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| (1499825) | |
The Return Of "Rapid" Transit ? |
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Posted by Bill Newkirk on Sat Jan 12 17:56:50 2019 Source: e-mail from a friendOver the past several months, a reutilized 10-car subway train has been patrolling nearly every mile of subway track, carrying NYC Transit’s recently formed Subway, Performance, Evaluation, Education, and Development (SPEED) unit, a team of transit personnel armed with radar guns and other test equipment. No, the radar-packing SPEED Unit isn’t looking for speeders. Just the opposite. They’re looking for slow spots in the subway system—stretches of track where planners can safely squeeze more speed out of the current signals and trains. So far, their work has led to a near doubling of some speed limits on five stretches of the N/R lines in Brooklyn, from 15-mph zones to 20 or 30 mph, with additional increases approved and soon to be rolled out, bringing millions of customers a speedier ride. Years of Accumulated Go-Slows The work of the SPEED Unit is part of a broader effort known as the “Save Safe Seconds” campaign, initiated by Senior Vice President for Subways Sally Librera and NYC Transit President Andy Byford as part of the Fast Forward Plan for modernizing the entire transit system. The goal is to locate those spots within the subway system where many factors have led to speed restrictions well below the safe levels for today’s trains and track geometry. Some of those factors date back to the subway’s earliest operations over 100 years ago. One longtime basic safety measure, for example, is civil speed restrictions, with posted speed limits and signs much like those on a highway. Another is grade time signals or “timer signals” with fail-safe timing devices set to trip the emergency brakes if a train passes at a higher-than-allowed speed. Over the years, the allowable speed limits weren’t always updated to reflect safety advances in car design and track geometry. Meanwhile, spurred in part by two fatal accidents in the 1990s, the number of timer signals would eventually grow to about 2,000 systemwide. Finding the Right Balance There’s little doubt that customers want faster service. But the demand for speed must be weighed against the absolute priority of safety. “Safety is always our top priority,” Byford said in a recent press statement, “and we’re working hard to maximize our subway’s potential within the boundaries of stringent safety standards.” He went on to note that some timer signals have become miscalibrated over time, forcing trains to go slower than they need to. “We’re taking a fresh look, with no compromise to safety, at how to reduce delays and get people to their destinations sooner.” Enter the SPEED Unit. A collaborative effort between transit departments, as well as union officials, the new unit is headed up by Barry Greenblatt, vice president and chief officer of service delivery, and Philip Dominguez, train service supervisor, both of NYC Transit. Since late August, the SPEED Unit has already reviewed 665 miles of track, tested 2,000 timer signals, and fixed over 250 slow signals. In addition to the five operating increases on the N/R lines, 29 more speed increases have been approved by a safety committee and are currently being rolled out. By springtime, agency planners estimate, nearly 100 locations across all boroughs will see safe upgrades in the allowed train speeds, resulting in better performance all around. Contributing to the Speed Unit and the Save Safe Seconds campaign is an ongoing effort to elicit fresh ideas for improving the subway system from frontline employees, who frequently mentioned timer signals. While many factors can lead to slower or delayed subway service, this is one system improvement that can be done safely and can be done now. The SPEED Unit is doing just that. |
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| (1499826) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Jackson Park B Train on Sat Jan 12 18:08:49 2019, in response to The Return Of "Rapid" Transit ?, posted by Bill Newkirk on Sat Jan 12 17:56:50 2019. Hurray!!! A good start. Someone needs to send Byford the 1954 TPH capacity document so he sees what has been lost. |
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| (1499827) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Catfish 44 on Sat Jan 12 18:16:20 2019, in response to The Return Of "Rapid" Transit ?, posted by Bill Newkirk on Sat Jan 12 17:56:50 2019. What kind of 10 car train are they using for this project I wonder |
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| (1499830) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Stephen Bauman on Sat Jan 12 18:33:34 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Jackson Park B Train on Sat Jan 12 18:08:49 2019. Someone needs to send Byford the 1954 TPH capacity document so he sees what has been lost.I gave him a copy, when he gave his first Fast Forward presentation. He's not interested in past performance. A more relevant document would be the travel times between terminals. These were raised to make the on time performance metric look better. |
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| (1499831) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Kevin from Midwood on Sat Jan 12 18:48:08 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Catfish 44 on Sat Jan 12 18:16:20 2019. There has to be more than one. In the video here it's an R-42 set led by car # 4804, a no-go on the A Division. |
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| (1499841) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Steve B-8AVEXP on Sat Jan 12 23:27:06 2019, in response to The Return Of "Rapid" Transit ?, posted by Bill Newkirk on Sat Jan 12 17:56:50 2019. "More rapid and less leisurely." |
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| (1499846) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by MTA T on Sun Jan 13 11:12:50 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Kevin from Midwood on Sat Jan 12 18:48:08 2019. Just anything. I've seen videos of R32s, of R143s, of R160s. |
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| (1499855) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Dan on Sun Jan 13 14:22:07 2019, in response to The Return Of "Rapid" Transit ?, posted by Bill Newkirk on Sat Jan 12 17:56:50 2019. Will the SIR be included in this program? |
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| (1499859) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by r33/r36 mainline on Sun Jan 13 15:05:32 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Dan on Sun Jan 13 14:22:07 2019. No need for them too, they seem to still have field shunting installed on those SIR 44s. Plus the line is 99% straight and uses a different signal system. |
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| (1499861) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by tunnelrat on Sun Jan 13 15:37:21 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by r33/r36 mainline on Sun Jan 13 15:05:32 2019. ` |
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| (1499902) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Steamdriven on Sun Jan 13 22:36:44 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Stephen Bauman on Sat Jan 12 18:33:34 2019. A billion or so in signal upgrades to do almost as well as 1954 is quite reasonable, is it not? |
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| (1499904) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by MainR3664 on Sun Jan 13 22:45:45 2019, in response to The Return Of "Rapid" Transit ?, posted by Bill Newkirk on Sat Jan 12 17:56:50 2019. I hope this works. The first accident that happens, they'll blame this initiative (right or wrongly), and we'll be back to a crawl.Overall, I like this plan Seems a bit more practical than spending billions on CBTC everywhere... |
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| (1499906) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Jackson Park B Train on Sun Jan 13 23:19:56 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by MainR3664 on Sun Jan 13 22:45:45 2019. Unless the CBTC vendors all die, they'll get their pieces of the action whether needed or not. |
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| (1499916) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by FormerVanWyckBlvdUser on Mon Jan 14 00:10:40 2019, in response to The Return Of "Rapid" Transit ?, posted by Bill Newkirk on Sat Jan 12 17:56:50 2019. Can we get some examples of where the speed limit has been increased? And/or timers removed/fixed? |
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| (1499928) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by MainR3664 on Mon Jan 14 06:53:38 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Jackson Park B Train on Sun Jan 13 23:19:56 2019. Oh, I agree. There will be no stopping this "progress"- CBTC or some version thereof is the way they're going- for better or worse.I guess what I'm saying is that those of us here can see that an investment of billions in CBTC isn't really what's needed; they can make significant improvements with proper use, placement, and maintenance of the existing signal system. |
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| (1499954) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Michael549 on Mon Jan 14 12:41:03 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by MainR3664 on Mon Jan 14 06:53:38 2019. From a previous message:"I guess what I'm saying is that those of us here can see that an investment of billions in CBTC isn't really what's needed; they can make significant improvements with proper use, placement, and maintenance of the existing signal system." Help me out here - as I understand it: The current signal system is a kind of analog computer with track detection elements serving as a kind of input sensors, the home signals and stands as a kind of output, and switch machines and related diagram board serving as a kind a "command control center" aka keyboard & output screen. This analog system as several (or many) features built into it - opposing tracks can not be switched onto the same track, trains can be kept at certain distances, switches can not move while a train is moving over the switch, etc. The basic problems are: a) Analog computers are not made anymore - the world has long since moved on to digital computers b) Many of the components - mechanical electrical relays and related equipment are not longer being made, spare parts have to be cobbled together - which is not sustainable over the long period c) Newer desired features are not that easily to implement - such as automated train control, identification, etc. d) Problems with the current system are not that easy to fix -- Or at least that is what I understood as the reason to go towad CBTC. Mike |
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| (1499956) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Jackson Park B Train on Mon Jan 14 13:38:51 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Michael549 on Mon Jan 14 12:41:03 2019. And if ANY of the CBTC hardware were as robustly built as the "obsolete" equipment, you might convince me. I have read comments by people I trust that recently rewired parts of the signalsystem are less reliable that the ancient stuff. Show me a "digital camera" with the integrity of the top end film cameras of 50 years ago. (let alone my grandfather's 1936 Leica which still works) Of course, the argument is that the modern hardware need not last very long because the technology will have made it obsolete before it fails. Soyou pay the high labor cost and rider inconvenience of having to build the system over again.And, as a reminder, CTA was able to operate at less than 2 minute headways with the "obsolete" "analog" signalling system as built in the 40s into the 70s. No part of the BART with its "space age" computer driven ATC/ATO has eversustained such tight headways. They hope to move from 20 TPH to 24 TPH with their fouth generation of computers. |
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Re: The Return Of ''Rapid'' Transit ? |
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Posted by randyo on Mon Jan 14 16:45:27 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Michael549 on Mon Jan 14 12:41:03 2019. Then what sort of components are being used for the new installation of conventional block signals? |
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| (1500000) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Steve B-8AVEXP on Mon Jan 14 20:17:03 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Jackson Park B Train on Mon Jan 14 13:38:51 2019. Hey - my grandfather had a couple of 1936 Leicas! He gave one of them to my father as a wedding gift. I have it now and it still works - not that I use it much now.As a matter of fact, my grandfather's photos of his 1936 visit to the US were taken with a Leica. |
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| (1500002) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Michael549 on Mon Jan 14 20:23:00 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by randyo on Mon Jan 14 16:45:27 2019. Jackson Park B Train & randyoAgain, what I stated was what I understood to be the reasons to go toward CBTC. Mike |
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| (1500008) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Stephen Bauman on Mon Jan 14 22:31:56 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Michael549 on Mon Jan 14 12:41:03 2019. The current signal system is a kind of analog computerIt's digital. One must separate the algorithms from how they are implemented. Current systems use track circuits to determine train location. The train locations determined by these track circuits are then processed by a distributed digital network to prevent collisions and many other possible functions. CBTC stands for Communications Based Train Control. The train has an independent means of knowing its position. The train then communicates its position to the control system. The control system responds by issuing a speed command to the train. That's the algorithmic difference between CBTC and existing block systems. There's no difference in service level capacity, between the two systems. Service level capacity is determined by the operating characteristics of the rolling stock: braking and acceleration rates. The control for CBTC tends to be implemented by computers because CBTC is newer. Block systems, being older, tend to be implemented by hard wired relay logic. However, there's nothing to prevent block system control to be implemented by computers nor CBTC control to be implemented by hard wired relay logic. One big problem for both computer and relay based systems is the availability of spare parts. The railroad industry uses a special type of relay which they call a vital relay. It's used only within the railroad industry. Vital relays are difficult to find because the railroad industry is too tiny to make it worth manufacturing them. There's an equally difficult problem in finding exact replacement parts for computers. The technology turnover is so rapid that products rarely last 3 years before something better replaces them. Finding an exact replacement on a scale required for NYCT after 5 or 10 years becomes nearly impossible. (The latest embedded computer is something called the Raspberry Pi 3. It came out within the last few months. Its manufacturers are promising to continue production until 2022.) There are strategies for managing technological innovation. Most companies, including the MTA, are not following them. |
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| (1500012) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by randyo on Tue Jan 15 00:07:49 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Michael549 on Mon Jan 14 20:23:00 2019. That info may have come from someone who knows less about signaling than we do. |
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Re: The Return Of ''Rapid'' Transit ? |
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Posted by randyo on Tue Jan 15 00:16:47 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Stephen Bauman on Mon Jan 14 22:31:56 2019. That sounds reasonable if not satisfactory. |
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Re: The Return Of ''Rapid'' Transit ? |
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Posted by Jackson Park B Train on Tue Jan 15 00:22:36 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by randyo on Tue Jan 15 00:07:49 2019. Michael might be right. I, who clearly enjoy this digital machine which lets us converse, am unconvinced about CBTC, ATC, ATO, because I live in BART and Muni country. BART's ATO computers were so flaky that the Cal PUC forced to install staffed "towers" on each platform who communicated via telephone to create manual block operation. After a while an outside consultant notioced that the "next train arrival system" actually did work and the systems were interconnected. After a couple newer generations of hardware, the system mostly works. Of course on extra warm days some of the wayside equipment overheats and we get "switching" roblems at Daly City which is both a through and terminal station.The former BART flack, Mike Healy described how early on they would deploy sacks of ice cubes... I am sure better hardware exists and is even marketed to transit agencies in the US, but the stuff used by my local agencies is not a shining example. |
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| (1500018) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Jackson Park B Train on Tue Jan 15 00:27:53 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Stephen Bauman on Mon Jan 14 22:31:56 2019. thanks for a clear explanation. and, the, of course, there is the issue of proprietary v multi platform. |
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| (1500026) | |
Re: The Return Of ''Rapid'' Transit ? |
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Posted by Stephen Bauman on Tue Jan 15 05:47:55 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Jackson Park B Train on Tue Jan 15 00:27:53 2019. there is the issue of proprietary v multi platform [open source].That's one of the items in "managing technological innovation". |
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Re: The Return Of ''Rapid'' Transit ? |
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Posted by Michael549 on Tue Jan 15 15:57:25 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Stephen Bauman on Tue Jan 15 05:47:55 2019. Let me re-phrase myself by using the paragraphs that you have typed:The analog system that I was referring to: "Block systems, being older, tend to be implemented by hard wired relay logic." Re-phrased text - The signal system of the 1920-1930's & 1940's was a kind of analog computer with track detection elements serving as a kind of input sensors, the home signals and stands as a kind of output, and switch machines and related diagram board serving as a kind a "command control center" aka keyboard & output screen. This analog system has several (or many) features built into it - opposing tracks can not be switched onto the same track, trains can be kept at certain distances, switches can not move while a train is moving over the switch, etc. --- Please note that I used the phrase, "current signal system" because that was the information given out in an MTA video concerning the behind the scenes look at the West 4th Street station complex and the equipment still in use that are many decades old. They explained in the video that sometimes older parts have to be re-wired or cobbled together because getting newer parts is difficult or not being made. --- I do not try to make this stuff up. When I go to the NYC Transit Museum and look at the model board and the track switch machine - that's the image that I have of the "old stuff." (I am not "allowed" into the newer tower rooms. I used to stand outside the tower room at City Hall station staring into the room, so now they have reflective glass. LOL! Ha! Ha!) --- I agree with you about computer components and the nature of change. Just try today to buy a brand new computer with a 3.5 floppy drive! Mike |
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Re: The Return Of ''Rapid'' Transit ? |
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Posted by Stephen Bauman on Tue Jan 15 23:45:50 2019, in response to Re: The Return Of ''Rapid'' Transit ?, posted by Michael549 on Tue Jan 15 15:57:25 2019. The signal system of the 1920-1930's & 1940's was a kind of analog computerAn analog circuit is one where inputs and outputs can have continuous values. Mathematically, for all values x0 < x1 there exists a value x such that x0 < x < x1. track detection elements serving as a kind of input sensors, track detection circuits are the very embodiment of digital sensors that can take on only 2 values: train present or train absent. These are typically represented by 0 volts for train present and some voltage > 0 for train absent. Analog computers are composed of operational amplifiers and integrators that are wired together. The connections, op amps and integrators are designed to solve simultaneous differential equations to an excitation derived from a signal generator. That's nothing like what the "current" or any signal system does, regardless of its age. |
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