Time–distance diagram

A time–distance diagram is generally a diagram with one axis representing time and the other axis distance. Such charts are used in the aviation industry to plot flights, or in scientific research to present effects in respect to distance over time. Transport schedules in graphical form are also called time–distance diagrams, they represent the location of a given vehicle (train, bus) along the transport route. A time–distance diagram is generally a diagram with one axis representing time and the other axis distance. Such charts are used in the aviation industry to plot flights, or in scientific research to present effects in respect to distance over time. Transport schedules in graphical form are also called time–distance diagrams, they represent the location of a given vehicle (train, bus) along the transport route. In project management, a time–distance diagram (other names: Time-chainage diagram, Time–distance chart, Time-chainage chart, Time–location diagram, Time-location chart, March chart, Location–time chart, Orthogonal Diagram, Line of balance chart, Linear Schedule or Horse Blanket Diagram), is a method of graphically presenting a time schedule for all types of longitudinal projects such as pipeline, rail, bridge, tunnel, road, and transmission line construction. Activities in time–distance diagrams are displayed both along a time axis and along a distance axis according to their relative linear position. This allows showing not only the location of the activity but also the direction of progress and the progress rate. Activities can be presented as geometrical shapes showing the occupation of the work site over time such that conflicting access can be detected visually. Different types of activities are differentiated by color, fill pattern, line type, or special symbols. A symbolic drawing along the distance axis is often used to improve the understanding of the time–distance diagram.