Class 74 electrodiesel locomotives of British Rail Southern Region, with particular reference to the control system

The paper traces the reasons for, and the development of, the booster-type locomotives used on the Southern Region of British Railways. The latest locomotives of this type, introduced in 1967 on the electrification of the Waterloo-Bournemouth line, are described with particular reference to the multiple unit or `push-pull¿ train-control system, and the application of solid-state equipment to the locomotive-control scheme. The subsequent service experience with these locomotives is related, and the lessons to be learnt from this development are discussed.