That's crazy! :) But it's a genius idea, surely saves lots of energy. - Éric Senterre

Assuming the train goes 200km/h and is 100m long, that would mean over to 1.5g's for acceleration / deceleration. "Please hold on" :D - John Mueller

Seems foolish. The main train cannot get full with such little top shuttles. How do they maximize the number of travellers? - Eric Sausse

had a similiar idea during endless stops on local trains too, always failed to come up with an idea for a sufficient fail-safe solution for this time-critical process. - Max Friedrich Hartmann

@Eric: If they provide access to passengers to go "downstairs" then the problem is solved. Now my concern was: what if I want to ride through several stations? That would mean I have to switch shuttles at each station (seeing that shuttles get switched at each station). But again, that problem can be solved if I'm sitting "downstairs". - Rami Botros

@Rami: do you think shuttle can have the necessary capacity for main train stations? If so then the concept is interesting. Thanks for your response. - Eric Sausse

My impression is that you could easily move between the main cabin and the 'transition cabin' while it's docked. My biggest concern would be what happens when more people want to get off the train than will fit in one transition cabin? - Kevin Fox

Would definitely work better in a typical commuter scenario where people are mostly getting on and heading for the same destination. - Reto Meier from fftogo

Whoa. But let's see passenger planes that don't land, and then color me impressed. - Kirk Kittell

Kevin, doesn't every normal train have the same theoretical problem that more people want to board it than fit in? You could solve this with reservations, more frequent trains, etc. no? And in case of emergencies or other rare situations I'm sure the train could stop for a change... - Philipp Lenssen

@John: I read your comment and thought of Spaceballs: "Sir, and you better buckle up!" "Ah, buckle this. Ludicrous speed, go!" - Kirk Kittell

I imagine you could extend the length of the boarding capsule to the length of the train itself if necessary. But what happens when there's more people in the capsle than can fit on the train... - Reto Meier from fftogo

But does it really save energy? I mean I always have to decelerate a capsule and accelerate another one per station. Only way it saved energy here is that the capsue is way smaller than the train. But I could save just as much energy if I just shrank the size of my train to that of the capsule.. Any thoughts about that? [But it does save a lot of time..] - Rami Botros

The conductors would be really pissed if you held the doors on that train. - Benjy Stewart

Jason, the little cabin car will be stuck either to the station or to the train, so you won't be stranded... - Philipp Lenssen

I always thought they should just drop the last car off the train shortly before they got to the station and let it coast to a halt. - j1m

a nice idea, with two reservations: (1) limited "bandwidth" and (2) aerodiynamic imperfection. - 9000

Damn cool. It requires ascending and descending from the boarding car to the train car, which might be difficult for handicapped and elderly. - Robert Konigsberg