- If you want to learn to drive a train,
there are simulators. A screen, a set of controls,
it's pretty realistic. But that's not the only safety-critical
job on the railway that needs training. The signalers who decide where trains go
are just as important, making sure that every train
goes down the right track and dealing with
disruption when it happens so that passengers can still
get where they're going. You could simulate that
in a computer, sure, but there is a more physical approach. Here in Darmstadt, Germany, there is the world's most
useful model railway. - In this place, we started in 2006 at
the Technical University in Darmstadt. We had a similar facility since 1936. We have about 500 square metres
of space available for the trainings, and a track laid out. It's a fictional layout, 1.2 kilometres.
We have some fictional names. Some of the stations
are named after persons that helped developing this facility. We are training actual signalmen here.
They are taking exams here. - So these are the oldest systems
on the Deutsche Bahn network? - Okay, yeah, it's right.
It's mechanical interlocking. Everything is worked manually. The blue levers are for the points,
the red levers are for signals. - And that's our train?
- Yeah, that's our train. - And it's going that way.
- This way, right track. - Not into that tiny train. - That's right.
- Okay. - So I have to know which
points have to be turned. It's point number one and two.
So if you want to try it. - So, yep.
- You have to take it and turn it around. - All the way down.
- Just to lower position, yep. - And, oh! - It's turning over there. - Okay. - So we have also point
number 7, 8, 9, and 10. - Okay, so every time I do this... - One point will turn. Just a simulation.
- Yes. But it's an accurate one.
- But it works like a real signal box. - 'Cause in the real world,
I would be pulling that and that will be pulling
through pulleys and levers and actually physically
switching the point. - Yeah.
- All right. - So here we just have a computer
who is turning the model points. - Right, so you lock that into place, it detects that I've done that,
and the computer goes "pht". - Yeah, that's it.
- Okay. So we've set the points, the
next is safety interlock. And that's a German thing? - This is a German thing.
Well, it's just common in German. We have what we call a route locking. So we want to open a special signal,
so we have to take the right route lever, which is called P2. - Because it says 1, 2, 7, 8, 9, 10, which is what I've just moved.
- Yep, that's it. - So do I pull up, down?
- Down, down please. - So this lever checks if all
the points are set correct, and second thing, he
will lock all the points. So we can't move them back. - What happens if I were
to pull the wrong lever? - Just try it.
- Right, okay. - Try it, it won't work. - Oh!
- It's closed. - It's a physical lock.
- Yep. - I kind of assumed that
was just going to beep at me or complain, but that's an actual physical interlock.
- This is real, physical. - Right, so now I can't even-
- Yeah, try it. It's not possible to pull them back.
- You can't even close the lever. - Yep.
- Wow, okay. So that's- - So this is an old computer. It checks if everything is
set at the right position. - Wow, okay. So we have put the points in position, interlocked everything
to make sure it's safe. - That's right. - And then we just- - Last step is put the
signal to an off position. It's P2.
- Which is going to be... - The P2.
- P2, all right. - Just like point levers
to an off position. [machine beeping] And now the train driver
sees a green signal, and he can move on. - But it takes a few seconds
and the computer kind of simulates... - It's a simulation, because
he has to release his brakes before he can start. - So what's the last thing we need to do? - So now we have to lock the line
so another train can't follow. So we have to tell us
and the next signal box there's a train on the line. So we have to put down the button
and to produce some electricity. - Oh!
- Just put it down. - Pull it down.
- And 10 times, please. [box whirring] - So that would have sent
a bell ringing or something in another signal box saying
we've got a train coming. - Yep, that's it. - So that's the manual
ones. What came next? - Interlocking, which is
called electromechanical. That's the next thing, which
was about 50 years later. - All right, let's do that. - We've got the next station,
which is an all-electric interlocking from the 1950s. Our train is coming, we see the red arrow. It's a train intersection marker. Train will stop at the
entry signal of the station. - Because that's a red and green light,
and there's a red light there. And this is the station. These
are all the tracks, okay. - So we can see all the tracks. You can see in the
direction of the points. And now we want this train to enter
into track number two. So, now if you want to operate a point,
we have to do a two button operation, which means you have to
push the button of the... - Yep. - And second one is this blue one. Now it starts to blink.
The point is turning. And now it's on the left. - And now it's on the left. So the train is now going the right way. So if there's nothing
else in this section, you can then turn that to green? - Yep. So, we have to make an
entry-exit operation. We are starting at the entry signal and we want to move into track number two. There are two buttons. - Right.
- Try it. - So I have to push that one? - Yep, and same time track number two. - These two.
- Yep, and nothing happens. - Okay! - Because we are missing
two another points. We have a flank protection,
which is missing. There might be a train waiting here and he might just start
to roll into our train. - And he'll, right. So I need to change that one as well. So now there's no way that a
train coming the other way- - That's right.
- Can come in, okay. - And second point, we have to
operate as point number one, which is called the overlap. So if a train won't stop
at an exit signal... - Yep, it'll derail there
at the moment, won't it? - Yes, and maybe he
could hit another train, so we have to reserve this
space also for the train. - Okay. So that one?
- Yep. Which is called the overlap. - All right.
- So, now try it again. Entry exit operation.
- Entry exit. Lights up? Green light.
- Lights up green light. Train will enter in the next,
I don't know, one, two minutes. - And somewhere out
there on the big model, a train has started moving. That's lovely. And this is all electrical circuits. This isn't microcontrollers,
this is all physical wiring. - Or relay interlocking. - There is really something
in having that view of what you're doing versus a screen and a vague idea in a diagram. Like, I can see the train
pulling into the station. That's lovely.
So that's the 1950s, and there's still some of
this equipment out there. - Of course.
- Of course. What's the most modern version? - That's the computer interlocking.
And now I will show you. - Lead the way. - All of the interlockings
that you used today are still in use in the
German rail network. The numbers, for example, of
the mechanical interlockings are dwindling at the moment. In the future, all of
them will be replaced by electronic or computer interlockings. The physical railway that you crash will always stay in your mind, even if it's a model train! And you have the ability
to get an overview about the situation during
any sort of disruptions, not only the really focused
view that you would have during this disruption. - So this is the future?
- Yep, that's the future. - So which train are we moving? - We are try moving a
train which is called 201. - 201, okay. Yeah, I see it. - So all you have to do is an
entry exit operation, with a mouse. - Oh, so just the single
button push from earlier? Everything else is automatic? - Everything else is going automatically. So first thing is you have
to move the mouse pointer to the red triangle on
the right side, please. It's the exit signal for the station. And now move on to just one mouse click. And now next train, please, on the right. - The blue-
- The blue one to the right. That's the exit. - And click that?
- Click there. - I don't know why I'm being so nervous. It's a model train set. But
in my head, this is serious. So it's just done all the button
pushes that I did earlier. All the lever pulls.
- Yep. - Two mouse clicks. - At the moment, nothing has operated. It's just, "I want to go," from
track number five onto the line. - And it's doing all the interlocking? - Yeah.
- Making sure that nothing's in the way.
- And now have to tell the computer, "Okay, I want to do it." There's a button which is called in German
"Verarbeiten" which means OK. And after you push it,
all the points are moving. - All at the same time.
- Yep. And the signal is going to... - And the signal's gone to green. - Yep. That's it. - It absolutely makes sense,
but also it seems so much easier. I know it's not. You've got exactly
the same checks here. - Of course.
- That were being done by the systems, that were
being done by the circuits and then being done by
the physical interlocks. But here it's code and we
can see the train progress. Like, the lights go red when
there's a train in the section. That's so clever. - Big difference is I do have to operate
2, 3, 4, 5 stations. [Tom laughs] So it's not as simple as it looks like. - Right. - You know the computer game? - You have to do the same amount of work,
just over a much bigger area. - That's it.
- All right. Thank you so much.
- Thank you.
This is Extremely German, I hadn't ever wondered How they trained DB operators but then you see it in action and it's like, Yep, that's clearly the most efficient way to use a model railway
I found myself super impressed with how safety-focused the 60+ year old mechanical system was.
In other countries, you just relied on the operator simply not making mistakes. Whereas in Germany they figured out every allowed configuration and the operator had to configure the switches then lock in to confirm those configurations. All completely mechanically driven.
I love systemic problem-solving like this.
Tom Scott has to make the best videos on YouTube. Straight into the video with content. No ads in the middle of the episode. No begging for likes or subscriptions. Just pure content from the first second to the last second of video
I like trains.
I genuinely appreciate that Tom Scott makes these videos. Every time I've learned something new after watching one of his videos.
That's not the Swayze Express...
ah! yes . The Germans are big fans of their trains. They're very efficient. Well organized.
You forgot to consider the Swayze express.
As a dumb American how common is English in Germany? Or does he just know it because companies send people from different parts of the world to this training place?