What is a Graphic Timetable?

A Graphic Timetable is a visual chart used by rail planners where time and distance are axes. Train movements are plotted as diagonal lines, allowing planners to instantly see speeds, stops, and potential conflicts.

What is Clock-face scheduling?

Clock-face scheduling (or Taktfahrplan) is a system where trains depart at fixed intervals (e.g., at 10, 30, and 50 minutes past every hour), making the schedule easy for passengers to memorize.

What is the difference between a Public Timetable and a Working Timetable?

The Public Timetable shows arrival and departure times for passengers. The Working Timetable (WTT) includes all train movements (including freight and empty stock), passing times at non-stop points, and technical operational data.

The Pulse of the Network: Mastering Railway Timetabling

Master the invisible art of rail operations. Learn how Timetabling utilizes space-time graphs, headways, and slot allocation to prevent conflicts and maximize network capacity.

December 11, 2025 7:40 am

What is Railway Timetabling?

Timetabling is the complex process of defining the movement of trains in terms of space and time. Unlike a simple bus schedule, a railway timetable acts as a mathematical guarantee that two trains will not attempt to occupy the same section of track at the same time. It is the core product of the Infrastructure Manager, allocating specific “Train Paths” (or slots) to various operators.

The Graphic Timetable (Bildfahrplan)

Planners do not just work with lists of numbers; they visualize operations using a Graphic Timetable. On this chart:

X-Axis: Represents Time.
Y-Axis: Represents Distance (Stations and Kilometers).
The Lines: Each diagonal line represents a train. The slope of the line indicates the train’s speed (steeper = faster). A horizontal line represents a stop (Dwell Time).

Key Components of a Schedule

Creating a robust timetable requires balancing conflicting variables to ensure safety and efficiency:

Headway: The minimum time interval required between two trains following each other. This is dictated by the signaling system and braking distance.
Dwell Time: The time a train spends stopped at a station for passengers to board or alight.
Recovery Time: Extra time buffers added to the schedule to allow a train to catch up if it encounters minor delays, ensuring reliability.

Comparison: Periodic vs. Aperiodic Timetabling

Timetables generally fall into two strategic categories, serving different market needs.

Feature	Periodic (Clock-face / Takt)	Aperiodic (Demand-based)
Concept	Trains run at regular intervals (e.g., every 30 mins).	Trains run only when needed or requested.
Primary User	Passenger Services (Metros, Commuter, HSR).	Freight Trains, Seasonal Tourist Trains.
Memorability	High (Easy for passengers to remember).	Low (Passengers must check the schedule).
Flexibility	Low (Rigid structure).	High (Optimized for specific loads).

The “Working Timetable” (WTT)

What passengers see is the Public Timetable. However, railway staff use the Working Timetable (WTT). The WTT includes operational details invisible to the public, such as passing times at non-stop stations, freight train schedules, technical stops for crew changes, and specific track allocations. It is the “master script” for the entire network.