New tube for London stock

This is complete speculation, but could it be to do with a miscalculation of the number of wheelchair bays?

I am surprised it is further back than the S7 stopping posts. Would they be shorter in overall length than S7's

Also the T/Op's final visual alignment to the mark on 24TS is via a side porthole window similar to 92TS, 95/96TS. S stock doesn't have that and alignment to a left hand chevron is to the edge of the left hand windscreen, a different viewing angle that puts the chevron further forward in front of the train. So one would not expect S stock and 24TS stop markers to be in the same position.

Given that every other recent new stock's production version has differed from the prototypes it's almost certain the answer to this will be yes

Probably. But the greatest learning is likely to come from the trials on the line itself - a simulation can never be completely accurate

It's almost certainly too early to say. It will depend on what modifications will be required, iirc those for the 2009 stock were so extensive that the prototypes were scrapped as it was cheaper to build two more production trains.

This is the most likely explanation.

Anyway, what I actually came on to post today is I hear - and this is from encoded jungle drums - there /may/ be a NTFL train delivery via channel tunnel "this weekend".

I know no more than that - it was vague "this weekend".

So far I can see no obvious GB main line paths in RTT - but this been the case with other new main line stock past deliveries as a anti grafiti precaution.

If nothing appears, don't shoot the messenger, as all I am doing is relaying a coded message.

I'd not heard that but entirely plausible.

Whatever, no way is it exceptional for any large production run of anything at any time to have test / trial vehicles.

Build 1000 vehicle contract - build 1 or 2 test pieces and scrap it is peanuts - 0.1% of the build total and if it offers overall cost savings enabling early try outs, it actually saves.

What is an exception is to find out about them. And if they do not have numbers then the trainspotting fraternity can't match them up with anything, can't report them other than unidentified, and when they are not there next visit, no-one is any the wiser...... but it is one of those things the numerologists get hot under the collar about.


Way back in time (1978) when I was a National Bus Co engineering trainee I got two extended visits to Workington Leyland National bus factory - and one part of the place was littered with all sorts of bits and pieces from complete shells downwards but never intended to run or were production line abortions. In 1980s a post student temp. job was at the Rootes Ryton plant building Talbot Horizons - and there were a number of never intended to be sold bodies there too.

Bus building on a 1970s production line or 1980s cars is no different to Derby's or anywhere else modern train building production line.

The original Siemens brochure was released with announcement of the contract award in 2018. It appears that it was based on claims at the time that the new trains would not feature a cab, but would have a wandering train attendant aboard, DLR style. This was on the assumption that new signalling would be installed before the first train arrived for service. Priorities have changed over the life of the contract, and new signalling remains unfunded. It was assumed that a temporary cab would take the place of four seats, but it seems that this has become six seats. It was also decided that a permanent cab would be required for conventional driving on the Piccadilly Line west from Rayners Lane, and on the Bakerloo Line due to the proportion of line north of Queens Park. The revised seating figures therefore reflect incorporation of a cab into the train design, a feature that was agreed some years back!

I believe that's why a rebuild of Holborn is required when the resignalling goes ahead.

I have just noticed that Lithium Ion Batteries are being used - presumably for the Emergency Auxilaries etc plus the "get you home" traction power.

Is this the first use of significantly sized batteries of this type on Tube stock?

The Siemens idea for a Central Line version of the Piccadilly Line train is to lengthen it by two cars to make an 11-car train. This adds an additional wheeled car and a wheel-less car. However, it makes the formation too long for current 8-car platforms, so the cab cars will be shortened by around 1.5 metres to be similar in length to the other wheeled cars in the train. Assuming that the door spacing is retained throughout the train for standard parts, this means that the bay behind the cab will be reduced from five seats a side to only two seats a side, the same as the ends of the wheel-less cars. The timing of such an order is unclear given CLIP plans for the present fleet.

The current Victoria Line trains were built to take advantage of the larger tunnels on the line, and the gentle curves, so they cannot be transferred over other tube lines. The same would probably be done with any replacement stock, and perhaps also for the similar Jubilee Line. There is also the complication of Platform Edge Doors on the latter line which suit current door spacing. It has been suggested that during the stock change-over period, the PEDs will be adapted to treat the single end doors as an extra wide double door, so that the replacement trains need only have double-doors spaced to the current door patterns. If these were to the Central Line plans, then they would also feature an additional double doorway at each end, which might need further modification to the PEDs unless the end doors were cut-out at the JLE tunnel stations. That may be acceptable with only 8 seats a side beyond the current end PED opening.

Good point burkitt but I don't think the scale drawings of a Picc train rule it out. I admit, it would be close. link p.15. There is also little spare space between the two double doors to allow those to be spaced any closer! The bogies on the wheeled cars are concealed under seats, which prevents the doorways moving any closer to the car ends.

Perhaps the 96TS replacement stock when it's needed could be a similar layout to 96TS... Just how essential are through gangways after all? Or is that too simplistic I wonder?
Perhaps this is a thread branch for Jubilee.

Siemens did preliminary work on new trains for the four lines in the contract, and planned a standard train apart from the length of the cab cars. Funding restrictions meant that the current Central Line trains needed life extension works before new trains could be afforded. That seems to remain the plan, although progress on the CLIP works appears slow. Could a new funding agreement mean that CLIP is abandoned in favour of a new fleet?

The Jubilee Line became the highest priority fleet replacement in 2020, along with the Northern Line upgrade from transferred surplus trains, link p.31. Could it be substituted for the Central Line fleet in the Siemens contract, or would a new contract be required? Probably a question for a commercial lawyer!

Comparing the planned Central Line train door spacing with the current Jubilee Line trains, with an adjusted stopping mark, there is only a maximum of 700mm difference in the centre-points, treating end single doors as a wide double-door. But looking at restrictions on the placing of doors on the Picc train, as mentioned above on wheeled cars, and also wheel-less cars spacing to end of car and between the two doorways, I now doubt a solution could be found.

I wonder how long a project to replace all the PEDS would take, given that the ones on Crossrail took far longer than expected! They are, of course, twice the length. Should Charing Cross Jubilee station be reopened during the conversion closure, to provide connections to the Northern and Bakerloo lines for Waterloo? That would require renovation of the heritage assets there.

Bermondsey and Southwark might close a single platform for an out-of-hours conversion trial, with passengers needing to override and return in the opposite direction, perhaps also after the blockade for the opposite platform conversion. This does assume that the complete old fleet is available before the blockade, and the complete new fleet is available after. The central platform at North Greenwich could be usefully retained for reversal of the eastern shuttle service, then being closed for conversion when a through service returns.

How great a ventilation problem would it cause, if we just got rid of the wretched things? It might be worth while upgrading the ventilation to future-proof the line.

Perhaps that would involve long-term thinking; not a priority in our short-term world.