Acela & Amtrak NEC (HSR BOS-NYP-WAS and branches only)

First time seeing a new train set live, this afternoon at south station. They look great but yeah the engine vs passenger car misalignment is noticeable.

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I would assume Alstom and Amtrak have done extensive testing of the aerodynamics of the Acela II, given that it's designed for a max speed of 220mph w/o tilting. Certainly doesn't look great, though.
 
SCNF in France ordered a bi-level variation of the Aveila Liberty too, known as Aveila Horizon, for TGV. It uses the same power cars as the American version, just with a more pronounced roof hump to meet up with the slightly taller carriages. That one has a smooth transition between the power car and the carriages, however. So the discrepancy is definitely unique to the American Aveila Liberty design.

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Do the TGV ones have tilting passenger cars? Did Amtrak spec something that compelled them to crib Airo passenger cars?
 
Do the TGV ones have tilting passenger cars? Did Amtrak spec something that compelled them to crib Airo passenger cars?
I don't think the TGV cars tilt, though the Aveila Horizon design is modular enough that tilt options are available for purchase. The Amtrak carriages are based on the older single-level Alstom AGV family, married to the power cars from the TGV Aveilas. So it's a little bit of a mongrel (albeit standardized) design. All the AGV photos I've found, though, don't have that hexagonal bulge-out and do interface smoothly with their power cars, so the hex design might've been an Amtrak customization (possibly related to the ADA and netting adequate aisle width for wheelchairs).
 
As I understand it, the maximum speed for trains that tilt is 186 MPH. I don't know exactly why. That's 300 kilometers per hour so maybe anything designed for speeds higher than that is meant for dedicated high speed corridors which are built with fewer curves to begin with.
 
I would assume Alstom and Amtrak have done extensive testing of the aerodynamics of the Acela II, given that it's designed for a max speed of 220mph w/o tilting. Certainly doesn't look great, though.
Laws of physics tell us that there has to be a drag penalty on power requirements -- and the drag penalty is a fourth power effect, so a little drag cause a lot of excess energy use.
 
That misalignment is the immediate tell that we are not serious about high-speed rail

I'm actually curious about just how much that misalignment will impact things. Once we eliminate all areas with curves where coaches will be tilting and/or speed restricted, bridges with speed restrictions, station areas, pretty much all of Metro North territory, etc, how much tangent track exists where passengers cars wouldn't be tilting and the train can achieve speeds where the drag would be impactful?
 
I'm actually curious about just how much that misalignment will impact things. Once we eliminate all areas with curves where coaches will be tilting and/or speed restricted, bridges with speed restrictions, station areas, pretty much all of Metro North territory, etc, how much tangent track exists where passengers cars wouldn't be tilting and the train can achieve speeds where the drag would be impactful?
Let's be real, there are CONVENTIONAL (non-HSR) intercity rail routes in Europe & Japan that have higher average speeds (90+mph) than the Acela (which ranges from 60-85mph depending on route). Acela isn't really about speed, it's about getting priority over other trains, greater seating comfort, and having fewer stops. There is like 60+ minutes of padding end to end in the schedule that can be cut out before we need to worry about raising the top speed.
 
Does anyone know how many trainsets will be assigned to NYC-BOS after the new Airos are all in service?
 

Official notice letter here. The FRA awarded two separate grants through its Federal-State Partnership last year for NY Penn Station. The Penn Station Capacity Expansion (Penn-X) one was going to be an Amtrak project; the Penn Station Reconstruction (Penn-R) one was going to be MTA-led. Now both projects are being combined under Amtrak’s umbrella, so the FRA has pulled its $72 million Penn-R grant to the MTA, and apparently is also pulling funding from Amtrak’s grant awards to make them focus more on planning/design.
 
New infrastructure, including a combination of high-powered macro towers and compact small cell nodes, has been installed at more than 30 sites between New Haven and the New York border.

Supported by a $6 million investment from AT&T, the project is significantly boosting the company’s telecommunications network and delivering faster, more reliable LTE and 5G service.

An additional five sites are expected to launch along the New Haven Line—the busiest rail corridor in the country—later this year.
 
The Transit Costs Project has released their proposal for overhauling the NEC; among other things it calls for having all of the commuter agencies upgrade to EMUs. I'm sure that'll be a piece of cake. https://pedestrianobservations.com/2025/05/05/the-northeast-corridor-report-is-out/
It's not the existence of EMU's; that's duh-obvious for every member agency and should be a piece of cake if a couple laggard agencies would get on with reforming themselves. It's the "one EMU make to rule all of NY/NJ" that's a real eye-roll. They want multiple thousands of units of this mythical "M10" to have quadruple-electrification (750V DC third rail, 25 Hz 12.5 kV AC overhead, 60 Hz 12.5 kV AC overhead, 60 Hz 25 kV AC overhead), East Side Access-compatible clearances despite the fact that the electrification guts on the roof and undercarriage prevent that by a wide margin on the triple-electrification M8's, less weight and better acceleration than the incumbent triple-electrification M8's, have an M8/M9's-like optimized passenger flow even though NJ Transit didn't ban curved platforms like the MTA/ConnDOT institutionally did (quarter-point doors open a gap that vestibule doors don't), be nearly off-shelf imports from Europe despite there being no applicable floor heights compatible with the NEC, and be less overcustomized than any current NEC rolling stock despite the fact that nobody else does quad-voltage WITH such restrictive sub-Plate B clearances WITH multiple signaling systems (LIRR's cab signals are different from the NEC's) WITH 48-inch platform heights. All at once. And then cite a particularly overcustomized British loading-gauge make with incompatible floor heights as a recommended source vehicle for this supposed-to-be-nearly-off-shelf adaptation.

Like...WHUT? How do those disparate pieces all fit together such that everybody runs thru to everybody on complete-perfection fleet unity with complete-perfection frictionless within-cost procurement, much less complete-perfection ops unity amongst 4 balkanized agencies (MTA-MNRR, MTA-LIRR, ConnDOT, NJ Transit). There's an awful lot good and sensible in this outfit's recommendations, both in the final report and the early previews that've been circulating for over a year. But the trans-NYC rolling stock recommendations and run-thru assumptions are...awfully pollyannaish and glossed-over on degree of difficulty.
 
The Transit Costs Project has released their proposal for overhauling the NEC; among other things it calls for having all of the commuter agencies upgrade to EMUs. I'm sure that'll be a piece of cake. https://pedestrianobservations.com/2025/05/05/the-northeast-corridor-report-is-out/

One kind of odd thing is their recommendation to plan to run 400m long trains, which requires extending platforms at most stations that would get HSR. The entirety of their reasoning is this:
In the technical standards section, we assume Amtrak should procure 16-car, 400-meter (0.25 mi) long trains. This is based on a rudimentary model of ridership on the NEC if the speed upgrades we propose are undertaken and if fares are set at a reasonable rate, comparable to the TGV or ICE system.
The plan already calls for sending much more frequent trains, which itself doubles or quadruples capacity along the line. That's huge. Then they throw is this recommendation to expand the trains to increase capacity another 25%, which is marginal, and comes at a great cost. (Maybe I missed it, but the report doesn't seem to fully math that out. Likely in the $100s of millions.) And all on pretty weak sounding reasoning. A "rudimentary model?" Trying to guess demand at least a decade from now? Guessing at the ticket prices? Maybe they're right, or there's some better explanation, but jeez, that seems flimsy. For that money, it really seems like they need to clearly argue that quadrupling capacity isn't enough, but quintupling is.

It's disappointing because most of this report seems really reasonable, and mostly well done. They propose fixes for scheduling problems, promote a lot of best practices, promote EMUs, and pick some strategic infrastructure investments. They do seem to make reasonable proposals that would shave hours off the trip from Boston to DC. This is very much worth reading! But then there is also stuff in there that's surprisingly sloppy. There's stuff that's not thought out much, or at least poorly explained. There's a bunch of just confusing writing, typos, and poorly displayed data. Compared to TCPs other work, this seems slapdash.
 
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One kind of odd thing is their recommendation to plan to run 400m long trains, which requires extending platforms at most stations that would get HSR. The entirety of their reasoning is this:

The plan already calls for sending much more frequent trains, which itself doubles or quadruples capacity along the line. That's huge. Then they throw is this recommendation to expand the trains to increase capacity another 25%, which is marginal, and comes at a great cost. (Maybe I missed it, but the report doesn't seem to fully math that out. Likely in the $100s of millions.) And all on pretty weak sounding reasoning. A "rudimentary model?" Trying to guess demand at least a decade from now? Guessing at the ticket prices? Maybe they're right, or there's some better explanation, but jeez, that seems flimsy. For that money, it really seems like they need to clearly argue that quadrupling capacity isn't enough, but quintupling is.

It's disappointing because most of this report seems really reasonable, and mostly well done. They propose fixes for scheduling problems, promote a lot of best practices, promote EMUs, and pick some strategic infrastructure investments. They do seem to make reasonable proposals that would shave hours off the trip from Boston to DC. This is very much worth reading! But then there is also stuff in there that's surprisingly sloppy. There's stuff that's not thought out much, or at least poorly explained. There's a bunch of just confusing writing, typos, and poorly displayed data. Compared to TCPs other work, this seems slapdash.
Alon Levy wrote about the 16-car trains a few months ago, and went into deep detail on the required station renos: https://pedestrianobservations.com/2025/02/19/16-car-trains-on-the-northeast-corridor/

You're absolutely correct: the math doesn't add up for a legacy-system retrofit. They're talking about things like radical re-segmentation of platform assignments from local commuter rail agencies to segregate the longest platforms to HSR conflicts-be-damned; outright skipping hard-to-modify stops like Stamford, Trenton, and Back Bay; a major do-over of New Haven because of a conjoined proposal to do a major curve bypass east of the station; ugly hacks like not opening up all doors on the trains at some stops despite that being problematic with reserved seating; and on and on. The station mod cost blowouts are literally going to be in the billions. And that's without even touching the fact that 16-car trains put a tremendous individual strain on the power supply, which likely needs to be upgraded in multiple spots if they're to be run frequently. The thoroughly-mongrel NEC absolutely isn't comparable at all to post-WWII greenfield HSR systems that overrepresent the long-consist HSR ranks, and there's been no effort whatsoever to right-size the associated costs.

I mean, we run 12-car Regionals every day of the week (absorbing some boarding inconvenience at a few too-short stations), which is 33% more capacity than the 8-car Acela 2's. We could get halfway to target with minimal cost and disruption. But no...somebody in the world did it under completely different circumstances, therefore we've failed by not shooting for absolute perfection damn the logistics.
 
One thing I'd personally like to have seen is what it would take to convert the entire NEC to 60hz 25kv to eliminate or at least minimize the need for all of that 3 frequency switchgear. A bunch of it is approaching it's centenary soon to begin with.

For the moment ignoring the MTA 750V 3rd rail which will have to stay and SEPTAs ex-Reading infrastructure, as far as I'm aware, Metro North & SLE M8s, NJT Arrows, ALPs & MLVs, SEPTA Silverliner Vs & ACS64s, and MARC's HHP8s are all certified to run on all three modes anyways, even if SEPTA doesn't do it in practice. The only fleet on the corridor that can't is SEPTAs Silverliner IVs, which was supposed to be replaced with CRRC EMUs that would have been full corridor compatible, and whatever replaces the CRRC contract likewise will also be.
 
It's not the existence of EMU's; that's duh-obvious for every member agency and should be a piece of cake if a couple laggard agencies would get on with reforming themselves. It's the "one EMU make to rule all of NY/NJ" that's a real eye-roll. They want multiple thousands of units of this mythical "M10" to have quadruple-electrification (750V DC third rail, 25 Hz 12.5 kV AC overhead, 60 Hz 12.5 kV AC overhead, 60 Hz 25 kV AC overhead), East Side Access-compatible clearances despite the fact that the electrification guts on the roof and undercarriage prevent that by a wide margin on the triple-electrification M8's, less weight and better acceleration than the incumbent triple-electrification M8's, have an M8/M9's-like optimized passenger flow even though NJ Transit didn't ban curved platforms like the MTA/ConnDOT institutionally did (quarter-point doors open a gap that vestibule doors don't), be nearly off-shelf imports from Europe despite there being no applicable floor heights compatible with the NEC, and be less overcustomized than any current NEC rolling stock despite the fact that nobody else does quad-voltage WITH such restrictive sub-Plate B clearances WITH multiple signaling systems (LIRR's cab signals are different from the NEC's) WITH 48-inch platform heights. All at once. And then cite a particularly overcustomized British loading-gauge make with incompatible floor heights as a recommended source vehicle for this supposed-to-be-nearly-off-shelf adaptation.

Like...WHUT? How do those disparate pieces all fit together such that everybody runs thru to everybody on complete-perfection fleet unity with complete-perfection frictionless within-cost procurement, much less complete-perfection ops unity amongst 4 balkanized agencies (MTA-MNRR, MTA-LIRR, ConnDOT, NJ Transit). There's an awful lot good and sensible in this outfit's recommendations, both in the final report and the early previews that've been circulating for over a year. But the trans-NYC rolling stock recommendations and run-thru assumptions are...awfully pollyannaish and glossed-over on degree of difficulty.
I feel like the complexity here is exactly why these agencies need to get together and standardize. We should at least be able to agree on things like signalization and electrification scheme and a dynamic envelope. It doesn’t necessarily have to be “one EMU to rule them”. There can be a finite number of variants (e.g. a tight-clearance 3rd rail capable set of requirements vs a mainline express set of requirements).
But getting to a point where companies can put together off-the shelf NEC-spec designs (for rolling stock, stations, tunnels, etc.) and pitch them to multiple agencies would be huge. Getting to the point where agencies along the NEC could borrow or sell rolling stock to one another would be huge. Getting to the point where capital costs are easier to estimate, alternatives are easier to compare, and systems are easier for mathematicians to optimize would be huge. You’d see fewer studies, faster timelines, more vendor competition, and more confident investors. All good things.
 
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One thing I'd personally like to have seen is what it would take to convert the entire NEC to 60hz 25kv to eliminate or at least minimize the need for all of that 3 frequency switchgear. A bunch of it is approaching it's centenary soon to begin with.
Probably a lot, because 25 kV requires twice the electrical clearance of the current 12.5 kV from overhead structures. Metro North inventoried years ago lots of overhead bridges on the New Haven Line that would conflict with a voltage change, and the North and East River tunnels feeding Penn are likely to have some problems too unless the tunnel trackbed can be reengineered for a little more clearance (floor-anchored sleepers in lieu of ballasted trackbed, etc.). The ex-Pennsy southern NEC had its electrification more overengineered from Day 1 so is likely to have much fewer...but not none...clearance issues. A more realistic move might be to just convert the frequency of the Washington-Sunnyside/NYC from 25 Hz to 60 Hz while keeping the same 12.5 kV voltage. It would require lots of substation mods, but not much in the way of OCS mods at all except for changing out the circuit breakers (Metro North changed over from 25 Hz to 60 Hz at same voltage in 1984 in a literal weekend shutdown). The voltage taps in the vehicles that switch between 12.5 kV and 25 kV sources are not particularly bulky, but the 25 Hz transformer cores are really heavy and space-intensive as well as being pricey custom-design because Amtrak+SEPTA are the only 25 Hz railways left in the world. Having a consistent 60 Hz source would at least make the existing M8's kosher for running into New Jersey, uncapping lots more thru-running possibility without requiring a superduper new unicorn vehicle.

Nobody seems to be studying this, though.
For the moment ignoring the MTA 750V 3rd rail which will have to stay and SEPTAs ex-Reading infrastructure, as far as I'm aware, Metro North & SLE M8s, NJT ALPs & MLVs, SEPTA Silverliner Vs & ACS64s, and MARC's HHP8s are all certified to run on all three modes anyways, even if SEPTA doesn't do it in practice. The only fleet on the corridor that can't is SEPTAs Silverliner IVs, which was supposed to be replaced with CRRC EMUs that would have been full corridor compatible, and whatever replaces the CRRC contract likewise will also be.
The to-be-retired NJ Transit Arrows also can't switch on-the-fly from 25 Hz to 60 Hz, even though they have both transformer cores and both 12.5 kV and 25 kV voltage taps to manual-switch between; they're captive to end-to-end same-voltage runs with any power switches needing to be done offline. The Silverliner IV's have no definitive replacements identified, even though SEPTA holds some so-far unfunded option orders on the NJ Transit MLV EMU's. SEPTA's canceled CRRC order was for push-pull coaches (but, being stupid SEPTA, they shouldn't be running push-pull ops at all in this day and age on a 100% electrified system).
 

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