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Timer Leaving 34 St Penn ACE Downtown Local


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Has anyone noticed a timer on downtown local by 34 St Penn Station (ACE) line?

Now when a downtown local train starts to leave slowly first then it speeds up. I've noticed that for quite some time and I've seen the actual signal and the light changed when I was on (A) Exp and we went ahead of the local train as it slowed down first. Plus i remember before when downtown trains use to leave out fast at 34 St Penn Station.

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Hey Medic, while we are on the topic of timers, have they put any new ones on the QBL express tracks? I know they resignalled Roosevelt Ave and seems like the trains have run slower the past few months than they used to.

It certainly seems that way..... CBTC can't get here any faster. Safety department is destroying the meaning of "rapid transit" with all these timers.

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I hate timers.

 

On CPW it could take 4 minutes to get from 125th down to 59th, but with all these timers it takes 12 minutes.

 

QBL is just down right horrific...the headway on that route are so messed up chances are you'll get 6 (M)'s before a (F) comes.

 

The only place that still hasn't been damaged badly by timers in on Flushing Express from 33rd to Willets.

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I hate timers.

 

On CPW it could take 4 minutes to get from 125th down to 59th, but with all these timers it takes 12 minutes.

 

QBL is just down right horrific...the headway on that route are so messed up chances are you'll get 6 (M)'s before a (F) comes.

 

The only place that still hasn't been damaged badly by timers in on Flushing Express from 33rd to Willets.

Now you're exaggerating. It doesn't take 12 minutes on the express, there's only 2 known timers on that stretch and they been there for ages.
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Now you're exaggerating. It doesn't take 12 minutes on the express, there's only 2 known timers on that stretch and they been there for ages.

 

Agree completely. Those timers have been there my entire life. From what my dad and grandfather have told me, those are some of the oldest in the system,

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Express from 59-125 or vice versa takes about 7-8 minutes. And yes, those timers have been there forever, although there are more of them than there used to be northbound.

 

CBTC only appears to reduce running times because the computer allows the train to run faster than it allows a human. CBTC also allows a single incident to cause catastrophic delays along the line, whereas conventional signalling does not.

 

"Rapid Transit" is possible with conventional signals and intelligent design of new routes, with proper signal spacing based on maximum attainable speeds, and the fewest curves, obstructions to work around, and junction to reduce or eliminate slower speed moves.

 

The timer at 34th was installed to reduce the maximum attainable speed of a train approaching 23rd St. for additional protection behind a train that has just left or is partway sitting in the station. This is due to the long spacing in signals between 39 ball and the following automatic. If there were additional signals in that area to provide an equivalent level of protection, the timer would not be necessary.

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Conventional signals with even spacing would be perfect, but it's like the MTA has made computers and electronic BS a prerequisite for everything, including that which doesn't need it.  And a lot of sheeple seem to fall for it, as if CBTC was the end-all/be-all or something...

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The antiquity of such a system can be seen in many cases. Today, going to Central Park, the Bronx-bound (B) train I was on pulled into 59 Street–Columbus Circle immediately after the (D) ahead of us did. The (D) was already gone by the time the (B) platformed, but the (A) train that I saw in the tunnel did not pull in until the (B) closed its doors and was pulling out. Ideally, the (A) should be moving in as the (D) is moving out, keeping a more-or-less constant distance between the two trains. If the (B) could pull in, physically, the (A) should have been able to without broaching the safe stopping distance.

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The antiquity of such a system can be seen in many cases. Today, going to Central Park, the Bronx-bound (B) train I was on pulled into 59 Street–Columbus Circle immediately after the (D) ahead of us did. The (D) was already gone by the time the (B) platformed, but the (A) train that I saw in the tunnel did not pull in until the (B) closed its doors and was pulling out. Ideally, the (A) should be moving in as the (D) is moving out, keeping a more-or-less constant distance between the two trains. If the (B) could pull in, physically, the (A) should have been able to without broaching the safe stopping distance.

 

Theoretically, they could do that with station time. Of course, we also have the issue of fixed blocks forcing 2 reds between trains unless station time or a train keys by.

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The antiquity of such a system can be seen in many cases. Today, going to Central Park, the Bronx-bound (B) train I was on pulled into 59 Street–Columbus Circle immediately after the (D) ahead of us did. The (D) was already gone by the time the (B) platformed, but the (A) train that I saw in the tunnel did not pull in until the (B) closed its doors and was pulling out. Ideally, the (A) should be moving in as the (D) is moving out, keeping a more-or-less constant distance between the two trains. If the (B) could pull in, physically, the (A) should have been able to without broaching the safe stopping distance.

 

When service headways are that frequent, such as during rush hour, connections don't matter. The goal is to keep trains moving, not hold them for connections.

 

With fixed block signals, at junctions, a train will be held to give its leader a safe distance, then can more or less proceed normally after that.

 

With CBTC, the trains will be allowed to close in on each other (similar to how station time works with conventional signals), but will still have to respect the safe distance, which is just more speed variable than under conventional signalling. Again, the issue is if a zone controller goes bad, every train in an entire area goes BIE under CBTC. If a single signal causes a BIE, service can continue with delays, and only the one train will have gone BIE. Likewise, if CBTC fails completely, the entire line can go BIE.

 

It's a risk reward calculation. THat's the problem with all the newfangled computer stuff. It's not designed to withstand a rigorous environment like NYC. It's "wonderful" under ideal conditions, but ideal conditions are rarely possible. Think of it this way - If you're the football coach of the Seattle Seahawks (think Seattle weather) would you rather have a running back that can run for 200 yards a game if it's sunny and dry, but will only run for 10 in rain, or would you rather have a running back that can run for 150 yards a game, but itsn't bothered by a wet field and can run for 100 still?

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In all seriousness - do any major signal suppliers still do brand new, off-the-shelf fixed-block systems? Signals have to be replaced anyways, and if no one is offering high-capacity fixed block anymore then it's not like you can install it. It would be like someone trying to buy a CRT TV today.

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In all seriousness - do any major signal suppliers still do brand new, off-the-shelf fixed-block systems? Signals have to be replaced anyways, and if no one is offering high-capacity fixed block anymore then it's not like you can install it. It would be like someone trying to buy a CRT TV today.

 

At this point, I doubt it. Not many systems even use pure fixed block anymore. In North America, New York, Toronto and Boston are the only ones with it. London has it and I think Berlin does as well, but that's just about it. Chicago updated to cab signals at some point and most systems (Washington, for example) are new enough to use moving block.

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