in trains, when they have different carriages that you can walk into, why do they have doors on them? Why not just have an open train?

Question

This is for trains in the UK that are near London, I don’t know if it’s the same in other places.

In: 0

Answer 1

Some DMU/EMUs in Austria have seemless passtrough between the carriges but the old Eurofima wagons still have those doors.

The difference between modern DMU/EMUs and Eurofima wagons is the flexibillity of arranging the wagons you need to make a train.

The doors allow for much greater variety to configure fancy things like portion working, where one part of the train is decoupled fom the rest for departure to a different destination. The doors allow for those things to be more flexible.

You can also do portion working with DMU/EMUs, but you are limited to those units.

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Let’s assume that you depart from Vienna and head to Wels for dividing up the train into two parts each heading to Salzburg and Passau. With DMU/EMUs, you can only divide in the middle, witch doesn’t make sense when you know that more people want to Salzburg than to Passau.

The solution?

Using seperate wagons with said doors that you can arrange to yours hearts content.

The doors help in that regard, that they can be locked up, so no one can fall back out/no one can sneak into the part heading to Salzburg when they bought tickets to Passau.