Siemens to manufacture 83 Airo Intercity Trainsets for Amtrak: Design, Delivery, Acceptance

west point wrote: ↑Sat Aug 31, 2024 4:02 am At first glance it would seem that the Airos with 4 powered trucks would equal the same as the NEC regionals that are now having 2 ACS on those 8 car regionals. However, since the APV will weight less than the ALCE's its factor of adhesion will be somewhat less so not as much HP can be applied during slower speed increases. To complicate acceleration rates further the original as I understand it will be only 7 cars? So less train weight.

I think you are right, but the APV will also house the very heavy transformer. Even in ACS-64 the transformer is a major part of its weight, which will compensate for the adhesion. Also the electric cabinet is placed in the APV. I can't find it, but i thought that also a part of the APV will house the cafe car and "kitchen" also adding weight.

There may quickly be some of those train sets with fewer or more cars that will also complicate the results.

It has not been clarified to my satisfaction if the APV will be used when in diesel mode for acceleration from standing starts to the speed that the ALC can apply full power to its traction motors. Also, in diesel mode there is the HEP draw that can be variable taking power away from the traction motors. Or in worse cases shutting off HEP when needed on steep grades that now happens occasionally.

When the train is in diesel mode, only 2 trucks of the leading locomotive are powered. If the locomotive is also powering the trucks on the APV the diesel engine is not powerfull enought to supply at least 4400 KW of electric power needed for those 8 or 6 trucks and HEP. The trains doesn't have to reach 125 mph, so logical they aren't powering the APV in dieselmode.

west point wrote: ↑Sat Aug 31, 2024 4:02 am At first glance it would seem that the Airos with 4 powered trucks would equal the same as the NEC regionals that are now having 2 ACS on those 8 car regionals. However, since the APV will weigh less than the ALCEs its factor of adhesion will be somewhat less so not as much HP can be applied during slower speed increases. To complicate acceleration rates further the original as I understand it will be only 7 cars? So less train weight.

There may quickly be some of those train sets with fewer or more cars that will also complicate the results.

It has not been clarified to my satisfaction if the APV will be used when in diesel mode for acceleration from standing starts to the speed that the ALC can apply full power to its traction motors. Also, in diesel mode there is the HEP draw that can be variable taking power away from the traction motors. Or in worse cases shutting off HEP when needed on steep grades that now happens occasionally.

Do not get me wrong the concept of the APV is very important IMO especially when there is the occasional traction motor failure on an ALC Airo Train set!

If you are running a multiple unit set of 2 or 3 P42s only ONE of the locomotives is suppling HEP to the train. That is 8800- 13200 total hp less the 500 or so for the HEP. Plenty enough to climb anything without shutting down HEP. Before you say but I'm talking about... ran the B&A with 5 car train sets with one P42 or P40, never had to shut the HEP down while climbing the ruling grade. During the Gunn era the LSL would normally be a single P42 and 10 to 12 cars ALB-CHI. The Mohawk is not completely flat there is a pretty good grade in Batavia NY train made it every night without the loss of HEP.

SRich wrote: ↑Fri Aug 30, 2024 11:07 am

TheOneKEA wrote: ↑Tue Aug 27, 2024 10:21 pm We got the specs of the APV yet?

What kind of specs are you looking for?

The specs that you quoted below, and that you also highlighted as still being ambiguous and not at all clear.

SRich wrote: ↑Fri Aug 30, 2024 11:07 am The airo trainset will be have the same hp as a single ALC 42 in diesel mode with 2 electric motors for a truck.
The APV has at least one powered truck, but Amtrak FY24-29 Five Year Service and Asset Line Plans (page 92 configuration B1) states that

"The passenger car closest to the locomotive will be an Auxiliary Power ehicle (APV) containing a pantograph, transformer cabinet, and supplemental powered trucks for use in electrified territory. Power drawn from the APV will also be fed to the traction motors in the locomotive to ensure sufficient acceleration when operating on the Northeast Corridor. "

From a grammatical point of view it can be read that both trucks of the APV are powered. Each electric motor has a 729 KW rating. 8 times of that will be around the 5800 KW (out of my head) But if there are only six. Then there is around 4400 KW available. HEP will be atleast 1 MW or 1000 KW, which will not limit the traction power in electric territory.

This is the part that I still want to get some clarity on: how many powered trucks does the APV have (one or two?), how many traction motors will be available in total (six or eight?), and will either or both of the APVs' powered trucks be functional when the ALC-42E is operating in diesel mode? In another thread on this forum there was a lively debate about whether or not the ALC-42E's prime mover and generator can deliver enough power to operate all of the traction motors when trying to accelerate to track speed, and this debate was based in part on how many powered trucks the APV has and if the weight penalty of dragging the transformer around outside of the electrified parts of the NEC with too little output from the prime mover would blunt the benefits of a hybrid trainset.

This all seems to be a dumb way to make excuses for extending electrification, or just swapping power.

And create a surplus of fairly new ACS-64s that go where? The MBTA refuses to do anything electric, MARC probably won’t want them, and SEPTA has no beed for anymore.

40% of corridor services extend into Virginia where there's no wire. The cost of stringing that wire would be a lot more than the cost of a few locomotives, and given all the power issues Amtrak experienced this summer, having backup power is not the worst idea. I suspect that the percentage of services continuing south will be increased once you have a fleet with dual mode capability. The swapping of power causes delays on a regular basis, so it's not really "just" swapping power that this move eliminates.

Per https://www.amtrak.com/content/dam/proj ... Y24-29.pdf, it sounds like there's a plan to use at least some of the ACS locomotives for Palmetto service through FY2034. Keystone trains will continue to use a mix through FY2034 as well. Even on the corridor, a complete phase-out is not planned until FY2029. Knowing the speed at which these things move, I suspect it will get pushed out even longer. That said, this does seem wasteful. Time will tell what will happen.

Nasadowsk wrote: ↑Sat Aug 31, 2024 10:23 pm This all seems to be a dumb way to make excuses for extending electrification, or just swapping power.

And create a surplus of fairly new ACS-64s that go where? The MBTA refuses to do anything electric, MARC probably won’t want them, and SEPTA has no beed for anymore.

MARC will want a few, due to the deal they made with the Fredrick Douglass Tunnel and that they have HHP-8's as their only electric engines. It's designated as Electric Engine Only (although diesel will probably be used for emergencies).

MBTA... really should electrify. They're just getting around to upgrading to PTC/ATC and laying down fiber optics.

The ACS-64s will not work in Chicago as the Metro Electric and South Shore lines are 1500v DC.

scratchyX1 wrote: ↑Sun Sep 01, 2024 1:01 pm I'm assuming Marc worked out a more equitable electric rate with amtrak as Part of the exchange.
It will speed up penn line trains.
It also occurred to me that if the battery Apv work, marc/vre could order some for run through service, as there is no way 1st street tunnel can get wired up.

Definitely 5 minutes time savings between BAL and WAS, but it's very start/stop service in comparison to Amtrak with a lot more stations. For run-through... um... they found a lot more off the Brunswick line wanting run-through. There's a thread in the DC area forums about that.

scratchyX1 wrote: ↑Sun Sep 01, 2024 7:35 pm Yeah, we've discussed Brunswick run-through, I was wondering about feasibility of penn line run-through.
But, there's also a limit to 1st street tunnel slots.

Feasable with a combo APU/SC-44? Yes. Worth it? Not quite so much. I'd be interested myself given recent events and if the cards hold in the future.

A whole bunch of updates here including a bunch of Cascades Airo Sets (and locomotives) in progress:

Does anyone know the actual weight of a 25 /60 hZ transformer for both the ACSs and the ALCs if different? Now I was on a CAL Z where different engineers had to turn off the HEP going up to the tunnel from Denver and up Soldier Summit.

west point wrote: ↑Fri Oct 11, 2024 8:28 pm Does anyone know the actual weight of a 25 /60 hZ transformer for both the ACSs and the ALCs if different? Now I was on a CAL Z where different engineers had to turn off the HEP going up to the tunnel from Denver and up Soldier Summit.

I don't know your answer specifically as far as weight. But the difference between 25Hz and 60Hz motors is the number of poles (or the way the coils are wired) in the motor. Likewise in transformers. They could have the same weight.

The number of windings difference between the primary coil and the secondary coil of a transformer determines how much the voltage is stepped down. With 12kV or 25kV going to the primary winding in a transformer, the difference is by a factor of two to get the same voltage on the secondary. Either one winding has twice more windings, or half the windings of the other. The one with more windings, whichever way it is done, should weigh more than the other. But since the difference is usually accomplished by center tapping the same winding in the transformer, and the entire winding is still physically there, the weight should be the same. Only electrically are you using half the center tapped coil.

That's just basic electromagnetics at work, I admit I don't know the specifics with these locomotives.