in transportation work, a plan in the form of a graph or a table showing the organization of a transportation process. Such a chart is usually constructed in the coordinates “route-time.” Time is plotted along the X-axis (in days, hours, and minutes). Distance between points (stations, ports, airports) is plotted along the v-axis. In some special cases (as in air transport) the coordinates “time-route” are also used, as well as horizontal charts.
A traffic chart is of particular importance in railroad transportation where extreme accuracy and perfect coordination in the work of the subdivisions and services is required, as well as a stringent observance of safety requirements. In the Soviet Union a new traffic chart is introduced simultaneously (usually in May) for the entire system of railroads. Traffic charts and train schedules show, down to a minute, the time of arrival and departure of trains at each station. Traffic charts can be classified according to the use of the main track as follows: (a) one-track (two-sided) charts and (b) two-track (one-sided) charts. Traffic charts for individual railroad sections are constructed taking into account the traffic conditions in the local railroad stations. Traffic charts and train schedules are used by the railroads of most countries, with some details differing from country to country.
Charts showing operations of seagoing ships include a chart of ship traffic and a chart of the number of ships in ports. Such charts are constructed in the coordinates “route-time” (inclined chart) or the coordinates “ship-time” (horizontal chart). They also may be constructed in tabular form. Such traffic charts can be classified by the type of traffic schedule (line traffic or single cruise) and by navigational routes (coastal or foreign). Such charts are compiled for each month and use a 24-hour period as a time unit. However, the 24 hours are sometimes subdivided into periods. For regularly scheduled line ships and for combined freight-passenger vessels a traffic schedule is compiled either for a navigational period or the winter or summer season. In the operation of inland waterways, traffic charts coordinate the work of fleets, ports, and ship-repair yards; they also coordinate the activities of these facilities with other modes of transportation, as well as with customers’ requirements. These charts can be classified according to the way the work of a fleet is organized (scheduled line traffic, single cruise, or an expedition). The time period for which a traffic chart remains valid depends on navigational conditions and on seasonal variations in the cargo and passenger flow. Traffic charts for passenger fleets are constructed taking into consideration the purpose of a passenger line (transit, local, excursion, or suburban) and the variability of passenger flow (seasonal, daily, or hourly variation).
Charts and schedules for air traffic include passenger flights and cargo flights. They show the flight number, the type of aircraft, the frequency of flights, and also the departure and arrival times at an airport. Such schedules are revised twice a year, in summer and in winter, with due regard to navigational conditions.
Charts and schedules for automotive, or bus, traffic ensure a rhythmic utilization of the equipment (rolling stock). The traffic charts used here include those for shuttle routes (between points A and B) and ring routes (A, B, C, A). The traffic charts show loaded runs, empty runs, and also the “zero run” (from the garage to the starting point of the route) for each car. The traffic schedule shows the departure time from the point where the route originates and the arrival time at the end point of the route; the time of passage through control points is also shown.
E. S. SERGEEV