The way PTC is being installled is willfull derilection of duty

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The way PTC is being installled is willfull derilection of duty
Posted by daveklepper on Monday, February 12, 2018 10:11 AM

Fatel wrecks need Not Continue until Positive Train Control is implemented.

Common to Frankfort Junction and this latest Amtrak CSX tragedy is the de-activation of an existing system for safety to permit straight-forward installation of PTC,  In the case of Frankfort Junciton curve, the old PRR cab-signal and warning and braking automatic system Did provide for safety for Permanent speed restrictions.  I saw this in operation by several rides on the fron platforms of MP-54 trains, and I assure you that if the system on that track had still been in operaton, the tragedy would have been prevented.  In this second case the safety of a signal system that would have given the engineer notice that the switch was not aligned properly was deactivated and he took the verbal and possibly writen auathorization from the dispatcher that the switch was properly aligned.

Ladies and gentlemen, this is not rocket science.  We don't need to duplicate a human brain in transistors.  Some method must be found NOW to permit PTC to be installed while existing safety systems Continue to Operate.   Anything else is a derilection of duty.

If not, the alternative would be not to operate any Amtrak train over dark territory.  Use a bus shuttle or rerrout.  The Silver Star could have been rerouted on the A-line with bus connecitons or just temporary loss of service to the bypassed stations.

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Posted by VOLKER LANDWEHR on Monday, February 12, 2018 4:46 PM

I think the promlem is that the railroads designed PTC as an overlay to the existing signal system. It depends on its functions. To connect the two you have to shut down the signals.

BN once designed ACSES as a stand-alone kind of PTC.

Track circuits are the best way to detect broken rails as required in 49 CFR 236.1005 (5)

Another paragraph of this is the reason given by the railroads for the overlay design:

§ 236.1007 Additional requirements for high-speed service.
(a) A
PTC railroad that conducts a passenger operation at or greater than 60 miles per hour or a freight operation at or greater than 50 miles per hour shall have installed a PTC system including or working in concert with technology that includes all of the safety-critical functional attributes of a block signal system meeting the requirements of this part, including appropriate fouling circuits and broken rail detection (or equivalent safeguards).
If this requirement really demanded for an overlay system or if a stand-alone with logic interconnection would have been possible I don't know. But even the temporary shut-down would have been necessary.
Regards, Volker
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Posted by BaltACD on Monday, February 12, 2018 5:06 PM

PTC is not a stand alone system - it relies on the the existing signal systems (where signals are used).  Those signal systems are currently running on signals and relay cases that in some cases have been in service for approaching 90 years (having been installed in the 20's and 30's).  I suspect the carriers installing PTC in signalled territory felt it was to their benefit to replace the antiquated signals and relays with current 'state of the art' equipment since maintaining the antiquated equipment was a real 'adventure in babysitting', full of 'kluges' to make up for parts that could no longer be obtained. 

Whenever you are changing existing signal equipment you are at risk until the new equipment is installed, tested and operating reliably.  Totally shutting down operations in not a viable option.

PTC is being installed on DARK terrirories and all switches have had to be fitted with equipment to transmit their switch positions.  Before my retirement it was installed on CSX's Ohio River subdivision between Parkersburg and Huntington - it was in 'test' operation when I pulled the pin.  There were issues in getting it to perform as intended, but I was not privy to the specifics.

To install Dark PTC on a Signaled PTC route would require significant additional investment and in the paraphanalia necessary to record and transmit the position of every Main Track switch as the Signal System when in operation already performs that function.

         

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Posted by Randy Stahl on Monday, February 12, 2018 6:12 PM

VOLKER LANDWEHR

I think the promlem is that the railroads designed PTC as an overlay to the existing signal system. It depends on its functions. To connect the two you have to shut down the signals.

BN once designed ACSES as a stand-alone kind of PTC.

Track circuits are the best way to detect broken rails as required in 49 CFR 236.1005 (5)

Another paragraph of this is the reason given by the railroads for the overlay design:

§ 236.1007 Additional requirements for high-speed service.
(a) A
PTC railroad that conducts a passenger operation at or greater than 60 miles per hour or a freight operation at or greater than 50 miles per hour shall have installed a PTC system including or working in concert with technology that includes all of the safety-critical functional attributes of a block signal system meeting the requirements of this part, including appropriate fouling circuits and broken rail detection (or equivalent safeguards).
If this requirement really demanded for an overlay system or if a stand-alone with logic interconnection would have been possible I don't know. But even the temporary shut-down would have been necessary.
Regards, Volker
 

ACSES = Amtrak civil speed enforcement system. Not BN.

ACSES is an overlay to ATC.

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Posted by n012944 on Monday, February 12, 2018 8:10 PM

daveklepper
 Anything else is a derilection of duty.

If not, the alternative would be not to operate any Amtrak train over dark territory.  Use a bus shuttle or rerrout.  The Silver Star could have been rerouted on the A-line with bus connecitons or just temporary loss of service to the bypassed stations.

 

 
Oh please.  Amtrak runs in dark territory every day, and does just fine.  To make such a broad statment over one tragic incident is ridiculous.

 

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Posted by daveklepper on Tuesday, February 13, 2018 2:26 AM

Correction.   Amtrak running in dark territory every day is not a problem, because the specific tasks of each individual involved are known and practised repeatedly.  I am Only referring the changeover from existing safety systems of every type to PTC.

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Posted by VOLKER LANDWEHR on Tuesday, February 13, 2018 2:59 AM

Randy Stahl
ACSES = Amtrak civil speed enforcement system. Not BN. ACSES is an overlay to ATC.

Thank you for the correction.

I meant BN and ARES. I should have looked it up again. Memory sometimes doesn't serve well.
Regards, Volker

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Posted by daveklepper on Tuesday, February 13, 2018 8:43 AM

Also, No1, in addition to the routine nature of the procedures in the dark territory where Amtrak runs every day, the rail traffic is far less.

An it is not one incident that prompted by comment, but at least two.

And there does seem to be a kind of jinx associated with this sort of tragedy.  The grade-time signal system for the Brighton line had already been designed at the time of the terrible Malbone Street wreck in Brooklyn.  ABS was being installed at the time of the Southern Railroad's head-on between two fast passenger trains.

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Posted by n012944 on Tuesday, February 13, 2018 3:32 PM

daveklepper

Correction.   Amtrak running in dark territory every day is not a problem, because the specific tasks of each individual involved are known and practised repeatedly. 

 

So is restoring a mainline switch.....

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Posted by oltmannd on Tuesday, February 13, 2018 3:44 PM

Randy Stahl

 

 
VOLKER LANDWEHR

I think the promlem is that the railroads designed PTC as an overlay to the existing signal system. It depends on its functions. To connect the two you have to shut down the signals.

BN once designed ACSES as a stand-alone kind of PTC.

Track circuits are the best way to detect broken rails as required in 49 CFR 236.1005 (5)

Another paragraph of this is the reason given by the railroads for the overlay design:

§ 236.1007 Additional requirements for high-speed service.
(a) A
PTC railroad that conducts a passenger operation at or greater than 60 miles per hour or a freight operation at or greater than 50 miles per hour shall have installed a PTC system including or working in concert with technology that includes all of the safety-critical functional attributes of a block signal system meeting the requirements of this part, including appropriate fouling circuits and broken rail detection (or equivalent safeguards).
If this requirement really demanded for an overlay system or if a stand-alone with logic interconnection would have been possible I don't know. But even the temporary shut-down would have been necessary.
Regards, Volker
 

 

 

ACSES = Amtrak civil speed enforcement system. Not BN.

ACSES is an overlay to ATC.

 

BN's system was ARES.  An early, proprietary offshoot by Rockwell Collins of the ATCS system being spec'd out by the AAR.  ATCS was the progenitor of the I-ETMS system being installed to satisfy the PTC regs.

-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/

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Posted by oltmannd on Tuesday, February 13, 2018 3:49 PM

BaltACD
PTC is not a stand alone system - it relies on the the existing signal systems (where signals are used).

This is a very important point.  The regs REQUIRE PTC to enforce existing signal system indications, as they exist.  

If the industry and/or gov't had allowed for organic growth of PTC - and gotten a much earlier start on this - we could have would up much simpler system, with less parts, higher capacity and more reliability.  Now, we have to work backwards toward that goal.

-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/

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Posted by Euclid on Tuesday, February 13, 2018 4:02 PM

oltmannd
If the industry and/or gov't had allowed for organic growth of PTC - and gotten a much earlier start on this - we could have would up much simpler system, with less parts, higher capacity and more reliability.  Now, we have to work backwards toward that goal.

Aside from the issue of how early the start was; what reasons were there for not choosing organic growth of PTC? From what you say, it sounds like it would have been the best choise.

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Posted by Shadow the Cats owner on Tuesday, February 13, 2018 4:05 PM

The way I am looking at PTC is the way I am looking at ELD's especially after this latest accident in SC.  The Government in it's infinate wisdom to force companies to spend money in order to comply with regulations came up with a doosy for the RR industry that is costing Billions to devolp the Government is not helping to devolp and they want full compliance by such a date.  

 

We had the same problem here in the OTR industry and it took livestock haulers saying fine where do you want the cattle offload spots from when we go dead on the law built when we can not meet delivery schedules due to weather or traffic or loading delays built.  The FMCSA said impossible that will not happen.  So 3 larger bull hauling companies run by respected fleet leasing carriers such as RUAN my husbands cousin was one of the RUAN staff involved in this study riding along to prove it could not make the delivery times for trucks even 300 miles away with ELD's on livestock hauling trucks.  FMCSA granted a waiver to that part of the industry. Sometimes a feel good regulation or one size fits all does not work in the real world when it comes down to it.  PTC is going to be a pain in the butt until it is fully installed then the first time an accident happens that could NOT have been prevented even with it installed look for more hand wringing and demand it be installed there also.

 

 

Anyone notice how produce is climbing in price at the stores since the middle of December.  Well I can tell you why.  Carriers are demanding Detention time from both Shippers and Receivers on that side of the industry.  Why because they can track how long it takes to load up the truck and unload it.  I can tell you this the big shots in the produce industry are madder than a hornets nest that got kicked.  Why they are now having to pay 200-300 bucks and hour after 2 for those trucks that used to wait for free for them to harvest the crops out of the field and then process and cool it.  I have a close friend that owns a smaller carrier that hauls produce into Jewel Foods.  Right now he has 20 Grand in Detention time in billing waiting to be collected and he has every bit documented to the point they can not contest it.  KLLM Marten Prime have millions in Detention time billed to shippers and receivers nationwide.  Carriers have the upper hand and are using it to get their customers to stop holding their trucks hostage for hours.  

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Posted by BaltACD on Tuesday, February 13, 2018 4:42 PM

Shadow the Cats owner
Anyone notice how produce is climbing in price at the stores since the middle of December.  Well I can tell you why.  Carriers are demanding Detention time from both Shippers and Receivers on that side of the industry.  Why because they can track how long it takes to load up the truck and unload it.  I can tell you this the big shots in the produce industry are madder than a hornets nest that got kicked.  Why they are now having to pay 200-300 bucks and hour after 2 for those trucks that used to wait for free for them to harvest the crops out of the field and then process and cool it.  I have a close friend that owns a smaller carrier that hauls produce into Jewel Foods.  Right now he has 20 Grand in Detention time in billing waiting to be collected and he has every bit documented to the point they can not contest it.  KLLM Marten Prime have millions in Detention time billed to shippers and receivers nationwide.  Carriers have the upper hand and are using it to get their customers to stop holding their trucks hostage for hours.  

Reason the producers are screaming goes beyond just the money - it points out with an inflamed thumb that the producers loading process is incompetent.  ELD's highlight that fact with chargeable proof. 

In railroad billing, there would be more hell raised over demurrage and detention charges than ever cropped up in contesting freight bills.  Freight bills are freight bills.  Demurrage and Detention Charges are a result of the individual plants traffic manager not accomplishing his job of getting cars loaded and/or unloaded and released back to the railroad so a not to incure the charges in the first place.

         

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Posted by VOLKER LANDWEHR on Tuesday, February 13, 2018 5:32 PM

oltmannd
This is a very important point. The regs REQUIRE PTC to enforce existing signal system indications, as they exist.

Is this really the case? Here is the wording of the according paragraph as already posted above (bold emphasis by me):

§ 236.1007 Additional requirements for high-speed service.
(a) A
PTC railroad that conducts a passenger operation at or greater than 60 miles per hour or a freight operation at or greater than 50 miles per hour shall have installed a PTC system including or working in concert with technology that includes all of the safety-critical functional attributes of a block signal system meeting the requirements of this part, including appropriate fouling circuits and broken rail detection (or equivalent safeguards).
 
The text allows two alternatives, including or working in concert. As I understand it, the railroads choose including. But what would have "working in concert" meant, perhaps a stand-alone PTC with logic interconnection to the existing signaling system?
Regards, Volker
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Posted by BaltACD on Tuesday, February 13, 2018 5:52 PM

VOLKER LANDWEHR
 
oltmannd
This is a very important point. The regs REQUIRE PTC to enforce existing signal system indications, as they exist. 

Is this really the case? Here is the wording of the according paragraph as already posted above (bold emphasis by me):

§ 236.1007 Additional requirements for high-speed service.
(a) A
PTC railroad that conducts a passenger operation at or greater than 60 miles per hour or a freight operation at or greater than 50 miles per hour shall have installed a PTC system including or working in concert with technology that includes all of the safety-critical functional attributes of a block signal system meeting the requirements of this part, including appropriate fouling circuits and broken rail detection (or equivalent safeguards).
 
The text allows two alternatives, including or working in concert. As I understand it, the railroads choose including. But what would have "working in concert" meant, perhaps a stand-alone PTC with logic interconnection to the existing signaling system?
Regards, Volker

My practical understanding of 'including or working in concert' are two ways of saying the same thing and thus giving lawyers something to argue about in the law suits that will result when an accident is pinned on PTC failure.

         

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Posted by Overmod on Tuesday, February 13, 2018 5:55 PM

This is an interesting question, and the interesting interpretation for me is less concerning your highlighted words than the definition immediately following:

§ 236.1007
with technology that includes all of the safety-critical functional attributes of a block signal system meeting the requirements of this part...

If the technology actually involves block-signal equipment, then 'including' and 'working in concert with' are really similar in requiring full interfacing with equipment that has been adapted (for example by providing one-bulb one-aspect heads throughout) for that purpose.

But if we discuss equipment that provides the 'safety-critical functional attributes' of a block-signal system, we promptly see that almost any CBTC system can meet the functional attributes of any fixed-block system, as long as it has subsystems capable of providing the default requirements of part 236, subpart I (in part 236.1005(c) et seq.) with particular respect to detecting damage to track continuity (which I believe relatively few 'modern' CBTC instantiations inherently provide).

It will have occurred to you that the PTC 'mandate' involves at least four core functionalities that are not well-served by any one physical system, and hence that "PTC" itself is best provided by a coordinated software approach running across different physical systems -- one of which would likely include the pre-existing portions of an ABS installation that provide its track sensing and power, since there is a recognizable benefit in time and cost to re-using as much of that infrastructure as possible.  Whether or not a given road would then expend many megadollars more to overlay this system with still further CBTC, including electrical track-circuit backup for the critical parts of the communication protocols used for that CBTC, seems relatively unlikely to me, even though there are potentially much higher benefits from that than from the current kludge.

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Posted by blue streak 1 on Tuesday, February 13, 2018 7:05 PM

Amtrak on their portion of the NEC chose ACSES overlay to their ATC that is more expensive.  However that choice may have many benefits that the other systems seem to lack.

Do we need to wonder if some RRs are expecting this year's mandate to be extended or cancelled by executive action ?   

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Posted by BaltACD on Tuesday, February 13, 2018 7:17 PM

blue streak 1
Amtrak on their portion of the NEC chose ACSES overlay to their ATC that is more expensive.  However that choice may have many benefits that the other systems seem to lack.

Do we need to wonder if some RRs are expecting this year's mandate to be extended or cancelled by executive action ? 

The ARR within the past week or so has stated the the Class 1 carriers all expect to be PTC compliant by 12/31/18.

The various governmental commuter agencies appear to the ones that are in line to fail to meet the 12/31 requirement and will beg for an extension until 2020.

I think I saw in yesterday's new that Sun Rail just signed a contract for design, build and install on their system within the past week.  With that being the case the 12/31 date, to me, seem impossible.

https://www.railwayage.com/cs/sunrail-selects-wabtec-ptc/

         

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Posted by zardoz on Tuesday, February 13, 2018 9:06 PM

Overmod

....It will have occurred to you that the PTC 'mandate' involves at least four core functionalities that are not well-served by any one physical system, and hence that "PTC" itself is best provided by a coordinated software approach running across different physical systems....

I am amazed, but not surprised, at what a fupped duck boonedoggle this whole PTC mess is. 

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Posted by aegrotatio on Tuesday, February 13, 2018 9:54 PM

BaltACD

Whenever you are changing existing signal equipment you are at risk until the new equipment is installed, tested and operating reliably.  Totally shutting down operations in not a viable option.

 

This is precisely how WMATA murdered nine and injured 80 in 2009.  Not only was there a risk, they were routinely replacing wayside equipment that was not fully compatible with the track systems and vice-versa to save time and increase operational availability.

 

Even when controllers observed "bobbing" signals and "ghost trains" for many months, nobody took any steps.  It took the deaths of nine people to force steps to be taken.

 

Almost ten years later, our perfectly good automatic train control system is still shut down due to maintenance stupidity and incorrect corrective measures taken by operations.

 

 

 

 

 

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Posted by daveklepper on Tuesday, February 13, 2018 10:38 PM

n012944

 I agree.  Did whoever reported to the Dispatcher that the switch was restored actually do the restoration?  Did he or she personally check physically to see the switch restored?  Is there any assurance that someone with a switch key that wished to perform sabatogue (very unlikely, but a lawyer can bring up the possibility) did not lock the switch in the reverse position after the switch was restored?

Going dark on a heavily-traveled rout that usually has signal protection would seem to require a bit more attention to safety than on a regularly dark rout.  Am I mistaken in this?

Also, I am still unhappy that the Brotherhood did not regester a complaint to the Feds when HH removed 3-point protection.  Perhaps that could have been the beginning of a lessening of Safety-First culture at CSX that indirectly could lead to a disaster like the most recent we are discussing?  I am asking this as a question.  And what is the status of 3-point protection on CSX today?

 
daveklepper

Correction.   Amtrak running in dark territory every day is not a problem, because the specific tasks of each individual involved are known and practised repeatedly. 

 

 

 

So is restoring a mainline switch.....

 

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Posted by daveklepper on Wednesday, February 14, 2018 12:10 AM

What would be the safety equivalent of three-point train-being worked-on protection for switch locking safety?  Here might be a possible suggestion, based on what I observed on the B&M some 65 years ago, but adapted to a two-man crew:   This applies to the specific situation of the train backed into the siding and awaiting a meet with a train passing by on the main line in either diretion.  After securing the train, both crew members exit the cab.  The switch is restored and locked and reported to the dispatcher.  One crew member remains stationed on each side of the track and performs a roll-by inspection of the passing train.  If the wait is longer than a specific time, the crew can wait in the cab but must return to perform the ground level roll-by some five minutes or more before the passing train arrivves.  After it clears, the switch is reset for the siding, one reboards the cab, the other remains behind to restore the switch.  After that train is entirely on the main, and the switch is restored, the train can slowly back down on the main to pick up the crewman to avoid his having to walk the length of the consist, since the train that past gives some assurance of a cear track.  If the weather is too horrible for this procedure, with health being an issure, then additional speed restridtions may be in order.

Your critiques will be of interest.

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Posted by VOLKER LANDWEHR on Wednesday, February 14, 2018 3:41 AM

BaltACD
My practical understanding of 'including or working in concert' are two ways of saying the same thing and thus giving lawyers something to argue about in the law suits that will result when an accident is pinned on PTC failure.

My experience with standards show that the word or indicates a different approach. But I have to admit that my experience is limited to European standards. That is the reason for asking. And European standards are not put in laws.

I remember an editorial in RailwayAge: https://www.railwayage.com/cs/the-tangled-tale-of-ptc/?RAchannel=home

and Wick Moormans rebuttal: https://www.railwayage.com/regulatory/untangling-the-tale-of-ptc/?RAchannel=home

I couldn't believe that the experts had overlooked the requirement to implement the signal system. So I looked for the wording. Since I found it, I'm not sure how to understand Wick Moorman's answer, an explanation or an excuse, naturally from my European viewpoint.
Regards, Volker

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Posted by VOLKER LANDWEHR on Wednesday, February 14, 2018 4:14 AM

Overmod
If the technology actually involves block-signal equipment, then 'including' and 'working in concert with' are really similar in requiring full interfacing with equipment that has been adapted (for example by providing one-bulb one-aspect heads throughout) for that purpose.

I believe including or working in concert with open different ways to same goal, having the signaling system as an additional safety feature. As fall-back system?

The railroads made dependend on the signaling system (including). The other way is to have stand-alone system that interconnects with the signaling system, by comparing the different system's indications and decide what to allow.

Overmod
It will have occurred to you that the PTC 'mandate' involves at least four core functionalities that are not well-served by any one physical system, and hence that "PTC" itself is best provided by a coordinated software approach running across different physical systems -- one of which would likely include the pre-existing portions of an ABS installation that provide its track sensing and power, since there is a recognizable benefit in time and cost to re-using as much of that infrastructure as possible.

Sure, that was the reason why PTC was mandated. But PTC could handle it alone without the implementation of the signaling system. For some necessary detections it would be the easiest way to keep the track circuits. 

The stand-alone would have saved the costs for a lot new signals und it would have allowed business benefits that the implemented system doesn't allow.

I think the decision was made because the design of the implemented system seemed easier and faster to accomplish considering the dead line not because of §236.1007 (a) requirements.
Regards, Volker

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Posted by VOLKER LANDWEHR on Wednesday, February 14, 2018 9:24 AM

I have looked for information about CBCT and found this website:
https://www.fra.dot.gov/Page/P0358

The FRA definition from this site:
CBTC (Communications-Based Train Control): A vital stand-alone Positive Train Control (PTC) system, as defined in 49 Code of Federal Regulations (CFR) Part 236, Subpart I, Section 236.1015(e)(3). CBTC replaces the existing traffic control method of operation by requesting an override of the wayside signal system to display a Flashing Green or Flashing Yellow (if the green aspect does not illuminate) signal aspect. (Type Approved and Certified by FRA.)

And the referenced law:
§ 236.1015 PTC Safety Plan content requirements and PTC System Certification.
(e) The following additional requirements apply to:

(3)Stand-alone. A PTC system proposed on a newly constructed track, an existing track for which no signal system exists, as a replacement for an existing signal or train control system, or otherwise to replace or materially modify the existing method of operation, shall:

(i) Reliably execute the functions required by § 236.1005 and be demonstrated to do so to FRA's satisfaction; and

(ii) Have a PTCSP establishing, with a high degree of confidence, that the system will not introduce new hazards that have not been mitigated. The supporting risk assessment shall evaluate all intended changes in railroad operations in relation to the introduction of the new system and shall examine in detail the direct and indirect effects of all changes in the method of operations.

If I read all this correctly there was a different approach than the overlay possible and got certified by the FRA.
Regards, Volker

 

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Posted by Overmod on Wednesday, February 14, 2018 9:50 AM

Just when the discussion gets good I wind up out in the field on a phone that only shows two lines of text.

The two phrases separated by 'or' do have distinct meanings (even without applying Talmudic logic); they blur somewhat because the underlying assumption is that all PTC must take full cognizance of things most easily implemented with physical, robust track circuits, including the items in 1005 and elsewhere in the relevant sections that are partially cited in 1007.

 

Had the block-location logic of PTC been implemented modularly separate from the track-circuit-detection part, it would be relatively easy to 'harmonize' (as the ITU would say) CBTC with open-switch and broken-rail detection, etc.  Instead we get the current 'overlay' paradigm taking the most limiting assumptions behind ABS and forcing them onto what should be a much more capable, flexible, and redundant system.

I would argue that had PTC been developed as a synergistic modular system addressing the various 'core requirements' more directly, some means of reading the switch positions or status wirelessly as well as via the CTC machine could easily be provided without a formal signal suppression.  And these then used with the GPS-based mutual train location part of PTC so that trains can run during an actual suppression -- even if the suppression is to tie other contacts in the same position sensor into the track circuits -- with positive, default safety against unexpected facing-point mislines.

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Posted by jeffhergert on Wednesday, February 14, 2018 5:28 PM
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Posted by coborn35 on Wednesday, February 14, 2018 6:13 PM

Randy Stahl

 

 He's thinking of the ARES system. 
VOLKER LANDWEHR

I think the promlem is that the railroads designed PTC as an overlay to the existing signal system. It depends on its functions. To connect the two you have to shut down the signals.

BN once designed ACSES as a stand-alone kind of PTC.

Track circuits are the best way to detect broken rails as required in 49 CFR 236.1005 (5)

Another paragraph of this is the reason given by the railroads for the overlay design:

§ 236.1007 Additional requirements for high-speed service.
(a) A
PTC railroad that conducts a passenger operation at or greater than 60 miles per hour or a freight operation at or greater than 50 miles per hour shall have installed a PTC system including or working in concert with technology that includes all of the safety-critical functional attributes of a block signal system meeting the requirements of this part, including appropriate fouling circuits and broken rail detection (or equivalent safeguards).
If this requirement really demanded for an overlay system or if a stand-alone with logic interconnection would have been possible I don't know. But even the temporary shut-down would have been necessary.
Regards, Volker
 

 

 

ACSES = Amtrak civil speed enforcement system. Not BN.

ACSES is an overlay to ATC.

 

Mechanical Department  "No no that's fine shove that 20 pound set all around the yard... those shoes aren't hell and a half to change..."

The Missabe Road: Safety First

 

  • Member since
    May, 2003
  • From: US
  • 13,202 posts
Posted by BaltACD on Wednesday, February 14, 2018 9:03 PM

jeffhergert

CSX has installed PTC on both Signalled and Dark territories.  

From my limited knowledge, I believe more effort and money was invested per mile in putting PTC in Dark territory as all Main track switches had to be equipped with 'reporting technology', electricity and radio stations to transmit the reports.

         

Never too old to have a happy childhood!

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