7 ms·
Crossrail update on the Elizabeth line’s opening plans
- kingcharles 5y agoOff topic: I wonder why lines on London Transport don't capitalise the L in line? Elizabeth line, rather than Elizabeth Line? I would think "Line" is part of the name of the line?
- zeristor 5y agoRadio interference around Stratford being one issue it seems. Although it’ll be several months I thought before trains from Stratford will delve into the tunnels.
- bencollier49 5y agoIf they're struggling, they should put a shout out to UK radio hams to help diagnose the problem, they'd get loads of expert help.
- DocTomoe 5y agoOr maybe use something that's less dependent on radio frequency in one of the most populated, thus most frequency-polluted areas on Earth. Radio not always is the best choice, sometimes, cable is worth it.
- matthewmacleod 5y agoThe issue is interference at the interface between the train and the fixed signalling system. I’m sure you can appreciate the impracticality of building a train to signalling system interface that uses cables!
- zeristor 5y agoYou’d have to keep plugging it in.
- teget 5y agoShouldn't systems Like LZB or ETCS bei mostly protected against radio interference as only the Last section (centimeters) needs to bei transmitted wirelessly? Are they used in the line or did they opt for something else?
- jonp888 5y agoLZB uses cable loops. ETCS can use cable loops, but for full functionality a radio data connection is required.
- matthewmacleod 5y agoYeah, generally that’s true - it’s certainly not a long-range system. I’m not clear on what the actual problem is at Stratford, but I do know these systems can be quite sensitive and it can be tricky to ensure they operate reliably alongside each other. In the case of Crossrail the core (new tunnels) use CBTC signalling, I think based on Siemens TrainGuard - I think the specification of the project predates ETCS being proven as a viable solution for this particular kind of service. The services leaving Stratford to the East use TPWS/AWS in common with most services on the UK mainline network. The challenge is in the transition between the two systems, as I understand it - anything out of the ordinary and the train will of course come to an immediate halt.
- micropunk 5y agoAt first blush I can but thinking a bit further, these are electric trains right? And I know there have been "use your home electricity wiring for network" things around for decades... So can't they use the power cables for comms?
- matthewmacleod 5y agoIt’s an interesting idea and not without some merit. Some signalling systems do actually use the rails as a conductor already, although that’s just basically “is there are train on me or not” detection. I’m getting out of my depth, but I’m sure I’ve seen at least one signalling system that uses the track circuit as a data signalling channel to the train to provide in-cab signalling, so I’d guess it’s at least theoretically possible. I’d imagine it would have much the same challenges as radio in practice though - interference from poor connections and ambient noise, not to mention your channel is basically a massive antenna.
- heavenlyblue 5y agoAre you assuming radio hams are better at this than engineers getting paid for it?
- bencollier49 5y agoNo, but I am assuming that in their multiplicity and range of interests, they might quickly stumble on a solution in a way which a smaller population of well-trained professionals wouldn't. Reminds me of Feyerabend's "Against Method".
- ajb 5y agoThe entrance to the tunnels isn't where the interference of happening. The tunnels start at Liverpool Street What's a bit strange is that they've been running the same trains with passengers on from Liverpool Street through Stratford for more than 2 years, with passengers, as TFL rail. But I guess they had to upgrade the signalling around Stratford to work with the trains coming through the core, and that is still buggy
- zeristor 5y agoThe entrance portal is at Pudding Lane: https://anonw.com/2021/08/12/the-crossrail-tunnel-portal-at-pudding-mill-lane/ https://anonw.com/2021/08/12/the-crossrail-tunnel-portal-at-... From there the train will travel underground to the Liverpool St - Moorgate station. There’ll still be Elizabeth line trains travelling into Liverpool St station but there’ll be terminating. Fun fact there’s the large ABBA venue going up at Pudding Mill Lane. https://www.ourbow.com/abbas-virtual-comeback-show/ https://www.ourbow.com/abbas-virtual-comeback-show/ The things one misses when not commuting. No one has called it the ABBAtoir yet, but I’m waiting to see who’ll be the first to come up with that name.
- llimos 5y ago> The entrance portal is at Pudding Lane I think you mean Pudding Mill Lane? Pudding Lane was where the Great Fire of London started.
- tobylane 5y agoThe current service is to Liverpool Street high level, staying on one signalling communication system. The problem is about changing to a different one for the core (which includes Whitechapel before Liv St). They had a similar problem on the other side but it was resolved easier.
- blibble 5y agoit's quite amusing to hear Liverpool Street's mainline railway station described as high level when it's buried 30ft underground it was originally buried so that it could connect up with the Metropolitan Railway (today's metropolitian line on the London Underground) this was so that in 1875 the Met could use the mainline railway station as terminus (whilst their own was under construction)
- antihero 5y agoWhen I lived in Stratford I always had lots of really weird intermittent problems with WiFi and 4G. Probably not related but would be interesting if it was
- midasuni 5y agoAfter the recent publicity testing, I was hoping to be riding it before Easter, now it looks like even the core part will take until June or even later. It’s hilarious this is so many years behind schedule. It’s also why I don’t think nuclear is the answer - as a country the U.K. can’t do big projects.
- Reason077 5y ago> ”it looks like even the core part will take until June or even later.” If it goes beyond June then it will be extremely embarrassing for all involved. They’ve repeatedly promised “first half of 2022”, and reaffirmed that very recently.
- mytailorisrich 5y agoThe UK can no longer do nuclear, anyway. New projects (inc. Hinckley C) all rely on foreign tech and foreign contractors to lead the projects.
- agd 5y agoRolls Royce are developing small nuclear reactors. Doesn’t rely on foreign tech or contractors.
- mytailorisrich 5y ago'developing' is not the same as 'having'. They still have some know-how based on legacy nuclear power plants and military reactors (which I'm guessing is what Rolls-Royce will build on) but at the moment they cannot build a civil nuclear power plant from scratch by themselves. This is actually tricky beyond the design and certification. You need the whole industrial capacity as well. For instance, the French government has repeatedly made sure that a specific steel mill in the country remains operational because it is the only one large enough and with the required equipment to manufacture the huge steel domes encasing the nuclear reactor cores...
- kmlx 5y ago> it looks like even the core part will take until June or even later. > It’s hilarious this is so many years behind schedule it’s 4 years behind schedule, 2 of those were covid. not bad, not good. > It’s also why I don’t think nuclear is the answer - as a country the U.K. can’t do big projects. crossrail was the biggest european construction project. huge undertaking, and with only 4 years behind schedule. for a western project this is pretty good actually. hinkley point c is just 6 month behind schedule. but usually if you’re building something huge in a western country then expect huge delays.
- cm2187 5y agoDo we know when the link Heathrow-Paddington is meant to open? Along Abbey Wood to Reading?
- matthewmacleod 5y agoHeathrow to Paddington is effectively already open (and has been for some time) - the existing service that’s branded as “TfL Rail” is the precursor to the “Elizabeth Line” branded service, using the same train and track. The same applies to Reading to Paddington. After the Paddington to Abbey Wood service settles down most of the Heathrow and Reading services will start to run through the tunnels as well, and that becomes the full service.
- deleted 5y ago[deleted]
- lostlogin 5y agoI’ve only watch the first season of the BBC documentary on the line, but it was great. https://www.crossrail.co.uk/news/crossrail-documentary-the-fifteen-billion-pound-railway/ https://www.crossrail.co.uk/news/crossrail-documentary-the-f...