Eastern Railroad Discussion > cab signals on the ex-RF&P

Credit to Jersey Mike's blog on signals: CSX filed last month to discontinue cab signals on the ex-RF&P. Time marches on. Can download the document at https://www.regulations.gov/document/FRA-2021-0111-0001. 

It's not an issue of "time marches on" as NS has been expanding its PRR cab signal network and integrated them with the ETMS PTC system to reduce reliance on maintaining wireless links with the signal locations.  It's an issue of CSX, VRE and Amtrak seeing short term cost savings at the expense of longer term higher speed passenger operations. 

The RF&P is turning into a state owned passenger corridor like the Amtrak Harrisburg Line, Hudson Line and Springfield Line.  Each of those three operate under Rule 562 + ACSES with stretches of 110mph operation that were quietly implemented without much fuss.  Meanwhile in the Midwest the ITSC and ETMS based PTC on the Michigan and Lincoln corridors are notorious for their constant problems.

From a passenger rail policy perspective DC to Richmond should look like DC to Boston.  Amtrak already supports ETMS on the corridor for NS and CSX freights in place of ACSES (but not cab signals). Running the 562 out to Manassas would allow VRE to operate soely on ACSES as well.  It would also double the number of signal blocks to support an increased train frequency. 

ctillnc Wrote:
> CSX filed last month to discontinue cab signals on the
> ex-RF&P. 

Say it ain't so! So no more RF&P units leading R172/R171 to/from New Jersey?
/Ted

Does PTC make cab signals redundant?

With PTC and it's current state of refinement, it's probably only a matter of time before the request is granted. I believe a year or two ago, CSX petitioned the FRA to remove the speed enforcement aspect of the cab signal system since that is something PTC takes care of. This latest incarnation appears to request the removal of the entire cab signal system.

While I am indifferent to the removal of the cab signals, there are limitations of the PTC system in place that would be nice if they were resolved before getting rid of the cab signals entirely. For one, if the cab signal improves from an approach in the cab to something better, you can go with that indication. When outside of cab signal territory and the condition of the block improves, you still have to go by the last wayside (approach) and approach the next signal prepared to comply with something red staring you in the face. If they get rid of the cab signals on the RF&P, no more in-block upgrades from approach to something better.

Additionally, there are places where the cab signal (and wayside) will upgrade but PTC will hold you to restricting until the next block. I can't tell you how frustrating it is to have a medium clear wayside and cab indication coming out of the siding at N Doswell but PTC decides to hold you to restricted speed until almost Chandler for some reason. I brought this up to an official a while back and his exact response was "PTC is designed to be more restrictive"....proving once again that the people running the show have no intention of doing any real "railroading"..... that's not an answer, sir....

Fr8engineer Wrote:
-------------------------------------------------------
> While I am indifferent to the removal of the cab
> signals, there are limitations of the PTC system
> in place that would be nice if they were resolved
> before getting rid of the cab signals entirely.
> For one, if the cab signal improves from an
> approach in the cab to something better, you can
> go with that indication. When outside of cab
> signal territory and the condition of the block
> improves, you still have to go by the last wayside
> (approach) and approach the next signal prepared
> to comply with something red staring you in the
> face. If they get rid of the cab signals on the
> RF&P, no more in-block upgrades from approach to
> something better.

Good point.  Also, I believe that cab signals allow a stopped train to depart a location based on the cab signal indication when no wayside signal is present.  That means that a passenger train stopped at a station can depart and operate based on the cab signal indication instead of having to operate prepared to stop at the next wayside signal.  In non-cab signalled territory, do the PTC rules allow stopped trains to proceed at maximum speed based solely on the PTC display, or do they have to operate prepared to stop at the next wayside signal regardless of what the PTC display shows?   

> Additionally, there are places where the cab
> signal (and wayside) will upgrade but PTC will
> hold you to restricting until the next block. I
> can't tell you how frustrating it is to have a
> medium clear wayside and cab indication coming out
> of the siding at N Doswell but PTC decides to hold
> you to restricted speed until almost Chandler for
> some reason. I brought this up to an official a
> while back and his exact response was "PTC is
> designed to be more restrictive"....proving once
> again that the people running the show have no
> intention of doing any real "railroading".....
> that's not an answer, sir....

What a lousy response from the official.  I'd report that problem every time until something is done about it.  Maybe after it shows up on somebody's PTC help desk log 50 times, they'd try to figure out what is causing that.

Great discussion thank you. 

Fr8engineer Wrote:
-------------------------------------------------------
> With PTC and it's current state of refinement,
> it's probably only a matter of time before the
> request is granted. I believe a year or two ago,
> CSX petitioned the FRA to remove the speed
> enforcement aspect of the cab signal system since
> that is something PTC takes care of. This latest
> incarnation appears to request the removal of the
> entire cab signal system.

The ATC system for freight trains on the RF&P wasn't comprehensive like Amtrak's required locomotive speed limiter. Cab signal drops would require a minimal brake application to be made within whatever time.  CSS ATC always had issues with train handling so the RF&P's solution was just require at least small brake application.  This function could be replaced by PTC w/o loss of capability.

>
> While I am indifferent to the removal of the cab
> signals, there are limitations of the PTC system
> in place that would be nice if they were resolved
> before getting rid of the cab signals entirely.
> For one, if the cab signal improves from an
> approach in the cab to something better, you can
> go with that indication. When outside of cab
> signal territory and the condition of the block
> improves, you still have to go by the last wayside
> (approach) and approach the next signal prepared
> to comply with something red staring you in the
> face. If they get rid of the cab signals on the
> RF&P, no more in-block upgrades from approach to
> something better.

You can read more in depth coverage of the issue here https://position-light.blogspot.com/2021/12/csx-files-to-discontinue-cab-signaling.html

PTC is not a cab signaling system because it avoids all manner of sticky regulatory and technical issues. The jist is that PTC can slow you down, but not speed you up.  If PTC fails, it will fail safe as by rule is cannot give trains a false clear.  

>
> Additionally, there are places where the cab
> signal (and wayside) will upgrade but PTC will
> hold you to restricting until the next block. I
> can't tell you how frustrating it is to have a
> medium clear wayside and cab indication coming out
> of the siding at N Doswell but PTC decides to hold
> you to restricted speed until almost Chandler for
> some reason. I brought this up to an official a
> while back and his exact response was "PTC is
> designed to be more restrictive"....proving once
> again that the people running the show have no
> intention of doing any real "railroading".....
> that's not an answer, sir....

This is why it's good to have NS as a counter-example as they clearly went about integrating it's cab signal and PTC system o the point where they don't need PTC connectivity between interlockings. This is also how ACSES works.  Because coded track circuits are a positive indication of a clear block, an integrated CSS/PTC unit can accept any non-0 cab code  as a valid movement authority.  The case you mention is simply bad PTC implementation, but PTC/CSS integration would make that sort of bad implementation impossible.

Do you know if the RF&P cab signals still drop to Restricting over a Medium Clear or Medium Approach?  I'm also wondering if that has to do with CSX's PTC implementation which does not make use of those omnipresent PTC antenna masts, which might imply use of more limited connectivity.

 



Edited 1 time(s). Last edit at 01/11/22 05:08 by mbrotzman.

I only know the pre-departure cab signal testing procedure that 
 we used at Potomac Yards for RF&P locos headed southward towards 
AccaYard, Richmond.

Our electricians tested the lead unit cab signals for proper functioning
and for penalty applications.

The code tester equipment. ( electrically isolated  test section ---about 500 ft--of single
track, leading to the small lay-up yard for RF&P locos,)... repeated the testing cycle
continuously.  The check-out sequencing started with 'clear', 'then approach', '& restricting'

We 'acknowledged' each more restrictive signal change aspect, and 
made an automatic air brake pressure reduction to forestall a penalty 
application.

The final test was to not take any action as the sequencer ran through its
testing cycle.

When the sequencer went from clear to approach ( or any more restrictive aspect),
The testing technician took NO action.  

The warning cab whistle sounded, I think within 6 seconds, and the penalty STOP sequence
began.  The prime mover went to idle, the PC switch dropped out, The penalty application
disregarded any manipulation of the 'engineer's automatic brake valve ( but he still could apply
the brakes in "Emergency" position).

Under the  control of the penalty apparatus,  the engineer is powerless to negate the automatic
actions that bring the train to a safe, immediate stop.the Automatic air brakes went to a 20-lb
reduction---at a " Service Rate" of reduction, and lapped;  which held for about one minute.  
At the end of that minute, & maintaining the 20-lb reduction, the BP pressure was then reduced
to 'zero', at a 'service application' rate of air depletion.
( 'Emergency' rate of air brakes application was never a part of the 'penalty application' process on RF&P locos).

To recover engineer-control over the brakes, the engineer must place his automatic brake handle valve
in the 'Emergency" position ....and leave it there for the timing reservoir to deplete to zero....which
timing  took 1 full minute.

Any attempt to recover the brakes BEFORE the 1-minute 'wait' ,  reset the timing reservoir to start
a 'new' 1-minute wait period.....after the brake handle was placed back to the 'Emergency' notch,
and left there...  ONLY, after that full,  final minute elapsed, could the engineer take control over the brakes.

Out technicians had to ensure that the complete penalty sequence was tested, prior to departure,
including the test where you attempt to 'recover' the air brakes prematurely, ahead of the final
'one minute' waiting period, with the handle in the 'Emergency' position..

That was what we tested-for before every RF&P freight that departed southward, from PY.

interesringly, the CR diesels' automatic cab signal penalty was only a continuously blowing cab whistle.
No automatic air brake application ever occurred, upon cab signals changing to a more 'restrictive' 
indication.....Those CR units' cab signals were likewise tested prior to all CR departures..

After the tragic Chase, Md. Amtrak wreck, January 1997(?), CR had to apply
automatic train stop equipment on locos before AMTRAK was allowed to accept
CR freights over AMTRAK rails*.  

After the Chase Wreck, CR units, on AMTRAK rails,  had to make automatic penalty brake
applications, & STOP, including  "acknowledging" for the more restrictive signal indication..
as well as engineer-initiated braking & getting the train speeds within the criteria required.

Wes Camp
MM, PY, Retired



( What a 'cluster-copulation' that wreck caused! ...
 It had its roots in the early 1950's, when PRR applied to the ICC to allow
the penalty brake application feature to be omitted on all newly ordered diesel freight
locomotives. PRR maintained that penalty applications on freight trains would
cause more derailments....  ICC acquiesced and allowed the exemption: "No Penalty applications"
on cab Signal equipped, new freight Loco purchases....
That set the stage for the 1987 tragedy.

Interestingly, at every congressionally-approved  re-authorization for Amtak's 
money allocation, Amtrak's re-authorization request letters, every year, since it's inception,
had included Amtrak's request to congress to compel that all Locomotive users, over Amtrak's
rails, must be equipped with automatic train-stop air brakes, tied into the track signals.  

At first, CR ( PRR) was operated by the FRA in the early years, & when Congress inquired what 
would be the impact of requiring 'train-stop' equipment to be retroactively applied to non-equipped 
locos, as requested by Amtrak, FRA maintained such a retrofit requirement would be "too costly"
to make it a requirement....

So, Congress never took action... Congress for decades ignored those Amtrak, annual, repeated
legislative requests and stated  pleas....  Amtrak had been ordered, by congressional legislation,
to accept all CR freight trains over tracks ​owned by AMTRAK.
UNTIL 1987...Soon after, Congress acted on Amtrak's "auto train-stop" requests....)
 



Edited 15 time(s). Last edit at 01/11/22 10:25 by wcamp1472.

Wes Camp--  thank you for your great response to the RF&P cab signal departure testing  at Potomac Yard, regards from the east end of the Shore Line of the old NHRR......

Wes, thank you for your explaination of the RF&P cab signals. I have a question about testing, on the outbound Palmetto from Savannah, the testing used to be done with a wire across the track and a remote in a person's hand. I don't know if anyone was in the cab. Your test description was far more extensive than this.

Sam

DirtyShirt Wrote:
In non-cab signalled territory,
> do the PTC rules allow stopped trains to proceed
> at maximum speed based solely on the PTC display,
> or do they have to operate prepared to stop at the
> next wayside signal regardless of what the PTC
> display shows?   

I'm not entirely sure since I don't run passenger trains, but I know when the commuter trains we run between leave the station, the engineer anounces "DIB" to the crew in the passenger cars at stops where they depart without a wayside signal. I'm not sure if their PTC screen shows a max speed of 40 after stopping in the block or what.

If we stop in a block, sometimes the PTC will transfer to restricted speed, other times it does not. I'm not entirely sure what causes it to drop to a restricted speed fence.

Another obnoxious anomaly on the RF&P with cab signals is if you cross over anywhere, the PTC drops the next block to a restricting until your head end clears the far limits of the interlocking. At AF, this occurs even if you're not taking a diverging route at all. While within the limits of the interlocking, it will show a restricting fence at the next signal.


 

Fr8engineer Wrote:

>
> I'm not entirely sure since I don't run passenger
> trains, but I know when the commuter trains we run
> between leave the station, the engineer anounces
> "DIB" to the crew in the passenger cars at stops
> where they depart without a wayside signal. I'm
> not sure if their PTC screen shows a max speed of
> 40 after stopping in the block or what.

That's the special Delay in Block rule for passenger trains, something I'm surprised would still apply in PTC territory as its purpose is to prevent a crew forgetting they are on Appraoch after a station stop.  It's an FRA regulation that would need to be recinded in a rulemaking process.  The fact that it wasn't been already made exempt in PTC territory is just another example of PTC only making operations slower. BTW, VRE trains on the RF&P would become subject to the delay in block rule if the cab signals are removed.  

>
> If we stop in a block, sometimes the PTC will
> transfer to restricted speed, other times it does
> not. I'm not entirely sure what causes it to drop
> to a restricted speed fence.
>

The system has a option of movement authorities that have a time component.  This is present in wayside signals in that if a train is stopped or slowed enough to meet some definition of "delayed", the block ahead can no longer be considered free of obstructions. CSX didn't seem to install those big PTC antennas so they might only have a small area where trains are in communication and if the movement authority times out while the train is out of contact with a radio base that's tough luck.

> Another obnoxious anomaly on the RF&P with cab
> signals is if you cross over anywhere, the PTC
> drops the next block to a restricting until your
> head end clears the far limits of the
> interlocking. At AF, this occurs even if you're
> not taking a diverging route at all. While within
> the limits of the interlocking, it will show a
> restricting fence at the next signal.

How does the cab signal behave in interlocking limits? Do they still drop to Restricting for medium speed routes? 

>
>
>  

mbrotzman Wrote:
-------------------------------------------------------
  The fact that it wasn't been already
> made exempt in PTC territory is just another
> example of PTC only making operations slower.

Yep. Big time.


> The system has a option of movement authorities
> that have a time component.  This is present in
> wayside signals in that if a train is stopped or
> slowed enough to meet some definition of
> "delayed", the block ahead can no longer be
> considered free of obstructions. CSX didn't seem
> to install those big PTC antennas so they might
> only have a small area where trains are in
> communication and if the movement authority times
> out while the train is out of contact with a radio
> base that's tough luck.

Very. I came in on a good signal, stopping short of a wayside approach. With no breaks in the rail between me and the signal, the PTC drops a restricting fence on me after being stationary for a few minutes. Despite the fact I came in on a good signal, and can see the wayside infront of me...and there's nothing between me and the signal, PTC still does this. Sometimes. Very annoying.

> How does the cab signal behave in interlocking
> limits? Do they still drop to Restricting for
> medium speed routes? 
>
Yellow over green in the cab, but sometimes it flips to restricting for a moment. If it flips for too long, PTC throws up a restricting fence and puts the air down on the train.

Countless instances of PTC (plus cabs) slowing the whole operation down. Working the local, going to cut away from cars on the main...sometimes you have to give a little slack on the pin. The instant you change reverser position, the cab signal will drop to restricting. PTC follows cab signals, and now you've got to run restricted speed for the block just because you had to put slack in for the conductor to be able to pull the pin. Things like that seem like they were never thought of...just "here's your PTC, and you'll like it too!".

mbrotzman Wrote:
-------------------------------------------------------

 The fact that it wasn't been already
> made exempt in PTC territory is just another
> example of PTC only making operations slower. 

The above statement is incorrect.  An additional clause added to the DIB rule eliminating the requirement for speed restrictions in PTC territory has been long-promulgated on many railroads:

GCOR 9.9: Train Delayed Within a Block If a train has entered a block on a proceed indication that does not require restricted speed, and the train stops or its speed is reduced below 10 MPH, the train must:
...
D. PTC When the PTC display indicates the next governing signal will not require a stop, the train may proceed prepared to enter the next block complying with the signal indication governing that block.

Furthermore, it has been claimed previously in this (or a similar) thread that PTC does not provide for in-block upgrades.  This statement is also largely incorrect.  A sentence added to GCOR 9.8 on many railroads effectively recognizes and provides that capability:

GCOR 9.8: Next Governing Signal A train may comply with the next signal's indication when its aspect can be clearly seen and the signal governs the track where movement is occurring or will be made. When the PTC display indicates the next governing signal will not require a stop, the train may proceed prepared to enter the next block complying with the signal indication governing that block. This does not apply when a rule or previous signal indication requires movement at restricted speed.
 

Fr8engineer Wrote:

> Yellow over green in the cab, but sometimes it
> flips to restricting for a moment. If it flips for
> too long, PTC throws up a restricting fence and
> puts the air down on the train.
>

This is a function of (1) the typical lack of cab code on the trailing or inside switch of a crossover and (2) the PTC system being connected to the onboard cab signal system on CSX locomotives operating on the RF&P.

The phenom does not occur on locomotives where the PTC and onboard cab signal systems are not connected.



Edited 1 time(s). Last edit at 01/13/22 10:56 by TractiveEffort.

Those GCOR rules may be employed elsewhere, but here...the MARC trains still have to operate DIB after every stop in PTC territory, and if we pass an approach signal wayside, he have to be prepared to stop at the next signal even if PTC "upgrades" the block.

Additionally...if I enter signaled terrirtory on a restricting (following another train), the cab signal will upgrade as the train in front of me gets further and further away...all the way up to a clear in the cab. PTC remains with the block showing "restricted speed" until the leading wheels get to the next wayside signal even with a clear in the cab.

I believe what you're saying about the switches in the crossover...I think at most interlockings, there is a drop when crossing over. But I don't believe it's at all of them. I try to keep moving.

TractiveEffort Wrote:
-------------------------------------------------------
> mbrotzman Wrote:
> --------------------------------------------------
> -----
>
>  The fact that it wasn't been already
> > made exempt in PTC territory is just another
> > example of PTC only making operations slower. 
>
> The above statement is incorrect.  An additional
> clause added to the DIB rule eliminating the
> requirement for speed restrictions in PTC
> territory has been long-promulgated on many
> railroads:
>
> GCOR 9.9: Train Delayed Within a Block If a train
> has entered a block on a proceed indication that
> does not require restricted speed, and the train
> stops or its speed is reduced below 10 MPH, the
> train must:
> ...
> D. PTC When the PTC display indicates the next
> governing signal will not require a stop, the
> train may proceed prepared to enter the next block
> complying with the signal indication governing
> that block.
>
> Furthermore, it has been claimed previously in
> this (or a similar) thread that PTC does not
> provide for in-block upgrades.  This statement is
> also largely incorrect.  A sentence added to GCOR
> 9.8 on many railroads effectively recognizes and
> provides that capability:
>
> GCOR 9.8: Next Governing Signal A train may comply
> with the next signal's indication when its aspect
> can be clearly seen and the signal governs the
> track where movement is occurring or will be made.
> When the PTC display indicates the next governing
> signal will not require a stop, the train may
> proceed prepared to enter the next block complying
> with the signal indication governing that block.
> This does not apply when a rule or previous signal
> indication requires movement at restricted speed.
>  

Does ETMS inform one of the next signal indication or only that the next signal is no longer Restricted speed or stop? The phrase "complying with the signal indication governing that block" implies one would need to be aware of the signal indication of the next block, as in being close enough to see it. When I was looking into this in 2019 for a potential cybersecurity study of PTC systems the GCOR rules at the time took the form of "follow all the normal rules and PTC will stop you if necessary.  That approach would allow railroads to take the position that any technical vulnerabilities in the PTC system could not be a safety risk because PTC was not conveying safety critical information.

> This is a function of (1) the typical lack of cab
> code on the trailing or inside switch of a
> crossover and (2) the PTC system being connected
> to the onboard cab signal system on CSX
> locomotives operating on the RF&P.
>
> The phenom does not occur on locomotives where the
> PTC and onboard cab signal systems are not
> connected.

Enforcing restricted speed is part of the PTC requirement.  On an ATC equipped passenger train one has to put the brake into suppression.  A PTC system should see a lRestricting cab the same way, but ideally require a penalty applications.  I'm pretty sure whatever NS is using on its segments without wayside signals has managed to avoid this problem.  


Fr8engineer Wrote:

> Additionally...if I enter signaled terrirtory on a
> restricting (following another train), the cab
> signal will upgrade as the train in front of me
> gets further and further away...all the way up to
> a clear in the cab. PTC remains with the block
> showing "restricted speed" until the leading
> wheels get to the next wayside signal even with a
> clear in the cab.

It would be interesting to see if this problem exists on NS and for MARC trains on the NEC, but my suspicion is that they do not.  As I've mentioned before the tell is that on its cab signal territory NS does not have PTC antennas at any intermediate signal location, but does have them at interlockings.  The implication is that between interlockings NS is relying on the cab code for movement authority since there is no alternate PTC data coverage.  

CSX doesn't seem to install those PTC antennas at interlockings or automatic signal locations so they might have a different strategy for maintaining a data link and requires different in-cab behavior of the system.



Edited 2 time(s). Last edit at 01/14/22 07:37 by mbrotzman.