How did long hold times become acceptable?

Integral interval timetable (ITF) - transferable from Switzerland to Germany?

This is a guest article by Felix Thoma. Please also read his other guest articles that have appeared on this blog. If you are also interested in publishing a guest article here, please write to us.

1 Introduction - Why is there a German clock at all?

For me as a Berliner, a dense local transport network with frequent trips and good connections is a matter of course. But even in Brandenburg, which is not far away, regional trains and buses are running at a much lower pace. This is obviously in stark contrast to the first principle of spatial planning, according to which equivalent infrastructural conditions in Germany are to be strived for.

So that there can be a transport offer not only in the cities but also in the countryside that fundamentally enables mobility even without a car, special emphasis must be placed on short transfer times, especially with lower frequencies, in order to keep the total travel time low. In rural regions in particular, short transfer times are also an important aspect of the quality of travel: After all, the quality of stay in the train stations there is usually poor.

In order for long-distance traffic to be successfully shifted to rail as well, there must be an attractive offer in order to be able to compete with the airplane as a fast means of transport, with the emerging long-distance bus as an inexpensive means of transport, or the car as a more direct means of transport. Today, however, many long-distance train lines are not operated (anymore) at regular intervals, which means that many German cities are in principle dependent on the long-distance traffic of Deutsche Bahn. From the goals of spatial planning one can deduce that more German cities should again have access to long-distance passenger rail transport. However, additional lines only make sense if they are well connected to the existing structure. This means that the timetables of the long-distance trains should be coordinated with each other and with those of the regional trains so that transfer times are short. The offer of a fast and continuous travel chain almost from door to door is probably the greatest potential competitive advantage of the train over the long-distance bus and the plane as other public transport, which are less integrated into the local transport, and a decisive part of the choice of transport over the motorized individual transport .

For these reasons, the nationwide introduction of a so-called integral clock timetable (ITF) based on the Swiss model is called for, which was even agreed in the coalition agreement between the Union and the SPD under the heading Deutschland-Takt 2013 and was then examined in a feasibility study on behalf of the Federal Ministry of Transport . The aim of this article is to explain which concept is behind the term ITF, how it has already been implemented throughout Switzerland and regionally in Germany, and to what extent this would also be possible nationwide in this country.

2 Integral cycle timetable in theory

2.1 Timetable and symmetry

At a Timed timetable the trains on a line run at fixed time intervals. In rail transport, this is usually hourly, but the half-hourly or two-hour intervals are also widespread. The interval timetable not only offers customers an easy-to-remember and reliable offer, but also great advantages for the transport company: Since the operating sequence is repeated regularly, it can be transferred from one hour to other hours, thus simplifying the planning effort.

Single-cycle timetables, however, are rather rare because the different traffic volumes during the day or operational requirements in practice result in additional trips, cycle gaps or other deviations. Apart from that, the regular timetable is widespread in most Central European countries (especially in Germany, Austria, Switzerland and the Benelux countries). In France, too, there is now a tendency towards regular timetables, while in most Eastern European countries irregular timetables continue to prevail.

On a railway line in the cycle timetable, the trains meet in the opposite direction at regular intervals with a length of half the cycle time, i.e. every 30 minutes at hourly intervals. The times at which these train encounters occur are called Symmetry times. So there are two per hour at hourly intervals Symmetry minutes, whereby the one symmetry minute results from the other symmetry minute by adding or subtracting half the cycle time. The two different minutes of symmetry correspond to different train crossing points.

The timetables of the direction and opposite direction of a line are mirrored in the symmetry minutes. For a line every hour with the symmetry minute 0, the sum of the departure time of a train and the arrival time of its counter train at the same station is always 60.

2.2  Integral cycle timetable and nodes

The Integral cycle schedule, Integrated cycle schedule or short ITF is a timetable model in which the timetable is not planned individually for each line, but rather the clock timetables of different train and bus routes are viewed in an integrated manner and coordinated with one another. The aim is to offer a comprehensive transport network in which the connections are optimized as much as possible. In Central Europe, there is already talk of an integral cycle timetable in numerous regions, although this is differently developed from region to region. The timetables known as ITF, however, are almost without exception symmetrical clock timetables.

At a symmetrical cycle schedule