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Terminal & Line Segment Limitations Inquiry

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A recent post, referenced below, made an interesting inquiry in my opinion, just how many trains can run on a particular segment of a line or through a particular terminal.

We know that most lines can operate about 30 trains per hour, but limitations on certain segments and at a few terminals significantly reduce that number. We know that Jamaica Center is maxed out at 12. The Flatbush Av terminal and DeKalb Junction are similarly restricted. My question is, what other areas have these restrictions and if possible, what are the max number of trains that can comfortably run on these segments?

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In my experience, lines with tail tracks at just one terminal allows more TPH to be added, however most of the terminals we have are vastly underused, such as 179th St. 

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22 minutes ago, Lawrence St said:

In my experience, lines with tail tracks at just one terminal allows more TPH to be added, however most of the terminals we have are vastly underused, such as 179th St. 

Well, Jamaica–179 Street was designed to be both a terminal (for local trains) and a through station (for express trains).

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This obviously ain't my area of knowledge - aside from playing Jan Bochmann's Bahn in the past, but I'd like to know what actually limits capacity beyond the generic "signals and lack of tail tracks."

For example:

How does signaling limit it? Is it that the length of each block and the amount of time/distance that must be covered when a train enters the next block, along with the speed limit for that section, limit how many can go through? (I.E., if the block is 1000 feet long, or 1.25 train lengths, and the speed limit is 35, is that length too long and speed too low? Would shortening the block and increasing the speed allow another train through?

Or at junctions. Does merging or splitting two tracks restrict capacity because of minimum distance between trains, or is it the amount of time it takes for a switch to change positions? Is there an "integrity check" that has to be completed when the switch moves from one track to another before the block is cleared for travel? Or is it that the local dispatcher only has so much capacity to hit the button to move the switch as needed/necessary?

Or at terminals. is capacity limited by how long it takes for crews to staff the train and do the safety checks? Is there a way to speed that up? Are the PA checks and whatnot superfluous since the train's PA worked when it pulled in, and the train wasn't shut off when it's operating direction was reversed, so the system can reasonably assumed to still work? Or in the case of brake bleeding after terminating - since it's done by the outgoing crew, does the incoming crew truly need to bleed the system again before it's underway?

That's the train geek knowledge I'd be interested in in order to participate in this "effectively" and seriously, assuming I still had the time to do so.

 

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Alright, here are the ones I know+some educated guesses (B div only). I assume I’ve made some mistakes, so please please let me know! 

I’ll follow up later with my knowledge of merge limits, line cap limits, and the few A div terminals I know about. 

207 — 18 tph — entry speed and presence of bumper is the limiting.

Lefferts — 12 tph — same issue

Frock — 12 tph — ditto

RPK — 10ish tph — ditto, and switch config

BPB — 7.5 tph, but there’s loads of ways not to use the middle track to turn trains, so it’s really more. 

145 — 8 or 9 tph — single track with 15 mph switches. 

Brighton Beach — I don’t know for sure, but given that the terminal’s overall config is not unlike that of Fhills, I’d guesstimate 18 tph or thereabouts, with fumigation being the limiter. 

168 — 22ish tph — fumigation limiting. 

Euclid — 13-15tph. Relay availability seems to be limiting 

205 — 15. Relay and fumigation limiting. 

CI (all tracks) — 10-12 tph. The obtuse positioning of the switches and the presence of curves on the south end limiting. 

Jamaica Center (both) — 12tph. Length of control lines, signal blocks, and switch position. 

WTC — 15-16 tph. Bumpers. 

179 — infinite. (Okay, 24/track, with fumigation being the limiter) 

Kings Highway — 7.5, though that terminal is 90% used for fumigation of yard runs. 

Church — 10-12 tph, but even that much causes delays. 

Court Square — 15 tph — they use a relay track as a crossover. 

Broad St — 12-14 tph. Relay positions limiting. 

Chambers — 8tph. Relay limiting. 

8th Ave — 24tph. Bumpers, but has CBTC which makes it work better. Only can get 20 today because of power (or lack thereof). 

Myrtle Wyckoff—10ish tph. Need to not delay other trains, and time to turn in relay limiting. 

Rockaway Parkway — 20ish tph. Switch position and speed limiting. 

Metropolitan — 16 tph. Switch speed and the presence of a bumper. 

FH71 — 22tph. Fumigation (and 22 is really pushing it).

Ditmars — 16tph. Poor switch design and bumpers.

96 — 30tph. Line capacity limiting. 

95th — 13-14tph. Switch speed and bumpers limiting. 

Whitehall — 7tph. Slow switches and crazy curve north of the sta.

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2 hours ago, CenSin said:

Well, Jamaica–179 Street was designed to be both a terminal (for local trains) and a through station (for express trains).

Shame we never finished that extension tho.

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I can confirm that all northbound (B) trains stop at Myrtle Av to confirm their direction.

Edited by P3F

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1 hour ago, RR503 said:

Alright, here are the ones I know+some educated guesses (B div only). I assume I’ve made some mistakes, so please please let me know! 

I’ll follow up later with my knowledge of merge limits, line cap limits, and the few A div terminals I know about. 

207 — 18 tph — entry speed and presence of bumper is the limiting.

Lefferts — 12 tph — same issue

Frock — 12 tph — ditto

RPK — 10ish tph — ditto, and switch config

BPB — 7.5 tph, but there’s loads of ways not to use the middle track to turn trains, so it’s really more. 

145 — 8 or 9 tph — single track with 15 mph switches. 

Brighton Beach — I don’t know for sure, but given that the terminal’s overall config is not unlike that of Fhills, I’d guesstimate 18 tph or thereabouts, with fumigation being the limiter. 

168 — 22ish tph — fumigation limiting. 

Euclid — 13-15tph. Relay availability seems to be limiting 

205 — 15. Relay and fumigation limiting. 

CI (all tracks) — 10-12 tph. The obtuse positioning of the switches and the presence of curves on the south end limiting. 

Jamaica Center (both) — 12tph. Length of control lines, signal blocks, and switch position. 

WTC — 15-16 tph. Bumpers. 

179 — infinite. (Okay, 24/track, with fumigation being the limiter) 

Kings Highway — 7.5, though that terminal is 90% used for fumigation of yard runs. 

Church — 10-12 tph, but even that much causes delays. 

Court Square — 15 tph — they use a relay track as a crossover. 

Broad St — 12-14 tph. Relay positions limiting. 

Chambers — 8tph. Relay limiting. 

8th Ave — 24tph. Bumpers, but has CBTC which makes it work better. Only can get 20 today because of power (or lack thereof). 

Myrtle Wyckoff—10ish tph. Need to not delay other trains, and time to turn in relay limiting. 

Rockaway Parkway — 20ish tph. Switch position and speed limiting. 

Metropolitan — 16 tph. Switch speed and the presence of a bumper. 

FH71 — 22tph. Fumigation (and 22 is really pushing it).

Ditmars — 16tph. Poor switch design and bumpers.

96 — 30tph. Line capacity limiting. 

95th — 13-14tph. Switch speed and bumpers limiting. 

Whitehall — 7tph. Slow switches and crazy curve north of the sta.

Brighton Beach isn't a fumigation terminal. It's equivalent to a two track-two side platform terminal such as Flatbush Av. In addition, there is a slow curve north of the station. 18 TPH from that setup seems nowhere near realistic.

Also, please provide your opinions on Prospect Park, Franklin Av, St. George, Great Kills, and Tottenville. When thinking about St. George pay very close attention to the ability or lack thereof to access certain tunnel tracks from the different areas of the terminal.

Edited by P3F

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2 hours ago, P3F said:

I can confirm that all northbound (B) trains stop at Myrtle Av to confirm their direction.

As do s/b (N)(Q) I believe. 

1 hour ago, P3F said:

Brighton Beach isn't a fumigation terminal. It's equivalent to a two track-two side platform terminal such as Flatbush Av. In addition, there is a slow curve north of the station. 18 TPH from that setup seems nowhere near realistic.

Also, please provide your opinions on Prospect Park, Franklin Av, St. George, Great Kills, and Tottenville. When thinking about St. George pay very close attention to the ability or lack thereof to access certain tunnel tracks from the different areas of the terminal.

...doink! My never having fanned southern Brighton on a weekday comes back to bite me. Thanks for the correction. The 10 number now sounds more believable. 

Prospect and Franklin can both handle only 6-7 tph. The limiting factor there is the extended lengths of single track on the (S)

I know nothing about SIRT's ops policies and switch geometries, so I'll let some more knowledgeable person chime in for that. 

As for line capacity restrictions, the only place I can think of where something that is not a switch or terminal limits service to a number far below 30 is on the Williamsburg Bridge, where it's 25/direction. Of course, many of the timers across the system have a negative impact on throughput, but they're much harder to quantify. 

 

Now, merges. 

The ones that I know to be icky are the following: 

Rogers, which limits the EPW line to ~25 per track, and the Nostrand Ave. Line (working in concert with FABC) to 20tph. 

Dekalb, which limits all Manhattan Bridge services to about 18-20 tph/track. 

75th ave, which kills QB express reliability by making (E)s sit and wait for (F)s to navigate a 15 mph crossover

34th st-Broadway, which has (N)s navigate a 13 mph crossover, limiting service to 25ish tph/track (and that's if we forget about terminals). 

Hoyt-Schermerhorn/Canal, which reduces Fulton/Cranberry cap from 30 to 27.

Myrtle-Broadway, which limits the Jamaica/Myrtle lines to a combined 27ish tph. 

 

I think that it's important to remember when considering things like this that most of these issues are as much a function of MTA policy as they are of infrastructural realities.

If, for example, the agency had T/Os waiting to meet incoming trains at their terminals positioned at the 'new' front of the train, then we could forget about brake dumping/recharging, and the time it takes to walk down the entire train. Similarly, if we had staff at fumigation terminals positioned on the platform ready to empty out all trains, then we could alleviate some of those delays too. So those limits above while extant, are only so given current practices. They are by no means unchangeable. 

Same thing goes for merges. Yes, they limit capacity, but eliminating them (ie deinterlining) gives you those tph back. Before someone gets triggered, I'm not slyly advocating that we should across the board, just saying that it is indeed a valid way of adding capacity. 

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4 hours ago, RR503 said:

Hoyt-Schermerhorn/Canal, which reduces Fulton/Cranberry cap from 30 to 27.

 

4 hours ago, RR503 said:

Dekalb, which limits all Manhattan Bridge services to about 18-20 tph/track. 

Like this. This is what I’m asking for specifics on - what makes these two specific areas a bottleneck?

Is it that the signal blocks being 1000 ft, and trains being 600 ft, result in trackage being wasted? Is it that the switches take too long to switch back for trains on either track?

Because looking at Dekalb, it’s all flying junctions so unless all the trains arrive at the same time, the only things that seem to limit it - to me - are unnecessarily long signal blocks, switch track timing, and/or dispatcher’s capacity.

I don’t know the specifics of how the Chicago L operates, but I’ve been in the loop and have seen trains on both sides one station apart moving safely and negotiating the crossover junctions without trains stopped forever waiting for it to clear.

So what is it here in NYC that is specifically responsible for the capacity crunches and “train traffic delays?

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For Dekalb, it’s a profusion of timers without requisite block shortening, the need to stop mid-interlocking and wait for a line-up, and the impossibility of getting trains to meet their slots in this day and age. 

For Hoyt/Canal, it’s the speed over those switches. 

I too admire Chi-town. No idea how they do it. But it’s amazing. 

Edited by RR503

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48 minutes ago, Deucey said:

 

Like this. This is what I’m asking for specifics on - what makes these two specific areas a bottleneck?

Is it that the signal blocks being 1000 ft, and trains being 600 ft, result in trackage being wasted? Is it that the switches take too long to switch back for trains on either track?

Because looking at Dekalb, it’s all flying junctions so unless all the trains arrive at the same time, the only things that seem to limit it - to me - are unnecessarily long signal blocks, switch track timing, and/or dispatcher’s capacity.

I don’t know the specifics of how the Chicago L operates, but I’ve been in the loop and have seen trains on both sides one station apart moving safely and negotiating the crossover junctions without trains stopped forever waiting for it to clear.

So what is it here in NYC that is specifically responsible for the capacity crunches and “train traffic delays?

The issue is getting trains to show up at the junction at the right time. Keeping, say, the (B) and (D) all synced up without interference requires them to run the exact same amount of service because otherwise the math doesn't work; you can't run one service every 6 minutes and one every 8, or one every 4 and one every 8, without uneven headways and conflicts on either the outer ends or the central segments.

On top of that, throw reverse-branching into the mix. New York is pretty much unique in having a system where lots of branches combine together at their outer ends. Making all of it balance out is made even harder by the fact that the (N) , (Q) , and  (R) all mix together in the 60th St tube, which forces you to either gimp service on every single branch to run reliable service at the capacity imposed by that constraint, or run services that will inevitably conflict and try and hope for the best. And the (R) basically is indirectly connected to every single B-Division line except the (L) . So it's all a giant mess.

Edited by bobtehpanda
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1 hour ago, RR503 said:

For Dekalb, it’s a profusion of timers without requisite block shortening, the need to stop mid-interlocking and wait for a line-up, and the impossibility of getting trains to meet their slots in this day and age. 

For Hoyt/Canal, it’s the speed over those switches. 

I too admire Chi-town. No idea how they do it. But it’s amazing. 

It’s probably the MTA’s insistence on following the schedule or humans being bad at their jobs. I don’t know how automated the junctions are, but sometimes I feel that somebody at the controls is always tripping over their own tails trying to figure out which train should go first when the trains are waiting by the switches for like 3 minutes. This happens at 36 Street, 34 Street–Herald Square/42 Street–Times Square, 59 Street–Columbus Circle, Queens Plaza…

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If memory serves me correctly, New South Ferry, a terminal with no tail tracks, was quoted as 24TPH. I also remember that Flushing-Main St actually has less terminal capacity than that on account of the complicated switching patterns required by the three track terminal, which was supposed to function more like Parkchester if there was ever an extension east.

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8 hours ago, RR503 said:

 

 

 

I think that it's important to remember when considering things like this that most of these issues are as much a function of MTA policy as they are of infrastructural realities.

If, for example, the agency had T/Os waiting to meet incoming trains at their terminals positioned at the 'new' front of the train, then we could forget about brake dumping/recharging, and the time it takes to walk down the entire train. Similarly, if we had staff at fumigation terminals positioned on the platform ready to empty out all trains, then we could alleviate some of those delays too. So those limits above while extant, are only so given current practices. They are by no means unchangeable. 

Same thing goes for merges. Yes, they limit capacity, but eliminating them (ie deinterlining) gives you those tph back. Before someone gets triggered, I'm not slyly advocating that we should across the board, just saying that it is indeed a valid way of adding capacity. 

As far as T/Os meeting incoming trains at their terminals I'll give you my experiences

(1) 242nd St- VC or 137th St  done that

(2) 241st St or New Lots or Flatbush  done that

(3) Lenox Terminal or Flatbush or New Lots done that

(4) Woodlawn  done that ( Break in) or Atlantic Avenue that too

(5) Dyre Avenue, 241 St, Atlantic Avenue, Flatbush Avenue that too

(6) Pelham Bay Park, Parkchester that too

(7) Main St or Times Square yep

Although I never worked the (4) , (6) , or (7) on a regular basis every terminal I referenced above has used your idea about prepositioning in the past. As for your fumigation idea I'm sorry to tell you that that ship has sailed. If a train arrives at a terminal today and a rider refuses to leave the train it doesn't matter how many fumigators are available. Even NYPD tries to avoid that confrontation. Legal issues all around that scenario. Thirty five years ago if a train came into Lenox Terminal and had to be fumigated by me and the RCI we had carte blanche to use what ever method we wanted to remove those who dallied too long. Po Po taught me that a stomp to a sleeping/drunks instep was always guaranteed to get a reaction. The metal brake handle to the temple worked too. Nowadays that might be considered assault but it always worked for us. Even with 5-0 standing there to make sure things didn't get out of hand. We had our own ways back then, brutal but effective. Can't do that today so we play by the rules. Carry on.

 

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6 hours ago, Trainmaster5 said:

As far as T/Os meeting incoming trains at their terminals I'll give you my experiences

(1) 242nd St- VC or 137th St  done that

(2) 241st St or New Lots or Flatbush  done that

(3) Lenox Terminal or Flatbush or New Lots done that

(4) Woodlawn  done that ( Break in) or Atlantic Avenue that too

(5) Dyre Avenue, 241 St, Atlantic Avenue, Flatbush Avenue that too

(6) Pelham Bay Park, Parkchester that too

(7) Main St or Times Square yep

Although I never worked the (4) , (6) , or (7) on a regular basis every terminal I referenced above has used your idea about prepositioning in the past. As for your fumigation idea I'm sorry to tell you that that ship has sailed. If a train arrives at a terminal today and a rider refuses to leave the train it doesn't matter how many fumigators are available. Even NYPD tries to avoid that confrontation. Legal issues all around that scenario. Thirty five years ago if a train came into Lenox Terminal and had to be fumigated by me and the RCI we had carte blanche to use what ever method we wanted to remove those who dallied too long. Po Po taught me that a stomp to a sleeping/drunks instep was always guaranteed to get a reaction. The metal brake handle to the temple worked too. Nowadays that might be considered assault but it always worked for us. Even with 5-0 standing there to make sure things didn't get out of hand. We had our own ways back then, brutal but effective. Can't do that today so we play by the rules. Carry on.

For the meeting thing, I'm glad to hear that it's being done on the A div, but at terminals on the B div like Whitehall, 8th Ave, Jamaica Center, and WTC, it's not, and that could *really* help speed things along at those capacity-critical terminals. 

And for the fumigation thing. Yes, if a rider refuses to leave, you have an issue. But nine times out of ten, that won't happen -- they'll just leave -- and it's in those situations that it could be helpful.

Take those (5)s that turn at Bowling Green during the rush. Those trains sit at the platform for 4 or 5 minutes as the conductor walks through the train making sure everyone is off. During that time, trains stack up behind it, leading to messes in Brooklyn. Having people ready to assist in fumigation would quicken that process, and reduce those delays. 

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1 hour ago, RR503 said:

 

Take those (5)s that turn at Bowling Green during the rush. Those trains sit at the platform for 4 or 5 minutes as the conductor walks through the train making sure everyone is off. During that time, trains stack up behind it, leading to messes in Brooklyn. Having people ready to assist in fumigation would quicken that process, and reduce those delays. 

To be honest, I don't see a need to fumigate those Bowling Green short turns unless they are deadheading as those trains are just looping back around anyways. I know trains might sit there for up to an hour, but can't you just have it run as the next train north?

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Yesterday while on the Manhattan bound (R) coming from Forest Hills - 71 Av.  I saw a whole line of (R) and (M) trains backed up as far back as Woodhaven Blvd. I think I counted about 5 local trains backed up and the (E) and (F) was suffering from being backed up too on the express track. 

The process to clean and clear out all the trains at Forest Hills hurts service and I wonder why Jamaica 179 can’t be utilized more than what it currently is. My suspicions is that the additional local service (M) prevents and (R) and (F) from going 179 and the slow speed the (E) has when switching onto the express track at Briarwood from the Archer Ave track. Maybe the MTA should invest in constructing a proper terminal for the (R) and (M) in Queens to avoid the slow down which I know they probably won’t.  

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(M) to 179th with (F) express?

Wonder how that'd play out since it'd eliminate the (E)(F) merge after Continental.

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1 hour ago, NewFlyer 230 said:

Yesterday while on the Manhattan bound (R) coming from Forest Hills - 71 Av.  I saw a whole line of (R) and (M) trains backed up as far back as Woodhaven Blvd. I think I counted about 5 local trains backed up and the (E) and (F) was suffering from being backed up too on the express track. 

The process to clean and clear out all the trains at Forest Hills hurts service and I wonder why Jamaica 179 can’t be utilized more than what it currently is. My suspicions is that the additional local service (M) prevents and (R) and (F) from going 179 and the slow speed the (E) has when switching onto the express track at Briarwood from the Archer Ave track. Maybe the MTA should invest in constructing a proper terminal for the (R) and (M) in Queens to avoid the slow down which I know they probably won’t.  

If they’re going to bend over backwards to keep Queens Boulevard express service serving the local stations east of Forest Hills, they might as well give the Queens bypass a head start and build a lower level below Forest Hills that can be used to terminate local trains too.

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I don’t see how a 179 extension would help. Sure, you can enter the relays slightly faster, but aside from that, you still have to fumigate — which is the big delay causer at 71. I think a better course of action would be to have 5 or 6 platform conductors waiting to clear out the train at the station — then the train crew wouldn’t have to leave their cabs, and the whole process would move a lot faster. 

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26 minutes ago, RR503 said:

I don’t see how a 179 extension would help. Sure, you can enter the relays slightly faster, but aside from that, you still have to fumigate — which is the big delay causer at 71. I think a better course of action would be to have 5 or 6 platform conductors waiting to clear out the train at the station — then the train crew wouldn’t have to leave their cabs, and the whole process would move a lot faster. 

By the time the train reaches 179, it should be much emptier than when it would be at Forest Hills. Plus, you can utilize both tracks (express and local) to terminate trains. I would agree with stationing platform conductors to clear the train, something that should be done at stations like Bowling Green for the (5) .

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14 minutes ago, R68OnBroadway said:

By the time the train reaches 179, it should be much emptier than when it would be at Forest Hills. Plus, you can utilize both tracks (express and local) to terminate trains. I would agree with stationing platform conductors to clear the train, something that should be done at stations like Bowling Green for the (5) .

Nope. No one takes the local from Manhattan/LIC/anywhere west of Roosevelt to FHills. Similarly, no one will take the local from anywhere beyond Kew Gardens to 179. Put differently, I’ve never seen a local arrive at Fhills with more than a few people inside. 

As for the availability of tracks at 179, I agree that helps. But, if you extend both services to 179 (which you’d need to do lest you end up with a much-worse Church Ave.), you end up with something on the order of 36tph (15 (F), 11 (M), 10 (R)) terminating at 179. Spread across two tracks, that’s 18 tph/track — or nearly what FHills does today. What’s more, if you have trains taking the “incorrect” inbound track at 179, there’s no way they can switch to the “correct” track when reentering, leading to confusion about where one’s train will arrive. And of course, this is to say nothing of the delays that come with willy-nilly merging at 169. 

So yes, a 179 extension would be nice as the (F) could lose some stops, and stop having to make that awful merge at 75, but I think to claim that the terminal situation would be any better than that of 71 is misleading. 

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2 hours ago, RR503 said:

Nope. No one takes the local from Manhattan/LIC/anywhere west of Roosevelt to FHills. Similarly, no one will take the local from anywhere beyond Kew Gardens to 179. Put differently, I’ve never seen a local arrive at Fhills with more than a few people inside. 

As for the availability of tracks at 179, I agree that helps. But, if you extend both services to 179 (which you’d need to do lest you end up with a much-worse Church Ave.), you end up with something on the order of 36tph (15 (F), 11 (M), 10 (R)) terminating at 179. Spread across two tracks, that’s 18 tph/track — or nearly what FHills does today. What’s more, if you have trains taking the “incorrect” inbound track at 179, there’s no way they can switch to the “correct” track when reentering, leading to confusion about where one’s train will arrive. And of course, this is to say nothing of the delays that come with willy-nilly merging at 169. 

So yes, a 179 extension would be nice as the (F) could lose some stops, and stop having to make that awful merge at 75, but I think to claim that the terminal situation would be any better than that of 71 is misleading. 

How much room is left at Jamaica Center? Probably none, but if you could move the (M) there if you  somehow increase capacity there. If you did that, then you could have the (F) on the express and (R) on the local in terms of termination, but other than that, a extension to 179 will only solve the 75th merge isssue and not the fumigation and backup issues.

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3 hours ago, R68OnBroadway said:

How much room is left at Jamaica Center? Probably none, but if you could move the (M) there if you  somehow increase capacity there. If you did that, then you could have the (F) on the express and (R) on the local in terms of termination, but other than that, a extension to 179 will only solve the 75th merge isssue and not the fumigation and backup issues.

Jamaica Center has -3 trains per hour to spare in capacity. Remember that 3 (E)s during the rush are sent to 179 instead of there — something I forgot to add to: 

6 hours ago, RR503 said:

Nope. No one takes the local from Manhattan/LIC/anywhere west of Roosevelt to FHills. Similarly, no one will take the local from anywhere beyond Kew Gardens to 179. Put differently, I’ve never seen a local arrive at Fhills with more than a few people inside. 

As for the availability of tracks at 179, I agree that helps. But, if you extend both services to 179 (which you’d need to do lest you end up with a much-worse Church Ave.), you end up with something on the order of 36tph (15 (F), 11 (M), 10 (R)) terminating at 179. Spread across two tracks, that’s 18 tph/track — or nearly what FHills does today. What’s more, if you have trains taking the “incorrect” inbound track at 179, there’s no way they can switch to the “correct” track when reentering, leading to confusion about where one’s train will arrive. And of course, this is to say nothing of the delays that come with willy-nilly merging at 169. 

So yes, a 179 extension would be nice as the (F) could lose some stops, and stop having to make that awful merge at 75, but I think to claim that the terminal situation would be any better than that of 71 is misleading. 

 

Edited by RR503

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