Are some trains too long?

[Sorcerer]

Considering that overcrowding and lack of capacity is a huge problem across much of the railway network, I think the question of a train being too long with many free seats is actually a good reflection of the new rolling stock. Of course being articulated Stadler stock in this instance I am lead to wonder whether or not these twelve coaches would still be that length on non-articulated stock such as the 387 or if it would be shorter such as eight or ten coaches.

 

[Railcar]

Southern's popular Epsom to London Bridge semi-fast service is ten coaches for the peaks and splits to five during the day.
There are warnings ahead of Norwood Junction that "the platform is too short" to alight from the tenth coach. No, the train is too long.

 

[swt_passenger]

It’s been explained in the past that when trains such as 8 car SWT 455s were routinely split between the peaks to run as 4 car for a few hours until mid afternoon, the overheads in terms of additional drivers, shunters for the electrical coupling, and the timetabling difficulties of all the extra ECS moves to and from depots on already busy routes, meant that leaving the trains as 8 cars all day on Mon-Sat quickly became the preferred method of operating.

 

[Magdalia]

Southern's popular Epsom to London Bridge semi-fast service is ten coaches for the peaks and splits to five during the day.
There are warnings ahead of Norwood Junction that "the platform is too short" to alight from the tenth coach. No, the train is too long.

I use the Epsom-London Bridge service, and I'm familiar with these splits.

No the 10 car trains are not too long, some of them a very busy around Sutton with school traffic.

There is a thing called selective door opening for stations with short platforms. Selective door opening works particularly well on the Victoria-Horsham trains.

 

[WAB]

I am always tickled by suggestions of splitting XC trains at the extremes of routes to save a couple of units. The delay and cost involved with the shunting as well as the difficulties in keeping sets in the right place in disruption makes it seem not worthwhile.

 

[cambsy]

I dont think trains are too long per se, but they do carry fresh air around at times off peak, but this preferable to short formed etc during the peak, then being too crush loaded, leave passengers behind. i dont think there easy solution to this, to keep units long enough in peaks but not too long off peak.

 

[AF91]

Also loads are not totally predictable, flight delays, passport queues mean that the load is not as predictable as your average train.

It's also a service that you wouldn't want people left behind for lack of capacity. Better to be safe than sorry.

 

[AM9]

Much of the energy consumed in moving a train is aerodynamic drag, which depends primarily on the frontal area - which is the same whether the train has two coaches or twelve.

Moreover, the trend seems to be towards longer units - I can recall ten-car trains on the Southern made up of 5x2HAP (all those redundant driving cabs and guard's vans!), where now units of eight, ten, or even twelve cars are common (eg Classes 700 and 701, and of course the Stansted Express). The reduction in complexity, and greater capacity, by having fewer cabs seems to have won out over the flexibility to allow shorter trains at quiet times, or to make one good train out of two failures, that is possible with trains made up of shorter units.

Another issue is that is reducing with modern stock is the energy used in moving more stock around. Modern EMUs have energy recovery through regeneration. So although slightly more energy is used accelerating them up to cruising speed, much of that is recovered when slowing down, - the additional kinetic energy is returned to the supply for use by other trains in the vicinity (DC) or in the case of ac traction, available to be returned to the national grid supply.

 

[6Gman]

The advantage with the Southend route is that one end has a depot at Southend Victoria itself.

The West Anglia units would need to get to/from Ilford.

And traincrew to get it there (and back).

And paths.

 

[Dr_Paul]

It’s been explained in the past that when trains such as 8 car SWT 455s were routinely split between the peaks to run as 4 car for a few hours until mid afternoon, the overheads in terms of additional drivers, shunters for the electrical coupling, and the timetabling difficulties of all the extra ECS moves to and from depots on already busy routes, meant that leaving the trains as 8 cars all day on Mon-Sat quickly became the preferred method of operating.

That's right; what savings would be made in running four-car trains would be negated by the additional expense and inconvenience incurred by dividing them. I made the point in that discussion that it is rare to see a single four-car unit running out of Waterloo these days, whereas the past 4-SUBs on the suburban services would run as single units off-peak and at the weekends, and that coupling or uncoupling them at Waterloo was commonplace. I did see a single 455 the other week in the afternoon and thought how unusual it looked. The trend towards longer trains at all times is being reinforced by the introduction of 10-car 701s out of Waterloo.

 

[F Great Eastern]

That's right; what savings would be made in running four-car trains would be negated by the additional expense and inconvenience incurred by dividing them. I made the point in that discussion that it is rare to see a single four-car unit running out of Waterloo these days, whereas the past 4-SUBs on the suburban services would run as single units off-peak and at the weekends, and that coupling or uncoupling them at Waterloo was commonplace. I did see a single 455 the other week in the afternoon and thought how unusual it looked. The trend towards longer trains at all times is being reinforced by the introduction of 10-car 701s out of Waterloo.

There have been a few more single 455s recently even during peak on some SWR services which has been very interesting to say the least!

 

[norbitonflyer]

it is rare to see a single four-car unit running out of Waterloo these days

Not as rare as it used to be.........

On the subject of overcapacity, a colleague used to go on about the double decker buses that went past his house all evening, and thought London Transport should use minibuses at such times. No amount of argument that this would require extra garage space at night, or that the buses might be picking up crowds further down the route (eg chucking out time at the Bingo) would persuade him.
So I asked him why he drove a car with five seats to work, rather than buy a Smart Car for that purpose, and only use the big car for family outings. "I can't afford to run two cars, or have I got the space to park them"

İ rest my case.

 

[Sleepy]

Stansted Express arrivals at Liverpool Street that are lighter loaded always have around 80% of passengers getting off from rear 6 coaches as those with luggage dislike walking very far along the platform at Stansted when boarding.

 

[saismee]

I think the "wasting electricity" point is interesting. Extra coaches would increase weight and power consumption, but it's also extra intertia which allows for coasting for longer periods, and extra energy gained from regenerative braking. I'd imagine the electricity consumption from uncoupling, accelerating into a siding, then reversing and re-coupling for the next peak would end up consuming more electricity, especially on routes with fewer stops.

 

[AM9]

I think the "wasting electricity" point is interesting. Extra coaches would increase weight and power consumption, but it's also extra intertia which allows for coasting for longer periods, and extra energy gained from regenerative braking. I'd imagine the electricity consumption from uncoupling, accelerating into a siding, then reversing and re-coupling for the next peak would end up consuming more electricity, especially on routes with fewer stops.

Which is what I posted in #38 above. The returns are less with DC but they still negate any presumed gains by running less stock on services.

 

[The exile]

It's also a service that you wouldn't want people left behind for lack of capacity. Better to be safe than sorry.

This should apply to every service.

 

[trebor79]

On a related note, I was on a Stansted to Norwich service yesterday afternoon. 4 car 755. It was almost full leaving Stansted and there were people standing Cambridge to Ely.

Part of the problem is there's nowhere to put large suitcases that don't fit in the overhead rack. We were one such culprit with no option, but to largely block access to a bay with 2 big suitcases. Eventually I persuaded my wife it was fine to ignore the "do not block this door" sign as it was highly unlikely the driver was going to need to leave the van whilst the train was moving.

 

[The exile]

On a related note I was on a Stansted to Norwich service yesterday afternoon. 4 car 755. It was almost full leaving Stansted and there were people standing Cambridge to Ely.
Part of the problem is there's nowhere to put large suitcases that don't fit in the overhead rack. We were one such culprit with no option but the largely block access to a bay with 2 big suitcases. Eventually I persuaded my wife it was fine to ignore the "do not block this door" sign as it was highly unlikely the driver was going to need to leave the van whilst the train was moving.

Sure the driver would have been very understanding of your blocking their only emergency exit!

 

[DynamicSpirit]

Stansted Express arrivals at Liverpool Street that are lighter loaded always have around 80% of passengers getting off from rear 6 coaches as those with luggage dislike walking very far along the platform at Stansted when boarding.

You'd have thought any (semi-)regular travellers would realise they have to walk the same distance either way - it's just, whether they choose to walk it at Stansted or at Liverpool Street. And if they have arrived at the platform to board their train with more than a minute or two to spare, they actually save themselves time by walking down the platform to board the train - since it means they'll be able to exit quicker once they arrive at the other end.

 

[AF91]

This should apply to every service.

It should but what I'm getting at is the Stanstead Express trains would have a greater percentage of customers with time critical connections so it's easier to justify a greater degree of spare capacity on the trains.

 

[DynamicSpirit]

I dont think trains are too long per se, but they do carry fresh air around at times off peak, but this preferable to short formed etc during the peak, then being too crush loaded, leave passengers behind. i dont think there easy solution to this, to keep units long enough in peaks but not too long off peak.

Running all trains the same full length is often friendlier to passengers: It means that the train always stops at the same place, so special entrances for cyclists and people needing level boarding are always at the same place. And there's no danger of someone standing in the 'wrong' part of the platform and so discovering only as the train pulls in that they have to run 50m down the platform to catch it. (Obviously not stopping in the same place isn't really an issue for terminal stations like Liverpool Street and Stansted if trains always run to the end of the line and that's where then entrance is - but it may apply to intermediate stations)

 

[fandroid]

My understanding is that the 444 and 450 units on SWR are all maintained by Siemens and paid for on a unit-mileage basis. That would impose an unnecessary extra cost for running empty units around in multiple.

I could well be wrong here. I'm sure someone with more knowledge will immediately confirm or otherwise.

 

[DynamicSpirit]

I am always tickled by suggestions of splitting XC trains at the extremes of routes to save a couple of units. The delay and cost involved with the shunting as well as the difficulties in keeping sets in the right place in disruption makes it seem not worthwhile.

That incidentally makes me wonder about the decisions of other TOCs to order shorter units that often run coupled together. For example, you often see two coupled units running on HS1. Especially when you're talking High Speed services where about half the end carriage is out of bounds to passengers, that seems a huge waste of capacity at busy times compared to just running a fleet of all-10-car trains - and this discussion seems to indicate that the net benefits of splitting are at best marginal.

My understanding is that the 444 and 450 units on SWR are all maintained by Siemens and paid for on a unit-mileage basis. That would impose an unnecessary extra cost for running empty units around in multiple.

I could well be wrong here. I'm sure someone with more knowledge will immediately confirm or otherwise.

No idea whether you're correct, but I would observe the class 444 and 450 services, when coupled together, still allow through access to the entire train to passengers, and the space taken up by the unused driver's cabs is tiny, so for those particular unit types, there's almost no loss of passenger capacity involved in having shorter units run in multiple, compared to one longer unit.

 

[norbitonflyer]

I persuaded my wife it was fine to ignore the "do not block this door" sign as it was highly unlikely the driver was going to need to leave the van cab whilst the train was moving.

Highly unlikely indeed - but if he did need it, he wouldn't have time to ask nicely.

No idea whether you're correct, but I would observe the class 444 and 450 services, when coupled together, still allow through access to the entire train to passengers, and the space taken up by the unused driver's cabs is tiny, so for those particular unit types, there's almost no loss of passenger capacity involved in having shorter units run in multiple, compared to one longer unit.

There are two other factors involved with SWR's Desiros.
Some of the routes the 450s work are busy enough to require 12-car trains. But some stations on other routes can only accomodate eight cars. So the optimum length of unit is the highest common factor of 8 and 12, which is 4.

Ten cars are necessary on the main line to Southampton and Bo9urnemouth, but the Weymouth electrifcation was done on the cheap, and can't supply power to operate ten-car trains (*), so five have to be detached at Bournemouth.

(*) during the Olympics, when the sailing compeition was held at Weymouth, special arrangments were made for a few 10-car services, but special scheduling was required to ensure no other trains were drawing power from the same section at the same time

 

[JamesT]

That incidentally makes me wonder about the decisions of other TOCs to order shorter units that often run coupled together. For example, you often see two coupled units running on HS1. Especially when you're talking High Speed services where about half the end carriage is out of bounds to passengers, that seems a huge waste of capacity at busy times compared to just running a fleet of all-10-car trains - and this discussion seems to indicate that the net benefits of splitting are at best marginal.

You’re buying quite a few more carriages to run everything as full length units like that. At several million quid per carriage, that’s an expensive convenience. Some of the newer rolling stock acquisitions have gone down that route as they have passenger numbers that justify it, would HS1 in 2003?

 

[357]

Eventually I persuaded my wife it was fine to ignore the "do not block this door" sign as it was highly unlikely the driver was going to need to leave the van whilst the train was moving.

Sure the driver would have been very understanding of your blocking their only emergency exit!

Highly unlikely indeed - but if he did need it, he wouldn't have time to ask nicely.

And this is why if I hear a suitcase being pushed against the cab door I refuse to move my train until it's been moved.

I once had someone removed from my train as they put their case back there as soon as we started moving.

 

[The Planner]

My understanding is that the 444 and 450 units on SWR are all maintained by Siemens and paid for on a unit-mileage basis. That would impose an unnecessary extra cost for running empty units around in multiple.

I could well be wrong here. I'm sure someone with more knowledge will immediately confirm or otherwise.

This is also why you see a lot of units in Camden for LNWR, same applies from Siemens.

 

[Iskra]

Rather than reducing train lengths off peak, why not just take some trains out of the timetable at quiet times?

Note: I am talking about high frequency commuter routes only here and a sensible service should still remain. Please don’t over-react and think I’m extolling Beeching Mk2…

 

[Bletchleyite]

Rather than reducing train lengths off peak, why not just take some trains out of the timetable at quiet times?

Note: I am talking about high frequency commuter routes only here and a sensible service should still remain. Please don’t over-react and think I’m extolling Beeching Mk2…

This is generally done (or rather peak extras are added at busy times).

 

[saismee]

Which is what I posted in #38 above. The returns are less with DC but they still negate any presumed gains by running less stock on services.

I skim-read to make sure I wasn't repeating anyone but I must have missed yours! Completely agree about the returns being negligible to none.

No idea whether you're correct, but I would observe the class 444 and 450 services, when coupled together, still allow through access to the entire train to passengers, and the space taken up by the unused driver's cabs is tiny, so for those particular unit types, there's almost no loss of passenger capacity involved in having shorter units run in multiple, compared to one longer unit.

And the FLIRTs used on StEX have a great deal of space taken by the electronics due to the low-floor design. Running these in multiple would be very detrimental to capacity (755 triple traction, for example).