– The Gotthard Base Tunnel is the longest and deepestrail tunnel in the world, 57 kilometers through the Alps. Literally, through.It's called a “base tunnel” because it's at the base of the mountain. At its deepest point, there are more thantwo kilometers of rock above. It's so far down into the groundthat the earth in there is hot. Without ventilation, the air temperaturewill be more than 40°. Around the turn of the century,.
There were two devastating firesin road tunnels under those mountains, and the authorities here in Switzerland want to make sure that nothing like thatcan ever happen again. How they do that is fascinating. So here's what's going to happen. We're going to see the control centerthat watches over the tunnel, and also visit one ofthe intervention centers, with the firefightersand first responders that'll step in if theworst were to happen.
And then I want to show youwhat I reckon is the most important bit of safety equipment. It isn't anywhere near the tunnel, and most people willprobably never notice it. But before that, we startat the control center, just over there. – In the Gotthard Base Tunnel, there are six freight trains and two passenger trains,per hour, per direction. This means that at the sametime, there are several trains.
Inside the tunnel, inboth of the two tubes. The Gotthard Base Tunnel isdivided into three thirds. If there is a disturbancein one of these thirds, the train can be divertedat one of the two changement points, into the other tube,to bypass the disturbed section. There are different sectionsto control the traffic. The signal box controls the track. The movement authority isgiven by the signal box, and by the traffic controller.
If there is a disturbance on oneof the systems in the tunnel, then we have differentpossibilities. First of all, we get noticed by an alarmthat there is a problem. They first of all try tofix the problem remotely. If this is not successful, they can send people onsite to try to fix it. – This tunnel is actually a bit of atourist attraction in itself. You can get driven in,down the service tunnel, on a guided tour, and end up at thisreinforced, windproof, visitor's window.
With 8cm-thick glass,and watch the trains go by at anything up to 230km/h. That was terrifying! – If a train has a technicalproblem, first of all the train driver tries toreboot the train system. If it's not successful,we have the firefighting train, which goes into the tunnelto tow out the broken train. In case of an incident inthe tunnel, let's say a fire, we have two interventioncenters, North and South.
“Intervention center” meansfirefighting stations. They get an alarm, andwithin five minutes, usually both of the firefighting trains go into the tunnelfrom north and from south at the same time to fight the fire. They have the obligation tobe on any point in the tunnel within 45 minutes. Firefighting train is a convoyof firefighting trucks on rail. They bring water in, foam liquid.They bring special equipment, tools,.
To handle any possiblesituation inside the tunnel. At the two emergency stops, there is a possibilityto refill their water. If people have to beevacuated in the tunnel, they do not walk out of the tunnelbecause it's much too far. The train brings them to oneof two evacuation stations, where the passengers can gointo the evacuation tube. This evacuation tube is under pressure,so fresh air is streaming in. They are safe becausethey have enough oxygen,.
And smoke cannot enter. Then they go to thenext evacuation section, where the evacuation trainis waiting for them. We have to be able toevacuate the entire tunnel within 90 minutes. – As I went round today,one of the team said that if there ever is anevacuation or a fire in the tunnel, several other thingshad to go wrong first. Yes, you can never protect.
Against every possible weirdcircumstance, but you can try. Which brings me here, to what's basically themiddle of nowhere in Switzerland, about 15km away from thesouth entrance to the tunnel, and to this gantry over the tracks. 15km sounds like a lot, but at thespeed Swiss trains can travel, that could be about four or five minutes. And while it doesn't look like much, this gantry scans every train, at speed,before it even gets near the tunnel.
There are sensors on thetrack around here too, and if the train has anything unbalanced, any hot spots that look out of place, anything poking out,then it's not going into the tunnel. – We have laser systems which measurethe profile of a train. Maybe the load of a train has moved, and doesn't respect any morethe necessary profile to enter a tunnel. We have heat detection,where we can detect overheated axles oroverheated brakes. All these controls, they happenat usual commercial speed.
Of the trains, in differentpoints, all over Switzerland, and we get about 200 alarms per dayfrom these measuring stations. If we do not confirm analarm within 30 seconds, the train is stopped automatically. It's not an emergency stop, it's…but it's quite… you feel it! If a train seems to be wrong, it gets to a side trackwhere it has to wait. If the inspection says,this train is okay, then it can continue its journey,.
If not, the owner of the trainhas to resolve the problem before the train can continue its journey. – Yes, there are lots of systems in placefor if “the worst happens”, but prevention is better than cure, and for me, this gantryis the most important bit of safety equipment here, because the best solutionis to stop problems before they even start.