|
|
| Re: Old LIRR Rockaway Beach Branch (1252374) | |
 |
|
| Home > SubChat | |
[ Post a New Response | Return to the Index ]
|
Page 2 of 3 |
||
|
| (1252589) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Wed Oct 9 12:05:25 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Wed Oct 9 11:58:54 2013. http://en.wikipedia.org/wiki/Automation_of_the_New_York_City_Subway"allow trains to be operated at closer distances (slightly increasing capacity) " "way to increase capacity on lines that have already maxed out the capabilities of the current system." |
|
|
| (1252596) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Wed Oct 9 12:52:46 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Wed Oct 9 12:05:25 2013. "allow trains to be operated at closer distances (slightly increasing capacity) "How close trains can be operated depends on the follower's emergency braking rate. That's not a signal system parameter. The signal system is designed knowing what that braking rate is. "way to increase capacity on lines that have already maxed out the capabilities of the current system." Which lines are currently operating at more than 75% of their capacity? Hint. Here's a link to a TA document from nearly 60 years ago that shows the line capacity for the lines. |
|
|
| (1252598) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Wed Oct 9 13:16:45 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Wed Oct 9 12:52:46 2013. You are forgetting key-by went away. CBTC will partially compensate for it. |
|
|
(Sponsored) |
iPhone 6 (4.7 Inch) Premium PU Leather Wallet Case - Red w/ Floral Interior - by Notch-It |
|
| (1252603) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Mitch45 on Wed Oct 9 13:57:39 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Nilet on Tue Oct 8 15:18:20 2013. Not exactly. The government paid private companies to build it for them, in exchange for the right to operate it and charge fares. It wasn't until the 1920's that the City realized that the IRT and the BMT were making money and the City was getting stiffed on its share, giving rise to the IND. |
|
|
| (1252612) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Tony Clifton on Wed Oct 9 14:36:10 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Mitch45 on Wed Oct 9 13:57:39 2013. How is that an "exchange"? Are you sure you have the story right? |
|
|
| (1252621) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by GP38/R42 Chris on Wed Oct 9 15:53:01 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Nilet on Tue Oct 8 15:18:20 2013. Uhm, no. Not exactly. |
|
|
| (1252622) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by GP38/R42 Chris on Wed Oct 9 15:55:19 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by MainR3664 on Wed Oct 9 06:59:52 2013. I agree. But only it would only make sense for the LIRR if it was for the airport. The Subway already has three subway connections, the J line, the E line from Queens Blvd, and the A line. A higher speed LIRR to the airport would make sense. That said, for local traffic, the line would make much more sense as a subway line. |
|
|
| (1252627) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Wed Oct 9 16:36:32 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by MainR3664 on Wed Oct 9 06:59:52 2013. It gets down to this: you want comfort or passenger volume ? |
|
|
| (1252639) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by renee gil on Wed Oct 9 17:18:26 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Nilet on Tue Oct 8 15:18:20 2013. i think the dual contracts system were built with government dollars, same goes with the original 1904 subway from city hall loop to 145th/b'way. |
|
|
| (1252642) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Wed Oct 9 17:36:38 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Mitch45 on Wed Oct 9 13:57:39 2013. Actually, the IRT and BMT were NOT making money but were hamstrung by the city's refusal to allow the privates to raise the fare above a nickel. The gov't actually did build the dual contract portions of the IRT and BMT with the intention of having those companies operate them as part of their existing systems. At one point, the iRT took offense at the PSC allowing the BRT to operate the 4 Av subway in Bkln and backed out of the dual contract agreement. This gave rise to the construction of a lower portion of the Lex Av Subway below 42 St to connect the upper Lex to the BRT's Bway Subway. Also since the Lex, Jerome, Pelham and even the Wh Pl Rd Lines were built to the larger clearances of the BRT equipment, that would have meant that those lines with the possible exception of the Wh Pl Rd Line would go to the BRT. When the IRT realized that it would lose out on a lot of potential Bronx ridership by not having the operating rights to lines that could connect to its existing lines, it ceased complaining about not getting the 4 Av subway and settled for the E/Pky and Nostrand lines and reentered the Dual contracts thus getting back the Bronx lines that had been originally assigned to it. Many of the lines that are now part of the iND were originally intended to be built as extensions of the BRT/BMT but since mayor Hylan had a personal vendetta against the private companies especially the BRT and its successor the BMT, he insisted that the new lines be built as part of a new system operated by the city and independent of the 2 private companies hence the name "Independent Subway System" which after unification became the IND division of the NYCTS. Actually, after Hylan left office, the city decided it really didn't want to operate the new lines and since its dimensions were almost identical to the BMT's, offered them to the BMT. The BMT declined to operate the new lines unless it was allowed to raise the fare above 5 cents which the city would not allow it to do and since the new lines were substantially completed, the city found itself obligated to operate the new subway under the newly established Board of Transportation. |
|
|
| (1252647) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Wed Oct 9 18:09:00 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Wed Oct 9 13:16:45 2013. You are forgetting key-by went away.Not at all. Key-by is not necessary to achieve the capacities shown on the TA document. You can verify that for yourself. The block after a station is 600 ft long. You want the leader to pass this block before the follower enters the station. The 600 ft leader must travel 1200 ft to fulfill the first condition. It will take 12 seconds for the leader to accelerate to 30 mph at an acceleration of 2.5 mph/sec. The leader will have travelled 264 ft during the acceleration. The leader still needs to travel 936 ft at 30 mph. This will take an additional 21 seconds. This brings total time to 33 seconds. At this instant the follower is about to enter the station. The follower will see: a green aspect outside the station; a yellow aspect within the station and a red aspect at the station exit. The follower is travelling at 30 mph. The follower's service brakes decelerate at 2.5 mph/sec. The follower will apply the service brakes 264 feet from the station's end taking 12 seconds to do it. Prior to this the follower will have continued into the station at 30 mph for a distance of 336 ft. It will have taken the follower 8 seconds to travel this distance. The follower will have taken 20 seconds to enter the station and come to a complete stop. This allows 37 seconds of dwell time for the follower to maintain 90 second headways. The follower and his follower will never encounter anything but green aspects. You may also verify these leader's exit time and the follower's entry time with a stop watch. For the leader it's the time he starts moving to the time the tripper at the station exit goes up. Alternatively you may measure the time form when the leader starts moving to the time the signal at the station entrance turns green. For the follower's time you should measure the time from when the follower enters the station until he stops. You are going to have to take several measurements because there is great variablity among T/O's. If you are not mathematically challenged, you may see the effect increasing the acceleration and service braking rates to 4.0 mph/sec (like the Multi's, Bluebirds and PCC trolleys.) |
|
|
| (1252649) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Wed Oct 9 18:16:32 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Wed Oct 9 18:09:00 2013. While I would like to see PCC quality acceleration and deceleration, it would also be necessary to provide all such cars with PCC type track brakes for a more positive emergency brake application. |
|
|
| (1252654) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Wed Oct 9 18:33:03 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by randyo on Wed Oct 9 18:16:32 2013. I did allude to track brakes in another post.The point I was making is that 40 tph capacity is possible with Dual Contracts technology. Inasmuch as we do not schedule 75% of that capacity on any line, increasing capacity 40 tph to 44 tph isn't going to change anything. |
|
|
| (1252656) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Mitch45 on Wed Oct 9 18:42:36 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by randyo on Wed Oct 9 17:36:38 2013. A few thoughts."Actually, the IRT and BMT were NOT making money but were hamstrung by the city's refusal to allow the privates to raise the fare above a nickel." That didn't occur until after World War I, when inflation and higher labor and parts costs set in. In fact, the nickel fare was put into the contracts at the insistence of the traction companies, who were afraid that the city would demand that the fare be lowered once the public started to use the system in earnest. Before World War I, the IRT was very profitable. One other thing: the IRT was also hamstrung by the terms of its 1902 purchase of the elevated lines. The IRT owed the elevateds' stockholders a lot of money. "This gave rise to the construction of a lower portion of the Lex Av Subway below 42 St to connect the upper Lex to the BRT's Bway Subway." I don't think anything was actually built by the BRT on the Lexington line. I think the BRT's willingness to build the upper Lexington line was enough to get August Belmont back to the table. "Many of the lines that are now part of the iND were originally intended to be built as extensions of the BRT/BMT..." Are you referring to the Triborough subway expansion plan, which came before the Dual Contracts but was ultimately rejected by the PSC and the Courts? "Actually, after Hylan left office, the city decided it really didn't want to operate the new lines and since its dimensions were almost identical to the BMT's, offered them to the BMT. The BMT declined to operate the new lines unless it was allowed to raise the fare above 5 cents which the city would not allow it to do and since the new lines were substantially completed, the city found itself obligated to operate the new subway under the newly established Board of Transportation." I read somewhere that the City took bids from private companies to operate the IND and got just one offer, from the Oakdale Contracting Company, which didn't really want to pay the City anything. |
|
|
| (1252657) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Kriston Lewis on Wed Oct 9 18:47:18 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Nyctransitman on Tue Oct 8 17:03:43 2013. By the time that happens, we'll be using smartcards (MetroCard 2.0). Perhaps they can implement a touch in/touch out system or have conductors carry portable readers.That way you'd have one card for the entire region. |
|
|
| (1252667) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Wed Oct 9 19:35:29 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Wed Oct 9 18:33:03 2013. You are living in a 60 year old time warp.Equipment changed, speed limits changed, rules changed and YES killing key-by cut capacity, which is why the #7 can no longer run at 36 TPH like it did in the 1960's. CBTC can increase capacity, regardless of your opinions on the matter. |
|
|
| (1252669) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by italianstallion on Wed Oct 9 19:45:26 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Wed Oct 9 19:35:29 2013. I'm no expert, but why would the absence of keying-by affect capacity? If each train were on schedule, there would never be a need to key by. |
|
|
| (1252670) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Wed Oct 9 19:49:18 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by italianstallion on Wed Oct 9 19:45:26 2013. And when is each train exactly on schedule when they run 100 seconds apart ? |
|
|
| (1252677) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Edwards! on Wed Oct 9 20:14:26 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Wed Oct 9 19:35:29 2013. Stephen knows his stuff,dude..not saying you are completely wrong..but he HAS done the numbers on NUMEROUS OCCASIONS..even showing how CBTC has done nothing to "increase L train capacity" from the "old days"..sometimes,to learn..one must listen. |
|
|
| (1252680) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by SelkirkTMO on Wed Oct 9 20:21:08 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by italianstallion on Wed Oct 9 19:45:26 2013. As an artifact of the times when key-by was still permitted, there are several advantages. One is entering stations. If you're following your leader who is leaving the station and they continue to keep pulling away from you rather than you catching up with them, then you can enter a station on a red knowing that you can stop. In fact the IND did this on "station time" signals which would clear as a train was entering as another one was leaving.The other advantage is tightening up behind your leader in the case of congestion, stopping two car lengths away. It meant that when your leader started moving, you could also because you were in the same block with them, ever mindful that at some point, they'd have to stop and thus you kept your distance. Keying by did allow a little more capacity and for your follower to at least pull into the station behind you. |
|
|
| (1252682) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by SelkirkTMO on Wed Oct 9 20:36:13 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Wed Oct 9 19:35:29 2013. CBTC, because of its "moving blocks" concept pretty much does what we managed in the old days using key-by, but it's much safer. |
|
|
| (1252702) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Italianstallion on Wed Oct 9 22:40:43 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by SelkirkTMO on Wed Oct 9 20:21:08 2013. Thanks! |
|
|
| (1252703) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Wed Oct 9 22:50:53 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Wed Oct 9 19:35:29 2013. why the #7 can no longer run at 36 TPH like it did in the 1960's.That's easy. They don't have enough equipment. Here's the IRT fleet in 1969: 2923 cars; 2561 peak + 362 spares. 396 cars required for peak operation on the #7. Here's today's car assignments showing only 352 cars used on the #7. Here's a look at the fleet total of 2770 cars. That's down from 2923 back in the 1960's. |
|
|
| (1252704) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by SelkirkTMO on Wed Oct 9 23:12:17 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Italianstallion on Wed Oct 9 22:40:43 2013. You're welcome! I'm sure once Randy sees this, he'll elaborate further. |
|
|
| (1252710) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Michael549 on Wed Oct 9 23:55:23 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Wed Oct 9 11:56:22 2013. If their NTT trains had better acceleration and service braking rates to 4.0 mph/sec and the emergency braking rate to 7.0 mph/sec, line capacity would be raised to around 47 tph. It would take a new signal system to realize these capacity gains. CBTC might be a realistic and possibly cost effective option in that case.------------ I am usually under the impression that the NEWER subway cars are BETTER in many ways than the older subway cars. I am hoping that BETTER means better acceleration, better braking, better speed, better rider comfort and amenities, etc. Now whether any of that translates into having a suggested 47 trains per hour is a whole other question. It is really "wrong" to think that the newer subway cars are "better" than the older or oldest subway cars? Just wondering. Mike |
|
|
| (1252716) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 04:05:18 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by SelkirkTMO on Wed Oct 9 23:12:17 2013. Not this time. It was pretty well covered. |
|
|
| (1252718) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 04:13:53 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Mitch45 on Wed Oct 9 18:42:36 2013. The City actually built the Lex Line for the IRT's use but the IRT's unwillingness to cooperate with the dual contracts prompted the start of construction of the connection between the Bway Subway and the Lex. I have a copy of a 1913 PSC annual report that documents this. |
|
|
| (1252728) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Thu Oct 10 07:18:40 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Wed Oct 9 22:50:53 2013. You are mixing cause and effect,They also don't have the capacity to run 36 TPH, nor the demand. Some World's Fair R36's were removed in the 70's and never replaced. |
|
|
| (1252751) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Thu Oct 10 10:42:05 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Thu Oct 10 07:18:40 2013. They also don't have the capacity to run 36 TPH, nor the demand.You do not know whether the line can still handle 36 tph unless you try it. They don't have enough trainsets to try it. There tests that can be performed to measure the signal system's maximum service level without actually trying it. They involve using a stop watch at the intermediate stations that I described earlier. The Flushing Line could still handle 40 tph, if they had the trainsets. The number of peak hour passengers has declined dramatically. The peak hour inbound figures are: 48,980 (1971) and 19,241 (2011). I agree they no longer need 36 tph. Perhaps you could explain that in the absence of demand for increased maximum service levels why NYCT is currently investing in a signal system that they claim will boost maximum service levels. They currently do not need the capacity that already exists. Why are they spending a lot of money to boost unused capacity. Any increased capacity will be unused because they will not be increasing the number of trainsets. This is potentially a big problem with CBTC because CBTC requires specially equipped trainsets. Should demand increase to 1971 levels, NYCT will not be able to divert equipment from other lines to provide additional service. |
|
|
| (1252757) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Thu Oct 10 11:48:44 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Thu Oct 10 10:42:05 2013. And how do you explain the fact that trains stop, creep, and crawl in the rush from Grand Central to Times Square with 28 TPH, and arrivaing Main Street is another nightmare ? The crews already fall back one train in Times Square.If you are so sure of yourself that CBTC does nothing for capacity, I advise you write up your thoughts on Wikipedia and tell some of the annotated sources that they are wrong. |
|
|
| (1252767) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Thu Oct 10 12:35:13 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by SelkirkTMO on Wed Oct 9 20:21:08 2013. Let me present a dissenting opinion.As an artifact of the times when key-by was still permitted, there are several advantages. One is entering stations. If you're following your leader who is leaving the station and they continue to keep pulling away from you rather than you catching up with them, then you can enter a station on a red knowing that you can stop. In fact the IND did this on "station time" signals which would clear as a train was entering as another one was leaving. Did the operation you described reduce or increase headway? The follower who has keyed by will proceed at about 5 mph because there are no trippers to prevent a collision. The follower is 120 ft behind the leader and starts the instant the leader starts moving. It takes the follower 2 seconds to reach 5 mph and the follower has traveled 7 ft. Assuming 2.5 mph/sec for the service braking rate, the T/O will have to apply the brakes 7 ft before the mark. The train will travel for 600 + 120 - 7 - 7 = 706 ft at 5 mph. (station length + dist to leader - accel dist - brake dist). This will take 96 sec. The follower will have taken 100 seconds to come to a complete stop after the leader has started moving with keying by. Let's assume the follower does not key by. Instead the follower stops at the red signal that is 300 ft before the station entrance. The follower will wait for that signal to turn green before proceeding. He will then accelerate to 30 mph, enter the station at 30 mph and operate as if the leader did not cause the follower to stop. The signal the follower is waiting for will turn green, when the leader has travelled 600 ft (cleared the station). As mentioned in the previous post the leader will travel 264 ft in 12 seconds while accelerating to 30 mph. The leader will the will take an additional 8 seconds to clear the station, bringing the total up to 20 seconds. The follower will then accelerate to 30 mph in 12 seconds and 264 feet. The follower will take an additional 1 second to reach the station entrance @ 30 mph. From the previous timing post, the follower will come to a stop in the station in 20 seconds after entering it at 30 mph. The follower's total time from starting was 33 seconds. The total elapsed time from when the leader started moving is 53 seconds. So, it's 53 seconds without keying by vs. 96 seconds with keying by. Contrary to popular belief, keying by does not increase service levels - it destroys them. |
|
|
| (1252794) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by SelkirkTMO on Thu Oct 10 14:22:48 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by randyo on Thu Oct 10 04:05:18 2013. Cool! Yeah, always got a kick out of key-by's when I was given the chance to do them. :)I was figuring you might have added the common situation where one track circuit had failed where we had to pass red automatics that were never going to clear and similar situations. |
|
|
| (1252804) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 15:09:21 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by SelkirkTMO on Thu Oct 10 14:22:48 2013. That really doesn't have any bearing on the effect of keying by on train throughput. |
|
|
| (1252805) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by SelkirkTMO on Thu Oct 10 15:11:35 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by randyo on Thu Oct 10 15:09:21 2013. True ... |
|
|
| (1252806) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 15:12:57 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Thu Oct 10 12:35:13 2013. The problem is that even if the leading train has cleared the station, it would not be safe operation for the following T/O to accelerate to 30 MPH so the following train will likely proceed at somewhere between 10 to 15 MPH if that so keying by still has the advantage. |
|
|
| (1252807) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 15:16:13 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Thu Oct 10 11:48:44 2013. Unless it's changed since I was in scheduling, crews drop back 2 at T/SQ in rush hours and 1 the rest of the time until late PM, midnights and weekends when they take the same train back. |
|
|
| (1252816) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Tony Clifton on Thu Oct 10 15:32:49 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by randyo on Thu Oct 10 15:12:57 2013. Why wouldn't it be safe? |
|
|
| (1252821) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 15:37:06 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Tony Clifton on Thu Oct 10 15:32:49 2013. The way the present signal system clears, there is usually not enough distance between the rear of a train and the signal immediately behind it. Should a train stop immediately pas it and the following train accelerate to something close to 30 MPH the potential exists for a rear end collision should any sort of brake failure occur. Having been a M/M ad later a T/D and trainmaster, I have personally observed such situations. |
|
|
| (1252823) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by SelkirkTMO on Thu Oct 10 15:50:06 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Thu Oct 10 12:35:13 2013. I'll go with where Randy went, and simply add that keying by was never intended to improve service, it was a means of maintaining service. It allowed a train following the train which keyed by the opportunity to platform at the station behind that train. If you're in a position of keying by in order to close in on your leader, the railroad is already jacked up or your signals ahead would be clear for you.Keying by is also necessary when there's a bad track circuit ahead and you're presented with a red with the tracks ahead actually clear. So in this case, it would help service by allowing it to run at all. In my case, I'm thinking of a common keyby location, leaving 7th Avenue northbound into 59/CC for instance. If the train ahead of you on the ramp to 59/CC is already moving, keying by (with permission) at the exit of 7th Avenue N/B allows you to clear the stop, work your way up the ramp where you'd be held anyway, and permit the train behind you to enter 7th Avenue. Another spot was Parkside Place on the Brighton N/B where trains were merging to head towards DeKalb. But normally, keying by was done where there was a red automatic with tracks clear ahead of it due to a signal or track circuit problem. |
|
|
| (1252825) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Thu Oct 10 16:31:11 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by randyo on Thu Oct 10 15:16:13 2013. I they did 36 TPH, they would have to drop back 3 trains ? |
|
|
| (1252828) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Thu Oct 10 16:40:38 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by randyo on Thu Oct 10 15:12:57 2013. The problem is that even if the leading train has cleared the station, it would not be safe operation for the following T/O to accelerate to 30 MPHI'm assuming you are referring to the second scenario - follower stops for red signal 300 feet before station and proceeds when that signal turns green (not yellow). There is always a tripper at least 300 feet behind the leader's rear under this scenario. The stopping distance using service brakes of 2.5 mph/sec is 264 ft. The stopping distance with emergency brakes of 3.2 mph/sec is even less. The service brakes alone would stop the follower 36 ft short of the leader's rear. |
|
|
| (1252831) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Thu Oct 10 16:51:44 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by randyo on Thu Oct 10 15:37:06 2013. there is usually not enough distance between the rear of a train and the signal immediately behind it.I agree. The scenario I presented has two red signals behind the leader's rear. The signal further from the leader's rear is at least 300 ft distant from the leader's rear. Moreover this signal has its tripper up, unlike the signal immediately behind the leader's rear. The emergency stopping distance is 208 ft; the service brake stopping distance is 264 ft. Both miss the leader. |
|
|
| (1252840) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Stephen Bauman on Thu Oct 10 17:22:11 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Thu Oct 10 11:48:44 2013. how do you explain the fact that trains stop, creep, and crawl in the rush from Grand Central to Times Square with 28 TPH,That's pretty simple. The TA decided to improve on time performance by increasing scheduled run times. The local run time was 28 minutes after the R33/36WF's were introduced. It's now 33 minutes. The trouble is about 80% of the trains make the run in 28 minutes. The schedule for trains leaving Times Sq. assumes all trains take 33 minutes to get there. So, trains have to wait outside Times Sq. waiting for a train to leave. Another source for delays has been fixed. The dispatchers' clocks were not sychronized. There was a 2 to 3 minute difference in the clocks between Main St. and Times Sq. arrivaing Main Street is another nightmare The Flushing Line has been my line for more than 50 years. I was able to associate a fairly high probability of delay with the day of the week. I could count on delays Friday evening. If there were a holiday weekend, trains were backed up getting into Willets Pt. My conjecture is that many crew members figured out a way of going AWOL without being caught. |
|
|
| (1252849) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 18:21:45 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by SelkirkTMO on Thu Oct 10 15:50:06 2013. There are a few places on the system where keying by even when it was allowed in most places was not. One that you cite in particular is lvg 7 Av/53 St N/B. There was a sign adjacent to the signal which read "If this signal is red, STOP. Call 59 St tower." there was a phone by that signal connected directly to 59 St tower and M/M would have to call to ascertain if there might be a train just beyond the curve out of the M/M's vision. Another is the leaving signal at the N/E of Ft Hamilton Pky on the West End line which doesn't have the IJ in the proper location to permit a key by. The latter was due to a collision between an M train which due to track work had to relay at 62 St instead of using the 9 Av middle and at the time a B train which had stopped just outside the M/M's range of vision. |
|
|
| (1252852) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 18:23:34 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Thu Oct 10 16:31:11 2013. Probably not. Even with such a level of service, 2 trains should be enough. |
|
|
| (1252853) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 18:26:43 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Thu Oct 10 16:40:38 2013. Actually, there is not always a tripper 300 ft behind the rear of at train when a station is involved which is why the rule for skipping stations requires the speed at the lvg end of the station to be no more than 15 MPH. |
|
|
| (1252854) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by randyo on Thu Oct 10 18:28:38 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Joe V on Thu Oct 10 16:31:11 2013. Probably not. Even with such a level of service, 2 trains should be enough. |
|
|
| (1252858) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Tony Clifton on Thu Oct 10 18:42:49 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Stephen Bauman on Thu Oct 10 16:51:44 2013. Thank you. I knew he couldn't be talking about the same situation you were already talking about. |
|
|
| (1252919) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Wallyhorse on Fri Oct 11 06:57:15 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by MainR3664 on Tue Oct 8 16:15:02 2013. The real problem as noted previously is that some of them apparently have property that encroaches the LIRR ROW illegally. That is what they are likely REALLY worried about. |
|
|
| (1252932) | |
Re: Old LIRR Rockaway Beach Branch |
|
|
Posted by Joe V on Fri Oct 11 08:35:42 2013, in response to Re: Old LIRR Rockaway Beach Branch, posted by Wallyhorse on Fri Oct 11 06:57:15 2013. They could all be offered Pella windows to soundproof their bedrooms, which would increase their selling price and cut their heating bill, and the idiots would still refuse it. |
|
|
|
Page 2 of 3 |
||
