Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

why new signals on old line?

8017 views
40 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    July 2009
  • From: lavale, md
  • 4,638 posts
why new signals on old line?
Posted by gregc on Tuesday, June 24, 2014 10:49 AM

this morning i noticed a new signal bridge on I believe the old Lehigh Valley line in Manville, NJ heading west toward Phillipsburg.  They've done without signals on this line for probably close a century.   Why would they need to add light signals in this day of radios and other forms of communication?

greg - Philadelphia & Reading / Reading

  • Member since
    September 2003
  • 10,582 posts
Posted by mlehman on Tuesday, June 24, 2014 11:34 AM

Are they adding commuter rail, maybe?

Mike Lehman

Urbana, IL

  • Member since
    November 2002
  • From: US
  • 2,455 posts
Posted by wp8thsub on Tuesday, June 24, 2014 12:46 PM

There could be several reasons.  Maybe this line is being upgraded to comply with the positive train control rules http://en.wikipedia.org/wiki/Positive_train_control and signals are only part of the infrastructure improvements.

Even without PTC, radio communication isn't much of a safeguard.  Unsignalled trackage isn't necessarilly safer with radios than with phones or telegraph.

Signals wired on the Absolute Permissive Block principle provide a significant overlay of safety on a line otherwise dispatched using track warrants (or before that train orders and timetables).  Signals by themselves in such territory do not confer authority, existing solely to relay information about block occupancy.

If a line is slated for increased capacity, signaling allows for more trains to be operated with closer spacing, even without CTC.  Adding CTC (where the dispatcher remotely operates turnouts and signals at control points, and under which signals at such control points do confer authority instead of just occupancy) allows for greater capacity still.

See if this discussion addresses the line in question http://www.railroad.net/forums/viewtopic.php?f=127&t=94224&sid=fc2c4770cf3060f8c380dfc5a397a84c .

Rob Spangler

  • Member since
    June 2005
  • From: Phoenixville, PA
  • 3,495 posts
Posted by nbrodar on Thursday, June 26, 2014 11:10 PM

gregc

this morning i noticed a new signal bridge on I believe the old Lehigh Valley line in Manville, NJ heading west toward Phillipsburg.  They've done without signals on this line for probably close a century.   Why would they need to add light signals in this day of radios and other forms of communication?

 

Are you sure the line was non-signalled?  There has been a lot of work done up there, with tracks being realigned and signals moved.  Also adding signals to non-signalled track significately increases track capacity.

Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/

  • Member since
    October 2001
  • From: OH
  • 17,574 posts
Posted by BRAKIE on Friday, June 27, 2014 3:38 AM

PTC is a mandate from the FRA plus the continuing growth of rail shipments means the once low traffic track is being upgraded to handle more trains or the track is a faster shorter route.

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Friday, June 27, 2014 6:21 AM

PTC doesn't require signals, it requires a whole lot of communications and "signal" infrastructure, but it doesn't require an ABS or CTC sytem.  PTC is only being installed on lines that handle pasenger trains or a significant amount o RSSM type hazmat.  Lines that do onot meet that requirement will not have PTC.  PTC by itself doesn't increase capacity or train speeds, all it does is provide a layer of protection to stop a train that doesn't comply with a speed restriction or restrictive signal prior to it exceeding its authority.

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    October 2001
  • From: OH
  • 17,574 posts
Posted by BRAKIE on Friday, June 27, 2014 4:21 PM

dehusman

PTC doesn't require signals, it requires a whole lot of communications and "signal" infrastructure, but it doesn't require an ABS or CTC sytem.  PTC is only being installed on lines that handle pasenger trains or a significant amount o RSSM type hazmat.  Lines that do onot meet that requirement will not have PTC.  PTC by itself doesn't increase capacity or train speeds, all it does is provide a layer of protection to stop a train that doesn't comply with a speed restriction or restrictive signal prior to it exceeding its authority.

 

Dave,For basic knowledge.

http://www.fra.dot.gov/Page/P0358

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

  • Member since
    June 2005
  • From: Phoenixville, PA
  • 3,495 posts
Posted by nbrodar on Friday, June 27, 2014 7:34 PM

Which says exactly what Dave said.

Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/

  • Member since
    July 2009
  • From: lavale, md
  • 4,638 posts
Posted by gregc on Saturday, June 28, 2014 8:05 AM

It seems the PTC is a automatic and remotely operated system forcing a train to stop, or at least slow down, and is hardly surprising with the technology today.    Which seems to make adding optical signals even more puzzling.

Are optical signals only necessary on passenger lines?

greg - Philadelphia & Reading / Reading

  • Member since
    June 2005
  • From: Phoenixville, PA
  • 3,495 posts
Posted by nbrodar on Saturday, June 28, 2014 9:14 AM

PTC is horribly expensive, and still currently untried.  PTC requires a massive infrastructure both in lineside transponders and communications equipment, backroom computing power, and modifications to locomotives.  Optical signals while not cheap, are a proven technology and require no modifications to the rolling equipment.  Also PTC doesn't really protect shoving movements.  The person on the point of the movement still needs to able to see and read the lineside signals.

There are traffic lights on roads for a reason. Imagine you are driving your car with only your GPS telling when to stop and go - that's the grade school explanation of PTC. 

Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/

  • Member since
    July 2009
  • From: lavale, md
  • 4,638 posts
Posted by gregc on Saturday, June 28, 2014 10:37 AM

nbrodar
PTC is horribly expensive, and still currently untried.  PTC requires a massive infrastructure both in lineside transponders and communications equipment, backroom computing power, and modifications to locomotives.

you gotta start somewhere.   If this is where rail transportation expects to be in a decade or two, at least in heavy traffic areas, why continue to invest in older technology it will replace?

nbrodar
There are traffic lights on roads for a reason. Imagine you are driving your car with only your GPS telling when to stop and go - that's the grade school explanation of PTC.

not gps, fully autonomous ... google driveless cars

 

greg - Philadelphia & Reading / Reading

  • Member since
    August 2013
  • 118 posts
Posted by big daydreamer on Saturday, June 28, 2014 11:13 AM

gregc

Are optical signals only necessary on passenger lines?

no, not at all

Google's driverless car technology replaces the driver, not the road.  The car still has to look for and read traffic lights. http://youtu.be/YXylqtEQ0tk?t=6m36s

 

  • Member since
    July 2009
  • From: lavale, md
  • 4,638 posts
Posted by gregc on Saturday, June 28, 2014 12:29 PM

big daydreamer
Google's driverless car technology replaces the driver, not the road.  The car still has to look for and read traffic lights. http://youtube.com/YXylqtEQ0tk?t=6m36s

i didn't think PTC was replacing the train.

I assume  that it would have access to the same communication channel that remotely control light signals as well as any block detection that may indicate a train in front of it.

i think you much more complicated technology in your pocket (i.e. phone).

greg - Philadelphia & Reading / Reading

  • Member since
    October 2001
  • From: OH
  • 17,574 posts
Posted by BRAKIE on Saturday, June 28, 2014 5:01 PM

I know NS is going full bore on upgrading their signals for PTC  on the sandusky line and the majority of the old PRR signals has been removed from the Ft.Waye Line between Crestline and in Bucyrus,Ohio.

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

  • Member since
    June 2005
  • From: Phoenixville, PA
  • 3,495 posts
Posted by nbrodar on Saturday, June 28, 2014 10:09 PM

gregc

 I assume  that it would have access to the same communication channel that remotely control light signals as well as any block detection that may indicate a train in front of it.

i think you much more complicated technology in your pocket (i.e. phone).

 

 
Is it failsafe? Does it work 100% of the time, in 100% of the places?  Does it survive getting the crap beat out of it? Is the GPS recognition fine enough to translate not only what milepost you are at, but also what track you are on?
 
PTC is a tool for train management (and a pretty bad one in my opinion). Not an end all be all. 
 
PTC (as currently structured) cannot confir authority for a train to occupy a section of controlled track.  Only a dispatcher controlled signal or track warrant can.   PTC is an adjunct to these providing for the seperation of trains, not the actual authority for the movement of trains.

Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/

  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Monday, June 30, 2014 6:33 AM

gregc

It seems the PTC is a automatic and remotely operated system forcing a train to stop, or at least slow down, and is hardly surprising with the technology today.    Which seems to make adding optical signals even more puzzling.

Are optical signals only necessary on passenger lines?

 
PTC applies a penalty STOP on the train, it doesn't slow it down, it stops the train if the train does not or cannot comply with a restrictive condition.  It stops the train before it exceeds the authority.  Conventional cab signal and automatic train stop systems stop the train if it exceeds the authority, PTC stops the train before it exceeds the authority. 
 
The wayside signals are still needed to inform and give authority to the engineer so he can operate the train without hitting a penalty brake application.  Plus PTC is all about stop, there is nothing in PTC about go.  So the signals are need to tell the engineer when he can start or speed up.

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    March 2003
  • From: Central Iowa
  • 6,825 posts
Posted by jeffhergert on Monday, June 30, 2014 9:54 AM

In dark territory, PTC would enforce the end of authority, such as a track warrant, the same as a signal indication.  In dark territory, the "signal" to go is the issuance of more authority.  I think the Alaska Railroad is installing PTC on dark portions, as well as the signalled portions of their line.  

Eventually, some predict with future versions of PTC wayside signals will be removes.  All authority and routing, such as taking a siding at a meeting point, will be displayed on the onboard screen.  I think there are valid reasons to keep wayside signalling even then, but I'm not a bean-counter.

Jeff

 

  • Member since
    November 2013
  • From: Los Angeles
  • 283 posts
Posted by JOHN BRUCE III on Monday, June 30, 2014 11:58 AM

There are numerous situations PTC doesn't cover. Los Angeles Metrolink had two major accidents that led to the requirement for PTC: a head-on where an engineer was texting instead of watching signals, and a rear-end where the BNSF engineer may have fallen asleep. However, LA Metrolink has had just as many horrific accidents where a driver went around lowered crossing gates and derailed a cab car, which in one case was quickly hit by an oncoming train on the track where it had been deflected in the derailment. PTC would not have prevented either the driver running around the gates or the train hitting the derailed cab car, since that happened before any signal could have stopped the train.

So there are still numerous cases, illustrated by fairly recent fatal accidents, where PTC would not help. I believe the accident at Drawbridge, NJ, where a slightly misaligned drawbridge derailed an Amtrak train, would not have been prevented by PTC, since signals were apparently not affected. The massively fatal accident to a German ICE train caused by a WHEEL that broke under the train would not have been prevented by PTC. Any mudslide, rockslide, errant vehicle or debris on the track, broken rail, misalignmnent,washout, etc that either does not activate signals, or takes place too soon for the train to stop, will not be prevented by PTC.

Thi leads to the puzzling situation that, even though LA Metrolink will be an early adopter of PTC, and has replaced its cab cars with new ones that have elevated cabs and crash-resistant noses, those cab cars now also have most of their forward seats removed, since PTC still won't keep the passengers in those cab cars safe enough to ride in them!

 

My blog: http://modelrrmisc.blogspot.com/
  • Member since
    October 2001
  • From: OH
  • 17,574 posts
Posted by BRAKIE on Monday, June 30, 2014 11:58 AM

dehusman
The wayside signals are still needed to inform and give authority to the engineer so he can operate the train without hitting a penalty brake application. Plus PTC is all about stop, there is nothing in PTC about go. So the signals are need to tell the engineer when he can start or speed up.

Absolutely! As I already mention NS is spending millions of dollars upgrading signals to PTC standards..

As you mention PTC will stop the train if the engineer disobeys a signal.

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Monday, June 30, 2014 1:35 PM

BRAKIE
As you mention PTC will stop the train if the engineer disobeys a signal.
 

 
It goes beyond that.  PTC stops a train if it thinks the engineer ins't going to be able to comply with it.  A train has passed an approach signal, it the engineer doesn't reduce speed to 30 mph/40 passenger (or appropriate speed) the system will have a penalty application.  If the train is approaching a stop signal and the PTC system, knowing the speed of the train, the weight of the train, the location of the train, the location of the signal, will calculate the point at which action has to be taken to stop the train prior to passing the stop signal, if the engineer is operating a train at a speed which will not permit the train to stop prior to passing the signal, the system will initiate a penalty application.
 
A train is going down the railroad, and passes the approach signal, slows to 28 mph and holds that.  PTC figures that it takes 2500 ft to stop that particular train from 28 mph.  If the engineer hasn't started slowing the train prior to 2500 ft before the signal, PTC will apply a penalty application, even though the train hasn't passed a stop signal.
 
PTC also will not stop low speed collisions and exceeding authority.

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    November 2013
  • From: Los Angeles
  • 283 posts
Posted by JOHN BRUCE III on Monday, June 30, 2014 1:57 PM

Regarding the 1996 accident at Drawbridge, NJ, I found this:

 

"

In a dramatic news conference at the Gateway Hilton in Newark, officials of the National Transportation Safety Board indicated they had found crucial evidence on the second day of their investigation that appeared to explain not only the cause of the derailment, but also why there had been no red signals that might have halted the train and prevented the wreck.

"They said that while the displaced rails resembled a small upward ramp, with the end of one five inches above the other, the rails were still touching so that electrical contact was not broken and a red signal that would have halted the oncoming train was never posted."

My blog: http://modelrrmisc.blogspot.com/
  • Member since
    September 2003
  • 10,582 posts
Posted by mlehman on Monday, June 30, 2014 2:14 PM

No system is completely failsafe. That's why there are not only signals, but a rule book to govern interpretation of the signals and a human to apply the rules to what they see. I also don't see the logic in blaming the signal system for track defects and failure of a human to comply. It's not designed to deal with those issues.

There are long stretches of unsignaled track where PTC would improve safety without question. On signaled track, it provides redundancy. Presuming the bugs get worked out, it will be an important factor in once again significantly improving RR safety. It's unfortunate, but true that some of the most important safety initiatives in RRing were forced on management by law. Such a system is technically feasible.

And the cost of human life is incalcuable. You can never pay enough to account for someone's life, even though the courts make such determinations regularly.

Mike Lehman

Urbana, IL

  • Member since
    November 2013
  • From: Los Angeles
  • 283 posts
Posted by JOHN BRUCE III on Monday, June 30, 2014 4:46 PM

I hink there are two questions. One is whether it's technologically feasible: the AAR's official position is "PTC is an unprecedented challenge from both a technical and operational perspective. A properly functioning PTC system must be able to determine the precise location, direction and speed of trains; warn train operators of potential problems; and take immediate action if the operator does not respond to the warning provided by the PTC system. A fully functioning PTC system must also allow for communication between all passenger, commuter and freight rail systems traveling on PTC-equipped track. There is currently no commercially available system that meets these requirements therefore much of the required technology and engineering applications are being developed from scratch. . . .

"However, far too many technological and regulatory barriers exist today, and despite the railroad industry’s best efforts, the 2015 deadline for full implementation of PTC mandated by Congress will not be met."
 
In other words, it will not be done on time, and there is still some question about its feasibility.
 
The second question is how much money do you want to spend to completely eliminate risk? We agree that PTC will not stop grade crossing incidents, nor low speed collisions, nor vaious stuff-happens conditions. You may say that you can never pay enough to eliminate risk -- but you can't eliminate all risk. The 2008 head-on at LA Metrolink that was the impetus for PTC was caused by management not applying existing policies -- the engineer wasn't calling signals to the conductor; the conductor was part of a get-along attitude among crews. Management tolerated this. If people had been doing their jobs according to existing policy, it wouldn't have happened.
 
How much of other people's money do you want to spend to solve problems that might have far less expensive solutions?
My blog: http://modelrrmisc.blogspot.com/
  • Member since
    September 2003
  • 10,582 posts
Posted by mlehman on Monday, June 30, 2014 5:25 PM

JOHN BRUCE III
The second question is how much money do you want to spend to completely eliminate risk?

I don't think anyone is asserting that PTC will "completely eliminate risk."  So the cost of THAT system is pretty irrelevant, although I'm certain it's high.

The price of PTC is relevant. Got a number? I suspect it's pretty big, but not something that prevents the RRs from moving forward. It's mgmt's priorities.

2015 isn't too far off, but I'm certain that if it's not ready for primetime, the government's not going to insist on anyone wusing a life-safety ssystem before it's viable. In the meantime, companies should be working toward the deadline as best possible, so if there is a delay, it will be minimal. Areas of track where PTC is in operation should be put to use verifying system compliance.

Stalling on safety is just a bad idea. Besides, money and labor are likely as cheap as they'll ever be. Most RRs are doing fine and most commercial lenders see them as good risks if borrowing is needed. Why put this off, any longer.

Mike Lehman

Urbana, IL

  • Member since
    July 2009
  • From: lavale, md
  • 4,638 posts
Posted by gregc on Monday, June 30, 2014 7:58 PM

JOHN BRUCE III
I think there are two questions. One is whether it's technologically feasible

I don't believe the technology is terribly complicated compared to other systems.    If it were available today, it would be in use, so of course it needs to be developed, but I doubt entirely from scratch.

I think it's less complicated than the air traffic control system and automated systems within aircraft.    Consider the number of fast moving aircraft in a crowded area like New York with three major airports and safely doing it in all types of weather.

It looks like it is mostly communications technology that railroads have plenty of experience with and data management.    However, they have a lot of track miles to potentially upgrade.

JOHN BRUCE III
The second question is how much money do you want to spend to completely eliminate risk?
 
I doubt PTC expected to completely eliminate risk/accidents?   And despite the mandate, what is a reasonable amount of time to develop and how many track miles are covered in what timeframe?     Like all technology, it will be replaced with better and less expensive technology  over time.
 
One simple way of evaluating cost is to compare it to the potential savings.   How many accidents will it prevent, damage to equipment and material being shipped, cost of repairing trackage to restore service, as well as harm to people?
 
how much has the current signaling system cost since its genesis in the early 1830s(?) ?   How many accidents has it prevented and money saved, as well as safely increasing capacity?
 
PTC seems inevitable and doable.

greg - Philadelphia & Reading / Reading

  • Member since
    October 2001
  • From: OH
  • 17,574 posts
Posted by BRAKIE on Wednesday, July 2, 2014 5:56 AM

JOHN BRUCE III
How much of other people's money do you want to spend to solve problems that might have far less expensive solutions?

What price life?

If a train carrying hazmat can be stopped before ramming another train that will save millions in property and environmental damages and maybe lives of the crew and civilians which if killed in the wreck and the aftermath will result in more millions in wrongful death lawsuit settlements.

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Wednesday, July 2, 2014 7:01 AM

BRAKIE
 If a train carrying hazmat can be stopped before ramming another train that will save millions in property and environmental damages and maybe lives of the crew and civilians which if killed in the wreck and the aftermath will result in more millions in wrongful death lawsuit settlements. 

First off, despite all the hype on the news and in these forums, collisions at speed, major derailments and hazardous material releases that are a major risk are actually pretty few and far between.  PTC will help eliminate the major risks caused primarily by human error involving main track authority and signal compliance.  It probably wouldn't have prevented Lac Megantic (the engines were shut down), or the BNSF derailment in ND (another train derailed into the path of the oil train) or the derailment and fire in Kentucky (track/weather caused) or the derailment on the bridge in Phillie (track caused).   I am having a hard time coming up with a recent oil train derailment that PTC would have prevented.

PTC is alson NOT being installed on all routes, maybe a third of the main track mileage, only the track that carries passenger trains or a certain amount of the really serious hazmat (which does not include crude oil).

It will prevent a whole bunch of potential catastrophes and crew decertifications.  It will prevent a lot of opportunities for failure (the vast majority of which do not result in a collision, fatality, derailment or hazmat release now).  That is a good thing.  Is it worth the cost?  Time will tell.

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    October 2001
  • From: OH
  • 17,574 posts
Posted by BRAKIE on Wednesday, July 2, 2014 7:38 AM

dehusman
PTC is alson NOT being installed on all routes, maybe a third of the main track mileage, only the track that carries passenger trains or a certain amount of the really serious hazmat (which does not include crude oil).

Well,like I said NS is going full blast installing PTC on the Sandusky lines and lines South of Columbus.

The FRA mandate for PTC was Dec 31, 2015 now its Dec 31,2020.

Here's a interesting read on the subject.

http://www.railwayage.com/index.php/ptc/fra-says-ptc-deadline-wont-be-met.html

 

 

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

  • Member since
    November 2013
  • From: Los Angeles
  • 283 posts
Posted by JOHN BRUCE III on Wednesday, July 2, 2014 10:06 AM

dehusman
 

It will prevent a whole bunch of. . . crew decertifications.  It will prevent a lot of opportunities for failure (the vast majority of which do not result in a collision, fatality, derailment or hazmat release now).  That is a good thing.  Is it worth the cost?  Time will tell.

 

 

I think Mr Husman is getting to the heart of things here.  Human error involving main track authority and signal compliance, as he puts it, is covered by rules well over 100 years old. The fatal accidents that PTC could have prevented resulted, let's face it, from intoxicated crews, crews violating existing rules against personal cell phone use, conductors and supervisors refusing to enforce existing rules, etc. I would guess that a PTC-forced stop would decertify an individual engineer -- but it would probably save the job of the official who hadn't been supervising the engineer in the first place. In effect, one view of the project is that it will save the jobs of incompetent mid level officials. What's that worth?

My blog: http://modelrrmisc.blogspot.com/
  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Wednesday, July 2, 2014 10:47 AM

JOHN BRUCE III
  The fatal accidents that PTC could have prevented resulted, let's face it, from intoxicated crews, crews violating existing rules against personal cell phone use, conductors and supervisors refusing to enforce existing rules, etc. I would guess that a PTC-forced stop would decertify an individual engineer --

An engineer is decertified for violating the rule.  PTC prevents violating the rule.  A PTC penalty application isn't necessarily a decertifiable event since the rule wasn't violated.

Dave H. Painted side goes up. My website : wnbranch.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

There are no community member online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!