Spain derailed with Gareth Dennis

So, LZB.

We'll come back to human error.

We'll come back to talking about investigation processes.

But LZB, let's talk about this system, this German signalling system.

Development started in the 60s.

It's an in-cab signalling system.

It was developed around the fact that Germany needed greater capacity, greater speeds on its existing railway lines.

But in doing so, it was coming to a situation where line-side signals, so that lights on sticks, traffic lights, a bit like we have when we're driving in our cars, those traffic lights become difficult to read over speeds of around 200 kilometers an hour.

It's a problem across Europe.

In Britain, we were having similar challenges as we were developing faster trains, high-tech trains.

Germany came up with LZB.

And it means it basically literally translates to linear train control.

Now, how the system works is there are control centers set up at around about 30 to 40 kilometers spacings.

And those control centers take information from the track that is picked up where the train is, what the position of the train is, speeds of the train.

And within that control center is programmed in information like gradients, curvature, junctions, and the expected performance of the trains operating that allows that system to pretty accurately create a safe operating kind of block, if you like, that the train can operate within.

And that block is sort of ostensibly a moving block.

It's not technically a...

Basically, it creates a small enough gap within that railway that the train can run that you can actually run lots of trains in quick succession, get a really nice high-capacity railway, and one that is absolutely safe.

And this system was developed in the 60s.

It was refined from the 70s into the 80s and was really deployed through the 80s and through the 90s pretty widely across Germany, Austria, and for the Spanish high-speed rail system and some of Spain's suburban lines as well.

This system is excellent.

It is an excellent, a very well-developed, very good system.

It's had its problems as any signaling system has.

Those have been addressed through its lifespan.

But the issue with any signaling system, particularly those developed actually in the era of early, or let's say the nascent period of commercial electronics, is that obsolescence becomes a problem very quickly.

So, LZB.

We'll come back to human error.

We'll come back to talking about investigation processes.

But LZB, let's talk about this system, this German signalling system.

Development started in the 60s.

It's an in-cab signalling system.

It was developed around the fact that Germany needed greater capacity, greater speeds on its existing railway lines.

But in doing so, it was coming to a situation where line-side signals, so that lights on sticks, traffic lights, a bit like we have when we're driving in our cars, those traffic lights become difficult to read over speeds of around 200 kilometers an hour.

It's a problem across Europe.

In Britain, we were having similar challenges as we were developing faster trains, high-tech trains.

Germany came up with LZB.

And it means it basically literally translates to linear train control.

Now, how the system works is there are control centers set up at around about 30 to 40 kilometers spacings.

And those control centers take information from the track that is picked up where the train is, what the position of the train is, speeds of the train.

And within that control center is programmed in information like gradients, curvature, junctions, and the expected performance of the trains operating that allows that system to pretty accurately create a safe operating kind of block, if you like, that the train can operate within.

And that block is sort of ostensibly a moving block.

It's not technically a...

Basically, it creates a small enough gap within that railway that the train can run that you can actually run lots of trains in quick succession, get a really nice high-capacity railway, and one that is absolutely safe.

And this system was developed in the 60s.

It was refined from the 70s into the 80s and was really deployed through the 80s and through the 90s pretty widely across Germany, Austria, and for the Spanish high-speed rail system and some of Spain's suburban lines as well.

This system is excellent.

It is an excellent, a very well-developed, very good system.

It's had its problems as any signaling system has.

Those have been addressed through its lifespan.

But the issue with any signaling system, particularly those developed actually in the era of early, or let's say the nascent period of commercial electronics, is that obsolescence becomes a problem very quickly.