Acela 21 (Avelia Liberty) development, testing and deployment

Amtrak Unlimited Discussion Forum

Help Support Amtrak Unlimited Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
The only thing I would add is that the power in Watts drawn for each voltage should be the same, although the efficiency of the transformer at 25Hz vs. 60Hz may be different this affecting power draw slightly. However the lower voltage means almost twice the amps drawn through the pantograph which might be an issue along with the variable tension catenary not providing as uniform a contact surface. I am not an EE so take my comments with a large grain of salt.
That is a very hefty assumption. Usually power drawn is regulated based on the design voltage of the territory in order to keep things from overheating in lower voltage territories due to the consequent higher current draw. That is why total available power for lower voltage catenary is less and operational characteristics are degraded to some extent. The question is to what extent such regulation is in effect for 12.5kV vs. 25kV. I don't know the answer to that.

Another thing that is visible in the catenary in 12.5kV segment is the additional Messenger Wire in the catenary which is needed to deliver the higher current efficiently, sometimes with a heavier contact wire which requires more support. They are usually absent in 25kV electrification except in extremely heavy duty freight lines.
 
Last edited:
Speculation: Once Amtrak has 4 fully approved AX-2s it might launch a soft inauguration of service this fall. Have 2 in NYP and 2 in WASH. The AX-1 trips they would replace can remain standby along with the -2s that might be down for some reason. It might require some reservation tweaks to prevent overbookings. However, this speculation ignores what about BOS. I have not heard that an AX=2 has visited BOS for training but vaguely think it has visited.
 
Last edited:
Speculation: Once Amtrak has 4 fully approved AX-2s it might launch a soft inauguration of service this fall. Have 2 in NYP and 2 in WASH. The AX-1 trips they would replace can remain standby along with the -2s that might be down for some reason. It might require some reservation tweaks to prevent overbookings. However, this speculation ignores what about BOS. I have not heard that an AX=2 has visited BOS for training but vaguely think it has visited.
They have visited Boston last year and recently, so it’s possible.
 
Speculation: Once Amtrak has 4 fully approved AX-2s it might launch a soft inauguration of service this fall. Have 2 in NYP and 2 in WASH.

The chances of this are astronomically low. The new trainsets aren't approved for speeds over 90mph except when testing, also of note Amtrak is planning to do cant deficiency testing this fall.

Sorry to be the buzz kill.
 
The chances of this are astronomically low. The new trainsets aren't approved for speeds over 90mph except when testing, also of note Amtrak is planning to do cant deficiency testing this fall.

Sorry to be the buzz kill.
I was about to mention this, but you beat me to it.

The cant deficiency work will actually determine what the new speed limits will be for these sets on many of the curves.
 
Note: I did say fully approved. If the testing is behind schedule ( which almost always happens) of course it will be later. So Once they are fully approved maybe Amtrak will have a soft inaguration.
 
Expecting revenue service anytime before FY2023 Q4 is basically living in Fantasyland, to those who are ‘speculating’
I have been trying to say that whenever these speculations come up. But some people are just incorrigible optimists.
 
I was about to mention this, but you beat me to it.

The cant deficiency work will actually determine what the new speed limits will be for these sets on many of the curves.
Lets hope they are lenient for these speed limits that are determined in these tests. The regulations on cant def (to my understanding) are far too strict currently and could be loosened without having any impact on safety
 
I was about to mention this, but you beat me to it.

The cant deficiency work will actually determine what the new speed limits will be for these sets on many of the curves.
Any idea how much this new tilting system could improve the travel times between Boston and NY given the extreme curves in that segment? Or is most of the NY to Boston section of the NEC a lost cause for getting that travel time down to 3 hours flat?
 
Any idea how much this new tilting system could improve the travel times between Boston and NY given the extreme curves in that segment? Or is most of the NY to Boston section of the NEC a lost cause for getting that travel time down to 3 hours flat?
To significantly shorten travel times between Boston and New York, what they really need to do is get all four tracks on the Metro North between New Haven and New Rochelle back in operation and figure out how they can dispatch things so that the Amtrak trains can do a consistent 70 mph rather than always poking along at 30 mph behind much slower commuter trains that make a lot of stops. That will have a lot more benefit than worrying about getting another small speed increase for relatively short stretches of track.
 
To significantly shorten travel times between Boston and New York, what they really need to do is get all four tracks on the Metro North between New Haven and New Rochelle back in operation and figure out how they can dispatch things so that the Amtrak trains can do a consistent 70 mph rather than always poking along at 30 mph behind much slower commuter trains that make a lot of stops. That will have a lot more benefit than worrying about getting another small speed increase for relatively short stretches of track.
Is this a symptom of Amtrak not owning those tracks and being deprioritized vs Metro North/MTA contrasted to how Amtrak is given priority over NJT south of NYC? Sounds like those commuter trains need to be sent to sidings the moment Amtrak begins to approach them.
 
Lets hope they are lenient for these speed limits that are determined in these tests. The regulations on cant def (to my understanding) are far too strict currently and could be loosened without having any impact on safety
Based on any actual professional training, or just a gut feeling?
Any idea how much this new tilting system could improve the travel times between Boston and NY given the extreme curves in that segment? Or is most of the NY to Boston section of the NEC a lost cause for getting that travel time down to 3 hours flat?
Even if you solve that, I think that the track centers are too close together to enable tilting for any actual high speed operation.
 
There will not be 4 unimpedied tracks New Rochelle <> New haven until at least year 2050. All the moveable bridges being replaced are going to restrict MNRR tracks to 3 and for short times of 2 - 3 months will be just 2 tracks across the moveable bridge location. That is for the new north lift bridge. Walk bridge is now just 3 tracks and will be just 2 sometime late 2023 or 2024. Then starts over when building the south lift bridge..
 
Back
Top