Tuesday, June 30, 2015

Tight Railway Schedule on the Keio Line

EMU Keio 8000 series (left) approaches the preceding 9000 (right) series near Meidaimae Station
 
Keio is one of the busiest railway lines in Japan. Its congestion during rush hour is well known among Tokyoites. Currently, this company operates 30 trains of 20m long 10-car trains in the peak one hour toward the city center on the double track section.

It's too soon to be surprised. You will see "a train jam" during rush hour, if you visit a major station such as Meidaimae. While one train is standing at the station for passengers getting on and off, the next train is already approaching and waiting just behind the standing preceding train. The distance between the two trains is only tens of meters. Too close!

What has made it possible for this tight railway schedule? It is because of the new ATC (automatic train control) signal system. Keio Electric Railway introduced the latest signal system in 2011. Each train has begun to calculate its appropriate speed to maintain a distance from its preceding train by an on board computer, receiving a signal from surface equipment. Of course, train brakes work automatically, if there is a risk of colliding with the preceding train.

As a result of the new system introduction, all railway traffic lights had been removed from the track. The "traffic lights" had been moved from the track to speed meters in the cabins. That's why all trains can stop at any point on the track, even just behind a preceding train.

Tight railway schedule on the Keio Line... it is a new Tokyo institution.

 
EMU Keio 7000 series (left) approaches the preceding 9000 (right) series near Meidaimae Station