Swiss firm claims longest passenger train record with 1.2-mile-long locomotive | Hacker News Reader

Swiss firm claims longest passenger train record with 1.2-mile-long locomotive

news.sky.com

28 points_4489 comments

This is awesome! Just saw that in Swiss News too. Here you can find some nice pictures of the event: https://images.swiss-image.ch/event/de/1/3866/group/instruct...

I’ve always wondered - does the first coupling in a train bear the energy to pull all of the rest of the cars? And each coupling behind has one car less energy on it? Or does it all somehow even out due to some effect named after some 19th century European scientist? :-)

In which case, wouldn’t the strain on the first coupling be insane in this train?

I'm not sure about your terminology, and I'm probably not about to do much better, but yes the first coupling must bear the load of the full train, how could it be otherwise? In fact it's worse that that, the first cross section of atoms in the first coupling must bear the full load, but some atoms are pretty good at that sort of thing.

> how could it be otherwise?

In a push-pull configuration, couplings in the back of the train would experience compressive force

https://en.m.wikipedia.org/wiki/Push%E2%80%93pull_train

Touché. Although I don't think that's quite what the questioner was getting at.

>yes the first coupling must bear the load of the full train

This is only the case with a standard locomotive arrangement.

The trains involved here appear to be EMUs (electric multiple units), which have motors in most of the bogies (wheel assembles). Therefore, the lead car isn't pulling the whole thing.

Even when trains aren't EMUs, often you have a "push-pull" arrangement, such as the French TGV which has a power car at each end.

> In which case, wouldn’t the strain on the first coupling be insane in this train?

In this instance, this was not the case. There was power distributed along the train as it was composed of many powered units coupled together.

You sprinkle engines along the train

https://gorail.org/infrastructure/nuts-bolts-why-is-there-an...

I read somewhere they used 7 locomotives across the whole 2km train!

Reply on news.ycombinator.com