BaltACDThe delayed in block rules are an outgrowth of the MARC vs. Capitol Limited collision that happened control point Georgetown Jct in Silver Spring, MD in 1996.
I think you will find that rule may go a lot further back, although perhaps not on all roads. Part of Rule 514 in a 1951 CPR Rule Book (Canadian UCOR) is:
"When a train or engine has passed a signal permitting it to proceed and is delayed in the block, it must proceed at restricted speed to the next signal."
I did not immediately find an exact upper limit for speed, but the 1962 version called for no more than 15mph (slow speed).
John
Remember Delayed in the Block in GCOR is different in respect to ABS or CTC. In ABS, proceed at restricted speed until next signal is visible, displays a proceed indication and the track is seen to be clear to the signal. In CTC it's proceed prepared to stop at the next signal. (There ued to be a provision not to exceed 30 mph for freight trains, but it's been gone for quite a few years now.)
In my limited experience in such a scenario, once when there were facing point hand switches in CTC, the PTC screen showed restricted speed hash boxes only at the switches, not the entire block and asked for verifiction of the way the switches were lined before removing the hash boxes.
I haven't worked out one territory that is ABS/TWC/PTC. I don't know how DIB works up there.
Jeff
oltmannd dpeltier Again, I'm no expert, but I'm pretty sure that's not true. It is possible that PTC will raise a warning if a train crew tries to release an authority while they're still within its limits. But preventing a premature release of authority is actually quite different from what you said - namely, that PTC would prevent the dispatcher from issuing an authority to another train. That is not the role of PTC, but of the Computer-Aided Dispatcher (CAD) software on the dispatcher's workstation. These systems were pretty sophisticated well before PTC came along. PTC doesn't control the issuance of authorities, just keeps trains within their authorities. The PTC test train I rode a few years ago was testing the release of authority behind the train in signalled territory. PTC would give the train an authority of 20 miles, lets say, and the system needed to roll up that authority behind the train block at a time so another could follow. They were also testing "delayed in block" functonality, although I can't fathom why you need that in PTC territory unless you're concerned about a broken rail occuring during the delay or some such thing.
dpeltier Again, I'm no expert, but I'm pretty sure that's not true. It is possible that PTC will raise a warning if a train crew tries to release an authority while they're still within its limits. But preventing a premature release of authority is actually quite different from what you said - namely, that PTC would prevent the dispatcher from issuing an authority to another train. That is not the role of PTC, but of the Computer-Aided Dispatcher (CAD) software on the dispatcher's workstation. These systems were pretty sophisticated well before PTC came along. PTC doesn't control the issuance of authorities, just keeps trains within their authorities.
The PTC test train I rode a few years ago was testing the release of authority behind the train in signalled territory. PTC would give the train an authority of 20 miles, lets say, and the system needed to roll up that authority behind the train block at a time so another could follow.
They were also testing "delayed in block" functonality, although I can't fathom why you need that in PTC territory unless you're concerned about a broken rail occuring during the delay or some such thing.
Not sure I understand your first paragraph fully, but I'm reasonably certain that in CTC territory the PTC computer doesn't keep an independent version of "authority limits" that's any different from the signal system, and that in dark territory it doesn't keep anything different from what the track warrant says. Because most authorities don't allow for unlimited backup moves, it does have to keep track of where the rear end is and it how far back it can move legally, but it doesn't "roll up" anything to the dispatcher.
Regarding your second paragraph, I believe that, even with every train using PTC, the delayed in block rule is still required to protect against certain kinds of problems. Consider a situation where you have an electric lock switch in CTC territory. Train A passes the block signal in advance of the switch points and then stops. Train B starts running time on the electric lock, and after it runs they open the switch. Meanwhile Train A starts moving again and accelerates quickly, so that when they get to the switch they can't stop and they crash into Train B. The DIB rule is supposed to prevent this from happening. (Of course, Train B's crew shouldn't have opened the switch without permission, and the dispatcher shouldn't have given permission if Train A was going to proceed across the switch... but these processes are not failsafe.)
Would PTC somehow prevent this from happening even without DIB? No. In signaled territory, PTC doesn't directly monitor each switch position; the signal system detects open switches and responds accordingly, then the PTC enforces the signals. Train A got a clear signal when they entered the block, and probably has a clear signal at the next block, so without DIB the PTC on Train A will allow maximum authorized speed. Train B never even came out on the main line, so there is nothing for its computer to enforce.
So you still need DIB.
Dan
BaltACD jeffhergert There is now a requirement for a stop test of every engineer at least once a year under a PTC-Restricted Speed scenario. I don't know if it's a FRA or company requirement. I've had one about 6 weeks ago. The on-board PTC does not see other trains, whether on the same or adjacent track, going in either direction. The master, back office big brain may know where everything is, at least the head end of trains, but the on board brain doesn't Jeff Before I retired, I heard Road Foremen of Engines discussing the need for 'Banner Testing' Engineers for Restricted Speed Compliance - I don't know if there was a requirement to test each Engineer each year or not. Shortly after EHH took command the Road Foreman of Engines postions were abolished system wide. I have no idea who, if anyone, is performing the functions that the RFE's did.
jeffhergert There is now a requirement for a stop test of every engineer at least once a year under a PTC-Restricted Speed scenario. I don't know if it's a FRA or company requirement. I've had one about 6 weeks ago. The on-board PTC does not see other trains, whether on the same or adjacent track, going in either direction. The master, back office big brain may know where everything is, at least the head end of trains, but the on board brain doesn't Jeff
The on-board PTC does not see other trains, whether on the same or adjacent track, going in either direction. The master, back office big brain may know where everything is, at least the head end of trains, but the on board brain doesn't
Before I retired, I heard Road Foremen of Engines discussing the need for 'Banner Testing' Engineers for Restricted Speed Compliance - I don't know if there was a requirement to test each Engineer each year or not.
Shortly after EHH took command the Road Foreman of Engines postions were abolished system wide. I have no idea who, if anyone, is performing the functions that the RFE's did.
I think there is an FRA requirement for a certain number of stop tests, but a company can require more. A stop test can be done by any manager. Stopping for an absolute signal, even if it wasn't structured by the manager (having the dispatcher purposely hold the signal) can count.
Once we stopped at our crew change point, just short of a control point. A lower level manager got on board and checked off a number of tests (we passed all) we would be credited with. I noticed one for me was for stopping for the signal, and stopping where stop must be made. I didn't say anything, but the signal we stopped at was a Restricting. The signal didn't require a stop, the crew change did.
BaltACD zugmann BaltACD Shortly after EHH took command the Road Foreman of Engines postions were abolished system wide. I have no idea who, if anyone, is performing the functions that the RFE's did. Trainmasters with engineer cards? I am being told that 'Trainmasters' are doing downloads and 'Certification Rides' are being peformed on a simulator and signed off by 'Trainmasters' that have no idea what a train is or does.
zugmann BaltACD Shortly after EHH took command the Road Foreman of Engines postions were abolished system wide. I have no idea who, if anyone, is performing the functions that the RFE's did. Trainmasters with engineer cards?
BaltACD Shortly after EHH took command the Road Foreman of Engines postions were abolished system wide. I have no idea who, if anyone, is performing the functions that the RFE's did.
Trainmasters with engineer cards?
I am being told that 'Trainmasters' are doing downloads and 'Certification Rides' are being peformed on a simulator and signed off by 'Trainmasters' that have no idea what a train is or does.
I've heard of that happening here to for the intial cert ride for engineers. That was some time ago.
I've heard a couple of times when we had planned detours over other railroads, they qualified our people who were going to act as Pilots by giving them a ride over the territory in a high-rail pickup.
SD70Dude Yikes! The blind qualifying the blind!
Yikes! The blind qualifying the blind!
Johnny
Greetings from Alberta
-an Articulate Malcontent
Never too old to have a happy childhood!
BaltACDShortly after EHH took command the Road Foreman of Engines postions were abolished system wide. I have no idea who, if anyone, is performing the functions that the RFE's did.
It's been fun. But it isn't much fun anymore. Signing off for now.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any
That is very bad news indeed, in my experience the RFE group is able to reign in or shoot down the idiotic whims and ideas that other managers (without on-the-ground railroad experience) come up with.
Removing that buffer will lead to the idiotic ideas being given free reign and that will cause accidents, if it has not already.
jeffhergertThere is now a requirement for a stop test of every engineer at least once a year under a PTC-Restricted Speed scenario. I don't know if it's a FRA or company requirement. I've had one about 6 weeks ago. The on-board PTC does not see other trains, whether on the same or adjacent track, going in either direction. The master, back office big brain may know where everything is, at least the head end of trains, but the on board brain doesn't Jeff
oltmannd jeffhergert oltmannd tree68 oltmannd PTC can't enforce restricting because there's no way of knowing the end point of the authority. I would submit that PTC can't enforce restricted speed because it doesn't have eyes. The limits of restricted speed may be known. What is not always known is the conditions that require it. This would be why PTC would only enforce the maximum allowable speed under restricted speed. This could occur on main track. I wonder if PTC does enforce slow speed when restricting speed is indicated (such as being "talked by" a stop signal? Anybody know? PTC allows you pass an intermediate (non-absolute) signal at restricted speed. PTC gives a warning at 18 mph and initiates a brake application when speed goes over 21 mph, speeds as indicated on the PTC screen. (Speed on the locomotive's speedometer may differ by a few mph either way. My experience has been that usually the PTC indicated speed is 1 to 2 mph less than the locomotive indicated speed.) The same conditions apply when talked by an absolute signal. Jeff This is interesting. Thanks for taking the time to explain so clearly. So, if there is a train in that block, does PTC try to enforce a movement authority to the end of that train or will it just let you run smack into it at 20 mph? That would kinda take the "positive" out of PTC. I get the "talking by" an absolute. Signal could be broken - in which case PTC is, too. Or you could be tucking in a siding behind another train - which makes it look more like the first case.
jeffhergert oltmannd tree68 oltmannd PTC can't enforce restricting because there's no way of knowing the end point of the authority. I would submit that PTC can't enforce restricted speed because it doesn't have eyes. The limits of restricted speed may be known. What is not always known is the conditions that require it. This would be why PTC would only enforce the maximum allowable speed under restricted speed. This could occur on main track. I wonder if PTC does enforce slow speed when restricting speed is indicated (such as being "talked by" a stop signal? Anybody know? PTC allows you pass an intermediate (non-absolute) signal at restricted speed. PTC gives a warning at 18 mph and initiates a brake application when speed goes over 21 mph, speeds as indicated on the PTC screen. (Speed on the locomotive's speedometer may differ by a few mph either way. My experience has been that usually the PTC indicated speed is 1 to 2 mph less than the locomotive indicated speed.) The same conditions apply when talked by an absolute signal. Jeff
oltmannd tree68 oltmannd PTC can't enforce restricting because there's no way of knowing the end point of the authority. I would submit that PTC can't enforce restricted speed because it doesn't have eyes. The limits of restricted speed may be known. What is not always known is the conditions that require it. This would be why PTC would only enforce the maximum allowable speed under restricted speed. This could occur on main track. I wonder if PTC does enforce slow speed when restricting speed is indicated (such as being "talked by" a stop signal? Anybody know?
tree68 oltmannd PTC can't enforce restricting because there's no way of knowing the end point of the authority. I would submit that PTC can't enforce restricted speed because it doesn't have eyes. The limits of restricted speed may be known. What is not always known is the conditions that require it. This would be why PTC would only enforce the maximum allowable speed under restricted speed. This could occur on main track.
oltmannd PTC can't enforce restricting because there's no way of knowing the end point of the authority.
I would submit that PTC can't enforce restricted speed because it doesn't have eyes.
The limits of restricted speed may be known. What is not always known is the conditions that require it. This would be why PTC would only enforce the maximum allowable speed under restricted speed.
This could occur on main track.
I wonder if PTC does enforce slow speed when restricting speed is indicated (such as being "talked by" a stop signal? Anybody know?
PTC allows you pass an intermediate (non-absolute) signal at restricted speed. PTC gives a warning at 18 mph and initiates a brake application when speed goes over 21 mph, speeds as indicated on the PTC screen. (Speed on the locomotive's speedometer may differ by a few mph either way. My experience has been that usually the PTC indicated speed is 1 to 2 mph less than the locomotive indicated speed.) The same conditions apply when talked by an absolute signal.
This is interesting. Thanks for taking the time to explain so clearly.
So, if there is a train in that block, does PTC try to enforce a movement authority to the end of that train or will it just let you run smack into it at 20 mph? That would kinda take the "positive" out of PTC.
I get the "talking by" an absolute. Signal could be broken - in which case PTC is, too. Or you could be tucking in a siding behind another train - which makes it look more like the first case.
PTC recognizes the block is occupied due to the signal system. (I don't work dark territory with PTC. I don't believe we have any dark-PTC territory in my area.) It, like the signal system does not know why there is an indicated occupancy. It could be an open switch (PTC will ask the position of facing point hand throws and stop you short if you don't verify the switch alignment.), a broken rail or a train. Other than the switch, a fixed location, it won't know where in the block the cause for the occupncy is. Yes, it will allow you to run into something at 20mph.
There is now a requirement for a stop test of every engineer at least once a year under a PTC-Restricted Speed scenario. I don't know if it's a FRA or company requirement. I've had one about 6 weeks ago.
tree68 oltmannd They were also testing "delayed in block" functonality, although I can't fathom why you need that in PTC territory unless you're concerned about a broken rail occuring during the delay or some such thing. "Delayed in block" is a regular part of Amtrak's radio vocabulary, account station stops. "Amtrak 789 departing Podunk, delayed in block, in on a clear."
oltmannd They were also testing "delayed in block" functonality, although I can't fathom why you need that in PTC territory unless you're concerned about a broken rail occuring during the delay or some such thing.
"Delayed in block" is a regular part of Amtrak's radio vocabulary, account station stops.
"Amtrak 789 departing Podunk, delayed in block, in on a clear."
The delayed in block rules are an outgrowth of the MARC vs. Capitol Limited collision that happened control point Georgetown Jct in Silver Spring, MD in 1996. The MARC train entered a station stop on an Approach Signal (prepared to STOP at next signal), however the crew departed the station stop as if they were operating on a Clear Signal (proceed at maximum authorized speed). MARC train being operated in push service came around a curved to find a STOP signal displayed and being unable to stop their train collided with the locomotives of the Capitol Limited that was moving through crossovers from #2 track to #1 track. Eight people on the MARC train died including the entire crew.
https://www.ntsb.gov/investigations/AccidentReports/Pages/RAR9702.aspx
oltmanndThey were also testing "delayed in block" functonality, although I can't fathom why you need that in PTC territory unless you're concerned about a broken rail occuring during the delay or some such thing.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
dpeltierAgain, I'm no expert, but I'm pretty sure that's not true. It is possible that PTC will raise a warning if a train crew tries to release an authority while they're still within its limits. But preventing a premature release of authority is actually quite different from what you said - namely, that PTC would prevent the dispatcher from issuing an authority to another train. That is not the role of PTC, but of the Computer-Aided Dispatcher (CAD) software on the dispatcher's workstation. These systems were pretty sophisticated well before PTC came along. PTC doesn't control the issuance of authorities, just keeps trains within their authorities.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
oltmanndSo, if there is a train in that block, does PTC try to enforce a movement authority to the end of that train or will it just let you run smack into it at 20 mph? That would kinda take the "positive" out of PTC.
This goes back to the basic definition of "restricted speed." Able to stop within half of ones sight distance. The maximum speed is not a factor in that - and it varies by railroad.
I have ridden a train that stopped at a signal, anf then moved up slowly until it was close to another train on the same track. Three years ago, I was waiting in Providence for an NE Corridor train which was running late--and an MBTA train left Providence ahead of my train. Along the way, the MBTA train made a stop at one of its stations; we stopped at the block signal, and then crept up the MBTA train--and followed it into Back Bay and then on into South Station.
While walkng to the station, I came up with the engineer and asked if that was what he had done, and said that it was.
jeffhergertThere are two kinds of cut out. "Sot" cut out and "Hard" cut out. There are conditions that require a soft cut out and can be done without permission. A soft cut out is performed by pushing the cut out soft key button. PTC asks if you want to suspend enforcement. Once the conditions for having to soft cut out end, another button (cut in) will re-establish enforcement, after asking if this is what you want to do. Hard cut out is done by opening three toggle switches located in a sealed box in the nose. Each toggle switch is also sealed. The dispatcher's permission is required for this. I've only had to hard cut out one engine. That was when, even in soft cut out, the PTC system was still cutting out the automatic air brake valve on the lead locomotive without warning or penalty. Jeff
Hard cut out is done by opening three toggle switches located in a sealed box in the nose. Each toggle switch is also sealed. The dispatcher's permission is required for this.
I've only had to hard cut out one engine. That was when, even in soft cut out, the PTC system was still cutting out the automatic air brake valve on the lead locomotive without warning or penalty.
And when I was still working - Dispatchers had to get permission from the headquarters locomotive mechanical staff - who would have been working with the engineer of the locomotive that was having problems before they could issue permission for PTC to be cut out.
VOLKER LANDWEHR dehusman Then you are only discussing trying to prevent collisions between trains operating in signaled territory or on a joint authority mandatory directive. This thread started as follow up to the Arizona accident thread where the question arose if PTC had to prevent that accident. This thread was the attempt to bundle the answer. That doesn't mean the discussion is limited to this topic. In this light I didn't understand your post. As Zugmann said "restricted speed" is an operation procedure not a speed. dehusman This discussion then would not consider collisions in non-signalled territory, in tracks other than a main track or in yard limits, all of which would fall outside the scope of 49 CFR 236.1005. If I understood PTC correctly dark territory is not exempted from PTC when it fulfills the requirements that make PTC necessary in signaled territory. The dispatcher still issues track warrants by voice/data radio und PTC enforces the movement authorities. Mainline switches and derails must be tied into the PTC system. A stand-alone system would be able to avoid train collisions in dark territory too. A reworked I-EMTS might be able sometime too. In my point of view the PTC mandate was kept as small as possible, enough to prevent those accidents that endanger train passengers and the public most. Accidents among railroaders were not considered important enough, I fear. dehusman How do you tell the PTC system that you are adding an engine to the train intentionally, and that it is not a case of an engine running into a standing train? The difference between a collison and a coupling is intent. With the permission of the dispatcher the PTC system can be cut out. Here are some PTC locomotive displays: www.smartlocal202.org/site/assets/files/BNSF/BN_ROAD/PTC_Screen_Elements_9_27_2012.pdf On page 1 under PTC-System States it shows "Cut Out" with the above explanation.Regards, Volker
dehusman Then you are only discussing trying to prevent collisions between trains operating in signaled territory or on a joint authority mandatory directive.
This thread started as follow up to the Arizona accident thread where the question arose if PTC had to prevent that accident. This thread was the attempt to bundle the answer.
That doesn't mean the discussion is limited to this topic. In this light I didn't understand your post. As Zugmann said "restricted speed" is an operation procedure not a speed.
dehusman This discussion then would not consider collisions in non-signalled territory, in tracks other than a main track or in yard limits, all of which would fall outside the scope of 49 CFR 236.1005.
If I understood PTC correctly dark territory is not exempted from PTC when it fulfills the requirements that make PTC necessary in signaled territory. The dispatcher still issues track warrants by voice/data radio und PTC enforces the movement authorities. Mainline switches and derails must be tied into the PTC system.
A stand-alone system would be able to avoid train collisions in dark territory too. A reworked I-EMTS might be able sometime too.
In my point of view the PTC mandate was kept as small as possible, enough to prevent those accidents that endanger train passengers and the public most. Accidents among railroaders were not considered important enough, I fear.
dehusman How do you tell the PTC system that you are adding an engine to the train intentionally, and that it is not a case of an engine running into a standing train? The difference between a collison and a coupling is intent.
With the permission of the dispatcher the PTC system can be cut out. Here are some PTC locomotive displays: www.smartlocal202.org/site/assets/files/BNSF/BN_ROAD/PTC_Screen_Elements_9_27_2012.pdf
On page 1 under PTC-System States it shows "Cut Out" with the above explanation.Regards, Volker
There are two kinds of cut out. "Soft" cut out and "Hard" cut out. There are conditions that require a soft cut out and can be done without permission. A soft cut out is performed by pushing the cut out soft key button. PTC asks if you want to suspend enforcement. Once the conditions for having to soft cut out end, another button (cut in) will re-establish enforcement, after asking if this is what you want to do.
BN had experimented with ARES, a stand-alone system. The merger with ATSF ended the project.
There would have been a starting point for a stand-alone system. It is said it would have been too expensive and time consuming to finally develop it.
Wagging tongues suggest that tasking the signal departments with PTC development and implementation was the end of the stand-alone system as it would make many signals surplus.
Here is video about BNSF's PTC system: https://youtu.be/7fDRazEWAKURegards, Volker
oltmannd BaltACD oltmannd There is two way communication from the train to the back office. Trains have to tell the back office that the data has been received and is in good shape. Train also have to "release" the movement authorities they have used. Kind of like reporting clear in manual block. Trains don't do the reporting - track circuits in signalled territory do the reporting. Train crews do the reporting in TWC territory. Correct, but PTC does it, too. It's not "vital", but PTC won't let out another movement authority for a following train until the leading train "clears up" behind it. It's "both/and" the way I understand it.
BaltACD oltmannd There is two way communication from the train to the back office. Trains have to tell the back office that the data has been received and is in good shape. Train also have to "release" the movement authorities they have used. Kind of like reporting clear in manual block. Trains don't do the reporting - track circuits in signalled territory do the reporting. Train crews do the reporting in TWC territory.
oltmannd There is two way communication from the train to the back office. Trains have to tell the back office that the data has been received and is in good shape. Train also have to "release" the movement authorities they have used. Kind of like reporting clear in manual block.
Trains don't do the reporting - track circuits in signalled territory do the reporting. Train crews do the reporting in TWC territory.
Correct, but PTC does it, too. It's not "vital", but PTC won't let out another movement authority for a following train until the leading train "clears up" behind it. It's "both/and" the way I understand it.
Again, I'm no expert, but I'm pretty sure that's not true. It is possible that PTC will raise a warning if a train crew tries to release an authority while they're still within its limits.
But preventing a premature release of authority is actually quite different from what you said - namely, that PTC would prevent the dispatcher from issuing an authority to another train. That is not the role of PTC, but of the Computer-Aided Dispatcher (CAD) software on the dispatcher's workstation. These systems were pretty sophisticated well before PTC came along. PTC doesn't control the issuance of authorities, just keeps trains within their authorities.
As I said at the top, it seems to me that preventing train-to-train collisions at restricting speed would require you to implement most of what you would need for moving block. The only thing PTC can do is ensure that each train stays within it's limits, so the only way to keep two trains from ever being in the same place at the same time is to never have overlapping limits. The only way to let trains get very, very close to each other without overlapping limits is to have authority limits that tightly match your trains exact location - which is basically what a moving block is..
Some others have suggested that it was a "choice" to implement PTC in the way it was implemented, and in some sense that's true. But the choice was dictated by the desire to have PTC invented and installed from 0 to 100% in seven years (later extended to ten years). At the time, there were, what, three systems in revenue service on the North American railroad network (not counting PATH) that had most of the desired safety features for PTC (ETMS, ASCES, ITC). All of them used basically the same block-system paradigm, and none of them had any ability to do moving blocks (or to prevent all train-to-train collisions at restricting speed). The notion that a moving block system, which had been tried and failed several years earlier in the NAJPTC project, would be invented from nothing and deployed nationwide in seven years was apparently so ludicrous that even Congress accepted it.
zugmannSlow speed under NORAC is not to exceed 15mph. Restricting can allow up to 20mph unless there's other considerations ( for example - through interlockings for us).
Interesting. Restricting on Conrail had a max of 15 mph. Slow speed was 15 mph...
dehusmanThen you are only discussing trying to prevent collisions between trains operating in signaled territory or on a joint authority mandatory directive.
dehusmanThis discussion then would not consider collisions in non-signalled territory, in tracks other than a main track or in yard limits, all of which would fall outside the scope of 49 CFR 236.1005.
dehusmanHow do you tell the PTC system that you are adding an engine to the train intentionally, and that it is not a case of an engine running into a standing train? The difference between a collison and a coupling is intent.
zugmannBut then again - restricted speed is not a speed; but a method of operation. Slow speed is just that. A speed.
For us, restricted speed is not to exceed 10 in the yard (by timetable instruction), and 20 on the main. NORAC calls for 15 in interlockings.
I haven't done a detailed search, but I don't think the word "restricting" appears in NORAC. I could be wrong.
zugmann oltmannd Understand completely. You can never exceed "slow" speed when operating under restricting. Slow implies a clear route. Restricting does not. PTC can't do restricting. Slow speed under NORAC is not to exceed 15mph. Restricting can allow up to 20mph unless there's other considerations ( for example - through interlockings for us). But then again - restricted speed is not a speed; but a method of operation. Slow speed is just that. A speed.
oltmannd Understand completely. You can never exceed "slow" speed when operating under restricting. Slow implies a clear route. Restricting does not. PTC can't do restricting.
Slow speed under NORAC is not to exceed 15mph. Restricting can allow up to 20mph unless there's other considerations ( for example - through interlockings for us).
But then again - restricted speed is not a speed; but a method of operation. Slow speed is just that. A speed.
CSX Rules define the upper limit of both Slow Speed and Restricted Speed at 15 MPH. Needless to say Restricted Speed has all the other conditions attached to it and Slow Speed does not have those conditions.
oltmanndUnderstand completely. You can never exceed "slow" speed when operating under restricting. Slow implies a clear route. Restricting does not. PTC can't do restricting.
BaltACD oltmannd tree68 oltmannd PTC can't enforce restricting because there's no way of knowing the end point of the authority. I would submit that PTC can't enforce restricted speed because it doesn't have eyes. The limits of restricted speed may be known. What is not always known is the conditions that require it. This would be why PTC would only enforce the maximum allowable speed under restricted speed. This could occur on main track. I wonder if PTC does enforce slow speed when restricting speed is indicated (such as being "talked by" a stop signal? Anybody know? Slow Speed and Restricted Speed are not the same. When operating at Slow Speed there is no requirement to be on the lookout for the things that are mentioned in the rule book definition of Restricted Speed.
Slow Speed and Restricted Speed are not the same. When operating at Slow Speed there is no requirement to be on the lookout for the things that are mentioned in the rule book definition of Restricted Speed.
Understand completely. You can never exceed "slow" speed when operating under restricting. Slow implies a clear route. Restricting does not. PTC can't do restricting.
Our community is FREE to join. To participate you must either login or register for an account.