Why is Crossrail so late?

Yellow Fang

Legendary Member
Location
Reading
And how much can we blame Sadiq Kahn?
Alright, we've had Covid, but it is four years overdue. I can see the tracks at Reading. It's a wonder they're not getting rusty. Sadiq Kahn gets some criticism for it, but he's not a project manager, so what can we blame him for?
 

Rocky

Reprobate
Let’s blame him for all sorts of vanity projects - new bridges, water cannons, giving public money to his lover and pushing the idea of an airport in the Thames estuary. Oh, hold on that was the other chap
 

Eric Olthwaite

Insert witty self-deprecating description here
It's a unique project with no reliable comparators. In my experience of planning for projects with such characteristics, plans and timescales are very largely complete guesswork, and anybody who tells you otherwise is almost certainly bullshitting.
 

steverob

Veteran
Location
Buckinghamshire
Like many of the above posters, for a project this complex, while it would be nice to blame a politician for the reasons it was not delivered on time or on budget, they rarely have anything to do with it apart from signing the contract at the start and cutting the ribbon at the end.

But if you really want to blame the Mayor anyway, it's worth noting that Crossrail has been under construction for coming up to twelve years now (and planned for much longer previous to that). While five of those have been under a Labour mayor, the other seven of them under a Conservative mayor - you know, whatshisface, never see much of him these days, must be camera shy or something?

As for the real reasons, I believe while the construction part of the project did run slightly behind schedule (the tunnelling and lines were pretty much all built, but the stations were late being completed), they weren't the main cause. The bigger issues all seem to revolve around the signalling, the software and the testing; or at least that's what I've read.
 
OP
Yellow Fang

Yellow Fang

Legendary Member
Location
Reading
It's a unique project with no reliable comparators. In my experience of planning for projects with such characteristics, plans and timescales are very largely complete guesswork, and anybody who tells you otherwise is almost certainly bullshitting.
There are other railways and other undergrounds. There was the Docklands Light Railway, the Jubilee Line and the London Overground. What's different about this one?
 
OP
Yellow Fang

Yellow Fang

Legendary Member
Location
Reading
Like many of the above posters, for a project this complex, while it would be nice to blame a politician for the reasons it was not delivered on time or on budget, they rarely have anything to do with it apart from signing the contract at the start and cutting the ribbon at the end.

But if you really want to blame the Mayor anyway, it's worth noting that Crossrail has been under construction for coming up to twelve years now (and planned for much longer previous to that). While five of those have been under a Labour mayor, the other seven of them under a Conservative mayor - you know, whatshisface, never see much of him these days, must be camera shy or something?

As for the real reasons, I believe while the construction part of the project did run slightly behind schedule (the tunnelling and lines were pretty much all built, but the stations were late being completed), they weren't the main cause. The bigger issues all seem to revolve around the signalling, the software and the testing; or at least that's what I've read.
What's special about the signalling and the software? Are they trying to automate it all?
 

Bromptonaut

Rohan Man
Location
Bugbrooke UK
There are other railways and other undergrounds. There was the Docklands Light Railway, the Jubilee Line and the London Overground. What's different about this one?
Scale.

DLR is light rail and has been delivered in instalments over the last 30 years. As part of redevelopment of Docklands infrastructure was probably a component of various sites being created rather than being overlayed on stuff that's existed for years. It utilised quite a bit of extant/former heavy rail infrastructure. All the stations were above ground. It was not without its own problems in the early years.

The Jubilee line was originally conceived as the Fleet Line and for most of its length took over what was formerly the Stanmore arm of the Bakerloo line. Only Baker Street to Charing Cross was new. The later extension to Stratford was a very troubled project, not least in terms of signalling.

The Overground is, for the most part, a linking of long standing lines.

Crossrail is a completely new build underground from west of Paddington to East of Liverpool St, linked to the existing networks and having to navigate all the obstructions and hazards of tunnelling under the inner city. It will utilise full size trains running at very tight headways. Comparing it to any recent 'new' lines in the UK is bananas/elephants territory. The nearest obvious comparator is the the RER system in Paris.
 
OP
Yellow Fang

Yellow Fang

Legendary Member
Location
Reading
It sounds like most the heavy engineering is done. Why is the signalling such a problem? At this end, it goes from Reading, Twyford (a twee market town on the outskirts of Reading), Maidenhead, the Slough of Despond and Paddington. In other words, parallel to the line that is already there. How many of tracks does it cross between Paddington and Liverpool Street Station?
 

Bromptonaut

Rohan Man
Location
Bugbrooke UK
I think that's right getting the signalling right, together with some of the infrastructure at the connection stations in Central London which are Tottenham Court Road, Farringdon and Bond Street, is the issue. There's plenty of leads on further detail via Google or with Wikipedia as a start point.

The magazine Modern Railways has a monthly update on the project.
 

steverob

Veteran
Location
Buckinghamshire
It sounds like most the heavy engineering is done. Why is the signalling such a problem? At this end, it goes from Reading, Twyford (a twee market town on the outskirts of Reading), Maidenhead, the Slough of Despond and Paddington. In other words, parallel to the line that is already there. How many of tracks does it cross between Paddington and Liverpool Street Station?
It's because it's a mish-mash of different systems. Crossrail has the central underground section that is built specifically for it, which has the most modern up to date signalling, which it HAS to have in order to be able to safely run 24 trains per hour (a frequency normally only acheived on "metro" style railways, not with more traditional rail), but out west it has to share lines with GWR and out east with Greater Eastern services, which have their own requirements and technology that has been around for a lot longer. Getting the three to talk to each other and work successfully without bringing faults into the other's domain isn't quite as easy as maybe they originally envisioned it turns out, and that's caused some of the delay.

There's a reasonable article about that here: https://www.railengineer.co.uk/crossrails-signalling-challenge/
 
OP
Yellow Fang

Yellow Fang

Legendary Member
Location
Reading
It's because it's a mish-mash of different systems. Crossrail has the central underground section that is built specifically for it, which has the most modern up to date signalling, which it HAS to have in order to be able to safely run 24 trains per hour (a frequency normally only acheived on "metro" style railways, not with more traditional rail), but out west it has to share lines with GWR and out east with Greater Eastern services, which have their own requirements and technology that has been around for a lot longer. Getting the three to talk to each other and work successfully without bringing faults into the other's domain isn't quite as easy as maybe they originally envisioned it turns out, and that's caused some of the delay.

There's a reasonable article about that here: https://www.railengineer.co.uk/crossrails-signalling-challenge/
24 trains per hour, really?

"Crossrail trains will share tracks with Great Western Railway and Heathrow Express services out of Paddington to Reading and Heathrow, and with Great Eastern services from Liverpool Street to Shenfield."
What, I thought they were building additional tracks.

"So, as well as CBTC, Crossrail trains have to be fitted with ETCS, TPWS and AWS, with automatic changeover between the systems at the appropriate point."

Actually, I know a bit about this, because I maintain train simulators, but I am not so much bothered about which buttons you should press when, but whether the component works at all. ETCS is the European system, boo, hiss. The ATP system, is an older system dating back several decades. The AWS system is even older. It goes 'ping' when the train over over a magnetic block in the tracks, but only if the next signal is green. If the signal is not green it makes a loud noise and a sunflower lamp comes on. I am not sure how the TPWS system works. I know if you jump a red the train comes to a stop and a message sounds in the cab to call the signaller, in which case you had better start worrying about your mortgage. My company provided the simulators for Crossrail several years ago, but they are not ones I maintain. I suppose it would be better to read the manuals for this stuff when travelling to Plymouth, rather than reading the great works of literature, but as far as I am concerned, it's software.
 

steverob

Veteran
Location
Buckinghamshire
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