I think the short answer to the question in the topic title is 'Yes'.
The slightly longer answer is 'Yes,
for the same passenger numbers'.
For very short journeys with stops 5 minutes apart (I'm thinking London Underground with this one) and passengers not being on the train for more than about 30 minutes you can cram more pepole in a short train by making them stand, hopefully only for about 5 minutes as somebody will get off at the next stop (or the one after) allowing passengers standing to grab the seats before the next load of passengers board. For slightly longer journeys, up to 1 hour (example here being Cardiff to Merthyr) but still with stops every 5-10 minutes you need toilets and more seats so can cram fewer passengers in the same length of train. If passengers will be on the train for more than an hour, then seat pitch needs to be increased to improve legroom (and luggage space) so again less passengers can fit on unless you make the train longer and if stops are over 10-15 minutes apart then nobody should be having to stand either.
Also peak passenger numbers need considering, not just averages. Suppose that a short journey is operated by short trains with 200 seats and an average passenger count of 150.
Indeed, as noted above there should be a time limit above which nobody should be expected to stand. So if there's a gap between stations of more than 15 minutes, then the busiest train of the day between those stations should still have a few seats free and nobody standing.
Also breakdowns happen, whether of the train itself or infrastructure problems. On a local service, standing for 20 or 30 minutes on the following train is just about acceptable. On a journey of several hours, standing on the following train is not really acceptable.
Not alot you can do about breakdowns though, expect encouraging operators to try and win golden spanners for looking after the trains. Well, that and having a number of 'hot spare' units available at strategic points to pick up a diagram in that unfortunate case.
It seems to me that considered nationally, that we have plenty of short trains but not enough longer ones.
Suppose as an example, that a TOC▸ perceives a need for some new 4 car or 5 car trains. I would prefer that they make use of some of the EXISTING voyagers or IETs▸ , and that new full length trains be built to replace some of these.
As a currently relevant example, it is now becoming fairly widely admitted that the order for GWR▸ IETs included too many 5 car units. It has also been suggested that people like me should not criticise this because it is a done deal and cant be altered.
If another TOC wants perhaps a dozen 5 car IETs, then in my view another 6 full length units should be built for GWR and 12 half length units transferred to where needed.
The 6 nine car units should be cheaper to build than 12 units each of five cars. 54 vehicles instead of 60 for a start, a 10% saving.
I agree with that; if anything there's more than enough Voyagers and 5-car 125mph Hitachi units in existance and on-order given the recent
MML» and
WCML▸ announcements. Similarly I don't think any more diesel 125mph units (that includes anything with a diesel engine that's capable of over 110mph, unless the class 801 single engine plus its fuel is significantly lighter than batteries to do the same job of keeping the 'hotel power' going for hours if the unit is stuck) should be ordered beyond what is currently known about.
Only have to buy one 88 seat coach to replace the centre driving coaches especially if they are still in production. The two driving coaches could be stored for spare parts as these two coaches with cab and kitchen should have the most wear and tear.
That's an interesting idea, but I can't imagine the thought of writing off two end vehicles for each new set created would look good on its own. Hitachi will want the same return on those vehicles that they are currently expecting for the next 35 years or so. Though if they could be reused for another order then that might work.
I think something similar should happen to the Voyagers and Meridians once the MML and WCML TOCs are done with them, because they're not so new scrapping some of the driving vehicles would be less unpallatable. Basically the 220s would have their centre cars inserted into 222s (assuming the two types are similar enough) and 221s merged with other 221s. For the class 800s, I have an idea to make the trains longer without scrapping driving vehicles and without building any more diesel engines.
- Complete the electrification to Oxford and Bristol (via both routes)
- Order 14 sets of 7 AT-300 EMU▸ intermediate vehicles; no diesel engines just some batteries for emergency hotel power (unless the diesel engine would be significantly lighter)
- Remove the 3 intermediate vehicles (with diesel engines) from 14 5-car bi-modes and insert them into 14 other 5-car bi-modes
- Insert the new intermediate EMU vehicles into the 'orphaned' 2-car sets created in the previous step
- Net result: 28x 5-car bi-mode become 14x 9-car EMU and 14x 8-car 'super power' bi-mode with 6 diesel engines.
- Deploy the 14x EMUs on Oxford/Bristol/Cardiff services
- Cascade the 14x 'super power' bi-modes to CrossCountry, allowing any Voyagers left at 5-car after the reformation suggested above to move to the Cardiff-Nottingham service
2x5s, or 2x anything, can increase specific carriage overloading and thus decrease comfort because of the limited ability to move carriages.
That certainly applies to stock without unit-end gangways, but not to something like a class 158. I would therefore not entirely agree with broadgage on this point:
I am in general opposed to the building of any more short trains, unless some truly exceptional need for these can be demonstrated.
I don't think there's a problem with short units that have unit-end gangways, a 75-110mph top speed and no large 'crumple zones' or kitchens etc. that waste space if doubled up (although I think we have enough suburban type units with wide doors for stopping services for the time being). With something like the class 158s, you can run a long train on the busy part of the route and drop coaches for the quieter bits to save fuel (or give through services to more places) That doesn't work nearly so well if passengers can't move between units without getting off the train (in which case they are effectively having to change train). Thus I consider the large number of 125mph 5-car units being built now to be madness, especially once you consider that if a route has 125mph linespeeds it's obviously quite busy or it'd never have justified the investment in linespeed upgrades.