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Old December 5th, 2007, 09:34 AM   #1661
HAWC1506
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And skytrain is third rail, which should end this debate right here.
Are you saying my definition is acceptable?
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Old December 5th, 2007, 09:36 AM   #1662
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Quote:
Originally Posted by HAWC1506 View Post
Ah back to the distinction argument:

From what I have experienced and read:

Light Rail and Heavy Rail. Compare it to a metro bus and a long-rage greyhound bus.

Light Rail is generally used as an urban commuter, which generally travels at grade or above grade, with the ability and FLEXIBILITY to travel through streets. They typically do NOT have the ability to continually add train cars like heavy rail. They generally have a lower cost. The American Public Transportation Authority defines it as "An electric railway with a 'light volume' traffic capacity compared to heavy rail. Light rail may use shared or exclusive rights-of-way, high or low platform loading and multi-car trains or single cars." The electric railway part has a few exceptions because many light rail systems are powered by diesel. To me, it is a step lower than subway systems such as the ones in L.A.

Heavy Rail

With a few exceptions, most have higher capacities and they are able to increase the number of cars that each train can take. With a few exceptions, heavy rail trains are generally designed to go faster, but they are less flexible in terms of right of way. How did Japan and France figure out how to lay out their rail system? I don't know, but whatever they did, it's working very well. Heavy rail is built to serve areas with high density.

To sum it up, light rail has the flexibility in right of way, while heavy rail has the flexibility of capacity. Every rail system is designed differently with different needs and demands to be met, so the generalizations will not always apply. But the clearest distinction for me is their differences in flexibility.

Light Rail: Anywhere between 1 to approximately 6 train cars.
Heavy Rail: As much as the infrastructure can handle.
I've honestly never seen a 6 car light rail train before. Most I've seen is 4 cars max.
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Old December 5th, 2007, 06:18 PM   #1663
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Six cars would be insane. You get up to that need, and you should have just built a "heavy rail" system.
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Old December 5th, 2007, 08:22 PM   #1664
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Originally Posted by HAWC1506 View Post
Are you saying my definition is acceptable?
It's certainly more acceptable than trying to claim Skytrain is light rail.

There is NO distinction. There is NO authority saying "this is heavy, this is light". It's a matter of degree - a Skoda at-grade streetcar is light rail, and the NYC subway or the Shinkansen are heavy rail, but a whole set of properties change at different rates between those two ends.

You've got number of cars, width of cars, high floor or low floor, grade separation, third rail versus overhead, ticketed versus general seating, frequency of operation, etc etc etc... none of these things really "mean" light or heavy, we just make an arbitrary judgment about it.
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Old December 6th, 2007, 01:22 AM   #1665
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Six cars would be insane. You get up to that need, and you should have just built a "heavy rail" system.
Thanks for correcting, the Taipei rail system I was thinking of was not light rail, I got it confused with another system next to it.
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Old December 6th, 2007, 07:38 AM   #1666
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Quote:
Originally Posted by UrbanBen View Post
It's certainly more acceptable than trying to claim Skytrain is light rail.

There is NO distinction. There is NO authority saying "this is heavy, this is light". It's a matter of degree - a Skoda at-grade streetcar is light rail, and the NYC subway or the Shinkansen are heavy rail, but a whole set of properties change at different rates between those two ends.

You've got number of cars, width of cars, high floor or low floor, grade separation, third rail versus overhead, ticketed versus general seating, frequency of operation, etc etc etc... none of these things really "mean" light or heavy, we just make an arbitrary judgment about it.
I wholeheartedly agree. Trains. They're all trains.
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Old December 6th, 2007, 07:47 AM   #1667
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I wholeheartedly agree. Trains. They're all trains.
Hell yes, and we need more of them! The Sound Transit board has already directed Parsons Brinckerhoff (however you spell that) to work on ST2 planning. They'll go back to ballot, and those of us who live in Puget Sound need to help support it. There was no rail advocacy group last time around, but there's one starting now - a friend of mine has started to put one together.
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Old December 6th, 2007, 06:10 PM   #1668
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Hell yes, and we need more of them! The Sound Transit board has already directed Parsons Brinckerhoff (however you spell that) to work on ST2 planning. They'll go back to ballot, and those of us who live in Puget Sound need to help support it. There was no rail advocacy group last time around, but there's one starting now - a friend of mine has started to put one together.
When we see the vote results on this one, we'll know for sure what the problem was with prop 1. That is, if the voters vote yes on only a light rail measure, then we'll know that it was the roads portion that had a problem. If they vote no, then we'll know the voters just don't want new taxes.

I'm curious to know what impact the cross-base highway had on the vote.
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Old December 6th, 2007, 10:09 PM   #1669
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When we see the vote results on this one, we'll know for sure what the problem was with prop 1. That is, if the voters vote yes on only a light rail measure, then we'll know that it was the roads portion that had a problem. If they vote no, then we'll know the voters just don't want new taxes.

I'm curious to know what impact the cross-base highway had on the vote.
There is a huge survey that gives us a good idea. Overall, it was just too big and complex.
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Old December 6th, 2007, 11:06 PM   #1670
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A short, mildly technical treatsie on Vancouver's SkyTrain

Regarding the LINK. It's coming along great and I cannot wait to take a trip down to ride it!

Regarding the whole debate of whether x system is LRT and y system is a heavy metro, it is so much more complicated now than it was in the past and the limited vocabulary of distinctions seems to be hindering the dialogue.

Consider cars. These days you have micros, sub-compacts, compacts, mid-size, full size, coupes, station wagons, crossovers, compact SUVs, mid-size SUVs, full-size SUVs, and Hummers. Wait a year and there will be even more so they can all claim their offering is "best in its class".

I think the headway of a system and its passenger capacity should be the heart of the discourse. If a system is rail-based, frequent, has a good passenger capacity, and takes you where you want to go, who cares what you call it?

We call ours SkyTrain and it is a self-declared ALRT system, standing for Advanced Light Rapid Transit. It is a third rail, automated, intermediate-capacity transit system with a linear induction motor (LIM) propulsion system. The activator plate in the centre of the guideway represents half of the train's electric motor, with the other half being powerful electromagnets slung beneath the train. These magnets cycle from attract to repel in sequence to provide motive power in the same way a maglev train propels itself. The difference between two systems is that SkyTrain (the Vancouver name for Bombardier's ALRT system) relies on conventional steel rails and wheels in steerable boogies for conveyance instead of a maglev's magnetic levitation.

The whole point of the LIM technology is to maximize the life of the train by having a propulsion system that is solid state and free of moving parts. However the cost associated with engineering a LIM-based SkyTrain system massively outweighs the cost of overhauling electric motors and replacing the trains as they age. The above-mentioned two components of the LIM have precise tolerances and they must be kept within 5mm of one another to maintain steady motive power. To accomplish this the guideway and railbed require incredibly precise engineering and construction, far more so than a conventional LRT or conventional metro. A nice byproduct of this is that SkyTrain offers passengers a very smooth ride, largely free of the jerking and screeching around corners that is more common on older systems. General engineering and construction techniques have caught up with the demands of SkyTrain and building precise guideways is much easier today than it was in the early 80s when SkyTrain was first being built. The cost per kilometre is still quite high and we have only a single supplier for rolling stock, resulting in a king's ransom each time we need more trains.

Regarding capacity, the Skytrain system was designed in the early 80s to have a theoretical hourly passenger ceiling of 50,000 passengers, bidirectional. That figure was based on the use of a full complement of the initial trainset of Mk1 cars, the expansion of the existing 80-metre station platforms to their full 100-metre potential, and assumed the computers would be able to adhere to a best-possible operational headway of a little less than two minutes between trains. The moving block vehicle control software and the computers than run it have taken a quantum leap forward in the last twenty years and SkyTrain now routinely runs on less than 60 seconds of headway during the peak morning and evening periods. Combine this with the higher passenger capacities of the newer Mk2 trainset and I would suspect the current iteration of SkyTrain has a theoretical maximum hourly bidirectional passenger capacity well into the 75,000+ range. I do not know this for certain but is logical if the headways have been more than halved since the original 50,000 pax/hr/bidirection estimate. As it is we're packed in like sardines for four or five hours a day and comfortably full the rest of the time on the system that is currently running in the mid- to high-30,000 passengers per hour, bidirectional range. We have 34 more train cars on order with Bombardier and full delivery should occur in 2009. We need 'em!
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Old December 7th, 2007, 01:19 AM   #1671
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I think we can all agree on that 21st Century transportation is going to be by train. Governments should just spend their money rehabilitating highways and that's it; no widening (for the most part) and no additional capacity (if it's not necessary). We should just focus on rail, and fast.
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Old December 7th, 2007, 01:30 AM   #1672
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Quote:
Originally Posted by UrbanBen View Post
Hell yes, and we need more of them! The Sound Transit board has already directed Parsons Brinckerhoff (however you spell that) to work on ST2 planning. They'll go back to ballot, and those of us who live in Puget Sound need to help support it. There was no rail advocacy group last time around, but there's one starting now - a friend of mine has started to put one together.
Count me in! Is there information on what's going on with the plan?
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Old December 7th, 2007, 01:31 AM   #1673
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Quote:
Originally Posted by taiwanesedrummer36 View Post
I think we can all agree on that 21st Century transportation is going to be by train. Governments should just spend their money rehabilitating highways and that's it; no widening (for the most part) and no additional capacity (if it's not necessary). We should just focus on rail, and fast.
I was thinking Maglev. Would be cool if Seattle had a Maglev...
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Old December 7th, 2007, 02:03 AM   #1674
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I was thinking Maglev. Would be cool if Seattle had a Maglev...
It would set transportation planning in the region back a decade to try, because it would be seen as a boondoggle and undermine trust in our transportation agencies. Look at what the monorail (a feasible technology) project did to public perception of transit in Seattle.
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Old December 7th, 2007, 02:04 AM   #1675
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Quote:
Originally Posted by taiwanesedrummer36 View Post
I think we can all agree on that 21st Century transportation is going to be by train. Governments should just spend their money rehabilitating highways and that's it; no widening (for the most part) and no additional capacity (if it's not necessary). We should just focus on rail, and fast.
I wholeheartedly agree, BUT I'm willing to pay for some highway expansion to do it. 21st century transportation will be on train regardless of how many highways we have.
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Old December 7th, 2007, 02:09 AM   #1676
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Count me in! Is there information on what's going on with the plan?
It's likely that Sound Transit will do more engineering / alignment selection on East Link and then put the .4% package that they had before on the ballot.

It's not like the package needs to change. The problems are in subarea equity, not in where things will go.
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Old December 7th, 2007, 08:08 AM   #1677
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It would set transportation planning in the region back a decade to try, because it would be seen as a boondoggle and undermine trust in our transportation agencies. Look at what the monorail (a feasible technology) project did to public perception of transit in Seattle.
What do you mean?
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Old December 8th, 2007, 07:06 AM   #1678
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What do you mean?
I mean trying to build something with largely unproven technology where there are already a lot of hurdles is just one more thing that can go wrong. Your costs aren't as easy to estimate. Dude, just look at the monorail!
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Old December 8th, 2007, 08:35 AM   #1679
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I mean trying to build something with largely unproven technology where there are already a lot of hurdles is just one more thing that can go wrong. Your costs aren't as easy to estimate. Dude, just look at the monorail!
The monorail wasn't built as a true city commuter, was it?
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Old December 8th, 2007, 03:04 PM   #1680
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Quote:
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I mean trying to build something with largely unproven technology where there are already a lot of hurdles is just one more thing that can go wrong. Your costs aren't as easy to estimate. Dude, just look at the monorail!
Initial cost estimates for transit lines are notoriously bad even for proven technologies. Just look at the Central Link light rail line:

Central Link Light Rail
- Original Budget and Schedule
$1.7 billion for a 21-mile (some sources say 25-mile) line to open by
2006
- Actual Cost and Schedule
$2.44 billion for a 13.9-mile line from downtown to somewhere north
of the airport to open in 2009
+ $225 million (not including $75 million for roadway changes) for a
1.7-mile airport extension to open in 2009
+ $1.7 billion for a 3.15-mile extension to the university to open
perhaps in 2017

The present projection is that Central Link will be completed at a cost that is about 156% over the original budget and the line will reach the University District about a decade behind schedule. The estimates for the Green Line monorail were actually a lot closer:

Green Line Monorail
- Original Budget and Schedule
$1.75 billion for a 14-mile line to open between 2007 and 2009
- Total Cost and Schedule based on Pending Contract with Cascadia Monorail
$2.016 billion for a 14-mile line to open in 2009

The project was only about 15% over budget and was arguably on schedule. The situation on the finance side was worse due to a 30% shortfall in revenue from the Motor Vehicle Excise Tax (MVET) that was to fund the project.
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