New train platforms - design flexibility

[Rhydgaled]

Just wondering how flexible current train design platforms are (eg. Aventra, Civity, AT200 etc.). I know the Aventra is being produced with 2 and 3 doors per-side, what other variations are possible?

• Vehicle-end doors (like a class 175)?
• Unit End Gangways (UEGs) (we know this is possible on AT200s, but can Aventras and Civities have them)?
• DMU versions of Aventra and AT200?
• Vehicle length variations (I think the AT300 is offered in 20m 23m and 26m versions)?
• Window-size (this is actually want prompted this topic, I was wondering if the minimum width and height were specified in an invitation to tender, would the builders need to design a new product from scrach?)

I ask because I am wondering if a TOC/government made a quite-specific specification, would the train builders all be able to offer something and compete for the contract? Is a DMU with UEGs, 23m vehicles, vehicle-end-doors and windows no smaller in any dimension than the largest current UK train* possible within the existing new train platforms?

* I would be interested to see measurements of all train windows, if anyone knows were to find them. My guess is that the mrk3 and class 442 have the biggest windows, but I could be wrong.

 

[Peter Mugridge]

I'd suspect the 700s have bigger windows than the Mk3*?



*442s and Mk3 are the same thing.

 

[MCR247]

Voyagers are pretty big

 

[superalbs]

Voyagers are pretty big

As are Class 143/Class 144 windows, can't imagine they'd hold up very well in a crash.

 

[Rhydgaled]

I'd suspect the 700s have bigger windows than the Mk3*?

Voyagers are pretty big

I think we need actual window width and height measurements to answer the question of which windows are bigger. I can't tell by looking at them because the aspect ratios are different; both Voyagers and 700s appear to have squarer windows than a 442/Mrk3, but I can't tell whether that is because:

a. the newer units have taller windows the same width as a Mrk3 (in which case the new units have bigger windows) or
b. the newer units have narrower windows the same height as a Mrk3 (in which case the Mrk3s have bigger windows) or
c. neither the width nor the height of the windows are the same

As are Class 143/Class 144 windows, can't imagine they'd hold up very well in a crash.

Again, Pacer windows are squarer and again I'm not sure which dimension(s) are different to a Mrk3. I think is the blank wall between windows is smaller on a Pacer though compared to modern air-conditioned units.

Anyway, this talk of which window is bigger isn't answering the other half of the question, which is whether the window size (and other features) of new trains is fixed for each design family.

 

[D365]

Don't forget that whilst you state an Aventra unit can be offered with two or three doors per carriage side, the Class 345 (three doors per side) consists of 23m carriages, whilst the Class 710 (two doors) is the more 'traditional' 20m.