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  • Newsday - LIRR brings on new signaling system

  • Discussion of the past and present operations of the Long Island Rail Road.
Discussion of the past and present operations of the Long Island Rail Road.

Moderator: Liquidcamphor

 #1501648  by Backshophoss
 
So LIRR follows MN into total reliance on Cab signals with ACSES with no wayside signal except at Control points and the few remaining towers!
This will come back to bite them some time down the road.
 #1501656  by workextra
 
Everyone is entitled to and option, but I believe that if those who operate the trains should supersede they of anyone political leader or community activist or valued customer when it comes to train movement and the signal system.

There for; in LIRR Jargon, the “409” concept is the best operationally- cost is non issue as LEDs and wide spread umindistry use of left of track signals and no bridges needed except in 3/more track territory.
We should be standardizing not replacing our railroad with a FRA test play ground.

G-heads on all mainline and branches off the mainline.
Safetrans on on southern routes and branches off the Montauk/Atlantic.

Thought the head is different, the aspect is the same and therefore is standard.
This practice would differentiate the 2 main divisions north shore and south shore from one another as well. That would satisfy the “dumb or down” politicians who need it fed to them.


409 would allow the LIRR to down right operate a tight schedule and keep trains moving w/o delay if a cab signal failed enroute, and such MAS would be 59MPH. governed by fixed signal indication.
Benefits include trains being kept on time or close to schedules and no needless delays establishing ACBs and reduced speeds down to 30mph.
Fact is clear. speed signals with fixed wayside ABS is the only way forward for such a dense operation as LIRR.
ASC without wayside ABS Does work but is a limiting factor.
If I’m wrong so be it. I don’t see LIRRs 410 concept realistic regardless of how long they used it.
Notice how the old guard never dropped the automatics bwtween Jay and Harold. Think delays are bad now?
 #1501663  by Head-end View
 
It's very interesting to read here the very similar opinions and comments to what was seen on the SEPTA forum some years back when they went with go/no-go signals on some of their branches. Their engineers had the same concerns, especially about the lack of info with this type of signaling. But I haven't seen anything in recent years about any more problems associated with that system.

One interesting thing on SEPTA was they continued to use full-size signals, masts and bridges instead of going to all dwarf signals, and their cab-proceed aspect is flashing-green over red.

Even without being a railroad employee, I would have to agree in principle with those who say that having multiple different types of signal systems in use on the same railroad might be confusing and potentially dangerous. Let's hope it all works out.
Last edited by Head-end View on Sun Feb 24, 2019 9:45 pm, edited 1 time in total.
 #1501665  by DaveBarraza
 
Kelly&Kelly wrote:This is the fruit of the political environment that government ownership and political patronage brings to the system. An idea comes to the table, maybe from India, maybe from a consultant who never did railroad work before. Rerhaps from some guy who ran subways. It's adopted and installed in a new place. Then an election brings another political party in control and with it comes a new troupe of management, from the NYC Sanitation Department perhaps, or maybe from the Canadian Railways. Here comes a new signal system added to the Book of Rules.
MNCR converted to go/no-go based primarily on one person, Dave Malle, a career Engineer for MNCR and it predecessors. He was the son of the NY Central's Chief Engineer of Grand Central Terminal. RAS on LIRR was advocated for years by career Engineers at LIRR, two Italian guys from Long Island, Vic and Tony.

The Governor was heavily involved with Farmingdale to KO after the job was awarded and in progress, but I don't think Albany had anything to do with writing the contract specifications.


I completely agree with you about *way* too many aspect systems currently in use on the LIRR.

1) Zone A Amtrak aspects - no real way around that, LIRR is a guest there.
2) Position Light Aspects
3) Color Light Aspects - descended from the Position Light rules, they mostly line up with Amtrak
4) Low Home Signals at Jay/Hall part of the Color Light system above but they look almost exactly like:
5) RAS signals - also ground mounted (except for a few that are up on poles, which look pretty funny)

I give credit to the Engineers who keep it all straight.
 #1501667  by DaveBarraza
 
I like 409 as well; heck I like position lights for that matter.

I think once LIRR went to Color Light that was the right way to go - the underlying signal rules did not change and it lined up almost exactly with Zone A. If they were going to change to RAS, it should have been done *instead* of going with the Color Lights. Now it's really too late, they've already invested in the color lights and it's a bad idea to add a completely new aspect system... Keep it Simple!!!
 #1501684  by Absolute-Limited Advance-Approach
 
DaveBarraza wrote:
The RAS aspect system does have distinct aspects for Slow and Restricting, (298C and 298D). I imagine this choice was made because those two rules can have the same speed code - although I believe it is allowable to get up to 30 in the cab if the signal displays slow, that might be a recent change.
While Slow proceed, Restricting Proceed and Restricting (bonus points if anyone can correctly explain the difference between the two) do exist, I have yet to see a slow proceed in the field and I haven't yet had an explanation on when the signal would be displayed. For the most part its Proceed, Restricting and Stop Signal.
DaveBarraza wrote: This may be an actual advantage of the RAS system (or Rule 410 area in general): The ASC speed downgrades are computed to give the highest safe speed for the longest allowable time/distance - which helps throughput. Observant engineers will tend to "preact" to the code change points that they encounter every day, which leads to very smooth operation. I can't think of any system that makes a less talented Engineer drive better... :-)
Those two things contradict in my experience, as a quick example, the curve on the Atlantic Branch into Hall interlocking is good for 30, and is protected by the ASC. You get a 30 code well in advance of the point of restriction such that you are at 30mph before you reach the baseball field, well outside of normal braking distance. On top of that, if you want to run a smooth train you have to slow before you reach the impedance box, in reality this just leads to slower operation. It's not 'better' driving, it forces ultra conservative operation which costs OTP. If the code points were 100% synced to braking distance, then maybe. As it stands they are set for the worst performing train which negates the advantages in agility the MU fleet has. Another thing to consider is that if the speed of the curve does not match what the ASC can present you automatically leads to an inefficiency, in a diesel most curves will code you to 38mph, even if its good for 50. So the system is not set on millimeter precision and you often have to go well underspeed to avoid being penalized by it. NYCT let this issue go too far. Hopefully PTC will be designed to avoid some of these issues.

DaveBarraza wrote:Agree that any hard braking could result in "passengers-off-balance." This is not unlike the current situation in Rule 410 territory which has existed on LIRR for some time, no? (possibly why the beers used to be served in a cup with a straw?!?)...

To address the point of 410, and the real detriment of blind driving is that the Train is driving the Engineer who becomes a passive participant in the safety of the equipment. In a lot of situations it is detrimental to the equipment to allow the brakes to apply in full service. In adverse conditions the wheels will lock up, or at the very least cause a slide. The fact that an Engineer cannot always anticipate a code drop and will get a harash application is what contributes to flat spots and fleet shortages.

In 410 straight run territory you have your time table and the signal at the last interlocking to give you an inkling of whether the ASC drop is a code drop, or train ahead.

With RAS there is no way to know if the 40 code is setting up a diverging route or if the block ahead is occupied, so you have to assume the worst.
 #1501730  by fcqjx
 
Interesting discussion. Any "civilians" who want to see what LIRR Engineers and Conductors have to qualify on in regards to signals can get the signal rules (and more) on the NTSB web site's supporting documents for the January 2017 Brooklyn bumper block crash; these don't include the new RAS signals discussed here.

And if you think this is bad just wait until ACSES starts being used; it's basically an almost independent system that handles speed restrictions based on a distance-based speed reduction curve that must not be exceeded to avoid a penalty brake application. I've made a bunch of trips on SEPTA's system and have experienced a number of penalty brake stops. If you think scheduling and smooth operation take a hit with RAS just imagine when you overload ACSES on top of that.

BTW while on this topic I have 3 technical question about LIRR's ASC system: 1. Does LIRR use 100Hz or 91 2/3 Hz as the code carrier in Zone C? 2. In Zone A does Amtrak make use of any of the 250 Hz carrier codes from A interlocking east up to Harold, and if so, does LIRR receive and decode them? 3. Reading version 5.0 of LIRR's PTCIP (public, redacted version) A narrative section states that the ESA trackage will be using a 250 HZ system. Wondering just how this squares with the answer to the preceding questions.
 #1501744  by Kelly&Kelly
 
Just as reference:
...RAS on the LIRR was advocated for years by career Engineers at LIRR, two Italian guys from Long Island, Vic and Tony.
These were not Locomotive Engineers, but signal engineers. The opinions of the transportation department and its Locomotive Engineers were never sought, and when they were made known, they were challenged to the point of getting some people in the Signal Department removed.
 #1501783  by Absolute-Limited Advance-Approach
 
DaveBarraza wrote:
The RAS aspect system does have distinct aspects for Slow and Restricting, (298C and 298D). I imagine this choice was made because those two rules can have the same speed code - although I believe it is allowable to get up to 30 in the cab if the signal displays slow, that might be a recent change.
While Slow proceed, Restricting Proceed and Restricting (bonus points if anyone can correctly explain the difference between the two) do exist, I have yet to see a slow proceed in the field and I haven't yet had an explanation on when the signal would be displayed. For the most part its Proceed, Restricting and Stop Signal.
DaveBarraza wrote: This may be an actual advantage of the RAS system (or Rule 410 area in general): The ASC speed downgrades are computed to give the highest safe speed for the longest allowable time/distance - which helps throughput. Observant engineers will tend to "preact" to the code change points that they encounter every day, which leads to very smooth operation. I can't think of any system that makes a less talented Engineer drive better... :-)
Those two things contradict in my experience, as a quick example, the curve on the Atlantic Branch into Hall interlocking is good for 30, and is protected by the ASC. You get a 30 code well in advance of the point of restriction such that you are at 30mph before you reach the baseball field, well outside of normal braking distance. On top of that, if you want to run a smooth train you have to slow before you reach the impedance box, in reality this just leads to slower operation. It's not 'better' driving, it forces ultra conservative operation which costs OTP. If the code points were 100% synced to braking distance, then maybe. As it stands they are set for the worst performing train which negates the advantages in agility the MU fleet has. Another thing to consider is that if the speed of the curve does not match what the ASC can present you automatically leads to an inefficiency, in a diesel most curves will code you to 38mph, even if its good for 50. So the system is not set on millimeter precision and you often have to go well underspeed to avoid being penalized by it. NYCT let this issue go too far. Hopefully PTC will be designed to avoid some of these issues.

DaveBarraza wrote:Agree that any hard braking could result in "passengers-off-balance." This is not unlike the current situation in Rule 410 territory which has existed on LIRR for some time, no? (possibly why the beers used to be served in a cup with a straw?!?)...

To address the point of 410, and the real detriment of blind driving is that the Train is driving the Engineer who becomes a passive participant in the safety of the equipment. In a lot of situations it is detrimental to the equipment to allow the brakes to apply in full service. In adverse conditions the wheels will lock up, or at the very least cause a slide. The fact that an Engineer cannot always anticipate a code drop and will get a harash application is what contributes to flat spots and fleet shortages.

In 410 straight run territory you have your time table and the signal at the last interlocking to give you an inkling of whether the ASC drop is a code drop, or train ahead based on that anticipated traffic.

With RAS there is no way to know if the 40 code is setting up a diverging route or if the block ahead is occupied, so you have to assume the worst and the Engineer, in an attempt to run a smooth train and not have constant severe braking (more flat spots) will hang back.
 #1501814  by BuddR32
 
fcqjx wrote:
BTW while on this topic I have 3 technical question about LIRR's ASC system: 1. Does LIRR use 100Hz or 91 2/3 Hz as the code carrier in Zone C? 2. In Zone A does Amtrak make use of any of the 250 Hz carrier codes from A interlocking east up to Harold, and if so, does LIRR receive and decode them? 3. Reading version 5.0 of LIRR's PTCIP (public, redacted version) A narrative section states that the ESA trackage will be using a 250 HZ system. Wondering just how this squares with the answer to the preceding questions.

LIRR uses the 100 HZ carrier in Zone C. ESA will be the 250 HZ carrier. Currently, the LI ASC equipment does NOT decode 250HZ
 #1501816  by Kelly&Kelly
 
Let us sort out some of the technical end of this speed control stuff:

Typically a railroad used DC track circuits for signalling. Consider that each rail is connected to one side of a 48 volt battery, with signal "blocks" being isolated from each other by insulated rail joints. At one end of each block is a battery, at the other end is an electromagnetic relay, or electric controlled switch that is activated by that battery. When a metal train axle shunts or bridges the two rails, it shorts out the battery causing the relay to de-energize or "drop". That relay is what activates the signal indications.

In third rail territory, both rails already contain one side of the 750 DC volt propulsion power, so to avoid its conflict, alternating current, instead of battery is used for signal "track" circuits. The LIRR uses 100 cycle AC for this. Where overhead AC catenary wires are installed, a different signal (track circuit) frequency is used in AC territory avoiding interference from that propulsion frequency.

The LIRR's speed control or cab signal system overlays another electric signal of different frequencies on the rails (or on wires between the rails) to activate the speed control system. Each cab signal indication or "aspect" is referenced from a different frequency. The magnetic current caused by this energy in the rails is "picked up" through induction by two "track receivers." which are wire coils under the engine's pilot. They are interpreted by the train's speed control system. Originally vibrating relays were used for this, now it's done electronically.

This system was designed by Westinghouse and installed after the 1950 wrecks through funding by the State of New York. When an engineman receives a cab signal indication (or speed indication) more restrictive than the speed at which he is operating, he receives a visible and audible warning. He must acknowledge the warning and reduce to the required speed. If he does not do this within a set time, the train stops automatically.

We hope this offers some insight into the conventional LIRR system for those who haven't worked with it. To those who have, excuse the simplification for the purpose of understanding.
 #1501908  by fcqjx
 
BuddR32 wrote:

LIRR uses the 100 HZ carrier in Zone C. ESA will be the 250 HZ carrier. Currently, the LI ASC equipment does NOT decode 250HZ
Thanks. Curious why this was chosen for ESA? Presumably Amtrak doesn't use any of the 250 based codes on the shared trackage.
 #1501946  by Backshophoss
 
Along with the Westbury wreck,WCBS reported LIRR has to replace all the ACSES gear installed due to it being outdated or recalled
by the manufacturer,so add this to the PTC delay.
Figure on Newsday to have a field day over this foul up! :(
 #1502557  by Head-end View
 
A LIRR employee friend of mine tells me the crews especially dislike the green-over-white "proceed" aspect of the RAS signals. With the green and white being so close together the aspect is hard to distinguish as you approach. I wondered about that too when I saw it. Most railroads separate any two lighted bulbs in a signal head for better visual clarity. :(