North East Corridor (NEC) speeds, new stations and state of repair

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The whole point of constant tension is to eliminate the effect of temperature on sag.
Mr. Harris. Isn't constant tension just going to reduce sag? Granted sag will be much less but the Catenary formula still means that there will be some sag between each hanger from the traveler. The math is complicated but variable tension PRR style allows much more sag between each hanger. Of course, the maximum temperature variations will effect the coefficient of expansion of the specific wire metal formula per degree of temp rise of the wire. That number may not be linear.

https://railroad.net/field-guide-to-amtrak-catenary-t26913.html

Everything about CAT construction mainly constant tension. Remember for each increase of MAX authorized speed increase sag has to be reduced. IMO it appears that number of PANs on a train may also effect snags with CAT that may operate with only one pan. Note: the AX-2 test videos appear to mostly only use one PAN?
 
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The whole point of constant tension is to eliminate the effect of temperature on sag.
Mr. Harris. Isn't constant tension just going to reduce sag? Granted sag will be much less but the Catenary formula still means that there will be some sag between each hanger from the traveler. The math is complicated but variable tension PRR style allows much more sag between each hanger. Of course, the maximum temperature variations will effect the coefficient of expansion of the specific wire metal formula per degree of temp rise of the wire. That number may not be linear.

https://railroad.net/field-guide-to-amtrak-catenary-t26913.html

Everything about CAT construction mainly constant tension. Remember for each increase of MAX authorized speed increase sag has to be reduced. IMO it appears that number of PANs on a train may also effect snags with CAT that may operate with only one pan. Note: the AX-2 test videos appear to mostly only use one PAN?
Constant tension does not necessarily reduce sag, it just makes it constant regardless of temperature. With fixed terminals the wire tension gets lower with increased temperature, increasing sag and the bounce of the wire from the pantograph pressure. With lower temperatures, the tension in the wire increases, reducing sag and the bounce of the wire from the pantograph pressure. Like many things mechanical, it is like Goldilocks and the three bears, not too hot (stiff), not too cold (slack) but just right.

Actually, what I said was only a partial answer. Constant tension is also to make the bouncing of the cantenary with the passing of the pantographs constant regardless of temperature. Tension also affects/determines the rate of propagation of the wave in the wire resulting from the pantograph load on the wire. Think of how the tone of the wire on a stringed instrument varies with the tension in the wire. There are lengthy studies, and likely books written on the subjects of preferred bounce, wave propagation rates and other factors with different speeds and pantograph pressures. My knowledge of what these should be is essentially nil. By the way, I think the coefficient of thermal expansion for the temperature range and metals involved is essentially constant. I could confirm this from a book I have called the Metals Handbook, Desk Edition which is somewhere over 2 inches thick that would tell me way more than needed to answer these questions. Unfortunately, the book is at my house and I am not.
 
Why so many catenary problems in this area lately? I've been riding the Northeast Corridor since about 1970, when the electric trains were mainly GG1's and MP54's. The catenary was probably the same as it had been for quite a few decades, and there were occasional problems, but I don't remember problems on this scale until the past few years. Even if some NJ Transit pantographs are contributing to the problem, they aren't on new equipment, right? Mostly ALP-46's, the DM's, and the same old Arrows, all of which have been running for some years?
 
Why so many catenary problems in this area lately? I've been riding the Northeast Corridor since about 1970, when the electric trains were mainly GG1's and MP54's. The catenary was probably the same as it had been for quite a few decades, and there were occasional problems, but I don't remember problems on this scale until the past few years. Even if some NJ Transit pantographs are contributing to the problem, they aren't on new equipment, right? Mostly ALP-46's, the DM's, and the same old Arrows, all of which have been running for some years?
Good question. Could one possible reason be a reduced maintenance of way force, compared to back then?🤔
If so, it could mean more frequent incidents, or a longer time to repair any…

Also, isn’t there more rail traffic compared to back then?
 
Riding since 1970? Someone posted that then pollution was very bad. Is it possible since the days are much clearer today that wire temperatures are higher in the direct sunlight? If so, that would mean PRR CAT would sag more today than in the 1970s? Add constant tension now?? Unfortunately, Portal bridge replacement (2-1/2 miles), Sawtooth bridge (1-1/2 / miles ?), Dock bridge, Secaucus, various track relocations. All those projects means replacing with constant tension NYP - Newark Penn Station does not make sense. Only solution may be reduced speeds thast will gum up the schedules.?
 
Riding since 1970? Someone posted that then pollution was very bad. Is it possible since the days are much clearer today that wire temperatures are higher in the direct sunlight? If so, that would mean PRR CAT would sag more today than in the 1970s? Add constant tension now?? Unfortunately, Portal bridge replacement (2-1/2 miles), Sawtooth bridge (1-1/2 / miles ?), Dock bridge, Secaucus, various track relocations. All those projects means replacing with constant tension NYP - Newark Penn Station does not make sense. Only solution may be reduced speeds thast will gum up the schedules.?
The other solution is to be more diligent about de-stressing the catenary based on season and temperature forecasts. This is done with both non-constant tension catenary (yes there are miles of it remaining where original DC electrification was changed to AC) and long welded rails, in India. Somehow that is apparently not done here, perhaps in homage to labor cost.
 
Maybe there will be some tracks not to be moved that can get constant tension? There is no excuse for Constant tension Newark Penn and south not to be installed. Complete the highest speed sections first. As understood on multi track sections the inside tracks are done first then go to outward tracks.

Now up grading the Amtrak electrical system it is on its own as NJT is all 60 hZ except for partial 25 hZ coast line which is supplied by Amtrak. All partial upgrades for 25 hZ need to be compatible for future upgrades to 60 hZ. It is obvious that Amtrak does not have enough backup electrical circuity to prevent single point failures from cutting power to its CAT.
 
Maybe there will be some tracks not to be moved that can get constant tension? There is no excuse for Constant tension Newark Penn and south not to be installed. Complete the highest speed sections first. As understood on multi track sections the inside tracks are done first then go to outward tracks.

Now up grading the Amtrak electrical system it is on its own as NJT is all 60 hZ except for partial 25 hZ coast line which is supplied by Amtrak. All partial upgrades for 25 hZ need to be compatible for future upgrades to 60 hZ. It is obvious that Amtrak does not have enough backup electrical circuity to prevent single point failures from cutting power to its CAT.
According to the NEC Commission Projects database covering now till 2034, there are no plans to either install further constant tension catenary east of County (Jersey Avenue) to New York Penn Station, nor change over any segment from 25Hz to 60 Hz. There are projects to upgrade substations and increase power capacity.

There is also a project to substantially replace all catenary structure between New Brunswick and Newark Penn Station (exclusive) with new fixed termination catenary using SAP (Steady Assembly Pipe) attachment replacing current attachments. You can see SAP attachments in use in the non-constant tension catenary between County (Jersey Avenue) and Trenton (Fair).

Further south in the Mid Atlantic North Region there is a lot of catenary structure replacement and almost across the board SAP installation, but no plans for constant tension catenary as far as funding goes.
 
Now up grading the Amtrak electrical system it is on its own as NJT is all 60 hZ except for partial 25 hZ coast line which is supplied by Amtrak. All partial upgrades for 25 hZ need to be compatible for future upgrades to 60 hZ. It is obvious that Amtrak does not have enough backup electrical circuity to prevent single point failures from cutting power to its CAT.
I assume by "NJT is all 60 Hz" you mean lines that are exclusively NJT such as the former Lackawanna out of Hoboken.

There is really no reason to convert from 25 Hz to 60 Hz and such a change would require a massive replacement of fairly modern solid state frequency converter substations plus the Susquehanna River dam generators that provide 25 Hz directly. Consider that in Europe Germany and Switzerland (and Austria?) still use 16.7 Hz and have no plans to convert from the lower frequency.
 
As for the catenary issues, it seems like Amtrak waits until they fail before doing anything to fix them. They need to step up preventative maintenance work.
As for high speed rail, I don't believe we need much more than we already have. In many cases the train is already faster or comparable to air travel. For instance the Acela from MET to WAS is under 3 hours and it leaves you off right in the city,
If we took air travel, we would have to allow 3 hours travel time to EWR, ( finding parking/security lines can be long) then take a 1 hour flight and a 30 minute ride from Dulles to center city plus time to access luggage. With the Acela the fare is less expensive, the seats are larger, luggage is with you, coffee, food,WiFi available and the daily parking rate at Metropark is. $10. Its a 30 minute car ride to the station there but I'll add that in.
For us the Acela is approximately a 4 hour trip whereas air travel could run 5 hours or more but do we really want to be stuffed in to a plane like a sausage? We'll take the train for the better experience.
 
I don't think "Amtrak waits for the overhead electrification to fail" is accurate, otherwise we'd see failures more often outside the small area where NJT is having trouble.

I won't go as far as saying Amtrak is perfectly on top of maintenance everywhere, but there's a huge difference between that and only doing remedial work.
 
As for the catenary issues, it seems like Amtrak waits until they fail before doing anything to fix them. They need to step up preventative maintenance work.
As for high speed rail, I don't believe we need much more than we already have. In many cases the train is already faster or comparable to air travel. For instance the Acela from MET to WAS is under 3 hours and it leaves you off right in the city,
If we took air travel, we would have to allow 3 hours travel time to EWR, ( finding parking/security lines can be long) then take a 1 hour flight and a 30 minute ride from Dulles to center city plus time to access luggage. With the Acela the fare is less expensive, the seats are larger, luggage is with you, coffee, food,WiFi available and the daily parking rate at Metropark is. $10. Its a 30 minute car ride to the station there but I'll add that in.
For us the Acela is approximately a 4 hour trip whereas air travel could run 5 hours or more but do we really want to be stuffed in to a plane like a sausage? We'll take the train for the better experience.
And it should be pointed out that riding the NEC is definitely faster than driving, and that includes going all the way between Washington and Boston. And, of course, it's much less of a hassle than driving on I-95.
 
According to the NEC Commission Projects database covering now till 2034, there are no plans to either install further constant tension catenary east of County (Jersey Avenue) to New York Penn Station, nor change over any segment from 25Hz to 60 Hz. There are projects to upgrade substations and increase power capacity.

There is also a project to substantially replace all catenary structure between New Brunswick and Newark Penn Station (exclusive) with new fixed termination catenary using SAP (Steady Assembly Pipe) attachment replacing current attachments. You can see SAP attachments in use in the non-constant tension catenary between County (Jersey Avenue) and Trenton (Fair).

Further south in the Mid Atlantic North Region there is a lot of catenary structure replacement and almost across the board SAP installation, but no plans for constant tension catenary as far as funding goes.
IMO the only item SAP will do is greatly reduce the occurrences of multi track pull downs when a snag happens. Cannot visualize SAP preventing snags.
 
IMO the only item SAP will do is greatly reduce the occurrences of multi track pull downs when a snag happens. Cannot visualize SAP preventing snags.
Amtrak's claim is that SAP catenary is good for 145mph, above that requires constant tension. The only way to reduce sag in summer in non-constant tension catenary is to actively increase tension in the cables before the start of the season and then reverse the process near the end of the season, synchronizing as best as one can with forecasts, as is done in many places with fixed mount catenary in large temperature variation zones.

However, the rather frequent catenary snags in the tunnels under the river is arguably not because of temperature variation related expansion/contraction.
 
IMO there are many locations that it is not financially responsible to install constant tension CAT yet. A prime example is NYP - Newark Penn. Amtrak has restoration of North River tunnel bores, new Gateway tunnel bores, Secaucus, new Portal North Bridge. future South Portal Bridge, new replacement Sawtooth Bridge, Harrison PATH track relocation and new 4th main track, Dock bridge rehab, Newark Penn station rehab, possible PATH extension toward Newark airport. All these projects will mean track relocations and new tracks. So, we probably cannot expect constant tension for this section until 2035 - 2040 as the projects are completed?

South of Newark airport there are many locations that track speeds that have potential to have increases of MAX speeds. Examples such as the 70 MPH limit just south, Elizabeth curve, Frankford junction and south to Zoo, Now can constant tension be installed between these points. Have no idea how hard to install transition between the 2 systems. When constant tension is installed, provisions have to be made for higher wire temps than now.
 
South of Newark airport there are many locations that track speeds that have potential to have increases of MAX speeds. Examples such as the 70 MPH limit just south, Elizabeth curve, Frankford junction and south to Zoo, Now can constant tension be installed between these points. Have no idea how hard to install transition between the 2 systems. When constant tension is installed, provisions have to be made for higher wire temps than now.
South of Elizabeth Curve to just short of Metropark is 125mph on 2 and 3 tracks AFAIR. No pressing need for constant tension since there is no plan to increase speed there beyond 135 at most. According to the Tier 1 EIS the mucho dinero HSR line is supposed to be underground here with 200mph speed, if ever built
 
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IMO the only item SAP will do is greatly reduce the occurrences of multi track pull downs when a snag happens.
I do not think this is a true statement.

There is also a project to substantially replace all catenary structure between New Brunswick and Newark Penn Station (exclusive) with new fixed termination catenary using SAP (Steady Assembly Pipe) attachment replacing current attachments. You can see SAP attachments in use in the non-constant tension catenary between County (Jersey Avenue) and Trenton (Fair).

Further south in the Mid Atlantic North Region there is a lot of catenary structure replacement and almost across the board SAP installation, but no plans for constant tension catenary as far as funding goes.
To install new fixed termination catenary in this current day strikes me as being like buying a Model T Ford today when you replace your car.
 
To install new fixed termination catenary in this current day strikes me as being like buying a Model T Ford today when you replace your car.
But if replacing your car with a newer model meant being without it for months at a time while the new car was being assembled, then you might elect to just repair the old car with new parts. I imagine installing constant tension would be very disruptive since I don't see how you could replace it on one track at a time and still maintain service on other tracks based on how it is designed. Maybe the SAP will be easier to replace with CT in the future.
 
To install new fixed termination catenary in this current day strikes me as being like buying a Model T Ford today when you replace your car.
With the state of funding and backlog critical work that needs attention on the NEC, I just thank the stars that they are actually contemplating replacing rotting structures. I do not particularly bemoan the lack of constant tension since the money needed for that needs to be dug away from some other thing like bridge ready to fall off or some such. :D

But given enough resources the preference should be to upgrade to constant tension as was done by ConnDOT. As a counterexample, when the Mumbai and Kolkata area suburban DC electrification was converted to AC by Indian Railways, the catenary, which was fixed termination, was left as is, with only changes made limited to insulators and feed network. It is only now after multiple decades that they are selectively replacing the entire catenary system using completely new hardware and removing all old structures while at it. But then, these days their budget is flush with cash enabling them to electrify/re-electrify at the rate of 15km per day, something quite different from the situation in the US.

I was merely looking through the project list maintained by the NEC Commission and reporting on what is planned and funded.

I assume by "NJT is all 60 Hz" you mean lines that are exclusively NJT such as the former Lackawanna out of Hoboken.

There is really no reason to convert from 25 Hz to 60 Hz and such a change would require a massive replacement of fairly modern solid state frequency converter substations plus the Susquehanna River dam generators that provide 25 Hz directly. Consider that in Europe Germany and Switzerland (and Austria?) still use 16.7 Hz and have no plans to convert from the lower frequency.
NJT has actually never converted anything from 25Hz to 60Hz. The Morris and Essex re-electrification was from DC to 25kV 60Hz. The other 25kV 60Hz segment is from Matawan (exclusive) to Long Branch (inclusive) on the North Jersey Coast Line. This segment, unlike the M&E is constant tension catenary. The 25Hz electrification from CP Union (Rahway) to Matawan (inclusive) on the North Jersey Coast Line is legacy PRR electrification and is fed power from the Rahway end from the now Amtrak 25Hz power network.

I don't think "Amtrak waits for the overhead electrification to fail" is accurate, otherwise we'd see failures more often outside the small area where NJT is having trouble.

I won't go as far as saying Amtrak is perfectly on top of maintenance everywhere, but there's a huge difference between that and only doing remedial work.
I fully agree with you. I also suspect that there is more to it than catenary structure issues. NJT is famous for skimping on maintenance of their equipment which in the past has led even to a derailment.
 
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South of Elizabeth Curve to just short of Metropark is 125mph on 2 and 3 tracks AFAIR. No pressing need for constant tension since there is no plan to increase speed there. According to the Tier 1 EIS the mucho dinero HSR line is supposed to be underground here with 200mph speed, if ever built
Correct. From Elmora which is just west of the Elizabeth S curve to Union (Rahway) is 125 on 2 and 3.
 
But if replacing your car with a newer model meant being without it for months at a time while the new car was being assembled, then you might elect to just repair the old car with new parts. I imagine installing constant tension would be very disruptive since I don't see how you could replace it on one track at a time and still maintain service on other tracks based on how it is designed. Maybe the SAP will be easier to replace with CT in the future.
The conversion to constant tension between Midway (Monmouth Junction) and just short of Hamilton in NJ was effectively done one track at a time, incidentally at the same time complete renewal of the same track was also done one track at a time. Same thing was done on all of MNRR on the New Haven Line. So not only can it be done, but it is actually common practice.

Having SAP or not has little to do with ease or not of replacing with constant tension catenary. Constant tension requires either hinged mounts or mounts with rollers for the messenger allowing the catenary to move longitudinally. The SAP mounts are fixed. So they will all need to be changed out anyway, just like the non SAP ones would too.
 
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Article yesterday from the New York Magazine's subsidiary Curbed highly critical of the state of electrification on the NEC:
https://www.curbed.com/article/amtrak-northeast-corridor-power-supply-catenary-failing.html
At least ten times in the past two months, tens of thousands of people had their days ruined by a failure of one of the most fundamental pieces of infrastructure in America: the electrical system that powers Amtrak and New Jersey Transit trains on the Northeast Corridor. Stranded riders were furious. Amtrak and New Jersey pointed fingers. The whole region was left wondering how this could happen to the transportation backbone of the densest part of the country. How could the one piece of passenger rail in this country that more or less, kind of, approximately, works as a business — the closest thing we have to a modern electric European railway — break down so often?

The answer is likely a toxic combination of deferred maintenance on a fraying and ancient power supply. The catenary — the overhead arrangement of poles and wires that supplies electricity to moving trains — on the Northeast Corridor was inherited from the Pennsylvania Railroad, which went out of business in 1970. Most of the catenary system is about 80 years old. Fifty years ago, federal officials were already saying that they needed to replace it wholesale with a modern setup, only to shelve the program amid budget overruns. Attempts at incremental upgrades, in turn, have been beset by mismanagement and poor accounting at Amtrak. To make things all the more maddening, the decrepit power system is also one of the biggest reasons that Amtrak’s bullet train, the Acela, is so slow.

Amtrak’s own regulatory filing from last year states that not one inch of the overhead wiring between Washington, D.C., and New York’s Pennsylvania Station — zero percent — is in a state of good repair. On a scale of zero to five, with zero signifying that the system is so decrepit that it cannot function, Amtrak rates the electrical system a 1. In that document, called the Infrastructure Asset Line Appendices, Amtrak’s Electric Traction unit, which manages the catenary, acknowledges that it’s getting worse: Electric Traction “acknowledges that preventive maintenance activities are not consistently completed due to limited resource availability and a need to provide ET staff to support other asset classes … or capital projects. This has resulted in a growing maintenance backlog, which is becoming a major priority.” That backlog, which measured less than $100 million in 2018 according to Amtrak charts, now sits at an estimated $829 million. Another $2.9 billion is needed to replace or repair poles and other structures that hold the wires. Amtrak’s figures say that each of the three units in its Electric Traction division is understaffed, and the group that keeps up the wiring in the mid-Atlantic states is in the worst shape. (A spokesman for the railroad said it has has hired more than 300 trainees across the division.)

“They’ve been reduced to a patch type of program — that’s what they say here,” said Joe Clift, a transit advocate who previously served as Long Island Rail Road’s chief of planning, when reviewing the documents. “If they have a reactive approach to maintenance, then you know two things: that they’re spending the least amount in the near term, and at the same time, guaranteeing service outages that really screw the customer.” He added: “Because it’s the trunk line of the New Jersey system, everybody gets hit.”

That lack of planning and maintenance, said a source who is knowledgeable about the extent of the problem, extends to Penn Station, where power went out several times over the past several weeks. Amtrak is backing an unfunded $16 billion program to build a giant new extension of the rail hub immediately to the south of the existing station but has no plans to upgrade what’s there now. “You’re going to do this $16 billion thing and just leave all these shitty tracks and signals and catenary in place,” said a person familiar with the plans. “As far as I know, nothing has changed with that.”

The wiring that Amtrak and New Jersey Transit rely on is a bespoke system that was built by the Pennsylvania Railroad nearly a century ago, then run by its successor Penn Central, then handed over to the public after the railroad went broke and was nationalized. In the 1970s, the federal government plotted an aggressive set of upgrades meant to revive train service along the Northeast Corridor by substantially increasing its speed and reliability. They identified several major problems, including — according to a report completed in 1975 that I obtained as part of a fellowship investigating rail modernization at New York University — that, unlike those on high-speed rail systems elsewhere, the wires are not constantly tensioned. Instead they just hang.
 
"not one inch of the overhead wiring between Washington, D.C., and New York’s Pennsylvania Station — zero percent — is in a state of good repair." Even the parts that have been upgraded with constant-tension catenary? Also, it addressed only the line between Washington and New York, not addressing the catenary between New Haven and Boston that is less than 25 years old.
 
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