An operating system for extra long urban trains

The paper presents a new method for operating urban railways that, without building any additional infrastructure or significantly changing the passengers’ level-of-service, allows an agency to run trains up to three times longer than existing station platforms and still fill them with passengers. An operating system (OS) underpinning the new method is presented. The only requirement of the rolling stock is that the doors in different parts of each train (e.g., its cars) can be operated independently. The extra-long trains (XLTs) can protrude beyond both ends of the station platforms—in different ways at different stations. The proposed OS has a train-side and a passenger-side. On the train side, it includes train organization and station-stopping protocols and on the passenger side a new information system that organizes passengers at the platforms as required by the train-side protocols. These protocols specify the composition of each train and what it does at each station; i.e., whether it stops or not; how it aligns its doors along the platform; whether each door opens or not; and the set of destinations advertised by each open door. A general menu of train-side protocols is presented, as well as a crude mathematical framework for their optimization and analysis. Numerous examples illustrating key concepts are also presented.