stewarts lane low level route.

East Croydon - Extend 1&2 northwards, 3&4 southwards.

Gatwick - Extend 1,2,3,4 & 7 northwards.

Haywards Heath- Extend all four platforms Northwards.

16 Car services depart Victoria (E), call at East Croydon, Gatwick airport and Haywards Heath where they divide and go on in appropriate portions (8+8 or 12+4)

South Eastern Main Line

New build 140mph capable 16 car trains depart from Waterloo Eurostar and run to Ashford via Longfield and CTRL or via Tonbridge (fast), divide at Ashford. (as an aside it surprises me that no Javelins go to Victoria via Longfield in the peaks).

 

[Manchester77]

South Eastern Main Line

New build 140mph capable 16 car trains depart from Waterloo Eurostar and run to Ashford via Longfield and CTRL or via Tonbridge (fast), divide at Ashford. (as an aside it surprises me that no Javelins go to Victoria via Longfield in the peaks).

Wasn't the SWML supposed to get a 16 car capable flyover as part of the HLOS or something?

I'll just say that Waterloo International is accounted for for quite some time while platforms 1-4 are rebuilt and points moved to allow 10 car suburban working. This will see all platform allocations move up with the Windsor lines occupying international.

Also, 16 car trains on third rail maybe pushing the system too much. How many substations will have to be built to allow this. Especially on modern trains with all their fancy power consuming features (AC, power doors, TMS, retention tank loos, PIS, etc.)

 

[NotATrainspott]

When you go beyond 12 cars you start to really suffer from the law of diminishing returns. It isn't just the platform lengths that are important, it's the 33% extra time spent in each signal block or the lengths available in the depot. Remember that you need to be able to rescue a 16 car train with another 16 car train, so in exceptional circumstances you could be looking at a 640m long DC-powered train that would need to be able to fit through junctions and into depots.

All of this was looked at in a report by Network Rail (along with double-deck trains). Once the Brighton Main Line or equivalent is totally filled with the maximum number of 240m AC-powered trains as is possible, the only realistic next step is to build another new line for express trains. At the start this can just be a pair of tunnels from the central London terminus to around the M25, allowing all out-of-M25 services to run fast (maybe with a limited number of stations at critical places, OOC-style) into the city centre terminus. The existing track space freed up within the M25 can then be used entirely for within-the-M25 services, which then would run into Crossrail tunnels through London instead of terminating.

 

[Fincra5]

The simple answer is no...

The platforms you say about extending aren't feasible.. so many junction rebuilds required and all sorts. Brighton wouldn't be poss.

 

[edwin_m]

it's the 33% extra time spent in each signal block or the lengths available in the depot.

A longer train does spend a bit longer in a signal block, but the extra is much less than proportional to the train length.

 

[NotATrainspott]

A longer train does spend a bit longer in a signal block, but the extra is much less than proportional to the train length.

Yes, I confused myself when writing. It's true that they'll take longer in a signal block, but the 33% figure will be on things like crossing flat junctions, which are a problem on the Southern network. That extra time could be enough to force reductions in frequency unless very expensive grade-separation jobs were done, which does negate much of the extra capacity you would bring to the network.

 

[306024]

Plus of course it would only work if you put the extra 4 cars on the back, no one is going to walk to the front of a 16 car train.

 

[Manchester77]

16x 20m coaches = 320m which is longer than some intercity sets I'd imagine

 

[VauxhallandI]

Imagine searching for the TM to buy a ticket....

 

[30907]

Various threads discuss the peak congestion on the Southern main lines.

I'm wondering if some limited use of 16 car trains would provide an answer, these could split into two 8 car trains further south.

Brighton Line
Victoria Eastern - accessed from Brighton Main fast lines via Stewarts lane low level route

Platform 2 is (was?) the only platform capable of taking more than 14 cars, and there's no way of extending the others without blocking the throat which is very tight for width.

 

[starrymarkb]

16x 20m coaches = 320m which is longer than some intercity sets I'd imagine

Longer then all UK domestic ones - Eurostar's 373s and 374s would be the only longer trains.

Unlike the continent we don't have 400m platforms at all Intercity stations.

 

[Manchester77]

Longer then all UK domestic ones - Eurostar's 373s and 374s would be the only longer trains.

Unlike the continent we don't have 400m platforms at all Intercity stations.

Oh yeah corse I forgot and got mixed up with HS2 platforms. I think a 16. Car will be longer than an IEP ten car set too.

 

[Skimpot flyer]

(as an aside it surprises me that no Javelins go to Victoria via Longfield in the peaks).

It does not surprise me. Any commuter whose desired end destination is Victoria itself, is better served by the Javelin train whisking him/her to St Pancras, surely? Jump on the Victoria Line, and reach Victoria in a further 15 minutes. The alternative you propose, coming off HS1, and winding slowly through Kent and through South-East London would be of absolutely no benefit, time-wise. The only people to benefit from such a diversion would be commuters at any intermediate stations the train may call at. Adding still further to the longer-distance commuter's journey time!
Isn't using a Javelin on non-High-Speed routes rather a waste, of an excellent resource?

 

[Tomnick]

Yes, I confused myself when writing. It's true that they'll take longer in a signal block, but the 33% figure will be on things like crossing flat junctions, which are a problem on the Southern network. That extra time could be enough to force reductions in frequency unless very expensive grade-separation jobs were done, which does negate much of the extra capacity you would bring to the network.

A 33% longer train might physically occupy a flat crossing for 33% more time, but it won't use 33% more capacity - the time between the route being set over the crossing and the front of the train arriving is far more significant, and wouldn't change.

 

[D1009]

Longer then all UK domestic ones.

Apart from the Scottish sleepers, which may not be "domestic" in the future.

 

[thelem]

Platform 2 is (was?) the only platform capable of taking more than 14 cars, and there's no way of extending the others without blocking the throat which is very tight for width.

Platform 2 where, Victoria? Looking at Google maps there looks to be space between the groups of lines on the west that go undercover first. Or you could use the current retail space in front of the platforms.

If Victoria's practical then you'd only need to extend at Brighton and you could run longer trains on Victoria-Brighton fasts. That should be easy as there are only sidings in the way (and land nearby that the sidings can be moved to), although it would probably mean the loss of the route from Platform 3 to Lewes.

 

[SpacePhoenix]

Also, 16 car trains on third rail maybe pushing the system too much. How many substations will have to be built to allow this. Especially on modern trains with all their fancy power consuming features (AC, power doors, TMS, retention tank loos, PIS, etc.)

I remember reading somewhere that modern 3rd rail trains are locked to a reduced power so presumably 10-12 cars is the absolute limit that 3rd rail can handle so you'd probably be looking at a complete conversion of 3rd rail routes to overhead AC to be able to have 16 coach trains.

After that as already mentioned there's the length of block sections, lengths of platforms etc to consider

 

[Kentish Paul]

Platform 2 where, Victoria? Looking at Google maps there looks to be space between the groups of lines on the west that go undercover first. Or you could use the current retail space in front of the platforms.

If Victoria's practical then you'd only need to extend at Brighton and you could run longer trains on Victoria-Brighton fasts. That should be easy as there are only sidings in the way (and land nearby that the sidings can be moved to), although it would probably mean the loss of the route from Platform 3 to Lewes.

According to Quail, Platform 2 at London Victoria can take "14/17" coaches.

I think the difference is due to the crossover from platforms 3-5 that joins at the end of platform 2 and whether you foul it or not.

 

[physics34]

the answer is resignalling, rengineering the selhurst triangle, East Croydon avoiding lines and a better timetable not longer trains.

 

[Class377/5]

I remember reading somewhere that modern 3rd rail trains are locked to a reduced power so presumably 10-12 cars is the absolute limit that 3rd rail can handle so you'd probably be looking at a complete conversion of 3rd rail routes to overhead AC to be able to have 16 coach trains.

After that as already mentioned there's the length of block sections, lengths of platforms etc to consider

Not really. Southern have run 16 car ECS on the BML. It does require a fudge on the MITRAC but can be done. There a video on YouTube of a 23 car Electrostar with an 11 car pulling a failed 12 car at 5mph.

There's no need to go 16 cars as NR has an solution to increases the paths on the BML post KO2. Can't say more.

And for the record, an 8 car will be able to rescue a failed 16 car. Won't be the quickest thing, especially of all 16 coaches are dead (unlikely).

 

[swt_passenger]

Wasn't the SWML supposed to get a 16 car capable flyover as part of the HLOS or something?

Not in any HLOS so far. 16 car on SWML has appeared as an option in certain relevant RUSs, but really only so that it can be shown why it hasn't been recommended.

 

[Busaholic]

Platform 2 where, Victoria? Looking at Google maps there looks to be space between the groups of lines on the west that go undercover first. Or you could use the current retail space in front of the platforms.

If Victoria's practical then you'd only need to extend at Brighton and you could run longer trains on Victoria-Brighton fasts. That should be easy as there are only sidings in the way (and land nearby that the sidings can be moved to), although it would probably mean the loss of the route from Platform 3 to Lewes.

Assuming there hasn't been a renumbering of platforms at Victoria in the twelve months since I was last there, Platform 2 is on the SouthEastern side, where the Golden Arrow and all the boat trains departed from in days of yore. Even if physically possible you think it would be a good idea to swing a 16-coach train across all the other tracks in order to access Platform 2? I've known Victoria Station since the mid 1950s and I've never known the easternmost platforms (certainly 1-4) be used for anything other than the lines out to Brixton.

 

[MCR247]

You can get from the SE side to CLJ via Stewarts Lane

 

[Busaholic]

You can get from the SE side to CLJ via Stewarts Lane

I still ask why you would run one Brighton line service from Platform 2 when all the others are being run from high-numbered platforms, like 15-19? Victoria is actually two originally unconnected stations and, even today, while 'knocked through' this is immediately apparent to anyone with an eye for detail. Lots of regular travellers on one side or the other will rarely venture to the other side as their train never goes from it.

 

[21C101]

You can get from the SE side to CLJ via Stewarts Lane

indeed, directly onto the fast lines too
--- old post above --- --- new post below ---

I still ask why you would run one Brighton line service from Platform 2 when all the others are being run from high-numbered platforms, like 15-19? Victoria is actually two originally unconnected stations and, even today, while 'knocked through' this is immediately apparent to anyone with an eye for detail. Lots of regular travellers on one side or the other will rarely venture to the other side as their train never goes from it.

My idea was that they would split at HH so all the littlehampton/eastbourne services would go on that side.

 

[SpacePhoenix]

Not really. Southern have run 16 car ECS on the BML. It does require a fudge on the MITRAC but can be done. There a video on YouTube of a 23 car Electrostar with an 11 car pulling a failed 12 car at 5mph.

There's no need to go 16 cars as NR has an solution to increases the paths on the BML post KO2. Can't say more.

And for the record, an 8 car will be able to rescue a failed 16 car. Won't be the quickest thing, especially of all 16 coaches are dead (unlikely).

Would the power supply cope with the load with all systems running normally and each unit drawing normal loads from the juice rail?

 

[Class377/5]

Would the power supply cope with the load with all systems running normally and each unit drawing normal loads from the juice rail?

16 car ECS ran at line speed as far as I know.

The problem is lots of them around at the same time. What's not widely known is the introduction of the 377/5 required power upgrades as does the Class 700s.

 

[AM9]

16 car ECS ran at line speed as far as I know.

The problem is lots of them around at the same time. What's not widely known is the introduction of the 377/5 required power upgrades as does the Class 700s.

4x4-car modern EMUs would draw a peak current over 4000A. The 12-car 700s are reported to be 5000A. The system can only support about 8000A per section so if there were more than one long train on the same section, - or even one long and a 12-car set, the power supply may fail. As I've said before, 750VDC is not very clever when the power demands rise. That's what the Basingstoke to Southampton conversion is all about.

 

[Class377/5]

4x4-car modern EMUs would draw a peak current over 4000A. The system can only support about 8000A per section so if there were more than one long train on the same section, the power supply may fail. As I've said before, 750VDC is not very clever when the power demands rise. That's what the Basingstoke to Southampton conversion is all about.

The BML is being beefed up to cope but as you rightly state, it can only go so far. Longer term AC makes more sense.

 

[30907]

Platform 2 where, Victoria? Looking at Google maps there looks to be space between the groups of lines on the west that go undercover first. Or you could use the current retail space in front of the platforms.

Yes, Victoria. You could extend 7 and 8, the old Boat train platforms, but that leaves space for only one track to access 3-6. There's not much concourse space on the Chatham side to extend north. There would be room on the Brighton side though as 10-15 used to hold 2x8 cars.