15 Carriage Hitachi Class 800

[J663738]

Checking for my times of my train home from Newport (Wales) on RTTs and saw that a 15 carriage GWR was on its way! I assumed it could be possible as the extra attached 5 carriages might just be empty and were being transported somewhere.
Sadly I video'ed the train as it left the platform and you guessed it, there was only 10 carriages.

This was the information, presume it was an error made when 5 car trains join together at Swansea, the software joined a 10 and a 5 by mistake.

https://www.realtimetrains.co.uk/service/gb-nr:P08499/2025-08-07/detailed#allox_id=1

Could they ever be configured like this?

 

[hexagon789]

Checking for my times of my train home from Newport (Wales) on RTTs and saw that a 15 carriage GWR was on its way! I assumed it could be possible as the extra attached 5 carriages might just be empty and were being transported somewhere.
Sadly I video'ed the train as it left the platform and you guessed it, there was only 10 carriages.

This was the information, presume it was an error made when 5 car trains join together at Swansea, the software joined a 10 and a 5 by mistake.

https://www.realtimetrains.co.uk/service/gb-nr:P08499/2025-08-07/detailed#allox_id=1

Could they ever be configured like this?

10 is the limit in normal service.

What's likely happened is a unit has been exchanged for another one and the original hasn't been deleted from the allocation, so it appears as a extra-long train!

We've seen similar with 22-car Pendolinos and 18-car Azumas appearing as allocations from time-to-time.

 

[zwk500]

Definitely a set-swap or allocation thing, pretty sure Swansea wouldn't take a 15-car!

I think long formations have operated on test and they are theoretically possible for rescue purposes but normally as @hexagon789 says 10 is the limit.

 

[Towers]

It’s mentioned before in a similar thread I’m sure, but there was a rather high profile 15 car formation during a rescue which failed at Southall some years ago, blocking just about everything!

 

[DarloRich]

it is clearly a data glitch.

 

[ExRes]

It’s mentioned before in a similar thread I’m sure

Change 'a similar thread' to numerous similar threads

 

[Peter Mugridge]

Change 'a similar thread' to numerous similar threads

These unit swaps must be the new datum plate for the forum!!

 

[brad465]

These unit swaps must be the new datum plate for the forum!!

I've sometimes wondered if the forum needs its own "Frequently asked questions" that are thread titles that recur a lot. This topic would be one of them.

 

[800001]

As had been stated many many times before, a set swap has taken place, this will of been done correctly in the back ground systems, but for some reason this takes times to work its way through to RTT, or sometimes does not happen.

You will never get more than a 10 car set allocated for passenger use.

You would only ever see a 14/15 or 18 car set when a failed unit needs rescuing which is still a very rare move to happen.

 

[Wilts Wanderer]

There were originally plans for 9+5 cars to attach for ECS moves between Stoke Gifford depot and Bristol Parkway but I believe the operational challenges and possibly also software issues meant this never happened. It would never be planned in passenger service, mainly because very few platforms could accommodate 364m of train!