Can trainsets such as the Acela Express and other bullet trains be doubleheaded? If so how is that done?
yes; you just put them together - most likely you’ll need to get a larger power pack, such as a MRC Tech 4 350.
Are we talking about a locomotive at both ends of the train (as in the prototype) or adding a second locomotive to one end?
I believe the Bachmann HO scale set has one powered and one non-powered locomotive (the N-scale set uses dummy locomotives with drive unit in a passenger car).
Model, or prototype?
I’ve never heard of high-speed locomotives being separated from their cars, except for maintainence, but I have seen pics of french TGV trains doubled up.
The Bachmann Acela can’t be doubleheaded because there’s no provision for a coupler in the nose.
VIA Rail does it all the time. Sometimes you will see two loco’s at the front, once in awhile one in the middle which is actually two trains that will eventually split and the odd time one at the rear.
The Acelas run right past the backdoor of the office I work at and I’ve never seen an additional locomotive attached to the end of a trainset. As stated earlier, the Acela trainsets already have two power units - one at each end
There is a coupler behind all the fairings - I remember seeing a photo of the power units being moved to the NEC after they were first built
I have seen the trains with the flying toasters doubleheaded, not sure if it was because of a breakdown or some other reason