For RFP (on page 10) that resulted in the section of the ALC42s (on page 14) they RFP'd "Options for catenary power or DC 3rd Rail power draw "
Was that an optional option, in which (future dual mode variants of the selected) ALC42 can do the 3rd rail but not catenary?
No...because the dual-mode RFP is separate and has existed on a separate trajectory for years now. What it means is that since the dual-mode RFI was issued 5+ years ago Siemens has refined its would-be design to the point where it's asking to bake in the carbody mods into the base diesel platform now so the same frame can be ripped out for the dual version. Siemens is all about the modularity of its platform, and parts/design commonality between the Sprinters and Chargers is a humongous attraction for Amtrak...so being able to uniframe their whole U.S. diesel universe has to be considered holy grail for their manufacturing scale. At the time of the duals RFI reply they were *near* the specced weight target but not *at* the weight target on projected dual design, and said that they could produce a 110 MPH (i.e. same as Genesis) dual within-weight but needed more R&D time to make weight with a 125 MPH spec target.
With a half decade's time for that extra R&D and a very small weight shortfall to begin with, it's overwhelmingly likely that they've got their design now fully sorted. Since the carbody changes sympatico with those dual-mode design changes and making weight therein came
after the SC-44, they are being specifically included up-front in the ALC-42 specs (both AMTK and VIA versions). I imagine after some cutoff point the commuter rail SC-44's that are being ordered at steady clip will be migrated over to the same one-size-fits-all frame as a "Version 1.1" rollup of sorts that bakes in all other improvements. The dual-mode version would presumably have highly modularized E-mode and diesel mode compartments because that's how they do it with the Eurozone Vectron dual-modes. And the modularity would mean that the E-mode compartment can be swapped between DC third rail and AC pantograph variants without design changes. That's where the New York triple-procurement of NYSDOT/Amtrak + Metro North + LIRR duals (anywhere from 70 to 95 units depending on whether the MTA goes all-dual/no-diesel outside of ConnDOT or continues with split dual GCT/Penn fleets and straight-diesel shuttle fleets) offers a way in for VADOT/NCDOT, PennDOT, and ConnDOT/MassDOT to later buy a minority fleet of pantograph duals at really nice price point. However, dual power plants are still a big enough production to require very different configuration from a straight-diesel setup. So basically they're just resetting some global carbody changes that fit all variants, and then minimizing the design deviations for the mode compartments to just the interior engine room.
It
is very likely possible to bake a stock ALC-42 and add a third-rail helper engine just for getting in/out of Penn/GCT and nothing more. That's not new at all; 1950's NYNH&H EMD FL9's (currently the newest addition to the Cape Dinner Train's historic fleet) did it with third-rail helpers for nearly 5 decades. The jet-turbine powered Turboliners were quick-retrofitted for third-rail helpers. Even Bombardier's JetTrain, the laudable but futile effort to port the Acela I design to diesel territory with a newer-fangled 125 MPH jet turbine design, had a third-rail helper on its lone prototype. That's not hard at all, and it appears they are rolling up the flex to augment exactly that way on the base ALC-42 build. But New York is
very specifically ordering "equal modes" for the triple-procurement, and is doing so because the LIRR + MNRR units with many more miles of third-rail territory to tap so strongly outnumber the Empire/Penn units, and they get their optimal ordering scale buying all 3 at the same time with the same make. So even if a helper-shoed ALC-42 is a better value in an Amtrak-only universe...this isn't an Amtrak-only universe. New York State is going to be the sole owner of all 70-95 units split between the three agencies, so "equal mode" duals are where they get their paydirt. Reserving the capability for helper E-mode in the ALC-42 may have jack nothing to do with Amtrak or U.S. market prospects at all; it may just be a design tweak that starts here at first available opportunity but gets backported to the Euroland "Vectron" series and nets them a few actual sales over there instead.
What we are now hearing is that Siemens has got its "equal mode" design fully sorted for that RFP, and is advance-baking any global changes to the Charger frame into the ALC-42's by request so it's ready to roll for that duals RFP. Also probably means that Bombardier, which is now actively delivering its second batch of ALP-45DP "equal mode" pantograph duals to NJ Transit, was never able to make any headway against the weight target in the RFI...which it was in much tougher straits than Siemens against because the ALP-45 starts out way heavier than the Charger with fewer feasible avenues for improvement. The second batch for NJT are merely refreshed clones at same insane obeseness, not any sort of "Version 2.0's" that made any significant strides towards target. BBD seems to have waved the white flag on feasibility of meeting the New York RFI specs, while it only took Siemens a "Version 1.1" tweak--nothing nearly as radical as a "Version 2.0" overhaul--to make weight. So that pretty much telegraphs how the bidding is going to play out.