Why 1973 Stock first?

[EJD799]

Why is the 1973 Stock being replaced by 2024 Stock before the 1972 Stock even though the 1973 Stock is slightly newer and significantly more reliable?

 

[bramling]

Why is the 1973 Stock being replaced by 2024 Stock before the 1972 Stock even though the 1973 Stock is slightly newer and significantly more reliable?

They carry more people and the Piccadilly Line is considered to be a more important part of the network, and the new trains will represent more of a capacity improvement. There’s also an element of planning blight with the possibility of the Bakerloo Line being extended.

 

[etr221]

Would it be possible to use the 1973 Stock on the Bakerloo Line once it is replaced on the Piccadilly Line?

 

[JonathanH]

Would it be possible to use the 1973 Stock on the Bakerloo Line once it is replaced on the Piccadilly Line?

It doesnt fit, being 6 slightly longer coaches than the 7 coach trains on the Bakerloo Line - I think this is an informed post on the subject for reference - https://www.railforums.co.uk/thread...ns-inspiro-london.214811/page-31#post-6694737 and https://www.railforums.co.uk/threads/1972-tube-stock-replacement.220529/#post-5246709

Also this about how Stonebridge Park isnt equipped for them - https://www.railforums.co.uk/thread...ns-inspiro-london.214811/page-17#post-6326862

 

[Mawkie]

Would it be possible to use the 1973 Stock on the Bakerloo Line once it is replaced on the Piccadilly Line?

Apart from the gauging issues, did you miss the bit where they are so life expired they're literally being scrapped before our eyes.

 

[Silent]

Why is the 1973 Stock being replaced by 2024 Stock before the 1972 Stock even though the 1973 Stock is slightly newer and significantly more reliable?

Significantly??? I use the Bakerloo daily and think it's works far better than it looks like it works, it still does it job and waiting times usually aren't overly long even if tfl says Minor delays a lot.

 

[A60stock]

The !973 stock have covered far more mileage and have been much more intensively used across 50 years, vs the fairly leisurely life of the 1972 mk Ii stock, most of which do not go past Queens Park. Even those going all the way to Harrow cover far less distance than the 1973 do end to end. The trains are also much more busier given the line goes to Heathrow.

The above reasons basically highlight why the Piccadilly is a far busier line than the Bakerloo in its current form. Don't get me wrong, the 72ts should have long gone by now and I imagine had replacement begun for both stocks at least 10-15 years ago, the 72ts MIGHT have been replaced first.

However, tfl have let both reach 50 and replacement is far more urgent, therefore, the slight age gap between the two no longer plays a factor and it comes down to other factors, described above.

On another note, I'm no engineer, but from using both lines, the 73ts seem like they are struggling and almost on their last legs, the motors do not sound smooth on many trains. The 72ts seems very strong and (asides from the fact the technology and ambiance is clearly older) the motors seem to be healthier and better sounding.

 

[Silent]

The !973 stock have covered far more mileage and have been much more intensively used across 50 years, vs the fairly leisurely life of the 1972 mk Ii stock, most of which do not go past Queens Park. Even those going all the way to Harrow cover far less distance than the 1973 do end to end. The trains are also much more busier given the line goes to Heathrow.

The above reasons basically highlight why the Piccadilly is a far busier line than the Bakerloo in its current form. Don't get me wrong, the 72ts should have long gone by now and I imagine had replacement begun for both stocks at least 10-15 years ago, the 72ts MIGHT have been replaced first.

However, tfl have let both reach 50 and replacement is far more urgent, therefore, the slight age gap between the two no longer plays a factor and it comes down to other factors, described above.

On another note, I'm no engineer, but from using both lines, the 73ts seem like they are struggling and almost on their last legs, the motors do not sound smooth on many trains. The 72ts seems very strong and (asides from the fact the technology and ambiance is clearly older) the motors seem to be healthier and better sounding.

First time I’ve seen someone agree with the opinion that the 73ts motors sound more work like I do from my recent, but not frequent, journeys on them. 73ts look better but feel worse from when I’ve rode on them.

 

[A60stock]

I imagine this in part may also be due to the fact that the 72s have had life extension work done on them where-as the 73ts can be kept running at the bare minimum due to their imminent replacement

 

[Julia]

I imagine this in part may also be due to the fact that the 72s have had life extension work done on them where-as the 73ts can be kept running at the bare minimum due to their imminent replacement

I'm pretty sure the original plan *was* to replace the 1972Mk2s first, but they were allowed to degrade to the point where they needed urgent structural work on a much shorter timescale than new stock could be delivered in. Having had that work done, they were then deemed good for another ten years or so and dropped in priority behind the 1973s.

With a radical new design such as the articulated 2024ts it would have been lower risk to replace a smaller fleet on a less busy line first and shake out all the gremlins before attempting the Piccadilly, but circumstances intervened...

 

[Silent]

I'm pretty sure the original plan *was* to replace the 1972Mk2s first, but they were allowed to degrade to the point where they needed urgent structural work on a much shorter timescale than new stock could be delivered in. Having had that work done, they were then deemed good for another ten years or so and dropped in priority behind the 1973s.

With a radical new design such as the articulated 2024ts it would have been lower risk to replace a smaller fleet on a less busy line first and shake out all the gremlins before attempting the Piccadilly, but circumstances intervened...

Hopefully the 24ts wouldn’t be the next 92ts. I’m pretty sure it wouldn’t as the structural layout is unique but a lot of things on it seem tried and tested on TfL and some other modern rolling stock.

 

[danielnez1]

I'm pretty sure the original plan *was* to replace the 1972Mk2s first, but they were allowed to degrade to the point where they needed urgent structural work on a much shorter timescale than new stock could be delivered in. Having had that work done, they were then deemed good for another ten years or so and dropped in priority behind the 1973s.

With a radical new design such as the articulated 2024ts it would have been lower risk to replace a smaller fleet on a less busy line first and shake out all the gremlins before attempting the Piccadilly, but circumstances intervened...

Would the 2024 Bakerloo stock need the floating coach design that is being used on the Picadilly?

Hopefully the 24ts wouldn’t be the next 92ts. I’m pretty sure it wouldn’t as the structural layout is unique but a lot of things on it seem tried and tested on TfL and some other modern rolling stock.

The 2024 Stock is based on the Siemens Inspiro platform, so will hopefully incorporate as may of the tired ant tested components and build practices as possible.

 

[Nym]

It doesnt fit, being 6 slightly longer coaches than the 7 coach trains on the Bakerloo Line - I think this is an informed post on the subject for reference - https://www.railforums.co.uk/thread...ns-inspiro-london.214811/page-31#post-6694737 and https://www.railforums.co.uk/threads/1972-tube-stock-replacement.220529/#post-5246709

Also this about how Stonebridge Park isnt equipped for them - https://www.railforums.co.uk/thread...ns-inspiro-london.214811/page-17#post-6326862

Thanks for quoting them to save me re-typing

TL;DR, it doesn't fit.

Although the lifting roads (37/38) at Stonebridge can fit a 4 car 72, so a 3 car 73 would be fine. It just couldn't get there.

 

[Silent]

Would the 2024 Bakerloo stock need the floating coach design that is being used on the Picadilly?


The 2024 Stock is based on the Siemens Inspiro platform, so will hopefully incorporate as may of the tired ant tested components and build practices as possible.

Yes, aren't the 1972 stock longer than 73ts as a whole train and the floating coaches on 24ts fit air con equipment under them I think.

 

[Snow1964]

Would the 2024 Bakerloo stock need the floating coach design that is being used on the Picadilly?

The plan was a follow on order for Bakerloo of identical trains (except for colour of few interior fittings)

The options for Central line are based on an eleven section version (rather than 9 section) with slightly shorter vehicles.

At moment orders are for Piccadilly (base quantity like for like number of trains) plus extra for enhancement from 24 to 27 trains per hour. Another batch to increase frequency to 30-36tph (which also needs full resignalling) hasn't yet been ordered.

The increase in capacity is about 10% for new trains, and another 12% for frequency uplift to 27tph. If ever a high frequency (like Victoria line) happens then capacity is 60% up on today.

 

[Thirteen]

I imagine having the same rolling stock across multiple lines also means long term cost saving as well.

 

[A60stock]

I imagine that to an extent, having the same rolling stock will be difficult across all the deep level lines due to the various ages of the current stock.

I would guess that the groupings are likely to be the Bakerloo, Central/W&C and Piccadilly using the 24ts, and the Jubilee, Northern and Victoria using whatever is available come their time. However, bringing the Victoria line in line with other lines will be difficult as it would mean retiring the 2009ts early or having to continue with 95/96ts for an extra 5-10 years.

Of particular interest will be the way the Jubilee line replacement will be managed, due to the PEDs on the newest section of the line (unless the door alignment of the new trains are kept the same.........unlikely)

 

[Thirteen]

I imagine that to an extent, having the same rolling stock will be difficult across all the deep level lines due to the various ages of the current stock.

I would guess that the groupings are likely to be the Bakerloo, Central/W&C and Piccadilly using the 24ts, and the Jubilee, Northern and Victoria using whatever is available come their time. However, bringing the Victoria line in line with other lines will be difficult as it would mean retiring the 2009ts early or having to continue with 95/96ts for an extra 5-10 years.

Of particular interest will be the way the Jubilee line replacement will be managed, due to the PEDs on the newest section of the line (unless the door alignment of the new trains are kept the same.........unlikely)

I suspect the plan is not to have the same stock per se since the Central/W&C was always going to be slightly different but variants of the same stock so the process is simpler.

The 2009 stock could be retired early if need be, TfL did that with the D Stock in order to have the S Stock be used across the various SSL but it'd be difficult to cascade it anywhere else since it's ATO.

 

[A60stock]

By the point of retirement of the 2009 stock, assuming it's retired early and in line with the 95/96ts, I am not really sure there would be any further use for them (if the 72s and 92s are already gone by then).

When I say same stock, I meant variant of the 24ts, like how the S Stock has variants.

 

[Thirteen]

By the point of retirement of the 2009 stock, assuming it's retired early and in line with the 95/96ts, I am not really sure there would be any further use for them (if the 72s and 92s are already gone by then).

When I say same stock, I meant variant of the 24ts, like how the S Stock has variants.

By cascaded, i don't mean to other parts of the Tube network as they're too wide but ship them off to the Isle of Wight.

 

[Silent]

I imagine that to an extent, having the same rolling stock will be difficult across all the deep level lines due to the various ages of the current stock.

I would guess that the groupings are likely to be the Bakerloo, Central/W&C and Piccadilly using the 24ts, and the Jubilee, Northern and Victoria using whatever is available come their time. However, bringing the Victoria line in line with other lines will be difficult as it would mean retiring the 2009ts early or having to continue with 95/96ts for an extra 5-10 years.

Of particular interest will be the way the Jubilee line replacement will be managed, due to the PEDs on the newest section of the line (unless the door alignment of the new trains are kept the same.........unlikely)

I think the ped’s also become life expired so they would be replaced with new stock as well. Me and a lot of people would miss the 96ts sound but the same applies to the 72/3ts I guess. The last dc motor tube trains.

It’s also weird picturing jubilee line with a standardised tube stock because I grew up with the jle being opened, it standing out as well as the trains, especially more before the 09 and s stock. When central also looked futuristic but somewhat older and 95 looked like 96 ts but much blander to me as a kid.



== Doublepost prevention - post automatically merged: 8 Aug 2025 ==

I wouldn’t be surprised if 09ts is replaced early or late, depending when the 95/6ts are replaced. Because the ventilation doesn’t work well on the 09ts I can only imagine really bad passenger perception of them if all the other tube lines had air conditioning.

 

[61653 HTAFC]

By cascaded, i don't mean to other parts of the Tube network as they're too wide but ship them off to the Isle of Wight.

A lot of time and money has just (well, in the last five or so years) been spent on the Island Line to accommodate the larger D-stock derived 484s: platforms raised, depot modifications, work to Ryde tunnel (though not as much as one might think)... There's no way they'll go back to using deep level stock. Once the 484s are life-expired there'll be some other solution, be that second hand tramcars from somewhere, conversion to a busway, or wholesale closure- as who knows what sort of state the island, the country, the wider world will be in by then.

 

[Nym]

I think the ped’s also become life expired so they would be replaced with new stock as well. Me and a lot of people would miss the 96ts sound but the same applies to the 72/3ts I guess. The last dc motor tube trains.

It’s also weird picturing jubilee line with a standardised tube stock because I grew up with the jle being opened, it standing out as well as the trains, especially more before the 09 and s stock. When central also looked futuristic but somewhat older and 95 looked like 96 ts but much blander to me as a kid.

Two or three points.

1992TS is DC motored, and there's no intent to AC Traction the W&C Line.
1996TS has DC motors, just not for traction.

A transitionary period for PEDs would be required, it would not be palatable to close the line to fit them and change over the fleet.

 

[Silent]

Two or three points.

1992TS is DC motored, and there's no intent to AC Traction the W&C Line.
1996TS has DC motors, just not for traction.

A transitionary period for PEDs would be required, it would not be palatable to close the line to fit them and change over the fleet.

Oh yeah, I forgot the 92 had DC traction, but it doesn't have the same type of noise as the old metro cammell trains. 92 ts would be missed for there unique motors and design I think, even though not the best build quality. They were built in a time where vehicle design seemed to change a lot and computers were being used more for designing and operating them.

 

[pokemonsuper9]

A lot of time and money has just (well, in the last five or so years) been spent on the Island Line to accommodate the larger D-stock derived 484s: platforms raised, depot modifications, work to Ryde tunnel (though not as much as one might think)... There's no way they'll go back to using deep level stock. Once the 484s are life-expired there'll be some other solution, be that second hand tramcars from somewhere, conversion to a busway, or wholesale closure- as who knows what sort of state the island, the country, the wider world will be in by then.

S-trains? (Life expired S stock converted into the Class 485s and then the company that converted them goes bankrupt)

 

[Dstock7080]

S-trains? (Life expired S stock converted into the Class 485s and then the company that converted them goes bankrupt)

Class 485s were of course ex-LT Standard Stock

 

[61653 HTAFC]

S-trains? (Life expired S stock converted into the Class 485s and then the company that converted them goes bankrupt)

Perhaps, but that's very much a matter for its own thread. I've got into quite enough trouble with the mods on here, and it nearly always starts with an innocent correction of someone else's mistake!

 

[announcements]

== Doublepost prevention - post automatically merged: 8 Aug 2025 ==

I wouldn’t be surprised if 09ts is replaced early or late, depending when the 95/6ts are replaced. Because the ventilation doesn’t work well on the 09ts I can only imagine really bad passenger perception of them if all the other tube lines had air conditioning.

I wonder how a mid-life refurb would look for an '09 stock. Could they rip out a seat per car to fit air con equipment? Would be much welcome!

As I've commented on in another thread, while I get the arguments to replace the '73 stock first, the one thing it isn't in desperate need of is air conditioning compared with lines such as the Central and Victoria.

 

[computerSaysNo]

Have they fixed the issue of the heat spiral for the deep tubes then?
(First train air con takes in mild air, spits cold air into carriage and warm air into tunnel; warm air remains in the tunnel as it has nowhere else to go. Second train takes in warm air and spits cool air into carriage and hot air into tunnel. By the third train the air in the tunnel is hot and the air con can only cool it to "mild" which is what you'd have had if none of the trains had had air con in the first place.)

 

[Recessio]

Have they fixed the issue of the heat spiral for the deep tubes then?
(First train air con takes in mild air, spits cold air into carriage and warm air into tunnel; warm air remains in the tunnel as it has nowhere else to go. Second train takes in warm air and spits cool air into carriage and hot air into tunnel. By the third train the air in the tunnel is hot and the air con can only cool it to "mild" which is what you'd have had if none of the trains had had air con in the first place.)

The new trains generate less heat than the old ones (mostly due to being lighter, and having regenerative breaking rather than rheostatic). TfL's choice was therefore to either let the tunnels/stations be overall slightly cooler than currently, or they could now fit the trains with AC and still "only" generate as much heat in the tunnels/stations as the current 1972/1973 stocks does.

Therefore, the tunnels shouldn't be any hotter than they are right now with the current stock. Furthermore I think the piston effect should do a reasonable job at cycling air in and out of stations. There's also trials of improved station cooling that looked promising and can hopefully be rolled out in future.