Merseyrail 777s - rather than additional units, should additional sections be ordered?

[Bletchleyite]

So, as per the reviews thread I spent a bit of time on 777s this weekend. One observation was that they handled high loadings quite well - but particularly on Sunday with the half frequency there were a lot of standees. This doesn't really seem aceptable when the only constraint is rolling stock, but 8 car sets may have been excessive.

I've long taken the view that Merseyrail should have considered longer trains (4-5 x 20m equivalent) and abandoning doubling up. So with the production line still being open, might it make sense for them to abandon all the complexity and cost of adapting things for doubled up 777s and gain capacity by ordering one or two more middle sections for each train (one section would give you a little longer than 4x20m, two slightly longer than 5x20m), and operate them only singly?

This would seem to save a fair bit of money so get more "bang for the buck", and mean that they don't need to worry about predicting flows. It might slow them down a bit, though.

It's notable that London Underground doesn't any longer do any form of portion working and has only ordered full length trains in recent years, with the DLR also changing to this.

 

[Kite159]

In hindsight they should have gone down the route of ordering fixed formation 120 metre units (similar to Great Northern with the 6 coach 717s replacing the 3 coach 313). No hassle with having to extend platforms to cope with paired up units being longer.

I guess the issue with ordering more coaches is they will end up with too many units and will probably have software related issues.

 

[Bletchleyite]

I guess the issue with ordering more coaches is they will end up with too many units

For now, yes. But would it perhaps be an option to do this instead of ordering extra units if any of the battery extensions proposed, such as Wrexham, Preston, Wigan or Helsby, become a reality? While only a few units are battery fitted, in my understanding all of them are capable of being so fitted (or with a pantograph and transformer, though not both as the transformer space is where the batteries go).

Before Stadler were even in the picture, I've long thought 5 x 20m units would have been the way to go, which would be the equivalent of adding two sections to the Stadlers. (I suspect the Loop tunnels are too tight for 24m vehicles). Very few services outside of the Grand National day actually need 6, it's always been a case that 3-car was too short for many services but 6 too long.