No U Don't Have Train.

The following is a conversation between Jack and someone from the train company.

Why wouldn't they work outside? It's not like they're magically gonna come off the rails once they leave the dome.
All of your trains are outfitted with fail-safe emergency brakes. On power loss, you have about 15 seconds before they are applied and the train comes to an abrupt, unscheduled halt. You can't even tow these things without power.
I thought you said the tracks were in decent shape? Why would the contacts? sliders? come off the power rail for that long?
A) I didn't, I said they are in surprisingly decent shape after being exposed to the elements for a century without any maintenance. B) That power rail isn't gonna be of any use because it doesn't deliver any power.
What do you mean? Why not?
Where does the rail get its power from?
The power grid.
Not quite, but close enough. What do we not have outside?
Of course there is a power grid outside. It's what powered the old world just as ours powers the city.
There used to be one, that much is correct, but it hasn't been used or maintained in a century. Even if you did somehow manage to get part of it working, I still wouldn't trust it. And where would you wanna get the electricity to run it from?
From a substation. We fix up one of those and use it to power the grid.
Great, now you have a local grid attached to the high voltage grid. And what do you wanna power that with?
What? The substations make the power. It's where all the power in the city comes from: Two substations – one in the wall next to this airlock and the other one is by the other airlock.
There is a third one deep below Central Square. These are indeed where the electricity in the city comes from but they don't make it. They get it from a power plant outside, a bit northeast of here.
The dome powered by the outside world? People be believing strange things these days...
I don't have to believe. I was there when the city was built and, more recently, I helped replace a failing generator at said power plant. You might have noticed the outage.
Uhuh, sure buddy. Since you've been doing nothing but spewing nonsense all this time, I'm just gonna have one of our guys drive a train up there and we'll see what happens.
I'll get some popcorn. Watching this is gonna be fun...

The rails start ringing and a train of the Sunside Cove Metro approaches. It slows down and comes to a halt before the power rail's gap for the switches in front of the closed airlock. Inside are a driver and the railway official. Jack reaches into his backpack, grabs a bag of chips – he didn't find any popcorn for the occasion – and opens it. The headlights turn off and the driver leaves the driver's cabin. A moment later, the first door opens and he climbs out.
No, I am only going to drive the first segment in there. We don't need the entire train stuck in the tunnel if it doesn't go to plan.
It's gonna be fine. What could go wrong?
Jack replies loudly so both of them hear him: A lot.
You shut up.
The driver says: I'm inclined to agree with him.
He turns around and walks to the end of the first railcar where he proceeds to detach the hoses and cables and unhooks the couplings. Then, he returns to the front and climbs back inside.

The headlights come back on and a compressor kicks into action. A few contactors click inside the train. After a moment, the door closes. The train sits like this for a few minutes until the compressor turns off again. Jack shoves a handfull of chips into his mouth. The inner door of the airlock begins to open, creaking and buzzing as it slowly moves up.

The motors begin to hum and the first car of the train starts moving towards the airlock. It loses power as it rolls over the switches and the headlights dim. Jack puts his bag of chips aside and presses the button on his watch that lights up the display. He begins to count in his head:
One, two, three, four, five...
The railcar rolls completely into the airlock. It's still decently far away from the other door.
Six, seven, eight, nine...
It rolls deeper into the airlock, beyond Jack's view.
Ten, eleven...
Loud hissing sounds from inside the airlock – the train's failsafe mechanism begins to release the pressurized air from its tanks.
Twelve, thirteen, fourteen...
A loud clunk followed by screeching and grinding noises as the emergency brakes are applied.
Fifteen.
Jack grabs his bag of chips and gets up. He walks onto the tracks and looks into the airlock, stuffing his face as he watches the dim Rücklichter? rear lights? go out.

A few minutes pass and nothing happens. Eventually, Jack hears one of the doors getting unlocked with a key and sees it getting pushed open by hand. He gets off the track and sits back down next to the rails, continuing to stuff his face with chips. A bit later, he watches the driver and the railway official doing the walk of shame, the latter seeming pretty close to an aneurysm.
Told you so.
The railway official loses it completely, stampfen? and jumping around while screaming some apparently very colorful language – Jack doesn't understand a single word.

The train driver proceeds to walk to the rest of the train but Jack stops him. "It's too far back. There are only two feasible ways to get it back out: Getting power on the track inside the airlock or dismantling the brakes so it can be towed."