Sliding vs Double Plug Doors - What's better?

TrainViation · 12 Jul 2026

I've noticed recently about different styles of train door, for example the sliding doors on the more modern 80Xs and refurbished ScotRail HST sets, compared to the plug style doors on other trains like the 158s and 170s.

Is there anything inherently different about the two styles of doors? Is one of them safer than the other? And why are train manufacturers switching over to them?

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Towers · 12 Jul 2026

Sliding ‘pocket’ doors are generally considered to be more reliable and are faster to operate, however the obvious downside is that they require somewhere within the bodyshell to disappear into when open. A notable use of this design is Hitachi’s 80x fleets, all of which have them. One drawback is the potential for debris to block the runners, as well as for the doors to become rough in operation with age.

Plug doors can be more prone to poor operation with age, in particular taking ages to close or struggling when the train is sat on cambered track as is often the case at railway stations across the network.

TrainViation · 12 Jul 2026

Towers said:
Sliding ‘pocket’ doors are generally considered to be more reliable and are faster to operate, however the obvious downside is that they require somewhere within the bodyshell to disappear into when open. A notable use of this design is Hitachi’s 80x fleets, all of which have them. One drawback is the potential for debris to block the runners, as well as for the doors to become rough in operation with age.

Plug doors can be more prone to poor operation with age, in particular taking ages to close or struggling when the train is sat on cambered track as is often the case at railway stations across the network.

I’d hope that the new fleet of ScotRail trains for example, get sliding doors, as the main routes they will work in Fife for example, a lot of the platforms for example are curved and definitely on a camber such as Burntisland. As you say, the sliding doors are better with age than plug doors.

superkev · 12 Jul 2026

Im old enough to remember when during one bad winter Network south East said they wouldn't buy anymore trains with sliding doors due to dirt and ice constantly blocking the door tracks. Didn't I read somewhere thus was a problem last winter with the Hitachi trains.
K

Strathclyder · 12 Jul 2026

I strongly suspect the trend of new ScotRail EMUs having plug doors (which started with the 334s through the 380s to the 385s) will contiune with the order for the 318/320 replacement stock in the next couple years. As things stand presently, the 318s/320s are the only EMUs with sliding doors left in the fleet since the 314s were withdrawn.

Russel · 12 Jul 2026

What was the logic behind fitting the IET fleet with sliding doors?

physics34 · 12 Jul 2026

Cheaper, more reliable, safer?

sharpener · 12 Jul 2026

Towers said:
Sliding ‘pocket’ doors are generally considered to be more reliable and are faster to operate, however the obvious downside is that they require somewhere within the bodyshell to disappear into when open. A notable use of this design is Hitachi’s 80x fleets, all of which have them. One drawback is the potential for debris to block the runners, as well as for the doors to become rough in operation with age.

Plug doors can be more prone to poor operation with age, in particular taking ages to close or struggling when the train is sat on cambered track as is often the case at railway stations across the network.

Plug doors have better aerodynamics when closed and a train with them has less drag than sliding doors.

JamesT · 12 Jul 2026

Russel said:
What was the logic behind fitting the IET fleet with sliding doors?

That’s what Hitachi offered? They used the same type of doors on their existing products such as some models of Shinkansen.

TRAX · 13 Jul 2026

JamesT said:
That’s what Hitachi offered? They used the same type of doors on their existing products such as some models of Shinkansen.

It is indeed Hitachi's preferred door system.

357 · 13 Jul 2026

superkev said:
Im old enough to remember when during one bad winter Network south East said they wouldn't buy anymore trains with sliding doors due to dirt and ice constantly blocking the door tracks. Didn't I read somewhere thus was a problem last winter with the Hitachi trains.
K

When I worked for GA, we would sometimes have problems during snow with the 360s. Ice would form on the side of the train stopping the doors from opening.

Recessio · 13 Jul 2026

Electric operated plug doors are slower than electric sliding doors (for examples of fast sliding doors, see a Thameslink 700, an Southeastern 376 or Overground 378, or most Underground stock.) This can make a big difference on metro services with lots of stops.

Older air operated doors (sliding or plug) are dead slow: the old 442s on Southwestern, or even the 450 fleets when one ends up on a stopping service, you really notice the slower doors.

However on the Elizabeth line for example, the 345s have electric plug doors ,which are slightly slower than sliding, but this is mitigated by the platform screen doors which take about the same amount of time to open anyway so it doesn't affect the dwell times even on the intensive metro service in the core.

TrainViation · 13 Jul 2026

TRAX said:
It is indeed Hitachi's preferred door system.

Interestingly enough, Hitachi chose plug doors for their Class 385 for ScotRail. I'm not sure what other trains they have manufactured since though.

hwl · 13 Jul 2026

TrainViation said:
I’d hope that the new fleet of ScotRail trains for example, get sliding doors, as the main routes they will work in Fife for example, a lot of the platforms for example are curved and definitely on a camber such as Burntisland. As you say, the sliding doors are better with age than plug doors.

It very much sounds like you don't have experience of modern electrical powered plug doors e.g. Bombardier/Alstom Aventra family products, I'd recommend having trip down to south to experience them...

matchmaker · 13 Jul 2026

I may be wrong, but possibly the first use of plug doors in the UK was Class 303 unit 035, which had Dean plug doors as opposed to the Peters sliding doors as used on all the other 303 and 311. Apparently they weren't very reliable.

yorksrob · 13 Jul 2026

What's better ?

Slam doors obviously !

Between the choice given, plug doors as they don't ruin the window spacing.

Mikey C · 13 Jul 2026

The Networker doors are acceptably fast - much faster than the Desiro ones on the 350/450 etc - and seem to be pretty reliable. And the interior is way nicer than on similar trains with sliding doors, which spoil the area near them.

Another issue with older sliding door trains like the Mk3 EMUs is their tendency to rattle, and BANG when they go past another train.

py_megapixel · 13 Jul 2026

I'm sure I read somewhere that Network South East's units with sliding doors would sometimes get stuck in the winter because of water getting into the door tracks and freezing, and that this problem was a factor in their decision to order plug doors from the late 1980s onwards.

(can anyone corroborate?)

Sliding vs Double Plug Doors - What's better?

TrainViation

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Towers

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TrainViation

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superkev

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Strathclyder

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Russel

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physics34

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sharpener

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JamesT

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TRAX

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357

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hwl

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matchmaker

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