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Discussion relating to the operations of MTA MetroNorth Railroad including west of Hudson operations and discussion of CtDOT sponsored rail operations such as Shore Line East and the Springfield to New Haven Hartford Line

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 #1235396  by Jersey_Mike
 
Head-end View wrote:The mid-day news today announced that Metro-North has reduced the cab-signal code on the approach to the Spuyten Duyvil curve. My question is: if it was so simple to do, that they did it in just a few days, why wasn't it set up this way originally to enforce the radical speed reduction at this location?
I mentioned this before, but since Metro-North decided to eliminate wayside signals in the 1980's, relying on the cab signals for MAS warnings would make it impossible for the Engineer to tell if a particular code drop was due to congestion or the curve. Each situation involves a different method of handling the train (preparing to stop vs preparing to slow down) and it would be worthwhile to eliminate the confusion. Amtrak did not suffer from this problem when it installed the code change points on the NEC because the wayside signals continue to display their normal compliment of indications which reflect the true state of the track ahead.
 #1235400  by JimBoylan
 
Is it correct that the only Metro North cab signal aspect with a 30 m.p.h. peed limit also indicates "prepared to stop at the next signal"? That might slow the train to much less than 30 m.p.h. before it has passed the sharp curve.
 #1235445  by Clean Cab
 
Fishrrman wrote:CleanCab writes:
[[ The restriction is for trains that encounter a 20 MPH change in speed. A northbound Hudson Line train would not encounter that. ]]

Huh?

What about the downward speed transition from BN curve to the cut and curves between Marble Hill and CP 12?
The restriction has to be more than 20 MPH.
 #1235470  by Pensey GG1
 
Fishrrman wrote:Pensey GG1 writes:
[[ That's why we need full PTC. Then we don't really have to care. ]]

If you want to see train operations slow down to a point of near-standstill in high-density areas (such as Metro-North, NJ Rail, etc.), just wait until PTC is in full-force.

You ain't seen nuthin' yet!

Can you imagine EVERY train on MN at Stamford or MO (CP5) during rush hour having to go through what an Amtrak train approaching a Stop Signal in ACSES territory at, say, Guilford has to do?
Yes, I can imagine it. Amtrak already uses ACSES on parts of the main line through NJ, as well as in MARC territory, as well as SLE and MBTA's busy Providence Line, and it all seems to work just fine. SLE would rarely get a stop signal at Guilford, and if it does, it would have to wait for a passing train afterwards anyways, so a slowdown doesn't really matter. If there's that much of a problem with handling trains under PTC through a busy section, then slow them all down to 15 or 25 or whatever the station/yard areas get, and let them run without, but it's far better to set up a clear path through the interlocking before they get there, and run them right through without bad signals.
 #1235492  by Noel Weaver
 
spidey3 wrote:
Trainer wrote:
spidey3 wrote:
ryanov wrote: [...]



My point is merely that there is a double standard. Can you imagine the hue and cry if FHA proposed requiring cars to be physically limited to 55 MPH?
This actually happened in the early 1980's on the New Haven Line when the M-2's which were built with hollow axles developed a habit of wheels actually falling off at speed several times, one landed in a backyard somewhere around Southport for example. The FRA stepped in and put in effect an immediate wheel and axle inspection at two locations, New Rochelle and I believe just east of South Norwalk and every train had to stop for inspection. How did this get corrected? The railroad retrofitted every car with solid axles. Why hollow axles in the first place? To meet the weight restrictions on the viaduct leading to the Park Avenue Tunnel. This restriction was lifted along with others after the viaduct was rehabilited around this time. I hate to think what the safety standards would be on some of the commuter railroads if the FRA was not deeply involved with overseeing them. I will probably add to this down the road but this is enough for right now.
Noel Weaver
 #1235495  by RearOfSignal
 
JimBoylan wrote:Is it correct that the only Metro North cab signal aspect with a 30 m.p.h. peed limit also indicates "prepared to stop at the next signal"? That might slow the train to much less than 30 m.p.h. before it has passed the sharp curve.
That is not true.
 #1235545  by Head-end View
 
Seems like LIRR has the best of both worlds in signaling. They have cab-speed aspects of 80, 70, 60, 40, 30, 15 on the M-7's. And still use "standard" wayside signal aspects, though only at home signals in many areas. Supposedly some years back MTA wanted to convert LIRR to Metro-North style wayside signals, but LIRR's operating depts. stood their ground and insisted on keeping regular signal aspects.

BTW, SEPTA in Philadelphia also converted to something similar to M-N's signals, and their engineers hate it for the very reasons cited above. That you don't know whether the cab-speed reduction is for congestion ahead or track-routing at next interlocking.
 #1235567  by Clean Cab
 
The M8's ADU (Aspect Display Unit) have basically two sets of aspects that combined the Amtrak ACSES and MN systems. It currently only uses the four MN aspects ("N"=MAS, "L"=45 MPH, "M"=30 MPH & "R"=Restricted Speed) and the others (80, 60 & "S")will be used when the PTC system is operational.
 #1235613  by Jersey_Mike
 
Clean Cab wrote:The M8's ADU (Aspect Display Unit) have basically two sets of aspects that combined the Amtrak ACSES and MN systems. It currently only uses the four MN aspects ("N"=MAS, "L"=45 MPH, "M"=30 MPH & "R"=Restricted Speed) and the others (80, 60 & "S")will be used when the PTC system is operational.
80 and 60 (and 100 and 150 for that matter) have nothing to do with the PTC system. Those are the additional cab signal codes used by Amtrak and NJT for high speed turnouts and the high density signaling system used between Newark and Penn Station. MNRR currently uses Clear cabs for 80mph high speed turnouts as the turnout speed is higher than the MAS where implemented.
Head-end View wrote: BTW, SEPTA in Philadelphia also converted to something similar to M-N's signals, and their engineers hate it for the very reasons cited above. That you don't know whether the cab-speed reduction is for congestion ahead or track-routing at next interlocking.
SEPTA's move was actually intended to make the signaling transit style with lunar and flashing lunar indications, but someone complained and got it changed to the Cab Speed thing. They were supposed to add a new indication for diverging movements but never did. They did add in a bunch of speed control stuff that MNRR also wisely avoided and it is just absolutely brain dead.
 #1235621  by Clean Cab
 
Jersey_Mike wrote:
Clean Cab wrote:The M8's ADU (Aspect Display Unit) have basically two sets of aspects that combined the Amtrak ACSES and MN systems. It currently only uses the four MN aspects ("N"=MAS, "L"=45 MPH, "M"=30 MPH & "R"=Restricted Speed) and the others (80, 60 & "S")will be used when the PTC system is operational.
80 and 60 (and 100 and 150 for that matter) have nothing to do with the PTC system. Those are the additional cab signal codes used by Amtrak and NJT for high speed turnouts and the high density signaling system used between Newark and Penn Station. MNRR currently uses Clear cabs for 80mph high speed turnouts as the turnout speed is higher than the MAS where implemented.
Head-end View wrote: BTW, SEPTA in Philadelphia also converted to something similar to M-N's signals, and their engineers hate it for the very reasons cited above. That you don't know whether the cab-speed reduction is for congestion ahead or track-routing at next interlocking.
SEPTA's move was actually intended to make the signaling transit style with lunar and flashing lunar indications, but someone complained and got it changed to the Cab Speed thing. They were supposed to add a new indication for diverging movements but never did. They did add in a bunch of speed control stuff that MNRR also wisely avoided and it is just absolutely brain dead.

The additional aspects on an M8 ADU are ACSES compatible indications for when (if) they ever operate on Amtrak's Shore line. And they will indeed be part of MN's upgraded PTC system. For the time being MN uses "N" for their high speed turnouts. I ran trains for MN for 22 years and was part of the M8 design project, so I think I have a slight edge on this topic.
 #1235641  by RearOfSignal
 
MNR can implement the additional aspects without upgrading to PTC, but the vast majority of the fleet is not compatible for such additional aspects. The additional aspects are not the same thing as what the FRA considers PTC to be in its entirety.
 #1235646  by Clean Cab
 
The added aspects will be used for high speed crossovers that are currently in use such as CP 119* (Scarsdale), CP 121** (Hartsdale), CP 240* (South Norwalk), CP 235** (Stamford), CP 217** (East Shell) and a new crossover at CP 266* (Woodmont) that goes from track 3 to track 1 westbound that currently can only display "L" (45 MPH). The upgrading of the signal system will be part of the PTC compliance.

*60 MPH

**75 MPH
 #1235662  by Jersey_Mike
 
Clean Cab wrote:The added aspects will be used for high speed crossovers that are currently in use such as CP 119* (Scarsdale), CP 121** (Hartsdale), CP 240* (South Norwalk), CP 235** (Stamford), CP 217** (East Shell) and a new crossover at CP 266* (Woodmont) that goes from track 3 to track 1 westbound that currently can only display "L" (45 MPH). The upgrading of the signal system will be part of the PTC compliance.

*60 MPH

**75 MPH
It's super that MNRR is doing that, but the extra CSS codes are neither necessary for PTC compliance nor are they a part of the ACSES system. ACSES v1 would enforce the existing HST speeds as part of MAS enforcement and v2 can enforce route speeds through interlockings even if the cab signals are non-functional.

The extra CSS codes were first developed for Amtrak use around 15 years ago for high density signaling, high speed trains and high speed turnouts. They use a combination of 250Hz overlay codes to remain compatible with the existing 4 indication 100Hz system and also borrowed the 270ppm 60 code from the LIRR ASC.

The only situation where the 60 and 80 codes would be needed from a PTC point of view is a high density signaling setup as ACSES does not enforce train separation.
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