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Post by Justin Walker on Oct 5, 2010 19:08:54 GMT -8
The only thing I would change is Green line extension goes up Lincoln instead of Sepulveda and terminates at Downtown Santa Monica with Expo. The 405 Corridor line should be a heavy rail line following Sepulveda (with slight detour to Westwood Village for transfer with Purple line) to LAX where it will join the Harbor Subdivision. Given that LRT can be built with just as much capacity as HRT (much like the Green Line), I maintain we should avoid deliberately building incompatible rail lines. The entire rail network will be more convenient if the rail line from the SFV is built as LRT and seamlessly continues on past LAX to either Norwalk or the South Bay.
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Post by bzcat on Oct 5, 2010 19:16:43 GMT -8
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Post by trackman on Oct 5, 2010 21:04:10 GMT -8
The only thing I would change is Green line extension goes up Lincoln instead of Sepulveda and terminates at Downtown Santa Monica with Expo. The 405 Corridor line should be a heavy rail line following Sepulveda (with slight detour to Westwood Village for transfer with Purple line) to LAX where it will join the Harbor Subdivision. Given that LRT can be built with just as much capacity as HRT (much like the Green Line), I maintain we should avoid deliberately building incompatible rail lines. The entire rail network will be more convenient if the rail line from the SFV is built as LRT and seamlessly continues on past LAX to either Norwalk or the South Bay. Technically speaking, this is not accurate. Metro's heavy rail system is faster, can have longer trains, and operate more closely with other trains versus light-rail systems. Heavy rail is also more prompt than LRT in many cases because grade separated lines do not need to compete with autos for space or time. All said, heavy rail has x2 to x3 the capacity as LRT. However, with heavy rail for Sepulveda, where is the maintenance yard? That will be a big question to answer. With light-rail, at least there's the flexibility to possibly expand an existing yard??? And, judging by aerial photogs of yards, LRT ones appear more compact and flexiblle. Regarding Sepulveda or Lincoln, I remain supportive of Lincoln first b/c it provides regional connectivity too. My map includes areas to the South and East.
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Post by jeisenbe on Oct 5, 2010 23:01:36 GMT -8
Technically speaking, this is not accurate. Metro's heavy rail system is faster, can have longer trains, and operate more closely with other trains versus light-rail systems. Heavy rail is also more prompt than LRT in many cases because grade separated lines do not need to compete with autos for space or time. All said, heavy rail has x2 to x3 the capacity as LRT. Not true. 1) Capacity: Light rail trains can be 6 double-cars long (Ottawa is building that now); our current "heavy rail" subway is limited to 6 car trains. 2) Frequency: light rail is operated with headways as low as 1 minute between trains in other parts of the world. Certainly it can achieve 2 minute headways, as good as most subways. 3) Speed: our current subway trains have a faster top speed of 70 mph, versus 65 mph for the green line, but acceleration is the same. There are faster light rail vehicles available, I believe, if we want to buy some. 4) Grade separation: the subway, with 3rd rail operation, needs grade separation, but light rail can be fully grade-separated too; see the Green Line for our local example. The Green Line could be fully automated, if it was cost-effective. The 405 line might interlace with the existing green line, and could be fully grade-separated, if it's worth it. Personally, I don't think it is worth the extra cost to keep it grade separated thru the SFV north of the Orange Line, but it can be done. So what's the real difference? Well, our light rail trains are a little narrower, have tighter turning radius, slightly lower height from rail to platform, and have overhead wires for power instead of a 3rd rail. That's about it. Our existing light rail trains also are only 3 cars long, and go 65 mph max, but that's based on current needs.
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Post by tobias087 on Oct 6, 2010 0:36:07 GMT -8
However, with heavy rail for Sepulveda, where is the maintenance yard? That will be a big question to answer. With light-rail, at least there's the flexibility to possibly expand an existing yard??? And, judging by aerial photogs of yards, LRT ones appear more compact and flexiblle. Regarding Sepulveda or Lincoln, I remain supportive of Lincoln first b/c it provides regional connectivity too. My map includes areas to the South and East. I must say, that thought had never occurred to me. If the 405 project is decided as LRT, which hopefully it will be without a fight, then where on earth will the maintainance facility be? Does anybody have any thoughts on this? Also, regarding Sepulveda vs. Lincoln, maps I've seen favoring Lincoln tend to either completely miss the SFV, by terminating in Santa Monica, or swing out in a clunky and contrived way to try and pick up the valley, like making a 90 degree turn to paralell the Expo line (or share tracks with it) then another 90 degree to up Westwood or Sepulveda. The Sepulveda route has the SFV included fairly naturally. That's really the tie-breaker for me. It just doesn't seem to me that Santa Monica is going to need the same headways as Downtown Los Angeles will through the Regional Connector (which is what you would get if the 2 lines shared tracks).
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Post by trackman on Oct 6, 2010 5:17:06 GMT -8
Technically speaking, this is not accurate. Metro's heavy rail system is faster, can have longer trains, and operate more closely with other trains versus light-rail systems. Heavy rail is also more prompt than LRT in many cases because grade separated lines do not need to compete with autos for space or time. All said, heavy rail has x2 to x3 the capacity as LRT. Not true. 1) Capacity: Light rail trains can be 6 double-cars long (Ottawa is building that now); our current "heavy rail" subway is limited to 6 car trains. 2) Frequency: light rail is operated with headways as low as 1 minute between trains in other parts of the world. Certainly it can achieve 2 minute headways, as good as most subways. 3) Speed: our current subway trains have a faster top speed of 70 mph, versus 65 mph for the green line, but acceleration is the same. There are faster light rail vehicles available, I believe, if we want to buy some. 4) Grade separation: the subway, with 3rd rail operation, needs grade separation, but light rail can be fully grade-separated too; see the Green Line for our local example. The Green Line could be fully automated, if it was cost-effective. The 405 line might interlace with the existing green line, and could be fully grade-separated, if it's worth it. Personally, I don't think it is worth the extra cost to keep it grade separated thru the SFV north of the Orange Line, but it can be done. So what's the real difference? Well, our light rail trains are a little narrower, have tighter turning radius, slightly lower height from rail to platform, and have overhead wires for power instead of a 3rd rail. That's about it. Our existing light rail trains also are only 3 cars long, and go 65 mph max, but that's based on current needs. Metro has built stations for trains no greater in length than for 3 cars. Heavy rail stations are built for 6 cars. Each car type has the same capacity. Therefore Metro's heavy rail system has x2 the capacity right there. As an aside, the ideal length for LRT is either 2 or 3 cars. Longer trains will be more troublesome when addressing door or coupler problems. And, can you imagine a 6-car LRT train at 540 feet long? Wow! And yes, heavy rail can operate faster. LRT - b/9 of middle/3rd set of axles affect the performance of cars. Granted, it is small. I stand by my other comments concerning the differences btwn light and heavy cars.
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Post by metrocenter on Oct 6, 2010 5:44:32 GMT -8
I've got to go with tobias087 and others on this argument: LRT along Sepulveda, from LAX to the Valley, seems to make the most sense.
Also, any such line would have to stop at UCLA.
Ultimately this line would be connected to the light rail network, and therefore could use any of the existing maintenance/storage facilities. But if they were to build the Valley-Westwood link first, I guess they'd have to build a small yard at the northern end of the line.
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K 22
Full Member
Posts: 117
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Post by K 22 on Oct 6, 2010 6:58:13 GMT -8
4) Grade separation: the subway, with 3rd rail operation, needs grade separation, but light rail can be fully grade-separated too; see the Green Line for our local example. The Green Line could be fully automated, if it was cost-effective. The 405 line might interlace with the existing green line, and could be fully grade-separated, if it's worth it. Personally, I don't think it is worth the extra cost to keep it grade separated thru the SFV north of the Orange Line, but it can be done. Wasn't an at-grade LRT on Van Nuys Blvd. on the table or at least talked about at some point in the past? I remember reading about that somewhere. Also I think this section of the valley would be more open to an LRT since (correct me if I'm wrong) it was more the people living on or near Chandler that prevented the Orange Line from being an LRT.
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Post by metrocenter on Oct 6, 2010 7:32:23 GMT -8
^^ Maybe 20 years ago, before Alan Robbins banned construction of light rail in the central Valley.
EDIT: The Robbins law (PUC 130265) only applies to trains crossing Tujunga Wash, so it would not apply to Van Nuys Blvd.
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Post by LAofAnaheim on Oct 6, 2010 7:59:00 GMT -8
So what's the real difference? Well, our light rail trains are a little narrower, have tighter turning radius, slightly lower height from rail to platform, and have overhead wires for power instead of a 3rd rail. That's about it. Our existing light rail trains also are only 3 cars long, and go 65 mph max, but that's based on current needs. Whenever I hear "tight turning radius" I shutter. The "tight turning curve" on top of the 101 freeway for the Gold Line is a disaster at 15 mph. It looks so painfully slow..and it is painfully slow. The curve at Washington/Flower on the Blue Line and the curve at 1st/Indiana is horrible as well. We don't experience this slowness out of Wilshire/Vermont; which I believe is the tightest curve for our subway system. If that's the case, it's another point in favor building a subway in the SFV.
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Post by metrocenter on Oct 6, 2010 8:14:31 GMT -8
So what's the real difference? Well, our light rail trains are a little narrower, have tighter turning radius, slightly lower height from rail to platform, and have overhead wires for power instead of a 3rd rail. That's about it. Our existing light rail trains also are only 3 cars long, and go 65 mph max, but that's based on current needs. Whenever I hear "tight turning radius" I shutter. The "tight turning curve" on top of the 101 freeway for the Gold Line is a disaster at 15 mph. He's just saying LRT is capable of tighter radii than HRT. The Sepulveda Pass Line would probably not be doing hairpin turns between the SF Valley and Westwood.
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Post by jdrcrasher on Oct 6, 2010 21:32:51 GMT -8
Unfortunately HRT has been all but ruled out for the Harbor Subdivision. That said, it would've been amazing. Not only would it have encouraged the 405 to be HRT (resulting in an even faster SFV-LAX-Long Beach commute than LRT), but it would also have brought to the table of connecting to the Red/Purple Line at Union Station. Plus, since this will supposedly connect with the Santa Ana Corridor, that project, too, would possibly have been HRT, which would have been useful given that particular line's length.
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