I was out in central Pennsylvania today and, on the way home, decided to swing by Horseshoe Curve while I was out there. I was really surprised at how many shiny new double stack cars and containers there were (and a pair of ancient 60’ flats that somehow managed to survive). Anyhow, one of the trains had this:
In these parts, 99% of the trains I see are nothing but hoppers, so I’ve never seen whatever this is. Obviously its three container chassis in some kind of framework. Would I be correct in my reasoning that its a means of transporting new chassis around and that the frame is so they can be lifted from flats/spine cars? Are these frames reusable? The NS logo on it leads me to believe it is.
Also, does anyone else have pictures of something like this? I think it would make a very interesting model and would definitely like to pursue this.
Sounds to me like you nailed the answer yourself!!! Interesting photo!
Is it possible that this unit is lifted off and dropped on a set of wheels & axels? I’ve seen these stacked trailer frames being pulled down the highways but I’m afraid I’ve paid no attention as to how it was accomplished.
Wayne
Looks like stacked trailer or container frames with their wheels loaded separately. They travel much better that way. 
I think they’re stacked on flatbeds by large forklifts. I saw that once at a local company that repairs trailers, but I don’t know if that’s the standard for loading them.
Those may not be new chassis. They may well be, i believe after looking through my MR book on intermodal modeling, container spine trailers, there is a picture of a very similar looking container spine trailer, albeit with BN lettering in the book. I would assume that it may be a way of getting trailers from one port to another cheaper/quicker than hauling then across-country behind a tractor unit.
there is also a picture of a large, very odd looking forklift type truck in the book with row after row of these type of chassis stacked up behind it in an ope-air storage facility so i would assume that they may also use something similar to that to load it onto the car.
That is a roadrailer train.