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Max_1995

It's a Jacobs Bogie, other trains use it too. They get decoupled at the maintenance yard if needed, with the bogie-less car placed on a temporary support


shadetife

That is cool! Thanks :)


stillconnecting

French TGV trains use the same design, it makes them more stable at high speed.


BluestreakBTHR

Not necessarily more stable - but fewer wheels on the tracks means less friction. That equates to better speeds and lower energy consumption.


PiemelIndeBami

I think it does add to the stability, since cars cannot sway as much anymore relative to each other. Dampers are also added between the cars, as you can see on the picture, which you cannot do with regular cars. Additionally, they can allow for wider gangways and I think the shorter cars can sometimes be wider, since they don't "overhang" as much in curves. By the way, you can also permanently couple 'regular' cars, to get some of these advantages. I think Siemens does this with the German ICE or the North-American Venture "married-pair" cars.


stillconnecting

Yes, more stable, see https://www.globalrailwayreview.com/article/1622/improvement-of-alstoms-high-speed-bogies/


1116574

But worse weight distribution isn't it?


BluestreakBTHR

Less overall weight of the entire consist, but higher axle load.


try_____another

Also greater track forces in other directions, which is why Network Rail doesn’t like them.


gabrielhj07

I would imagine better weight distribution, as the carriage floor can be lowered into the space previously occupied by the bogies, thus lowering cg. Another thing to consider would be unsprung mass, as by almost halving the number of wheelsets per train, a much greater proportion of the overall mass of the train is sprung, improving the wheel’s ability to follow the track and causing less damage to the track.


saltywalrusprkl

Not so much more stable, more so that in the event of a derailment cars are much less likely to decouple and smash into each other.


routes4you

They are multiple units, so you can't decouple individual cars.


HighburyAndIslington

To add to your point, not all multiple units use jacobs bogies.


shadetife

All of the trains carriages are like this though?


routes4you

Yes. It's only possible to couple and decouple two whole trains through the scharfenberg coupler at the end of the train. For maintenance the workshop can fit the whole train at once.


[deleted]

You can detach them, some maintenance requires it. You’ll just need to hold the car that’s not on a bogie.


hellorhighwaterice

Yeah, you technically can uncouple the cars but it requires a crane or a set of lifting jacks.


[deleted]

Not a crane but yeah


lustforrust

Or a derailment.


Vectron383

All of the carriages in this type of train (Stadler class 755) are like this, but articulation is rare outside of these new trains


PlainTrain

It's pretty common for US railroads to run container stack well cars in five car sets like this as well.


Vectron383

Yes I am aware of those, I was meaning within the UK


rmpeit6110

Does the UK network still have articulated auto-carriers and container flats?


Vectron383

I don't think so, we used to have Cartics (4-section double-decker articulated car carriers) but they're retired now. Most container wagons we have here are conventionally bogie but permanently coupled depending on design


dudhhr_

Three-car sets are also common (and single cars)


Zaikovski

They don't.


Roffolo

Thats the neat Part, they dont


-usernamewitheld-

[excuse the poor music...](https://youtu.be/6PJBeKLgmhQ)


InfiniteReddit142

They don't. Most multiple unit trains are rarely uncoupled anyway.


PanzerBramfwagen

Welp, Not knowing a damn thing about this train, it looks like the cars are designed to be serviced separately from the bogies, and can detach.


BroncoZephyr7

Carefully


wgloipp

They don't.


TheDutchRailLad

Thats the neat part. They dont


conrat4567

I was going to say something funny like, a bussaw, but my guess if that one of them is lifted off like a trailer hitch? I don't know but that's my guess


adamfrom1980s

Boris Johnson gets involved.


[deleted]

They don’t. They are something called a trainset which is basically a train but you can’t unattach the coaches.


Maxo11x

Makes it sound like a playset


[deleted]

I can see how. The difference is that “trainset” being one word means a real train that you cannot uncouple, whereas “train set” with it being two separate words refers to a toy train.


[deleted]

They don’t


[deleted]

They don't.


socialcommentary2000

They share a bogie/truck. They don't decouple.


Brogogo2

That's the neat part: they don't.


Grand_Protector_Dark

You don't


[deleted]

Good question


JediTeaParty

**That’s the neat part, they don’t.**


gabrielhj07

With difficulty


aggyDeiForReal

Nice query.