Acela 21 (Avelia Liberty) development, testing and deployment (2018 - 1Q 2024)

[PVD]

need 100% high platforms as well, I recall

 

[jis]

Trainset 2 has reached 165 mph on the NEC as of 1:39 am, 12/24/20.

That's an amazing amount of arcing at the pantograph catenary interface in a constant tension catenary section. Hope this is a temporary thing that they are working on fixing.

I talked to someone I know at Amtrak about the arcing. He said they are acutely aware of it. It is a problem with the aerodynamics of the pantograph that they are in the process of evaluating some design modifications to fix.. I just know a few relevant techies and operating staff in Amtrak. I don't know anymore on the marketing side anymore.

 

[west point]

Is that arcing in the constant tension portion that Amtrak was using a cheaper method ?

 

[jis]

Is that arcing in the constant tension portion that Amtrak was using a cheaper method ?

No it is everywhere. It is a defect in the pantograph. Specifically this video is in the full proper constant tension segment.

 

[west point]

Interesting. That brings forth several questions.
1. Is this the same pan used on Acela-1s , or Sprinters?
2. Is this pan different than those use in Europe or the far east?
3. Is the distance from the top of the Acela-2 to the wire taller than in Europe or the far east ?
4. Does the arcing happen when the train rocks ?
5. Is the zig zag of the Amtrak constant tension at a different ratio than Europe or the far east ? We know there is little to no zig zag on the old variable PRR CAT.

 

[Acela150]

Interesting. That brings forth several questions.
1. Is this the same pan used on Acela-1s , or Sprinters?
2. Is this pan different than those use in Europe or the far east?
3. Is the distance from the top of the Acela-2 to the wire taller than in Europe or the far east ?
4. Does the arcing happen when the train rocks ?
5. Is the zig zag of the Amtrak constant tension at a different ratio than Europe or the far east ? We know there is little to no zig zag on the old variable PRR CAT.

1. No.
2. Yes.
3. I don't think so.
4. No. I can't speak to how it occurs, but it's not due to "rocking".
5. I don't think it is. But I could be wrong.

 

[jis]

Not due to rocking. It is due to problematic aerodynamics of the panto.

 

[west point]

Is this pan problem an example of either / or Amtrak and Alstom saying proven pans in Europe and Japan not invented here ? Could it be a licensing problem that Amtrak or Alstom did not want to pay the fees to use these designs ? Why in the world was the pan not tested in a wind tunnel ? Arnold wind tunnel I have been told does have vacant times ?

 

[jis]

Is this pan problem an example of either / or Amtrak and Alstom saying proven pans in Europe and Japan not invented here ? Could it be a licensing problem that Amtrak or Alstom did not want to pay the fees to use these designs ? Why in the world was the pan not tested in a wind tunnel ? Arnold wind tunnel I have been told does have vacant times ?

Your assignment is now to go find answer to these questions before you ask anymore of them Questions are really easy to conjure up. Now do the hard work

 

[me_little_me]

Your assignment is now to go find answer to these questions before you ask anymore of them Questions are really easy to conjure up. Now do the hard work

Isn't that what west-point is doing? Researching the answers by seeing if someone with expertise knows the answer. Much better to ask someone if a correct answer is available than to do all the research only to find out with a lot more work that an associate already knew the answer.
Possibly if Amtrak executives asked the right questions instead of hiring tons of consultants to redo the research, they could make better decisions.

 

[west point]

If I research a point myself the answers are limited to just my research. Persons who know much more can tell all of us what each problem's solution is. That way total knowledge is spread over more persons. We do not need to hoard our knowledge especially to help expand passenger rail.

 

[jis]

Well, looks like the leg pulling didn't go too well. People took it too seriously.

So more seriously. Things in US are indeed quite different from Europe, so stuff from Europe do not just port over without change, notwithstanding the fond hopes of people who do not have deeper knowledge of the subject matter. For example...

1. Anything from Europe plopped down on American rails rides like ****. That is because the flange profile used in the US is very different from the European one. Ride quality is intimately related to the wheel tire and flange fitting exactly with the rail head, the shape of which is different in the US from Europe. Indeed, even within the US, it is different between the freight railroads and the NEC high speed trackage. Has to do with quality of high speed ride requiring a different shape form what is good for heavy freight.

2. The US electrification on the NEC is 12.5kV which requires much heavier catenary and contact wires to carry the larger current necessary for transmitting the same amount of power to the train. So the pantograph-catenary dynamics is very different from what it is for light weight 25kV catenary. Most likely the problem on the NEC has to do with getting this fine tuning taken care of by trial and error in the 12.5kV segment. Whenever a small parameter is changed one has to go through re-calibrating everything to work right with it.

For some reason even the 25kV electrification in the US appears to use much fatter cables than is typical elsewhere. I have no idea why. Possibly because feeder posts and booster transformers are spaced further apart allowing line voltage to drop lower than is customary elsewhere - but just a guess. Either way, that would also have an impact on the dynamics at the panto-catenary interface.

Heck, even UK with its new fangled catenary mounting system in Scotland and London and West, had to fiddle around with things to get them to work right!

A gentleman who is involved inthe Acela 21 trials mentioned that they believe that the thing that needs tuning is the aerodynamic fins on the panto to get the dynamic forces right to reduce the arcing. It is a hypothesis that they were working on at that time. Since then they might have discovered something else or even fixed the problem. I have not heard anything further from them.

So in general, I am somewhat loath to insinuate incompetence or NIH as the cause of every piece of teething trouble.

 

[west point]

JIS: Unless changed lately the only Amtrak 12.5 Kv 60 Hz CAT is the replacement of the Hell Gate line from Shell to Gate. PRR / NYNH&H CAT - Gate - Sunnyside - NYP - WASH at last time has only been raised from 11.0 to 11.5 to 12.0 Kv 25 Hz.

 

[jis]

JIS: Unless changed lately the only Amtrak 12.5 Kv 60 Hz CAT is the replacement of the Hell Gate line from Shell to Gate. PRR / NYNH&H CAT - Gate - Sunnyside - NYP - WASH at last time has only been raised from 11.0 to 11.5 to 12.0 Kv 25 Hz.

Yeah whatever the voltage is which is somewhere around half of 25kV. .5kV this way that way is not really material in so far as cable size goes.

 

[jis]

 

[Steve4031]

Interesting video in that you see the train operating at increasing speeds each time it passes.

 

[jis]

This is the first time that we will get a side by side comparison of the ride quality on conventional trucks vs. Jacob's trucks based articulated trains on the apparently inevitably inferior US tracks.

 

[railiner]

This is the first time that we will get a side by side comparison of the ride quality on conventional trucks vs. Jacob's trucks based articulated trains on the apparently inevitably inferior US tracks.

Why do you think that is so? I mean, why doesn't Amtrak build its own tracks equal, or even better, than the foreign railways? Cost?

 

[jis]

Why do you think that is so? I mean, why doesn't Amtrak build its own tracks equal, or even better, than the foreign railways? Cost?

Heavy freight that runs on substantial part of the NEC makes the cost of keeping it as glass smooth as typical European passenger tracks quite prohibitive apparently.

 

[railiner]

Heavy freight that runs on substantial part of the NEC makes the cost of keeping it as glass smooth as typical European passenger tracks quite prohibitive apparently.

I thought CSX has their own mostly parallel route...at least between DC and NJ...they should also share that route with NS, if it would get NS off NEC....

 

[jis]

I thought CSX has their own mostly parallel route...at least between DC and NJ...they should also share that route with NS, if it would get NS off NEC....

Conrail Shared Assets has trackage rights to get to many sifdings for delivery and pickup. In addition to that Perryville to Bayview carries some heavy Coal trains, and there is some freight traffic around Washington DC too. None of those have an alternate route available and are part of the original deal.

 

[me_little_me]

Conrail Shared Assets has trackage rights to get to many sifdings for delivery and pickup. In addition to that Perryville to Bayview carries some heavy Coal trains, and there is some freight traffic around Washington DC too. None of those have an alternate route available and are part of the original deal.

So can Amtrak upgrade two tracks for higher speed and prohibit freight on just those? Then when the freight RRs complain, they can tell them they have to pay a zillion dollars more or sue. That's what NS and CSX do now when Amtrak complains about poor track slowing down faster passenger trains and being shunted aside in violation of the agreements or wanting to go back to using the Sunset in Florida.

 

[Acela150]

So can Amtrak upgrade two tracks for higher speed and prohibit freight on just those?

No. That's not practical.

 

[jis]

Besides straight line tracks are not the problem. It is keeping the interlockings in good order that is hard when you cannot restrict axle loads. Besides the commuter railroads now have diesel engines that have axle loads that would put a Coal hopper to shame.

 

[daybeers]

Besides straight line tracks are not the problem. It is keeping the interlockings in good order that is hard when you cannot restrict axle loads. Besides the commuter railroads now have diesel engines that have axle loads that would put a Coal hopper to shame.

I feel this is the bigger issue. Maybe things will improve as engines become more efficient & lighter in the years to come.