My husband and I are going up the wall trying to remember where we saw a particular image. We’re remembering trains that break themselves into parts, recombine, and continue on.
What we can’t remember is where we saw this mutually recalled image. About all that we recall for certain is that it was either a movie or TV show, set at some point in the future, and that we saw it within the last year.
One possible candidate is “Minority Report”, TV series version.
Probably not what you are after but Back to the Future III has a self-mutating steam engine at the end, when Doc comes back to say hi to Marty and introduce his two kids.
I’ve seen concept animations on TV or on the net where they had trains picking up and dropping off cars on the fly. Passenger cars would be on a station siding and as a train came by they would accelerate to match speed to hook on to the end of the train. They also had a method of dropping cars off the end or middle of the train as well.
The idea as I remember it was to save time as the whole train didn’t have to stop and wait at the station for folks to load and unload. Perhaps some energy savings as well because the entire train didn’t need to stop and start.
There was an episode of Banacek where a valuable prototype of a revolutionary new car is loaded on a flatbead railroad car in the middle of a short train, between two boxcars. When the train arrives at its destination, the whole rail car is missing. Everyone on board swears the train didn’t stop.
Banacek eventually discovers that a strong steel cable was strung from one boxcar to the other, the train was separated, the flatbed diverted onto a siding, and the cable winched in to couple the two boxcars together. He demonstrates how it happened with a model train set at the end of the episode.
I remember seeing an animation of a conceptual train design where a high speed train could have passengers joining and leaving, without the main part of the train ever stopping at stations between start and end; it involved a detachable upper floor - passengers wishing to disembark would go upstairs on the train; the upper compartment would be closed off, then as the train approached the station, the upper compartment would engage with a separate set of elevated rails, which would lift it clear of the train and decelerate it into the platform; the same process in reverse would be used for passengers wanting to join - a set of elevated rails would accelerate the partial carriage and unite it with the train as it passed through.
That’s clever, although I suspect in real life it would be rather difficult. Somewhat reminds me of the scene in Breaking Bad where they arrange to stop a train in the desert and pump out the valuable liquid chemical and then refill the car with the exact same weight of water so the theft is not detected until far too late to do anything about it.