Future stock for the Island Line?

[Thirteen]

I realise that the Island Line has only had the Class 484s for 18 months or so but I wonder when that stock comes for replacement in the 2050s or 2060s, what will replace it?

My first thought was either the 2009 Victoria Line stock or S Stock but they might be very bad shape by the time they get cascaded. The other option might be custom stock based on either the NTfL or whatever replaces the Northern and Jubilee line stocks but that probably is too expensive.

 

[Egg Centric]

442s

 

[Speed43125]

442s

Surely it's 379s we'd be finding homes for by now?

 

[Bald Rick]

(picture shows a bus, with ‘Ryde Esplanade’ on the destination board. Not my pic!)

 

[JonathanH]

I realise that the Island Line has only had the Class 484s for 18 months or so but I wonder when that stock comes for replacement in the 2050s or 2060s, what will replace it?

It isn't obvious to me that D-stock would have been the expected replacement stock of you had posed this question about the 38-stock replacement back in the early 1990s.

 

[RobShipway]

It isn't obvious to me that D-stock would have been the expected replacement stock of you had posed this question about the 38-stock replacement back in the early 1990s.

I don't think it was expected the D-stock would have fitted through the tunnel or under the bridges for the Island line. I think the line did have to be lowered though in places, so the D-stock could fit?

The question would be is that do you allow trains to be used for 50 years elsewhere as in the class 483 units, before moving over to Isle of Wight or do you move over newer stock, that for some reason has been replaced sooner, such as the d-Stock that got used from the late 1970's until 2017?

I could be wrong, but I do't see the S7 and S8 stock being used on the Island, as I do not think that there is the infrastructure on the Isle of Wight, to cope with any of these trains. I think the next round of Stock in about 2054, would actually either be tram stock trains converted to be used on the island line in some form or brand new one off stock built for the IOW.

 

[QSK19]

I realise that the Island Line has only had the Class 484s for 18 months or so but I wonder when that stock comes for replacement in the 2050s or 2060s, what will replace it?

Maybe some of the 717s (with AC OHL ability removed) given that they’ve been built for tight clearances in the Moorgate branch? They’ll be 32-42 years old by then; so no doubt they’ll probably go off-lease as life-expired by the 2050-2060s. A new home on the Island Line would lead them into another chapter.

Without being that familiar with the Island Line, isn’t one of the train size determinants based on the Ryde Tunnel?

 

[RobShipway]

Maybe some of the 717s (with AC OHL ability removed) given that they’ve been built for tight clearances in the Moorgate branch? They’ll be 32-42 years old by then; so no doubt they’ll probably go off-lease as life-expired by the 2050-2060s. A new home on the Island Line would lead them into another chapter.

Without being that familiar with the Island Line, isn’t one of the train size determinants based on the Ryde Tunnel?

It is as to whether the trains can fit safely through the Ryde Tunnel. I believe that the class 484's just about fitted through Ryde Tunnel, but I think there was some work done to lower the track height in the tunnel so that the class 484's could fit. I am not sure on the size dimensions comparison between the class 484 and class 717, but I believe that the class 717 is taller in height?

 

[Gloster]

(picture shows a bus, with ‘Ryde Esplanade’ on the destination board. Not my pic!)View attachment 132579

Oh, we would love to have something so modern!

 

[Russel]

I thought someone had dug up a 10 year old thread when I saw the title!

 

[jon0844]

I think it was a myth that 'normal' trains couldn't fit in the Northern City Line section. 717s are the same as a 700, and before a 717 was built and sent down there for testing I am sure another train (I believe a LO 378) made a trip without issue.

The only thing that is customised for a train on the NCL is for the tripcock braking system, and that's soon going to be a thing of the past anyway.

 

[DanNCL]

I don’t think it’ll be deep level LU stock again as that would require all of the work that was done in 2021 to be reversed. There are multiple options. 717s are definitely a possibility but they’d need shortening. Shortened S Stock might be a possibility too. Less likely but not impossible that something could be imported from Metro systems elsewhere in Europe with a similar loading gauge if available at the right time. They’d need modifications but so would anything from the mainland.

It isn't obvious to me that D-stock would have been the expected replacement stock of you had posed this question about the 38-stock replacement back in the early 1990s.

Indeed. I imagine if I’d been alive back then and asked the same question I’d have replied with 73 or 83 stock, definitely wouldn’t have considered D stock!

I think it was a myth that 'normal' trains couldn't fit in the Northern City Line section. 717s are the same as a 700, and before a 717 was built and sent down there for testing I am sure another train (I believe a LO 378) made a trip without issue.

The only thing that is customised for a train on the NCL is for the tripcock braking system, and that's soon going to be a thing of the past anyway.

Also customised for the Northern City Line is the front evacuation doors.

73s have hauled Mark 1s and Mark 2s to Moorgate on test trains. 73s are a smaller loading gauge anyway but Mark 1s and Mark 2s aren’t.

 

[61653 HTAFC]

When the idea of D78s was first floated, the discussion over Ryde tunnel was about vehicle length as much as vehicle height. From what I can recall from the discussion at the time, anything much longer than the D78 carriages would struggle. I suspect that might be one of many factors that would prevent anything from the Desiro City (700,707,717) range from being an option.

As others have pointed out, the Northern City Line isn't particularly restricted clearance-wise. Indeed this was an aggravating factor in the Moorgate disaster, as the full height tunnels allowed the tube stock vehicles to over-ride each other.

== Doublepost prevention - post automatically merged: 9 Apr 2023 ==

I imagine if I’d been alive back then and asked the same question I’d have replied with 73 or 83 stock, definitely wouldn’t have considered D stock!

The 83 stock would have been ideal if new stock had been needed at a time when it was still around. In many ways it was a deep-level version of the D-stock that ended up being used three decades later.

 

[Irascible]

(picture shows a bus, with ‘Ryde Esplanade’ on the destination board. Not my pic!)View attachment 132579

That's about the right vintage to fit in! it'd be battery converted by someone who immediately went bust, of course.

 

[jon0844]

I think we can agree that there might need to be quite a bit more work to get that in the tunnel.

 

[D365]

I don't think it was expected the D-stock would have fitted through the tunnel or under the bridges for the Island line. I think the line did have to be lowered though in places, so the D-stock could fit?

Wrong and wrong.

Why are we speculating now?

 

[Gloster]

I would have thought the question should be ‘what will be operating the RRB to cover for the latest overrunning engineering blockade?’ It probably will be a Series 2 VRT, if we’re lucky.