Post-WWII Timetabling – how the system worked; and an anomaly

To operate a two-way system with only one pipe, a complicated timetable had to be devised - and adhered to. There was a signalling system, using telegraph cables laid alongside the pipes, to notify despatch (after WWII phone lines were used). Look at the timetables on page 78 of Turner (large PDF file; a copy of p78 is at the end of this page). It’s described as "Ausschnitt vom Fahrplan der Rp. Stand v. Okt 1955" – ie, a piece of the Rohrpost timetable for Oct 1955.

[Compare the arrangements in Post- usw Dienst im Lokalpost-Rayon von Wien: Feb 1892]

First, an easy one: PA110 (Währing) to PA69 (Ayrenhoffgasse): Turner table, right-hand column, second section. Headings from the other tables.

Column (1) is headed "Entfernung in Metern" = length of pipe run; (2) is "Betriebskraft" = source of air power; (3) is "Schlußzug" = time of last train which in all these tables is "x)" ie see footnote - which is absent from the Ausschnitt as are the rightmost columns; (4) is "Betriebskraft" = source of air power for the journey in the other direction.

This means: The first train of the day from 110 to 69 left at 06:50, arriving at 06:52. Trains then left at 07:10, 07:30, 07:50, 08:10 etc until the last train at 18:50; all arriving 2 minutes later. In the other direction from 69 to 110, the first train was 07:04, then 07:24, 07:44, 08:04 etc.

The trains from PA110 to PA69 were blown down the pipe by compressed air from the machines at PA110. See the 1956 map below, where the large black circle at PA110 indicates a "Rp-Maschinenhaus".

From the table a time-movement diagram can be constructed, showing an orderly one-way-at-a-time flow in the pipe.

Now a complex example: TZST-PA1-PA40-PA43-PA79 (Zentrale-Fleischmarkt-Landstraße-St Marx-Simmering) - Turner table, top left section. Column headings as before; column 1 is missing on the original.

As in the first example, trains from the Zentrale leave every 20 minutes from 06:40 to 18:40 and proceed station by station (with brief pauses) to Simmering. The first train back began half-way along, at Landstraße. The 1956 map has centre-dotted black circles at PA40, PA43, & PA79 which indicate a "Rp-Kleinmaschinenanlage" ie a small installation capable of blowing or sucking a short train in either direction. Hence, complex 2-way traffic is feasible. Indeed since each leg of the route is a separate pipe with functionally separate equipment at each end, PA40 for example could blow to PA45 and suck from PA1 at the same time.

The first train leaves Zentrale at 06:40 and is blown by Zentrale’s compressors to PA1. This is Fleischmarkt, a Luftstation, which has an air and a vacuum reservoirs fed by two service pipes from Zentrale. At 06:42 the train is blown by PA1 from PA1 to PA40. At 06:47 it is sucked by PA43 from PA40 to PA43. And at 06:52 it is sucked by PA79 from PA43 to PA79.

Station
TZST
PA1
PA40
PA43
PA79

There is a Great Big Problem! Consider the 10:00 east-bound from Zentrale. The timing chart shows that at 10:07 the east-bound train (blue line on the diagram above) left PA40 for PA43, being sucked by PA43, and taking 4 minutes to get there. Meanwhile the 10:03 west-bound from PA79 (red line) left PA43 for PA40 at 10:08, being sucked by PA40, and taking 4 minutes to get there. Thus, at about 10:09 they were in the same place travelling in opposite directions; and during these 4 minutes vacuum was being applied at both ends of the pipe.

The resolution may be that the stated speed of the trains was "about 50 km per hour"; the pipe between PA40 and PA43 was 2021m, so it would take 2.4 minutes each way. Maybe the operators despatched the 10:07 train from PA40 to PA43, and as soon as it arrived changed over the valves and sent the 10:08 back.

A similar analysis of route 7 on the Turner timetable shows that the overlap is while both trains are stopped at PA110; and for route 9 both trains are stopped at PA129.