198608 – Nobbs – Intermittent Automatic Train Control & Associated Identification Systems

The Plessey Company has been involved with the design, manufacture and installation of vehicular identification systems for more than ten years. The basic system is known as “IDENT-ALL” and consists of transponders and interrogators which maybe vehicle mounted and fixed located in any convenient combination, i.e. the system may have the transponder fixed to the road or track and the interrogator mounted on the vehicle or vice versa.

Plessey has supplied British Rail (BR) with a system for use with the Advanced Passenger Trains (APT) operating between London (Euston) and Glasgow via the West Coast main line (Birmingham – Crewe – Preston – Carlisle). The purpose of this system was to enhance the APT’S operation in the discrimination of conventional speed restrictions and the higher figures for the APT. This was introduced to avoid the proliferation of further trackside speed indications which could be confusing to the drivers. The driver’s display is a electromechanical type developed by BR.

The APT is now out of service, however it has been used as a test bed for track Transponder type control systems and has been incorporated into the BR “DISC” System (Drivers’ Indication and Speed Control). BR issued Tenders in 1985 and Plessey bid as a subcontractor to GEC Westinghouse and ML. BR did not let a contract and the specification has been rewritten and is due for release in August, 1986.

The Glasgow underground system is one which utilises the Plessey “INDENT-ALL” system for the automatic control of speed, stopping and starting of trains and is based upon equipment supplied to BR for the This system is virtually fail safe even though it is normally automatic the driver has over-riding control of the train. Should a failure be detected in the automatic control mode the brakes are applied. For safety the automatic control system is protected by a separate mechanical stop system which applies to brakes if a signal at RED.

The Glasgow Plessey “IDENT-ALL” system has been successfully operating for some years now and although it is a unique non-network connected railway system it is an example of an automatic Train Control System.

The British Colombia Railway in Canada let a contract to Glenayre Electronics in the mid 1970’s to provide an alternative train operating system.

This system known as “LIC” (Location, Identification and Control) is intended to replace train order control where normal capacity is exceeded by the level of traffic. It also maybe used to enhance conventional CTC by providing detailed speed and location information. The BC Railways system has been installed on the 154 miles long Squamish Sub-division and thirty-six locomotives and thirty cabooses have been equipped for LIC operation.

As of December, 1984, Dynamic Sciences acquired the transportation business of Glenayre Electronics Limited. Coming over to DSL from Glenayre was Dr. Richard Pomeroy and his staff who currently maintain offices and research centre in Vancouver BC. Glenayre Electronics still manufacture various items of Railway equipment for DSL such as DIGITAIR end of train monitoring.

DSL is actively working with the Advanced Train Control System Committee (AAR and RAC) in preparing specification’s for the generic system to be used throughout North America.