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Positive Train Control

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Posted by Railway Man on Monday, October 20, 2008 12:00 PM

I agree that the public pays no attention to railroad safety until there are mass casualties.  Then they demand their politicians create policy, and that was done in record speed this time.  However, PTC systems would likely have prevented a number of fatal collisions in recent years that involved only train crews:

  1. Carrizozo, New Mexico; February 20, 2004, two killed when train overran end of siding and collided with another freight train
  2. Devine, Texas, June 22, 1997, dispatcher error resulted in head-on, two killed (also two trespassers riding a trailing unit)
  3. Bertram, California, November 11, 2007, rear-end collision, two killed.

I could add more but any preventable injury to a railroader is one too many.

RWM

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Posted by SFbrkmn on Sunday, October 19, 2008 10:55 PM
The topic of PTC is now totally connected to the Mertolink accident. If that incident did not happen, the topic of PTC would not be making rr news as it is now. The recent Rail Safety Improvement Act of 2008 which the Senate passed and later signed into law by Bush last week calls for installation of PTC by 12/31/15 on all main trk where psgr/communter trains operate and where toxic haz mat shipments are hauled. Is this new system is the answer?, I don't know. If you look back at recent rr accidents involving deaths of general public,  some type of operational change manadated by law  became of it: engrs became certificated employees after the Amtrk/Conrail wreck @ Chase, MD in 1987, the FRA eng horn rule is a result of a crew that did not sound the eng horn until 6 seconds before going over a xing and killed a family in a auto, the NS train that ran into a open switch and hit the car of chlorine that killed 9 people resulted in the Switch Position forms that condrs have to keep updated. Now the Metrolink wreck and PTC is on the way. If the LA accident had not involved a psgr train w/ no release of haz mat products & no danger to the public, then it most likely would not have been a major issue since it did not involve the general public. Railroad employees have been killing each othr out on the ballast for 150 yrs but when it involves outsiders, then we get the knee jerk reaction from the industry & our friendly elected folks in DC who probably don;t know the difference between a drawbar & a knuckle pin but they "know' it all about rr signaling systems.
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Posted by sanvtoman on Thursday, October 16, 2008 7:02 PM

 Just don't want to see more transportation jobs lost.

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Posted by SALfan on Thursday, October 16, 2008 3:36 PM

jeaton

Fair warning.  Reading the regulation may cause your head to explode. 

Sounds like a typical government regulation.  After an hour of reading, you are willing to pay a hit man to put you out of your misery.

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Posted by oltmannd on Thursday, September 25, 2008 10:44 AM
 jeaton wrote:

And those old heads probably saw the movie Westworld "...  where nothing can possibly go wrong."

Probably a little more complicated than just saying so, but can the CPU do an integrity check on circuit components?  I don't know if transistors get stuck at a frequency more or less than mechanical relays, but I assume that there is no automatic feedback that warns of a stuck relay.

There are things you can do.  The LSL systems that Conrail put on had a watchdog timer to see if the program made it around it's loop.  If it hung up, the system would know it. It also would send a jolt to the magnet valve and measure the results to see if the coil was still in good shape.

Conrail wanted to put the cab signal display on the IFC/ICE screens, but they were never allowed to get rid of the separate cab display.

I once was show a "vital" signal relay that did get mechanically stuck.  The root cause of the failure turned out to be out-of-spec grease used in the rebuild of the relay.  The result was a false clear!

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

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Posted by jeaton on Thursday, September 25, 2008 8:39 AM

And those old heads probably saw the movie Westworld "...  where nothing can possibly go wrong."

Probably a little more complicated than just saying so, but can the CPU do an integrity check on circuit components?  I don't know if transistors get stuck at a frequency more or less than mechanical relays, but I assume that there is no automatic feedback that warns of a stuck relay.

"We have met the enemy and he is us." Pogo Possum "We have met the anemone... and he is Russ." Bucky Katt "Prediction is very difficult, especially if it's about the future." Niels Bohr, Nobel laureate in physics

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Posted by oltmannd on Thursday, September 25, 2008 7:38 AM

Part of it is trying to get old heads to think new thoughts.  Way back when, when the industry first started nibbling around at this and hired ARINC to write a complete set of specs for what was then called ATCS, the biggest stumbling block was getting past this notion of "fail safe - vital circuit".   If safety was maintained in a central office computer, was that computer "vital"?  Could any electronic circuit ever be considered "fail safe" in the same manner as a signal relay, which always (OK, almost always) drops due to gravity when denergized.  Transistors can get stuck in the "on" position....

It wouldn't surprise me if some of this muddled thinking got enshrined in the regs.

The game is about probability, I think.  There are no absolutes - even in the "vital - fail safe" world.

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

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Posted by AgentKid on Thursday, September 25, 2008 5:33 AM

I recall seeing a TV program about Air Traffic Control Systems back before 9/11 where various airlines were partnering with various equipment manufacturers to improve the system. Several good systems were developed but no airline would submit a system for FAA approval if all their competitors were going to be using the same system. Unbelievably they wanted to gain competitive advantage over one another based on the system they used and expected the taxpayers to pay more of the bill than they already do. I hope these equipment manufacturers, the railroads, the FRA, the NTSB and Capitol Hill don't get sucked into the same type of black hole.

AgentKid

 

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Posted by greyhounds on Monday, September 22, 2008 1:43 PM
 jeaton wrote:

 This is a link to CFR 49-236 Subpart H.                  http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=7d8e0068e9bf53874eb8a24dbbf9eb01&rgn=div6&view=text&node=49:4.1.1.1.30.8&idno=49

On my computer, reg comes to 33 pages, and a few hundred paragraphs in a font about this size.

Someone not interested might wonder if the author of the regulation has a serious case of Obssessive-Compulsive Disorder.  Before putting the system in use the railroad must provide documents of designs, tests and studies that proves that the system is safe and infallible.  Then they must prove that the tests, studies and documents are also infallible. 

Fair warning.  Reading the regulation may cause your head to explode. 

Yep.  The hardest part is not developing or installing a good PTC system.  The hardest part is understanding and complying with these regulations.

It would be understandable if someone trying to adopt a PTC system would look at this and decide they had better things to do.  These regs seem to be a real barrier to greater safety.

 

"By many measures, the U.S. freight rail system is the safest, most efficient and cost effective in the world." - Federal Railroad Administration, October, 2009. I'm just your average, everyday, uncivilized howling "anti-government" critic of mass government expenditures for "High Speed Rail" in the US. And I'm gosh darn proud of that.
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Posted by beaulieu on Monday, September 22, 2008 1:10 PM
 Railway Man wrote:

<snipped for brevity>

You might ask around in your circles why no U.S. railway has taken an interest in ETMS (European Train Management System).  We looked at it for a couple of developing-world railways and determined it was too expensive, too ponderous, too hard to configure, too hard to maintain, and too difficult to deal with the bureaucracy behind it.  They had no interest in helping match it to our railway systems' needs but wanted us to turn our railways upside down in order to meet their conception of what railways should be.

RWM

RWM

The system is properly ERTMS (European Railway Traffic Management System), it consists of two parts, a GSM-R (GSM-Rail) communications system, and ETCS (European Train Control System).  

Too expensive -  This isn't hard to understand for Developing World. What kind of application were you consulting on, busy commuter network with short headways? There are projects in various stages using Level 1 equipment in Korea, China, Saudi Arabia, and Mexico.

The problems with hard to deal with and being unwilling to adjust specifications is likely because they haven't yet reached critical mass yet in Europe and there is still pressure to water down the system leading to incompatabilities between countries. Particularly at the railway level the European Union is not being united without a struggle. Some of the biggest problem countries are not the ones that you would suspect. Some government bureaus make the labor unions look like pussycats.

The money that is going to be paid out to settle the claims in the Chatsworth accident will likely have paid for quite a bit of an ATC installation. 

 

ERTMS Website

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Posted by jeaton on Monday, September 22, 2008 12:14 PM

 This is a link to CFR 49-236 Subpart H.                  http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=7d8e0068e9bf53874eb8a24dbbf9eb01&rgn=div6&view=text&node=49:4.1.1.1.30.8&idno=49

On my computer, reg comes to 33 pages, and a few hundred paragraphs in a font about this size.

Someone not interested might wonder if the author of the regulation has a serious case of Obssessive-Compulsive Disorder.  Before putting the system in use the railroad must provide documents of designs, tests and studies that proves that the system is safe and infallible.  Then they must prove that the tests, studies and documents are also infallible. 

Fair warning.  Reading the regulation may cause your head to explode. 

"We have met the enemy and he is us." Pogo Possum "We have met the anemone... and he is Russ." Bucky Katt "Prediction is very difficult, especially if it's about the future." Niels Bohr, Nobel laureate in physics

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Posted by Railway Man on Monday, September 22, 2008 12:14 AM
 beaulieu wrote:

I wonder what would happen if they chose the European ETCS level 1 system. This system is made by all the European manufacturers except possibly Westinghouse (Siemens, Alcatel, Alstom, Bombardier, Ansaldo) presumeably GE-Harris would have access to the technical specifications since I believe they belong to a subsidiary of the UIC. Many(all?) of the European Signalling manufacturers have US Subsidiaries. Level 1 backs up the wayside signals, Level 2 adds cab-signalling meaning you can eliminate the lineside signals. Every manufacturer's equipment is compatible with the others. When the Swiss installed ETCS on the new Loetschberg Base Tunnel, Alstom won the contract for the lineside equipment, while Siemens and Bombardier split the contract to equip the locomotives.

You might ask around in your circles why no U.S. railway has taken an interest in ETMS (European Train Management System).  We looked at it for a couple of developing-world railways and determined it was too expensive, too ponderous, too hard to configure, too hard to maintain, and too difficult to deal with the bureaucracy behind it.  They had no interest in helping match it to our railway systems' needs but wanted us to turn our railways upside down in order to meet their conception of what railways should be.

RWM

RWM

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Posted by Railway Man on Monday, September 22, 2008 12:07 AM

 BaltACD wrote:
Individual roads, and the industry as a whole, do not want to be beholding to a single manufacturer.  There will have to be a definative standard for PTC written and enforced and open to all manufacturers to build equipment that complies and works within the standard.  Both the FRA and the AAR (as the representative of the carriers) will have their fingers in writing the standard.

The FRA has already written the regulation, CFR 49.236 Subpart H.  The FRA has no regulatory authority to enforce a vendor or architecture; Congress would have to grant that authority (presuming it's legal).

Time will tell if there is a common open standard or a common closed standard.  At the present time I would not rule the latter out as 4 of 7 have already announced one.

RWM

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Posted by jeaton on Sunday, September 21, 2008 11:56 PM
 beaulieu wrote:

I wonder what would happen if they chose the European ETCS level 1 system. This system is made by all the European manufacturers except possibly Westinghouse (Siemens, Alcatel, Alstom, Bombardier, Ansaldo) presumeably GE-Harris would have access to the technical specifications since I believe they belong to a subsidiary of the UIC. Many(all?) of the European Signalling manufacturers have US Subsidiaries. Level 1 backs up the wayside signals, Level 2 adds cab-signalling meaning you can eliminate the lineside signals. Every manufacturer's equipment is compatible with the others. When the Swiss installed ETCS on the new Loetschberg Base Tunnel, Alstom won the contract for the lineside equipment, while Siemens and Bombardier split the contract to equip the locomotives.

No one is suggesting that the various designers won't eventually be able to make interchangable systems to use on North American railroads.  At this point it doesn't appear that our railroads are ready to decide which system is the "best".  They will probably get there, but one railroad's favorite might now be considered too expensive by another railroad.  When dollars are at stake, compromise can be difficult.

"We have met the enemy and he is us." Pogo Possum "We have met the anemone... and he is Russ." Bucky Katt "Prediction is very difficult, especially if it's about the future." Niels Bohr, Nobel laureate in physics

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Posted by beaulieu on Sunday, September 21, 2008 11:21 PM

I wonder what would happen if they chose the European ETCS level 1 system. This system is made by all the European manufacturers except possibly Westinghouse (Siemens, Alcatel, Alstom, Bombardier, Ansaldo) presumeably GE-Harris would have access to the technical specifications since I believe they belong to a subsidiary of the UIC. Many(all?) of the European Signalling manufacturers have US Subsidiaries. Level 1 backs up the wayside signals, Level 2 adds cab-signalling meaning you can eliminate the lineside signals. Every manufacturer's equipment is compatible with the others. When the Swiss installed ETCS on the new Loetschberg Base Tunnel, Alstom won the contract for the lineside equipment, while Siemens and Bombardier split the contract to equip the locomotives.

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Posted by BaltACD on Sunday, September 21, 2008 8:58 PM
 Railway Man wrote:

A third possibility, not mentioned above, is that the Class I railroads will simply choose one manufacturer as the standard, and the interoperability problem will vanish, just as the railroads choose the Janney-pattern automatic coupler and not any of its competitors.  Whether they choose to do that through the AAR or independent of the AAR is not important as the AAR is an instrument of the railroads.

RWM

Individual roads, and the industry as a whole, do not want to be beholding to a single manufacturer.  There will have to be a definative standard for PTC written and enforced and open to all manufacturers to build equipment that complies and works within the standard.  Both the FRA and the AAR (as the representative of the carriers) will have their fingers in writing the standard.

Never too old to have a happy childhood!

              

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Posted by Railway Man on Sunday, September 21, 2008 8:28 PM

It's not an ego problem.  It's a technical problem.  The architectures are very different.  You might as well demand that narrow-gauge railroads and standard-gauge railroads set aside their differences and run on each other yet still maintain their own gauge.

A third possibility, not mentioned above, is that the Class I railroads will simply choose one manufacturer as the standard, and the interoperability problem will vanish, just as the railroads choose the Janney-pattern automatic coupler and not any of its competitors.  Whether they choose to do that through the AAR or independent of the AAR is not important as the AAR is an instrument of the railroads.

RWM

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Posted by BaltACD on Sunday, September 21, 2008 4:25 PM
 tree68 wrote:

Given the nature of railroad operations today (ie, runthroughs, leasing, etc) I suspect that compatability between systems is the single largest bugaboo.  I suspect that it will be a while before the various system designers can set aside their corporate egos and decide on a common operating schema that will allow a locomotive to travel coast-to-coast as the controlling/monitored unit.

That may well be why the PTC systems are being labelled as "under development."

 

Fully agree that the compatability issues are the biggest hurdle to the acceptance of any innovation in the rail industry. 

All of the PTC systems undergoing testing at present, appear to be mutually exclusive in their ability to operate with the other systems.  With the train control systems that are currently in, and have been in, operation there is not FULL compatability.  It will ultimately be up to the FRA and the AAR to develop a definative standard for for universal applicability.  Without unversal applicability you have nothing, or you have resource utilization (locomotives) seriously reduced to the point of eliminating most of the 'run-through' gains that have enhanced railroad efficiency since the enactment of the Staggers Act.

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Posted by tree68 on Sunday, September 21, 2008 3:44 PM

Given the nature of railroad operations today (ie, runthroughs, leasing, etc) I suspect that compatability between systems is the single largest bugaboo.  I suspect that it will be a while before the various system designers can set aside their corporate egos and decide on a common operating schema that will allow a locomotive to travel coast-to-coast as the controlling/monitored unit.

That may well be why the PTC systems are being labelled as "under development."

 

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Positive Train Control
Posted by jeaton on Sunday, September 21, 2008 3:18 PM

This subject has been part of the many threads started covering the Metrolink accident, but I am starting this for a more focused discussion of the subject.

PTC vs. two men.  I'll agree that either condition might have prevented the Metrolink accident. However, while I can't back it up with facts, but it is my opinion that existing PTC systems can provide a greater degree of safety than that provided with the "second man" in the engine or control cab.  It seems possible that for the passenger end of the business PTC may also be less costly than the second man.  How many new jobs would be required for to cover the second man position?  Wages, payroll taxes and benefits might run $75 to a $100 thousand per man.  If it is only 1000 jobs, the cost then becomes $75 to a $100 million per year. 

Compatable systems.  I understand that several vendors are offering systems.  I do not know where it is at, but it is obvious that the equipment on the locomotive (or cab car) would have to work on every property.  We all know that freight locomotives of a given ownership can be found on foreign lines all over the country.  Passenger locomotives might be more tightly assigned to a given route, but it is rather common for a passenger route will be on tracks of more than one ownership.

Technology.  After Metrolink, someone from the AAR said that PTS technology is still being developed.   What specificly is the technology that the AAR spolesman addressing?  I know that the State of Illinois was attempting to put in a PTC system.  Their system was to include a feature where the software would define the lenght of the track segment as a block depending on the speed and stopping characteristics of a train.  That, as opposed to blocks of fixed length now set for ABS territory.  I have the impression that IDOT abandoned the project because of problems programming the logic and designing the hardware for the variable block system.  (They may have also run out of funding for the project.) IDOT is now looking at a classic ATS sytem to meet FRA rules for higher speed operation.

Regulations.  I have heard that even though the FRA seeks enhanced safety, they require extraordinary demonstrated proof that a new system is safer than the old.  I think that the specifics for PTC are that it is now only allowed as an overlay to the existing dispatch functions and the authority for a train to occupy a segment of track must still be conveyed by track warrants for TWC territory and existing signal systems for CTC territory.  In other words the "hardwired" signal equipment with the associated costs must remain in place.  I am not sure about this, but it might even mean that putting PTC in dark territory would still require track warrants to be issued over the radio and and copied on paper by the crew.  Perhaps existing dark territory speed limits would remain in force.

Reactive vs. predictive.  As I understand the systems, ATS stops a train when an engineer overruns a signal or authority limit.  PTC looks ahead and when the engineer fails to do so, starts the speed reduction process in time for a safe stop.

Cost.  A 2004 study done for the FRA came up with the following range of estimates for PTC installation on Class 1's  (2001 dollars.  Numbers rounded.)  100,000 route miles, $8,000 to $24,000 per mile.  21,000 locomotives $20,000 to $75,000 each plus cost for central office for total costs of $1.3 to $4.4 billion.  The numbers came from various pilot project underway at the time of the study and the range is partially attributed to differences in features making up the system.  The study heavily focuses on potential savings from operating efficiencies and can be found at http://www.tsd.org/papers/FRA%20PTC%20final%20report%2003-16-04.pdf

 

"We have met the enemy and he is us." Pogo Possum "We have met the anemone... and he is Russ." Bucky Katt "Prediction is very difficult, especially if it's about the future." Niels Bohr, Nobel laureate in physics

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