FRA Tier II speed upgrade: 150mph to 160mph

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John Bobinyec said:
jis said:
But you seemed to be suggesting that there is a big incremental cost involved in going to 160 from 150, possibly inadvertently so.
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I'm sorry, I thought the FRA was requiring quite a bit more in enhancements which would make that kind of thing infeasible.
jb
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Mostly the incremental cost was in getting another safety case done, one that applied to all proposed segments for the higher speed on NEC both north and south. Actually there would still be greater length of track with the higher speed in the north than in the south. That is even more so with the botched project execution in NJ. There never was any additional money allocated for that change since none was deemed necessary.
 
I've got to admit I'm with Seaboard92 here. Given the limited funds available and the State of Not Good Repair of the NEC, I'd focus the funds on:

1) projects addressing the areas that are at risk of being removed from service (Gateway including Portal Bridge, Baltimore tunnels, Susquehanna bridge);

2) projects aimed at boosting the limit in the lowest speed areas. You'd get a lot more utility for a lot more trains if you could e.g. raise the limit through Frankford Junction by 10mph for all trains than any of the stretches listed above for Acela only.
 
RPC said:
I've got to admit I'm with Seaboard92 here. Given the limited funds available and the State of Not Good Repair of the NEC, I'd focus the funds on:

1) projects addressing the areas that are at risk of being removed from service (Gateway including Portal Bridge, Baltimore tunnels, Susquehanna bridge);

2) projects aimed at boosting the limit in the lowest speed areas. You'd get a lot more utility for a lot more trains if you could e.g. raise the limit through Frankford Junction by 10mph for all trains than any of the stretches listed above for Acela only.
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None of these funds were allocated at a time when anything could have been allocated to Gateway. It was soon after the collapse of ARC.

Who says that funds are not allocated to raising speeds at lower speed areas? Any idea what the speed limits was on the Elizabeth curve five years back? Any idea what it is now? Just to pick a random example. All NEC projects are somewhat opportunistic in nature as in having funds lined up when opportunities materialize for making significant improvements. When this round of funding happened neither Gateway nor Portal were in a state where they could be meaningfully funded to achieve anything within the limits of the time horizon of the funding. These funds were partly time limited so either the money could have been rescinded and sent back to the general coffers or used for something useful. The money became available because the Florida Governor did not want it back then. It certainly seemed like a good idea to make opportunistic use of it to improve reliability and state of good repair of the track, electrification and signaling system in NJ. Apparently some people here disagree because they are fixated on 150/160mph for Acelas. Frankly I expect people here to be a little better informed about the content of each project instead of endlessly parroting newspaper headlines. They would be even if they bothered to go back and read discussions here and on other boards, but apparently not.
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According to Thirdrail 80 for Acelas and 60something for Amfleet AFAIR. Frankly I had expected it to go upto sixty-something. I was floored when Thirdrail informed me that it was going up to something like 80 for Acelas. Apparently the tilt mechanism keeps the lateral forces on passengers within comfort limits even at that speed. To get there the curve spirals had to be modified and of course ACSES civil speed (PSR) enforcement (using track mounted transponders) had to be used instead of signal speed enforcement.

Incidentally, before an Amtrak jockey tried to run an AEM-7+Amfleet consist through it at 100mph almost derailing the train and basically destroying the track, the speed limit used to be 55mph. It was reduced to something that was enforceable using signal speed limits after that. So it came down to something like 40-45, whatever the approach medium enforceable speed is (I forget). It was raised after ACSES was put into operation and that too only on tracks 2 and 3 AFAIR.
 
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If north of Frankford - North PHL was straightened to allow 160 that would save more time than all the other incremental speeds proposed. Said 160 as new CAT would need to be installed over new routing.
 
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I think Seabord92 makes some very valid points, but some might argue that any speed upgrade is worth it, as they are maddeningly few and far between in this country for various reasons even though the potential is largely there. If 125 or 135 is good enough, why not lower the sections north of New Haven to save on maintenance costs? It could be seen as a slippery slope.

There is also the PR aspect of it for Amtrak, like there was in 2000 for the original Acela launch. Having even a passing interest in trains has unfortunately become more and more niche over the years, but it is entirely possible that the amount of non-railfan people who would know or care about something like this has not changed too dramatically from 2000 to 2018.
 
The same argument can be used to discontinue all LD passenger service, or at least lower their speeds to those of the freight trains they must intermingle with. That kind of thought process is not really conducive to the development of a viable thriving passenger service that competes effectively with automobiles. Brightline realizes that and is not ashamed at all to talk about 100-125 mph service and the associated costs in places where such is unheard if previously.
 
jis said:
The same argument can be used to discontinue all LD passenger service, or at least lower their speeds to those of the freight trains they must intermingle with. That kind of thought process is not really conducive to the development of a viable thriving passenger service that competes effectively with automobiles. Brightline realizes that and is not ashamed at all to talk about 100-125 mph service and the associated costs in places where such is unheard if previously.
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I don't think anyone is arguing that all things being equal, it's bad to have increased speeds and reducing travel times, however, one can make the argument that the hundreds of millions of dollars spent cutting travel times by a couple minutes could possibly better be spent elsewhere. I won't speak to whether that is or isn't what they should do, but I just think that an argument could be made for it.
 
But no one wants to figure out actually how many million of the grant was used for purely increasing speed, once they have decided it is hundreds of millions in case of the NJ segment. As an abstract statement that is fine. Operationally it is useless and possibly destructive in an unfriendly hostile environment.
 
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It is a longshot to put it mildly, but it would be great if the Boring Company could reduce the price of tunneling by 50% or more. Obviously, that is a wishful thinking number with no basis in fact at this point, but if the cost of tunneling did drop by a large amount, I wonder it the curvier, slower parts of the NEC could be straightened by going under the obstructions that would be so expensive to buy in an effort to straighten the current right of way. Getting the money for even a few miles of tunnels would be problematic, of course.

jis said:
That won’t be an incremental change. That would be building a new railroad on a new right of way [emoji57] costing mucho dinero
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Wasn't this supposed to be a test bed for Amtrak to gain real world experience in operating high speed rail service? The few minutes cut here or there is kind of irrelevant. It would be a valuable learning experience if Amtrak ran at such speeds somewhere on the NEC, no?
 
Despite the PR about the speed increase, in my opinion this project was intended primarily to reinforce the electric power supply in the North Jersey segment of the NEC. The work included added capacity at the Metuchen frequency converter, a new substation at Hamilton and various other improvements designed to solve chronic catenary voltage issues along that section of the NEC. The catenary work was an adjunct to that.

The problem with increasing train speed is the need for shorter catenary span lengths. The span length issue is not due to structure strength but the need to limit catenary movement created by the pantographs at speed. The longer the span, the greater the catenary movement (by a square factor). The existing PRR spans are in the 225-250 foot range. Those spans, originally designed for 80 mph operation, are right at the limit for 135 mph (if not longer than ideal). Spans in the 150-175 foot range are needed for higher speeds. In order to get shorter spans where there are now longer spans, new structures are needed and a lot of them. A 23-mile section of railroad would need about 700 new catenary structures. At about $200,000 each, that is $140 million just for structures. Given the logistical complexity of installing new structures on the NEC with very limited work windows due to traffic and power constraints, that estimate could be low.

I have no inside knowledge, but my guess is that the desire for higher speed lost out to the fiscal reality of the expenditure needed to achieve higher speeds. There will be a segment with constant tension and shorter spans, but some of the original catenary replacement work is now limited to hardware replacement on the existing structures while retaining the fixed termination design.

The completion of the power supply enhancements will fulfill the primary goal of the project.
 
Also the complete rebuilding of Midway Interlocking with high speed crossovers, the construction of new crossover interlockings Delcon and Adams and increasing track speed to 125mph on tracks 1 and 4 between County and Ham together with replacement of the signaling system including changes in block lengths, all this together increases speed of all non-Acela trains and increases throughput capacity irrespective of what finally comes of the catenary work.

One thing that I have wondered about is that they did not have to change spans just to convert to constant tension, which in and of itself brings advantages. MNRR did not in general change span lengths in converting to constant tension.

I think what happened is that they slapped together a proposal quickly, without much detailed planning of what was necessary for which segment to meet a proposal deadline thrown at them by FRA when Scott returned the money. After that they slowly figured out that east of Midway they could not get speed limits upto where CT is necessary and punted on the thing there. Then they badly botched the project west of Midway and finally managed to install shorter span CT for about half the planned distance, and completely punted on CT everywhere else. Also, for some unknown reason, or reason I don;t understand, they opted for a three wire system even for the shorter span segments, where the rst of the world manages fine with two wire systems. Apparently cost containment was not one of the over-riding goals of the original plan.

Anyway, now that is much water under the bridge, until the next screwup I suppose. Cynic? Moi?
 
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PRR 60 said:
The problem with increasing train speed is the need for shorter catenary span lengths. The span length issue is not due to structure strength but the need to limit catenary movement created by the pantographs at speed. The longer the span, the greater the catenary movement (by a square factor). The existing PRR spans are in the 225-250 foot range. Those spans, originally designed for 80 mph operation, are right at the limit for 135 mph (if not longer than ideal). Spans in the 150-175 foot range are needed for higher speeds.
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jis said:
One thing that I have wondered about is that they did not have to change spans just to convert to constant tension, which in and of itself brings advantages. MNRR did not in general change span lengths in converting to constant tension.
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I wonder (and I am neither an engineer, nor did I stay at a Holiday Inn last night) how catenary tension figures into the equation.

I would assume (recalling back to High School physics) that with higher tension, you would get less catenary movement (holding span length and speed constant). If that assumption is correct, then it would stand to reason that with constant tension catenary, you would avoid the low tension wires when it was hot outside (and many thanks to Jishnu for explaining that to me not long after I showed up here over 10 years ago), the overall speeds could be improved.

Empirically, this seems to be born out in the examples in Jishnu's post.
 
Granted the shorter span lengths call for a lot more spans. However there are reports that the original spans are having major corrision problems at the point where the span pole enters the earth. Since poles are going to be needed to be replaced placing 3 span poles where 2 are at present appears to be very prudent.. As for three wire CAT why remove one wire when it probably costs very little to connect to hangers. On other hand removing one wire may be costly ? That would require redesigning hanger system ?
 
I was just at Princeton Junction yesterday (actually took a ride from New Brunswick down and back to capture the 'ol Turboliners!

) and it looks like they're doing work on track 3 with constant tension in place on the other tracks already. It's unfortunate to hear of the cost overruns and scale backs, but I can't believe they're doing all this work for nothing. The non-constant tension segments from roughly Jersey Ave down to Monmouth Junction and from south of Princeton Junction to Trenton have noticeable new hangars that I guess improve the rigidity of the variable tension wires. So, I hope that means that those will be acceleration/deceleration zones that at least allow Avelia Liberty to demonstrate its 160 mph performance for those 8 miles or so of constant tension on the Princeton Junction - Monmouth Junction stretch.
 
Speaking of 160mph, does anyone happen to know the answer to my original question? Lol
 
From a reliable source on a similar thread over on Railroad.net:

It should be done by the end of this year/start of next year but there probably wont be a speed change, and they only completed the constant tension upgrade for about 8 miles vs the 13 or so they were supposed to do. All because catenary poles were not going up fast enough.
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Is this confirmed?
 

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