198408 – Metcalfe – Low Cost CTC Alternative

Ever since the earliest railways were opened it was realised that a bidirectional single line posed particular operating problems, with regard to trains travelling over the same line of metals in opposite directions.

In the days of the early colliery tramways this situation was controlled very loosely by regulations and the incidence of actually getting two trains travelling in opposite directions on the the same track, was very high, Due to low speeds however, inconvenience and embarrassment followed quite often by a fight between train crews, was the usual outcome.

As train speeds rose it was realised that this system of operation could not be allowed to continue consequently the railway pioneers looked for a method of achieving separation between trains.

The major advance in this direction was the introduction of the early telegraph instruments of the single needle type, which allowed communication between stations so permitting the passage of trains to be monitored prior to a second train being permitted to enter a section. Parallel to this system the use of train orders was also developed, which we are all familiar with.

As time progressed more severe methods of operation were developed in the form of token, tablet and electric train staff instruments, of which many are still in use today.

Finally in the intervening years between the two world wars C.T.C. systems were developed, basically as we know them today, giving all the advantages of secure block sections combined with the concept of overall control by one operator of a complete section of line as in the train order system.

C.T.C. systems have one major disadvantage to modern railway administration, and that is the relatively high cost and generally, the continued use of many hundreds of kilometres of pole line which is expensive to maintain.

In my talk today I would like to firstly consider how the cost of C.T.C. schemes for the more major routes could be reduced without losing integrity or flexibility of the system and then continue to low cost alternatives to obsolescent and labour intensive systems used on low density traffic lines.