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Transit Geek: England
I told a couple of people that I needed to write a LiveJournal post on the signalling system of the London Underground. There's actually quite a bit interesting about UK public transit, though...
Buses. They're everywhere. Transit for London is a lot like the T and runs buses like the T. But the cheapest and fastest way from Heathrow to anywhere very well might be a bus; the city of Oxford runs a direct bus over the 50ish miles to Heathrow for £16, plus buses from the city centre to London, plus some local buses. But there's also other bus companies. Near my hotel I could take the Oxford City 4 bus to the city centre, or I could take the Stagecoach 3 (10p cheaper). Both ran on similar, but coordinated schedules, so both buses ran "every 20 minutes" on Sunday but one or the other would appear after 10. Round-trip ("return") tickets are prevalent and cheap; a same-day return on the Heathrow bus is £17 (£1 more than the one-way ("single") trip).
Trains. I didn't quite figure out the national rail system while I was there. I was fairly clear that there was National Rail, but there were also at least three different passenger railroad brands I saw (First Great Western, Southern, Virgin). Trains, like buses, run on the left. The UK appears to have nationalised their rail system before it started to collapse, so there's not the intercity vs. commuter rail distinction here; the area around London also seems somewhat denser or clumpier than the US, so I could have taken a local train (which would have been about like a long commuter rail trip here) but instead I got an express that stopped at Reading, Slough, and London Paddington.
The FGW main line coming west out of London looked like a four-track main line, with a pair of local tracks and a pair of express tracks. Signals seemed pretty frequent but also slightly mysterious (I still haven't deciphered their diverging signal aspects). The line north to Oxford was only two tracks, but waiting at Oxford two fast intermodal trains blew past the station. A typical passenger train was 3-5 diesel rail cars; there's no separate engine, each car has its own engine. The trains I was on were all reasonably crowded (most of the transit was reasonably busy).
Underground. Transit for London has the best transit branding I've seen anywhere. Lots of ads. I now understand the famous gap (as in, "mind the gap") as well: if you built a subway station in the 19th century and you built it on a sharp curve, then it's kind of impossible for your straight subway cars to line up well with the platform, and the gap can be multiple inches wide. Not only third rail but a fourth insulated rail between the two main tracks; only guesses what it's for (low-voltage power? return?). Most stations were actively labyrinthine.
Signalling generally had two-head color-light signals, with single-block signaling with distant repeaters. "It's not strange, it's antiquated": if instead of translating three-position upper-quadrant semaphores into electrical lights you translated two-position lower-quadrant semaphores, you'd get the same effect. Home signals show green or red and have a white number plate with an "A", repeater signals show green or yellow (yellow means the home signal is red) with a yellow number plate with an "R". In a couple of cases the home signal is at the end of a platform so the repeater will be halfway through a station. Also in some cases two signals appear together, so you can see on a four-head signal red (stop, no repeater aspect), green/yellow (next home signal is red), or green/green (next two blocks are clear).
Buses. They're everywhere. Transit for London is a lot like the T and runs buses like the T. But the cheapest and fastest way from Heathrow to anywhere very well might be a bus; the city of Oxford runs a direct bus over the 50ish miles to Heathrow for £16, plus buses from the city centre to London, plus some local buses. But there's also other bus companies. Near my hotel I could take the Oxford City 4 bus to the city centre, or I could take the Stagecoach 3 (10p cheaper). Both ran on similar, but coordinated schedules, so both buses ran "every 20 minutes" on Sunday but one or the other would appear after 10. Round-trip ("return") tickets are prevalent and cheap; a same-day return on the Heathrow bus is £17 (£1 more than the one-way ("single") trip).
Trains. I didn't quite figure out the national rail system while I was there. I was fairly clear that there was National Rail, but there were also at least three different passenger railroad brands I saw (First Great Western, Southern, Virgin). Trains, like buses, run on the left. The UK appears to have nationalised their rail system before it started to collapse, so there's not the intercity vs. commuter rail distinction here; the area around London also seems somewhat denser or clumpier than the US, so I could have taken a local train (which would have been about like a long commuter rail trip here) but instead I got an express that stopped at Reading, Slough, and London Paddington.
The FGW main line coming west out of London looked like a four-track main line, with a pair of local tracks and a pair of express tracks. Signals seemed pretty frequent but also slightly mysterious (I still haven't deciphered their diverging signal aspects). The line north to Oxford was only two tracks, but waiting at Oxford two fast intermodal trains blew past the station. A typical passenger train was 3-5 diesel rail cars; there's no separate engine, each car has its own engine. The trains I was on were all reasonably crowded (most of the transit was reasonably busy).
Underground. Transit for London has the best transit branding I've seen anywhere. Lots of ads. I now understand the famous gap (as in, "mind the gap") as well: if you built a subway station in the 19th century and you built it on a sharp curve, then it's kind of impossible for your straight subway cars to line up well with the platform, and the gap can be multiple inches wide. Not only third rail but a fourth insulated rail between the two main tracks; only guesses what it's for (low-voltage power? return?). Most stations were actively labyrinthine.
Signalling generally had two-head color-light signals, with single-block signaling with distant repeaters. "It's not strange, it's antiquated": if instead of translating three-position upper-quadrant semaphores into electrical lights you translated two-position lower-quadrant semaphores, you'd get the same effect. Home signals show green or red and have a white number plate with an "A", repeater signals show green or yellow (yellow means the home signal is red) with a yellow number plate with an "R". In a couple of cases the home signal is at the end of a platform so the repeater will be halfway through a station. Also in some cases two signals appear together, so you can see on a four-head signal red (stop, no repeater aspect), green/yellow (next home signal is red), or green/green (next two blocks are clear).
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Trains: Actually, France has left-hand running as well, bizarrely enough. The main line out of Paddington is, I think, six-track out as far as Airport Junction for Heathrow, then goes down to the more traditional British standard up/down-fast, up,down-slow layout. Look up the Beeching Report for possibly the most convulsive event to hit the railways in their history (early 1960s). National Rail is kind of a weird umbrella brand run by all the passenger rail service franchisees (particular rail routes are franchised, while the actual infrastructure maintenance and operation is all handled by Network Rail). A legacy of the Major government, which decided that a single nationalised British Rail run as a public service was close to Communism.
Underground: Four-rail system: One (the outer rail) is at +420V, the centre rail's at -210VA, for a total of +630V. It's a weird system and dates from years ago, when it was found necessary to reduce the voltage of individual rails to reduce galvanic action between the rails and the cast-iron tunnel linings on the deep tube lines. Signalling is effectively track circuit block, with two-aspect signalling and drivers running "at sight" - i.e. they should always be able to stop within sight of a signal once it's in sight. Some hard to see signals have repeaters (yellow/green aspects rather than red/green), and overrunning of stop signals is prevented by trainstops. London Underground runs the trains but no longer maintains the infrastructure, which is now subcontracted out under a public/private partnership - a legacy of the Blair government, which decided that having a single nationalised London Underground run as a public service was close to Communism.
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De-nationalization...
To Branson's credit, I don't think you could get trains like "Bournemouth-Oxford-Birmingham" back in the British Rail days, and that particular train has proven jolly convenient. But I hear Virgin trains tend to get shafted because they own *none* of the track.
Re: De-nationalization...
The infrastructure (track, signalling, etc) is all owned by Network Rail, which was renationalised a few years ago after the private sector demonstrated its ability to make a complete pig's ear of running things. Oh, and after a couple of nasty high-profile accidents resulting from cutting corners on maintenance. Companies don't really juggle for space - paths and platform slots are all in theory worked out in advance and the signallers' working timetable doesn't care who's running the train, but it becomes a problem at places like King's Cross where (in theory) specific platforms are dedicated to specific companies. Two companies at a terminus = two sets of staff, two sets of everything. It's all pretty stupid.
What is a problem, though, is that as NR have to be agnostic when making signalling and routing decisions, there are a whole lot more cases where expresses get stuck behind local stoppers and thus end up running very late. In the past, a signaller would make a regulating decision and maybe loop the local for a few minutes to allow the express to overtake. Now, that's almost impossible if the trains concerned are run by different companies.
What the private sector's given us is lots of shiny new stock, a less reliable network, and an enormous loss of talent. Thanks, Tories!
Re: De-nationalization...
I remember the accidents, especially the massive one near Paddington; hadn't realized track maintainence had been re-nationalized as a result. But the effect of enforced agnosticism, while not as bad as shafting just one company, still leads to peculiar running decisions in practice. Alas.
I did actually see what I thought were two different company's trains at plaform 8 in King's Cross (by left luggage, don't you know). One was GNER, "Route of the Flying Scotsman", but I don't remember what the other one was.
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