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aamslfc
Chief Train Controller
Joined: Mar 26, 2007
Last Visited: Dec 2, 2008
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Posted: Sat Oct 11, 2008 10:14 am
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Why is it 50 both ways over straight track at Ashfield anyway?
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simonl
Assistant Commissioner
Joined: Jan 05, 2006
Last Visited: Nov 16, 2008
Location: Brisbane
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Posted: Sat Oct 11, 2008 10:43 am
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| nadnerb_2000 wrote: | Mate - Strathfield and Central are 12km apart.
For a train to do that, requires an average speed of 60km/h. Thats not easy to do, even if you're not stopping at Redfern.
<snip> |
For the reasons you detail, yes. But what if it was a 115km/h board from Redfern to Granville? You should be able to average at least 80-90km/h depending on if your train is capable of over 100km/h or not. Sure, that's only 3-4 mins between Strathfield and Central, but extend to Granville, and that's another few mins.
| Quote: | | Frankly I think the running time between Central and Strathfield is very good. Leaves the alternative - Parramatta Road (with or without the City West Link) - for dead. The all stoppers, at around 19 minutes, aren't as good but those are in the minority and even that is a respectable time in peak hour. |
I wouldn't get that excited, but I do agree that Rail is a kick-smeg option for getting between the city and Stratfield/Burwood/Lidcombe/Granville/Parramatta/Blacktown/Penrith in peak hour.
I'd offer this counter example though:
I used to live in Harris Park and work near the west end of the Anzac Bridge. To drive, it usually took 35 mins in peak hour, although I did have two things in my favour: Jumping the toll plaza queue by getting on the M4 at James Ruse Dr, and getting off the City West Link shortly before the Anzac Bridge; but this was before the City West Link was finished. When I started working in the city, it usually took me 50 mins to catch the train door-door, and I lived 5 mins walk from the station. There's no way that the city is 3/7ths further from Harris Park than the Anzac Bridge, but it took that much longer.
Of course, this is largely due to waiting and walking times, but even the time on the train is only slightly faster than when I was driving in the peak.
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FieldShunt74
Chief Commissioner
Joined: Nov 06, 2004
Last Visited: Dec 2, 2008
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Posted: Sat Oct 11, 2008 4:48 pm
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| aamslfc wrote: | | Why is it 50 both ways over straight track at Ashfield anyway? |
Points and crossovers.
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simonl
Assistant Commissioner
Joined: Jan 05, 2006
Last Visited: Nov 16, 2008
Location: Brisbane
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Posted: Sat Oct 11, 2008 5:28 pm
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| FieldShunt74 wrote: | | aamslfc wrote: | | Why is it 50 both ways over straight track at Ashfield anyway? |
Points and crossovers. |
Are these points obsolete designs or something? All over the world trains do faster than 100km/h on the straight path through points and also (I believe) crossovers.
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aamslfc
Chief Train Controller
Joined: Mar 26, 2007
Last Visited: Dec 2, 2008
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Posted: Sat Oct 11, 2008 5:32 pm
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| FieldShunt74 wrote: | | aamslfc wrote: | | Why is it 50 both ways over straight track at Ashfield anyway? |
Points and crossovers. |
I know, but I'm sure there are other places of straight track on the network with similar points and crossovers that have higher speeds.
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GreaterNorthern
Station Master
Joined: Sep 16, 2007
Last Visited: Nov 14, 2008
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Posted: Sat Oct 11, 2008 7:33 pm
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Because you don't want this to happen again.
Photo: Stephen Halgren
In 1982 two trains on the Down Suburban & Up Local Lines collided after one derailed, presumably going too quickly at those crossovers.
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nadnerb_2000
Chief Commissioner
Joined: May 07, 2004
Last Visited: Nov 20, 2008
Location: between my hat and my shoe soles
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Posted: Sat Oct 11, 2008 9:44 pm
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| simonl wrote: | | nadnerb_2000 wrote: | Mate - Strathfield and Central are 12km apart.
For a train to do that, requires an average speed of 60km/h. Thats not easy to do, even if you're not stopping at Redfern.
<snip> |
For the reasons you detail, yes. But what if it was a 115km/h board from Redfern to Granville? |
Ah - the old "what if" question. What if I sold my car and bought a helicopter? I could save a lot of time then.
You'd need to do a lot of engineering to get the track up to 115 - you'd need to rebuild the entire line. No joke - it would need an entirely new alignment. Trains would also be further apart so you'd be sacrificing frequency for speed. And as the city has sortof grown up - you'd need either the mother of all tunnels, or to bulldoze a heck of a lot of homes after buying them out for $800,000 a pop. Its not an economical way to save time. Oh - and you think people would put up with bustitution, road closures, home reposessions, billions of taxpayer dollars spent on saving a train 3 minutes?
You'll find in most cities, trains get slower as they get closer to town. In a built up area the line usually has to twist around already established infrastructure. There are also noise issues and other such concerns keeping a lid on speed.
Want to compare notes with cities around the world? Have a look at Brisbane, things slow to a crawl in the city on the trains. Chicago - The EL train is decidedly slow, following the streets. New York - they achieve fast travel times with frequent services more than anything else.
Even the JR East Bullet trains out of Tokyo does not exceed 110km/h until they pass Omiya (IIRC), over 30 kilometres away - mainly due to track curvature. A built for the purpose high speed line - on a massive concrete viaduct or in tunnel the whole way - with a low speed limit. Thats not mentioning the TGV and Eurostar and all the European VHST trains which only spend about 30% of their time over 100km/h. Oh - and regular Japanese trains spend most of their time under 80km/h and making a heck of a lot of stops.
| simonl wrote: |
| Quote: |
Frankly I think the running time between Central and Strathfeld is very good. Leaves the alternative - Parramatta Road (with or without the City West Link) - for dead. The all stoppers, at around 19 minutes, aren't as good but those are in the minority and even that is a respectable time in peak hour. |
I wouldn't get that excited, but I do agree that Rail is a kick-smeg option for getting between the city and Stratfield/Burwood/Lidcombe/Granville/Parramatta/Blacktown/Penrith in peak hour.
I'd offer this counter example though:
I used to live in Harris Park and work near the west end of the Anzac Bridge. To drive, it usually took 35 mins in peak hour, although I did have two things in my favour: Jumping the toll plaza queue by getting on the M4 at James Ruse Dr, and getting off the City West Link shortly before the Anzac Bridge; but this was before the City West Link was finished. When I started working in the city, it usually took me 50 mins to catch the train door-door, and I lived 5 mins walk from the station. There's no way that the city is 3/7ths further from Harris Park than the Anzac Bridge, but it took that much longer. |
the City West Link is complete. So your argument is already out of date. But regardless:
Trains/public transport are slower than cars over most routes. Top Gear have even raced cars against the Eurostar, TGV and Bullet train - and won every time. Admittedly they picked the routes carefully and deliberately (and the car won by only 3 minutes in Japan even though it had a 240km shorter route), but it's legitimate - people pick the most direct route from A to B and public transport by definition can't always take the most direct route. It goes to show that no matter how fast you make a train, to many a car is more convenient, especially when you're not making a "conventional" trip. Try going from Carlingford to Epping by train and then by car - do you think you'd choose the train if it did it 5 minutes faster than the present time? Or even if the thing went non stop direct from Carlingford to Epping?
They can't build a direct railway track from everyone's house, to everyone's work. And if they did, there's no way you'd hit 115.
| Quote: | | Of course, this is largely due to waiting and walking times, but even the time on the train is only slightly faster than when I was driving in the peak. |
So - wouldn't it make more sense to reduce the waiting time? If you can cut a 15 minute wait down to 5 minutes, thats a better saving than 3 minutes you'd save with a major track reconstruction. Thats why metros and such work so well - its not the speed that counts, its the frequency. Though as people keep telling me, there arent really the paths available to achieve this on the current sydney system (though I think with in cab signalling and more standardised stopping patterns it could be done a little better).
| simonl wrote: |
Are these points obsolete designs or something? All over the world trains do faster than 100km/h on the straight path through points and also (I believe) crossovers. |
There are plenty of places on the CityRail network where trains can go full speed over crossovers in the "normal" position. Even plenty of places where they can go at 80-100km/h when the points are in the reversed position (eg: rhodes, beverly hills, glenfield - and concord west . . .  ).
But the points at Ashfield are slightly older, and are not high speed points. High speed points won't fit there. Compounding issues, that track is very heavily used and so the K rails cop a lot of wear and tear. Slower trains means less maintainence. Upgrading the points would require a very major shutdown, be expensive and take time.
You'd have to talk to an engineer though - trains on the down main do 100 through those points. And the crossovers near Summer Hill don't have the 50 speed restriction on them. So I don't know the specific reason why the 50 is on those ashfield crossovers.
I imagine one day they will probably upgrade them - hopefully replacing them with some more modern ones that will allow trains on the suburban to reach 80.
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FieldShunt74
Chief Commissioner
Joined: Nov 06, 2004
Last Visited: Dec 2, 2008
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Posted: Sat Oct 11, 2008 10:06 pm
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| simonl wrote: | | FieldShunt74 wrote: | | aamslfc wrote: | | Why is it 50 both ways over straight track at Ashfield anyway? |
Points and crossovers. |
Are these points obsolete designs or something? All over the world trains do faster than 100km/h on the straight path through points and also (I believe) crossovers. |
I figure that the engineers who are responsible for these particular points and crossovers are of at least average intelligence. I reckon they've probably seen a set of points or two in their time. They've got plenty of other points nearby with higher speeds, so they probably know what's possible.
If we take it that these guys aren't dolts, to whom the idea of a faster set of points just never occurred, I see a couple of other options. Perhaps the particular constraints on space, what with bridges, platforms and such, only lend themselves to a layout capable of 50 km/h? Perhaps the track could be rated for a higher speed but this would cause undue wear on the crossovers, considering their geometry, and 50 km/h is considered a better compromise between safety, line speed, and crossover life?
In any case, I'm not one of those engineers and don't know their reasoning here. But I expect they've put more thought into it than you or I, and know what's what. If it was safe/practical/economical to go faster, the speed limit would be higher, wouldn't it?
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aamslfc
Chief Train Controller
Joined: Mar 26, 2007
Last Visited: Dec 2, 2008
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Davy
Deputy Commissioner
Joined: Feb 11, 2004
Last Visited: Nov 21, 2008
Location: Old Main South
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Posted: Sat Oct 11, 2008 11:32 pm
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Anyone know why it is 35 down near Petersham?
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FieldShunt74
Chief Commissioner
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Posted: Sun Oct 12, 2008 12:09 am
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| Davy wrote: | | Anyone know why it is 35 down near Petersham? |
That one stretches my "they know what they're doing" hypothesis to the limit. 
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Bwana
Chief Commissioner
Joined: Jul 21, 2003
Last Visited: Dec 3, 2008
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Posted: Sun Oct 12, 2008 5:51 am
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| Davy wrote: | | Anyone know why it is 35 down near Petersham? |
If you read the entire thread you'd know by now...
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Jahommed
Locomotive Fireman
Joined: Aug 02, 2008
Last Visited: Nov 29, 2008
Location: G set toilet
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Posted: Sun Oct 12, 2008 6:24 am
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I personally think that if all trains stopped at all stations, then the network would be less congested. I mean sure travel times would be increased - by a lot - but the trains would remain a good distance behind the previous one.
The other day I was on a limited stops suburban to Bondi Junction. Little did i know that a late running all stopper had left 5minutes before. After stopping at Rockdale it was be a crawl till the entry to the ESR and then a 7minute wait until we were allowed to proceed. If all trains had the same stopping pattern we would almost completely eliminate this.
Im sure a lot would be unhappy if this happened but wouldn't it help? We could effectively increase frequency on the network because, as I said before, we would have less congestion.
Thanks, Jahommed
Tangara G sets are the best trains on the cityrail network.
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minifhncc
Junior Train Controller
Joined: Jan 22, 2008
Last Visited: Dec 2, 2008
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Posted: Sun Oct 12, 2008 2:27 pm
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I don't know about you, but I don't want to go from say, Lidcombe to Central on an all stops on the Inner West Line.
I know there are alternatives like the Western and South Lines, but sometimes when they're delayed or if I've just missed them, then the express Strathfield-Ashfield-Redfern-Central becomes handy.
I don't think modifying services is the thing to do. I think that more tracks need to be layed. Will it ever happen? Probably not.
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Jahommed
Locomotive Fireman
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Posted: Sun Oct 12, 2008 3:02 pm
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| minifhncc wrote: | I don't know about you, but I don't want to go from say, Lidcombe to Central on an all stops on the Inner West Line.
I know there are alternatives like the Western and South Lines, but sometimes when they're delayed or if I've just missed them, then the express Strathfield-Ashfield-Redfern-Central becomes handy.
I don't think modifying services is the thing to do. I think that more tracks need to be layed. Will it ever happen? Probably not. |
Yes well im sure you would rather go from Central to Lidcombe on an all stopper than on a limited stops train that is trailing behind an all stopper. Every single time you got close to building a considerable amount of speed you would have to slow down and wait a few minutes.
Also laying tracks would not only cost a fortune, it would take up valuable space. Where, on the North Shore Line can one or even more tracks be added. Very close to no where. Also, it would mean more money spent in the long run just repairing them.
Most lines only need a slight timetable change to drastically improve on time running and efficiency. For example make two limited stops depart 3 minutes apart, then 2 minutes or so afterwards send an all stopper. Give it about 6 minutes and then repeat the process. Or send a limited stops train and then an all stopper 1 minute afterwards. The all stopper can travel slowly for the first couple of stations (as they always do) while the train ahead gets a good lead. You see my point.
Thanks, Jahommed
Tangara G sets are the best trains on the cityrail network.
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