I've been doing some research on the ALC-42E's (Charger variant) for use in the New York Metro area. As everyone knows, the E versions will be dual modes (love them or hate them). There will be two variants of the "E's" for Amtrak's National Network and certain state-supported corridors:
https://www.railwayage.com/passenger/in ... trak-airo/
-the Charger locomotive is coupled to a powered, pantograph-equipped passenger coach called an APV (Auxiliary Power Vehicle). The APV has an underfloor transformer to handle the Northeast Corridor’s 25kV and 12.5 kV AC catenary power, a 4QS (Four-Quad Chopper), and four powered axles with AC traction motors. The APV is connected to the Charger locomotive with a DC link. In AC catenary mode, the Charger’s diesel engine and traction alternator are shut down; the APV is powering its own four traction motors as well as the four on the Charger, for a total of eight. Siemens calls this “distributed traction.”
-Battery-hybrid push/pull trainsets equipped with a Charger locomotive and a Battery Coach with a DC Link but without powered axles. The Battery Coach supplies traction power to the Charger locomotive on routes or locations (such as some stations in non-electrified territory) where diesel emissions are prohibited or restricted, for example, on Empire Service trains originating in Penn Station New York that currently use dual-mode (diesel/third-rail) P32AC-DMs.
The benefit of using a power trailer is that you still get the full utility of a diesel engine, while being able to operate on catenary where available. I'm not sure what the range on a standard Charger is, but the benefit here is huge. You also can service the engine separately from the trailer. Simplifies maintenance it seems.
So obviously, these will be used to bridge non-powered gaps and eliminate engine changes at Hartford, as well as bring trains into Penn from NYS-supported Empire Service. They could be used for new service such as those proposed to Scranton over the Lackawanna Cutoff, and new Inland service HFD-SPG-WOR-BOS.
Now, about the two NYC area MTA commuter services: the MTA's LIRR and MNRR. There's no mention anywhere of an ALC-42E being used with a trailer car for DC. So I guess what they're going for could be called an "SC-44E".
From Wiki:
https://en.wikipedia.org/wiki/Siemens_C ... (New_York)
In December 2020, New York's Metropolitan Transportation Authority approved a Federal Transit Administration-funded $335 million contract for 27 dual-mode locomotives based on the Charger design. The new locomotives will replace the 27 existing GE Genesis locomotives used on the Metro-North Railroad's Hudson Line, Harlem Line, and Danbury Branch; they will use third rail electric power to enter Grand Central Terminal. The first 19 locomotives are scheduled to be completed in mid-2026. The contract has options for 144 additional locomotives: 32 for Metro-North, 66 for the Long Island Rail Road, 20 for the New York State Department of Transportation (for Amtrak Empire Service trains), and 25 for the Connecticut Department of Transportation.[68][69]