New tube for London stock

On the Elizabeth line at least, the tunnels all include an emergency walkway and do not feature electrified rails so the risks are not as great

The walkways I saw around Liverpool Street when I worked there were level with the bottom of the train doors so better for emergency evacuations.

Canal is new construction. Must admit I had overlooked that in my post about Victorian build- I commute on Thameslink but on the MML and core bits and seldom think of the new GN bit.

The presence of DC traction rails is not directly relevant to the current requirements for new single tunnels - they have to have walkways anyway - the concern is evacuation per se.

The old Thameslink Midlland City route to Moorgate did have single line tunnel sections by definition but not as first constructed. When Barbican and Moorgate area was rebuilt, some structures split the Up and Down lines over a length that exceeds more than a couple of carriages and prevented side egress. That is why end gangways were on 317s (end corridors) and 319s (escape doors) else they would have cabs like 150s and 321s respectively.

Yes, BR continued to use non gangway carriages to Moorgate after the area was rebuilt, but that was permitted only to continue until existing stock could be replaced. There had been early comment in an incident about a DMMU fire ; I forget which incident it was now.

If that Moorgate area rebuild had taken place rather later than it did, they would have to have provided escape walkways.

700s do not have end gangways - not even escape gangways like 717s do - because there are either walkways(GN bits) or the locations on the MML where clearances are tight (between St.Pancras and Kentish Town) the long unit nature of 700s mean there is always one part of the train in the clear. Obviously it is double track, so the other track is available for escape, the clearance issue is on the tunnel wall side and very VERY close in some places (take a look on the southbound track immediately on entering the tunnels south of Kentish Town).

One of the escape plans for 700s is evac to another 700 drawn up side by side. There are special kits to do that that I /think/ each 700 carries at least two of somewhere in the train.

345s evac on the Eliz line area bit different as the route is essentially all single bore tunnels for practical purposes and with walkways.

Drifting a bit, channel tunnel has walkaways. I have been on those, as I took part in the original 373s evac exercises.

In January, Siemens Mobility completed all works at the test track in Wildenrath in Germany, including installation of third and fourth rail power upgrades and building of a platform for one-person operation. Testing will start on the track to ensure all upgrades are functioning correctly ahead of the first train arriving there for dynamic testing in the summer.

In March, the first-in-type driving motor car body shell was completed by Siemens. The car body is now ready to enter the painting process. This keeps us on target for the first train to be completed and transferred to the test centre in Wildenrath to start commissioning tests this autumn.

Our depot migration plans is under review after a change to our wheel lathe delivery caused knock-on impacts, leaving our depots programme misaligned to the train introduction dates. We are working through mitigation options to minimise any schedule and cost impacts.

[Finance Report - Period 1, 2023/24 - Management results from 1 April 2023 – 29 April 2023]

The 2014 NTfL feasibility study recommended the most efficient upgrade of the four lines would involve a continuing build of a single train design, but financial problems led the initial order to be for the Picc, with options for the other lines. Currently Government support for TfL runs to March 2024, but negotiations continue for a long-term transport investment settlement like the settlements given in the Budget to eight regions outside of London, the Cities Region Sustainable Transport Settlements (CRSTS) which extend to 2031-32. Currently a case is being built for a contract extension with Siemens for the Bakerloo trains which must be ordered in 2026. Beyond that is really long-term planning!

Here's another picture that shows the whole thing:

This was reported up thread and the picture clearly shows that a train is complete and moving.

That is by design, 5 bogie cars, 4 floating

Why is the first build numbered unit 71?

Indeed, the first S Stock delivered to London was:
21099/100 as an S7, just 9 trains from the highest S8 number.

So I don't pay for Twitter so I can see around (what feels like 2 tweets) 100 tweets before I get rate limited for the rest of the day. Does look v weird with cars, looks like its floating

They stopped doing that after a couple of days.

Possible reason that the first train could be a de-icing train, which is numbered as the first build deicing train, so 24 deicing fitted trains out of the 94 which seems about right percentage based on current fleets.
Makes sense to build a deicing train as first off because of type testing requirements.

Deicing is carried on the middle car, no.5 of 9, or possibly flange lubrication, or track monitoring equipment. See table in RailEngineer